From b1b44f777c740f8b4317c1a8e44286f228e21541 Mon Sep 17 00:00:00 2001 From: Mike Frysinger Date: Tue, 1 Mar 2022 00:30:46 -0500 Subject: newlib: rename mallocr.c to _mallocr.c This file is a little confusing: it provides all of the mallocr logic, but is compiled multiple times to produce a unique symbol each time. For example, building mallocr.c with -DDEFINE_FREER produces freer.o that only defines _free_r(). This is fine for most symbols, but it's a little confusing when defining mallocr itself -- we produce a file with the same symbol name, but we still need -DDEFINE_MALLOCR. In order to move the logic from the build rules to source files, using mallocr.c both as a multiplexer and for defining a single symbol is a bit tricky. It's possible (if we add a lot of redundant preprocessor checks to mallocr.c, or we add complicated build flags just for this one files), but it's easier if we simply rename this to a dedicated file. So let's do that. We do this as a dedicated commit because the next one will create a new mallocr.c file and git's automatic diff algorithms can handle trivial renames, but it can't handle renames+creates in the same commit. --- newlib/libc/stdlib/Makefile.am | 24 +- newlib/libc/stdlib/Makefile.in | 24 +- newlib/libc/stdlib/_mallocr.c | 3719 ++++++++++++++++++++++++++++++++++++++++ newlib/libc/stdlib/mallocr.c | 3719 ---------------------------------------- 4 files changed, 3743 insertions(+), 3743 deletions(-) create mode 100644 newlib/libc/stdlib/_mallocr.c delete mode 100644 newlib/libc/stdlib/mallocr.c (limited to 'newlib/libc') diff --git a/newlib/libc/stdlib/Makefile.am b/newlib/libc/stdlib/Makefile.am index 950ad98..cb2fbe8 100644 --- a/newlib/libc/stdlib/Makefile.am +++ b/newlib/libc/stdlib/Makefile.am @@ -180,40 +180,40 @@ lib_a_CFLAGS = $(AM_CFLAGS) lib_a_DEPENDENCIES = $(LIBADD_OBJS) $(ELIX_OBJS) LIB_COMPILE = $(AM_V_CC)$(COMPILE) -$(lpfx)mallocr.o: mallocr.c +$(lpfx)mallocr.o: _mallocr.c $(LIB_COMPILE) -DDEFINE_MALLOC -c $< -o $@ -$(lpfx)freer.o: mallocr.c +$(lpfx)freer.o: _mallocr.c $(LIB_COMPILE) -DDEFINE_FREE -c $< -o $@ -$(lpfx)reallocr.o: mallocr.c +$(lpfx)reallocr.o: _mallocr.c $(LIB_COMPILE) -DDEFINE_REALLOC -c $< -o $@ -$(lpfx)callocr.o: mallocr.c +$(lpfx)callocr.o: _mallocr.c $(LIB_COMPILE) -DDEFINE_CALLOC -c $< -o $@ -$(lpfx)cfreer.o: mallocr.c +$(lpfx)cfreer.o: _mallocr.c $(LIB_COMPILE) -DDEFINE_CFREE -c $< -o $@ -$(lpfx)malignr.o: mallocr.c +$(lpfx)malignr.o: _mallocr.c $(LIB_COMPILE) -DDEFINE_MEMALIGN -c $< -o $@ -$(lpfx)vallocr.o: mallocr.c +$(lpfx)vallocr.o: _mallocr.c $(LIB_COMPILE) -DDEFINE_VALLOC -c $< -o $@ -$(lpfx)pvallocr.o: mallocr.c +$(lpfx)pvallocr.o: _mallocr.c $(LIB_COMPILE) -DDEFINE_PVALLOC -c $< -o $@ -$(lpfx)mallinfor.o: mallocr.c +$(lpfx)mallinfor.o: _mallocr.c $(LIB_COMPILE) -DDEFINE_MALLINFO -c $< -o $@ -$(lpfx)mallstatsr.o: mallocr.c +$(lpfx)mallstatsr.o: _mallocr.c $(LIB_COMPILE) -DDEFINE_MALLOC_STATS -c $< -o $@ -$(lpfx)msizer.o: mallocr.c +$(lpfx)msizer.o: _mallocr.c $(LIB_COMPILE) -DDEFINE_MALLOC_USABLE_SIZE -c $< -o $@ -$(lpfx)malloptr.o: mallocr.c +$(lpfx)malloptr.o: _mallocr.c $(LIB_COMPILE) -DDEFINE_MALLOPT -c $< -o $@ $(lpfx)dtoa.o: dtoa.c mprec.h diff --git a/newlib/libc/stdlib/Makefile.in b/newlib/libc/stdlib/Makefile.in index b201e05..10426dd 100644 --- a/newlib/libc/stdlib/Makefile.in +++ b/newlib/libc/stdlib/Makefile.in @@ -1475,40 +1475,40 @@ uninstall-am: .PRECIOUS: Makefile -$(lpfx)mallocr.o: mallocr.c +$(lpfx)mallocr.o: _mallocr.c $(LIB_COMPILE) -DDEFINE_MALLOC -c $< -o $@ -$(lpfx)freer.o: mallocr.c +$(lpfx)freer.o: _mallocr.c $(LIB_COMPILE) -DDEFINE_FREE -c $< -o $@ -$(lpfx)reallocr.o: mallocr.c +$(lpfx)reallocr.o: _mallocr.c $(LIB_COMPILE) -DDEFINE_REALLOC -c $< -o $@ -$(lpfx)callocr.o: mallocr.c +$(lpfx)callocr.o: _mallocr.c $(LIB_COMPILE) -DDEFINE_CALLOC -c $< -o $@ -$(lpfx)cfreer.o: mallocr.c +$(lpfx)cfreer.o: _mallocr.c $(LIB_COMPILE) -DDEFINE_CFREE -c $< -o $@ -$(lpfx)malignr.o: mallocr.c +$(lpfx)malignr.o: _mallocr.c $(LIB_COMPILE) -DDEFINE_MEMALIGN -c $< -o $@ -$(lpfx)vallocr.o: mallocr.c +$(lpfx)vallocr.o: _mallocr.c $(LIB_COMPILE) -DDEFINE_VALLOC -c $< -o $@ -$(lpfx)pvallocr.o: mallocr.c +$(lpfx)pvallocr.o: _mallocr.c $(LIB_COMPILE) -DDEFINE_PVALLOC -c $< -o $@ -$(lpfx)mallinfor.o: mallocr.c +$(lpfx)mallinfor.o: _mallocr.c $(LIB_COMPILE) -DDEFINE_MALLINFO -c $< -o $@ -$(lpfx)mallstatsr.o: mallocr.c +$(lpfx)mallstatsr.o: _mallocr.c $(LIB_COMPILE) -DDEFINE_MALLOC_STATS -c $< -o $@ -$(lpfx)msizer.o: mallocr.c +$(lpfx)msizer.o: _mallocr.c $(LIB_COMPILE) -DDEFINE_MALLOC_USABLE_SIZE -c $< -o $@ -$(lpfx)malloptr.o: mallocr.c +$(lpfx)malloptr.o: _mallocr.c $(LIB_COMPILE) -DDEFINE_MALLOPT -c $< -o $@ $(lpfx)dtoa.o: dtoa.c mprec.h diff --git a/newlib/libc/stdlib/_mallocr.c b/newlib/libc/stdlib/_mallocr.c new file mode 100644 index 0000000..4b53997 --- /dev/null +++ b/newlib/libc/stdlib/_mallocr.c @@ -0,0 +1,3719 @@ +#include +#ifdef MALLOC_PROVIDED +int _dummy_mallocr = 1; +#elif defined(_NANO_MALLOC) +# include "nano-mallocr.c" +#else +/* ---------- To make a malloc.h, start cutting here ------------ */ + +/* + A version of malloc/free/realloc written by Doug Lea and released to the + public domain. Send questions/comments/complaints/performance data + to dl@cs.oswego.edu + +* VERSION 2.6.5 Wed Jun 17 15:55:16 1998 Doug Lea (dl at gee) + + Note: There may be an updated version of this malloc obtainable at + ftp://g.oswego.edu/pub/misc/malloc.c + Check before installing! + + Note: This version differs from 2.6.4 only by correcting a + statement ordering error that could cause failures only + when calls to this malloc are interposed with calls to + other memory allocators. + +* Why use this malloc? + + This is not the fastest, most space-conserving, most portable, or + most tunable malloc ever written. However it is among the fastest + while also being among the most space-conserving, portable and tunable. + Consistent balance across these factors results in a good general-purpose + allocator. For a high-level description, see + http://g.oswego.edu/dl/html/malloc.html + +* Synopsis of public routines + + (Much fuller descriptions are contained in the program documentation below.) + + malloc(size_t n); + Return a pointer to a newly allocated chunk of at least n bytes, or null + if no space is available. + free(Void_t* p); + Release the chunk of memory pointed to by p, or no effect if p is null. + realloc(Void_t* p, size_t n); + Return a pointer to a chunk of size n that contains the same data + as does chunk p up to the minimum of (n, p's size) bytes, or null + if no space is available. The returned pointer may or may not be + the same as p. If p is null, equivalent to malloc. Unless the + #define REALLOC_ZERO_BYTES_FREES below is set, realloc with a + size argument of zero (re)allocates a minimum-sized chunk. + memalign(size_t alignment, size_t n); + Return a pointer to a newly allocated chunk of n bytes, aligned + in accord with the alignment argument, which must be a power of + two. + valloc(size_t n); + Equivalent to memalign(pagesize, n), where pagesize is the page + size of the system (or as near to this as can be figured out from + all the includes/defines below.) + pvalloc(size_t n); + Equivalent to valloc(minimum-page-that-holds(n)), that is, + round up n to nearest pagesize. + calloc(size_t unit, size_t quantity); + Returns a pointer to quantity * unit bytes, with all locations + set to zero. + cfree(Void_t* p); + Equivalent to free(p). + malloc_trim(size_t pad); + Release all but pad bytes of freed top-most memory back + to the system. Return 1 if successful, else 0. + malloc_usable_size(Void_t* p); + Report the number usable allocated bytes associated with allocated + chunk p. This may or may not report more bytes than were requested, + due to alignment and minimum size constraints. + malloc_stats(); + Prints brief summary statistics on stderr. + mallinfo() + Returns (by copy) a struct containing various summary statistics. + mallopt(int parameter_number, int parameter_value) + Changes one of the tunable parameters described below. Returns + 1 if successful in changing the parameter, else 0. + +* Vital statistics: + + Alignment: 8-byte + 8 byte alignment is currently hardwired into the design. This + seems to suffice for all current machines and C compilers. + + Assumed pointer representation: 4 or 8 bytes + Code for 8-byte pointers is untested by me but has worked + reliably by Wolfram Gloger, who contributed most of the + changes supporting this. + + Assumed size_t representation: 4 or 8 bytes + Note that size_t is allowed to be 4 bytes even if pointers are 8. + + Minimum overhead per allocated chunk: 4 or 8 bytes + Each malloced chunk has a hidden overhead of 4 bytes holding size + and status information. + + Minimum allocated size: 4-byte ptrs: 16 bytes (including 4 overhead) + 8-byte ptrs: 24/32 bytes (including, 4/8 overhead) + + When a chunk is freed, 12 (for 4byte ptrs) or 20 (for 8 byte + ptrs but 4 byte size) or 24 (for 8/8) additional bytes are + needed; 4 (8) for a trailing size field + and 8 (16) bytes for free list pointers. Thus, the minimum + allocatable size is 16/24/32 bytes. + + Even a request for zero bytes (i.e., malloc(0)) returns a + pointer to something of the minimum allocatable size. + + Maximum allocated size: 4-byte size_t: 2^31 - 8 bytes + 8-byte size_t: 2^63 - 16 bytes + + It is assumed that (possibly signed) size_t bit values suffice to + represent chunk sizes. `Possibly signed' is due to the fact + that `size_t' may be defined on a system as either a signed or + an unsigned type. To be conservative, values that would appear + as negative numbers are avoided. + Requests for sizes with a negative sign bit will return a + minimum-sized chunk. + + Maximum overhead wastage per allocated chunk: normally 15 bytes + + Alignnment demands, plus the minimum allocatable size restriction + make the normal worst-case wastage 15 bytes (i.e., up to 15 + more bytes will be allocated than were requested in malloc), with + two exceptions: + 1. Because requests for zero bytes allocate non-zero space, + the worst case wastage for a request of zero bytes is 24 bytes. + 2. For requests >= mmap_threshold that are serviced via + mmap(), the worst case wastage is 8 bytes plus the remainder + from a system page (the minimal mmap unit); typically 4096 bytes. + +* Limitations + + Here are some features that are NOT currently supported + + * No user-definable hooks for callbacks and the like. + * No automated mechanism for fully checking that all accesses + to malloced memory stay within their bounds. + * No support for compaction. + +* Synopsis of compile-time options: + + People have reported using previous versions of this malloc on all + versions of Unix, sometimes by tweaking some of the defines + below. It has been tested most extensively on Solaris and + Linux. It is also reported to work on WIN32 platforms. + People have also reported adapting this malloc for use in + stand-alone embedded systems. + + The implementation is in straight, hand-tuned ANSI C. Among other + consequences, it uses a lot of macros. Because of this, to be at + all usable, this code should be compiled using an optimizing compiler + (for example gcc -O2) that can simplify expressions and control + paths. + + __STD_C (default: derived from C compiler defines) + Nonzero if using ANSI-standard C compiler, a C++ compiler, or + a C compiler sufficiently close to ANSI to get away with it. + DEBUG (default: NOT defined) + Define to enable debugging. Adds fairly extensive assertion-based + checking to help track down memory errors, but noticeably slows down + execution. + SEPARATE_OBJECTS (default: NOT defined) + Define this to compile into separate .o files. You must then + compile malloc.c several times, defining a DEFINE_* macro each + time. The list of DEFINE_* macros appears below. + MALLOC_LOCK (default: NOT defined) + MALLOC_UNLOCK (default: NOT defined) + Define these to C expressions which are run to lock and unlock + the malloc data structures. Calls may be nested; that is, + MALLOC_LOCK may be called more than once before the corresponding + MALLOC_UNLOCK calls. MALLOC_LOCK must avoid waiting for a lock + that it already holds. + MALLOC_ALIGNMENT (default: NOT defined) + Define this to 16 if you need 16 byte alignment instead of 8 byte alignment + which is the normal default. + REALLOC_ZERO_BYTES_FREES (default: NOT defined) + Define this if you think that realloc(p, 0) should be equivalent + to free(p). Otherwise, since malloc returns a unique pointer for + malloc(0), so does realloc(p, 0). + HAVE_MEMCPY (default: defined) + Define if you are not otherwise using ANSI STD C, but still + have memcpy and memset in your C library and want to use them. + Otherwise, simple internal versions are supplied. + USE_MEMCPY (default: 1 if HAVE_MEMCPY is defined, 0 otherwise) + Define as 1 if you want the C library versions of memset and + memcpy called in realloc and calloc (otherwise macro versions are used). + At least on some platforms, the simple macro versions usually + outperform libc versions. + HAVE_MMAP (default: defined as 1) + Define to non-zero to optionally make malloc() use mmap() to + allocate very large blocks. + HAVE_MREMAP (default: defined as 0 unless Linux libc set) + Define to non-zero to optionally make realloc() use mremap() to + reallocate very large blocks. + malloc_getpagesize (default: derived from system #includes) + Either a constant or routine call returning the system page size. + HAVE_USR_INCLUDE_MALLOC_H (default: NOT defined) + Optionally define if you are on a system with a /usr/include/malloc.h + that declares struct mallinfo. It is not at all necessary to + define this even if you do, but will ensure consistency. + INTERNAL_SIZE_T (default: size_t) + Define to a 32-bit type (probably `unsigned int') if you are on a + 64-bit machine, yet do not want or need to allow malloc requests of + greater than 2^31 to be handled. This saves space, especially for + very small chunks. + INTERNAL_LINUX_C_LIB (default: NOT defined) + Defined only when compiled as part of Linux libc. + Also note that there is some odd internal name-mangling via defines + (for example, internally, `malloc' is named `mALLOc') needed + when compiling in this case. These look funny but don't otherwise + affect anything. + _LIBC (default: NOT defined) + Defined only when compiled as part of the Cygnus newlib + distribution. + WIN32 (default: undefined) + Define this on MS win (95, nt) platforms to compile in sbrk emulation. + LACKS_UNISTD_H (default: undefined) + Define this if your system does not have a . + MORECORE (default: sbrk) + The name of the routine to call to obtain more memory from the system. + MORECORE_FAILURE (default: -1) + The value returned upon failure of MORECORE. + MORECORE_CLEARS (default 1) + True (1) if the routine mapped to MORECORE zeroes out memory (which + holds for sbrk). + DEFAULT_TRIM_THRESHOLD + DEFAULT_TOP_PAD + DEFAULT_MMAP_THRESHOLD + DEFAULT_MMAP_MAX + Default values of tunable parameters (described in detail below) + controlling interaction with host system routines (sbrk, mmap, etc). + These values may also be changed dynamically via mallopt(). The + preset defaults are those that give best performance for typical + programs/systems. + + +*/ + + + + +/* Preliminaries */ + +#ifndef __STD_C +#ifdef __STDC__ +#define __STD_C 1 +#else +#if __cplusplus +#define __STD_C 1 +#else +#define __STD_C 0 +#endif /*__cplusplus*/ +#endif /*__STDC__*/ +#endif /*__STD_C*/ + +#ifndef Void_t +#if __STD_C +#define Void_t void +#else +#define Void_t char +#endif +#endif /*Void_t*/ + +#if __STD_C +#include /* for size_t */ +#else +#include +#endif + +#ifdef __cplusplus +extern "C" { +#endif + +#include /* needed for malloc_stats */ +#include /* needed for overflow checks */ +#include /* needed to set errno to ENOMEM */ + +#ifdef WIN32 +#define WIN32_LEAN_AND_MEAN +#include +#endif + +/* + Compile-time options +*/ + + +/* + + Special defines for Cygnus newlib distribution. + + */ + +#ifdef _LIBC + +#include + +/* + In newlib, all the publically visible routines take a reentrancy + pointer. We don't currently do anything much with it, but we do + pass it to the lock routine. + */ + +#include + +#define POINTER_UINT unsigned _POINTER_INT +#define SEPARATE_OBJECTS +#define HAVE_MMAP 0 +#define MORECORE(size) _sbrk_r(reent_ptr, (size)) +#define MORECORE_CLEARS 0 +#define MALLOC_LOCK __malloc_lock(reent_ptr) +#define MALLOC_UNLOCK __malloc_unlock(reent_ptr) + +#ifdef __CYGWIN__ +# undef _WIN32 +# undef WIN32 +#endif + +#ifndef _WIN32 +#ifdef SMALL_MEMORY +#define malloc_getpagesize (128) +#else +#define malloc_getpagesize (4096) +#endif +#endif + +#if __STD_C +extern void __malloc_lock(struct _reent *); +extern void __malloc_unlock(struct _reent *); +#else +extern void __malloc_lock(); +extern void __malloc_unlock(); +#endif + +#if __STD_C +#define RARG struct _reent *reent_ptr, +#define RONEARG struct _reent *reent_ptr +#else +#define RARG reent_ptr +#define RONEARG reent_ptr +#define RDECL struct _reent *reent_ptr; +#endif + +#define RERRNO reent_ptr->_errno +#define RCALL reent_ptr, +#define RONECALL reent_ptr + +#else /* ! _LIBC */ + +#define POINTER_UINT unsigned long +#define RARG +#define RONEARG +#define RDECL +#define RERRNO errno +#define RCALL +#define RONECALL + +#endif /* ! _LIBC */ + +/* + Debugging: + + Because freed chunks may be overwritten with link fields, this + malloc will often die when freed memory is overwritten by user + programs. This can be very effective (albeit in an annoying way) + in helping track down dangling pointers. + + If you compile with -DDEBUG, a number of assertion checks are + enabled that will catch more memory errors. You probably won't be + able to make much sense of the actual assertion errors, but they + should help you locate incorrectly overwritten memory. The + checking is fairly extensive, and will slow down execution + noticeably. Calling malloc_stats or mallinfo with DEBUG set will + attempt to check every non-mmapped allocated and free chunk in the + course of computing the summmaries. (By nature, mmapped regions + cannot be checked very much automatically.) + + Setting DEBUG may also be helpful if you are trying to modify + this code. The assertions in the check routines spell out in more + detail the assumptions and invariants underlying the algorithms. + +*/ + +#if DEBUG +#include +#else +#define assert(x) ((void)0) +#endif + + +/* + SEPARATE_OBJECTS should be defined if you want each function to go + into a separate .o file. You must then compile malloc.c once per + function, defining the appropriate DEFINE_ macro. See below for the + list of macros. + */ + +#ifndef SEPARATE_OBJECTS +#define DEFINE_MALLOC +#define DEFINE_FREE +#define DEFINE_REALLOC +#define DEFINE_CALLOC +#define DEFINE_CFREE +#define DEFINE_MEMALIGN +#define DEFINE_VALLOC +#define DEFINE_PVALLOC +#define DEFINE_MALLINFO +#define DEFINE_MALLOC_STATS +#define DEFINE_MALLOC_USABLE_SIZE +#define DEFINE_MALLOPT + +#define STATIC static +#else +#define STATIC +#endif + +/* + Define MALLOC_LOCK and MALLOC_UNLOCK to C expressions to run to + lock and unlock the malloc data structures. MALLOC_LOCK may be + called recursively. + */ + +#ifndef MALLOC_LOCK +#define MALLOC_LOCK +#endif + +#ifndef MALLOC_UNLOCK +#define MALLOC_UNLOCK +#endif + +/* + INTERNAL_SIZE_T is the word-size used for internal bookkeeping + of chunk sizes. On a 64-bit machine, you can reduce malloc + overhead by defining INTERNAL_SIZE_T to be a 32 bit `unsigned int' + at the expense of not being able to handle requests greater than + 2^31. This limitation is hardly ever a concern; you are encouraged + to set this. However, the default version is the same as size_t. +*/ + +#ifndef INTERNAL_SIZE_T +#define INTERNAL_SIZE_T size_t +#endif + +/* + Following is needed on implementations whereby long > size_t. + The problem is caused because the code performs subtractions of + size_t values and stores the result in long values. In the case + where long > size_t and the first value is actually less than + the second value, the resultant value is positive. For example, + (long)(x - y) where x = 0 and y is 1 ends up being 0x00000000FFFFFFFF + which is 2*31 - 1 instead of 0xFFFFFFFFFFFFFFFF. This is due to the + fact that assignment from unsigned to signed won't sign extend. +*/ + +#define long_sub_size_t(x, y) \ + (sizeof (long) > sizeof (INTERNAL_SIZE_T) && x < y \ + ? -(long) (y - x) \ + : (long) (x - y)) + +/* + REALLOC_ZERO_BYTES_FREES should be set if a call to + realloc with zero bytes should be the same as a call to free. + Some people think it should. Otherwise, since this malloc + returns a unique pointer for malloc(0), so does realloc(p, 0). +*/ + + +/* #define REALLOC_ZERO_BYTES_FREES */ + + +/* + WIN32 causes an emulation of sbrk to be compiled in + mmap-based options are not currently supported in WIN32. +*/ + +/* #define WIN32 */ +#ifdef WIN32 +#define MORECORE wsbrk +#define HAVE_MMAP 0 +#endif + + +/* + HAVE_MEMCPY should be defined if you are not otherwise using + ANSI STD C, but still have memcpy and memset in your C library + and want to use them in calloc and realloc. Otherwise simple + macro versions are defined here. + + USE_MEMCPY should be defined as 1 if you actually want to + have memset and memcpy called. People report that the macro + versions are often enough faster than libc versions on many + systems that it is better to use them. + +*/ + +#define HAVE_MEMCPY + +/* Although the original macro is called USE_MEMCPY, newlib actually + uses memmove to handle cases whereby a platform's memcpy implementation + copies backwards and thus destructive overlap may occur in realloc + whereby we are reclaiming free memory prior to the old allocation. */ +#ifndef USE_MEMCPY +#ifdef HAVE_MEMCPY +#define USE_MEMCPY 1 +#else +#define USE_MEMCPY 0 +#endif +#endif + +#if (__STD_C || defined(HAVE_MEMCPY)) + +#if __STD_C +void* memset(void*, int, size_t); +void* memcpy(void*, const void*, size_t); +void* memmove(void*, const void*, size_t); +#else +Void_t* memset(); +Void_t* memcpy(); +Void_t* memmove(); +#endif +#endif + +#if USE_MEMCPY + +/* The following macros are only invoked with (2n+1)-multiples of + INTERNAL_SIZE_T units, with a positive integer n. This is exploited + for fast inline execution when n is small. */ + +#define MALLOC_ZERO(charp, nbytes) \ +do { \ + INTERNAL_SIZE_T mzsz = (nbytes); \ + if(mzsz <= 9*sizeof(mzsz)) { \ + INTERNAL_SIZE_T* mz = (INTERNAL_SIZE_T*) (charp); \ + if(mzsz >= 5*sizeof(mzsz)) { *mz++ = 0; \ + *mz++ = 0; \ + if(mzsz >= 7*sizeof(mzsz)) { *mz++ = 0; \ + *mz++ = 0; \ + if(mzsz >= 9*sizeof(mzsz)) { *mz++ = 0; \ + *mz++ = 0; }}} \ + *mz++ = 0; \ + *mz++ = 0; \ + *mz = 0; \ + } else memset((charp), 0, mzsz); \ +} while(0) + +#define MALLOC_COPY(dest,src,nbytes) \ +do { \ + INTERNAL_SIZE_T mcsz = (nbytes); \ + if(mcsz <= 9*sizeof(mcsz)) { \ + INTERNAL_SIZE_T* mcsrc = (INTERNAL_SIZE_T*) (src); \ + INTERNAL_SIZE_T* mcdst = (INTERNAL_SIZE_T*) (dest); \ + if(mcsz >= 5*sizeof(mcsz)) { *mcdst++ = *mcsrc++; \ + *mcdst++ = *mcsrc++; \ + if(mcsz >= 7*sizeof(mcsz)) { *mcdst++ = *mcsrc++; \ + *mcdst++ = *mcsrc++; \ + if(mcsz >= 9*sizeof(mcsz)) { *mcdst++ = *mcsrc++; \ + *mcdst++ = *mcsrc++; }}} \ + *mcdst++ = *mcsrc++; \ + *mcdst++ = *mcsrc++; \ + *mcdst = *mcsrc ; \ + } else memmove(dest, src, mcsz); \ +} while(0) + +#else /* !USE_MEMCPY */ + +/* Use Duff's device for good zeroing/copying performance. */ + +#define MALLOC_ZERO(charp, nbytes) \ +do { \ + INTERNAL_SIZE_T* mzp = (INTERNAL_SIZE_T*)(charp); \ + long mctmp = (nbytes)/sizeof(INTERNAL_SIZE_T), mcn; \ + if (mctmp < 8) mcn = 0; else { mcn = (mctmp-1)/8; mctmp %= 8; } \ + switch (mctmp) { \ + case 0: for(;;) { *mzp++ = 0; \ + case 7: *mzp++ = 0; \ + case 6: *mzp++ = 0; \ + case 5: *mzp++ = 0; \ + case 4: *mzp++ = 0; \ + case 3: *mzp++ = 0; \ + case 2: *mzp++ = 0; \ + case 1: *mzp++ = 0; if(mcn <= 0) break; mcn--; } \ + } \ +} while(0) + +#define MALLOC_COPY(dest,src,nbytes) \ +do { \ + INTERNAL_SIZE_T* mcsrc = (INTERNAL_SIZE_T*) src; \ + INTERNAL_SIZE_T* mcdst = (INTERNAL_SIZE_T*) dest; \ + long mctmp = (nbytes)/sizeof(INTERNAL_SIZE_T), mcn; \ + if (mctmp < 8) mcn = 0; else { mcn = (mctmp-1)/8; mctmp %= 8; } \ + switch (mctmp) { \ + case 0: for(;;) { *mcdst++ = *mcsrc++; \ + case 7: *mcdst++ = *mcsrc++; \ + case 6: *mcdst++ = *mcsrc++; \ + case 5: *mcdst++ = *mcsrc++; \ + case 4: *mcdst++ = *mcsrc++; \ + case 3: *mcdst++ = *mcsrc++; \ + case 2: *mcdst++ = *mcsrc++; \ + case 1: *mcdst++ = *mcsrc++; if(mcn <= 0) break; mcn--; } \ + } \ +} while(0) + +#endif + + +/* + Define HAVE_MMAP to optionally make malloc() use mmap() to + allocate very large blocks. These will be returned to the + operating system immediately after a free(). +*/ + +#ifndef HAVE_MMAP +#define HAVE_MMAP 1 +#endif + +/* + Define HAVE_MREMAP to make realloc() use mremap() to re-allocate + large blocks. This is currently only possible on Linux with + kernel versions newer than 1.3.77. +*/ + +#ifndef HAVE_MREMAP +#ifdef INTERNAL_LINUX_C_LIB +#define HAVE_MREMAP 1 +#else +#define HAVE_MREMAP 0 +#endif +#endif + +#if HAVE_MMAP + +#include +#include +#include + +#if !defined(MAP_ANONYMOUS) && defined(MAP_ANON) +#define MAP_ANONYMOUS MAP_ANON +#endif + +#endif /* HAVE_MMAP */ + +/* + Access to system page size. To the extent possible, this malloc + manages memory from the system in page-size units. + + The following mechanics for getpagesize were adapted from + bsd/gnu getpagesize.h +*/ + +#ifndef LACKS_UNISTD_H +# include +#endif + +#ifndef malloc_getpagesize +# ifdef _SC_PAGESIZE /* some SVR4 systems omit an underscore */ +# ifndef _SC_PAGE_SIZE +# define _SC_PAGE_SIZE _SC_PAGESIZE +# endif +# endif +# ifdef _SC_PAGE_SIZE +# define malloc_getpagesize sysconf(_SC_PAGE_SIZE) +# else +# if defined(BSD) || defined(DGUX) || defined(HAVE_GETPAGESIZE) + extern size_t getpagesize(); +# define malloc_getpagesize getpagesize() +# else +# include +# ifdef EXEC_PAGESIZE +# define malloc_getpagesize EXEC_PAGESIZE +# else +# ifdef NBPG +# ifndef CLSIZE +# define malloc_getpagesize NBPG +# else +# define malloc_getpagesize (NBPG * CLSIZE) +# endif +# else +# ifdef NBPC +# define malloc_getpagesize NBPC +# else +# ifdef PAGESIZE +# define malloc_getpagesize PAGESIZE +# else +# define malloc_getpagesize (4096) /* just guess */ +# endif +# endif +# endif +# endif +# endif +# endif +#endif + + + +/* + + This version of malloc supports the standard SVID/XPG mallinfo + routine that returns a struct containing the same kind of + information you can get from malloc_stats. It should work on + any SVID/XPG compliant system that has a /usr/include/malloc.h + defining struct mallinfo. (If you'd like to install such a thing + yourself, cut out the preliminary declarations as described above + and below and save them in a malloc.h file. But there's no + compelling reason to bother to do this.) + + The main declaration needed is the mallinfo struct that is returned + (by-copy) by mallinfo(). The SVID/XPG malloinfo struct contains a + bunch of fields, most of which are not even meaningful in this + version of malloc. Some of these fields are are instead filled by + mallinfo() with other numbers that might possibly be of interest. + + HAVE_USR_INCLUDE_MALLOC_H should be set if you have a + /usr/include/malloc.h file that includes a declaration of struct + mallinfo. If so, it is included; else an SVID2/XPG2 compliant + version is declared below. These must be precisely the same for + mallinfo() to work. + +*/ + +/* #define HAVE_USR_INCLUDE_MALLOC_H */ + +#if HAVE_USR_INCLUDE_MALLOC_H +#include "/usr/include/malloc.h" +#else + +/* SVID2/XPG mallinfo structure */ + +struct mallinfo { + int arena; /* total space allocated from system */ + int ordblks; /* number of non-inuse chunks */ + int smblks; /* unused -- always zero */ + int hblks; /* number of mmapped regions */ + int hblkhd; /* total space in mmapped regions */ + int usmblks; /* unused -- always zero */ + int fsmblks; /* unused -- always zero */ + int uordblks; /* total allocated space */ + int fordblks; /* total non-inuse space */ + int keepcost; /* top-most, releasable (via malloc_trim) space */ +}; + +/* SVID2/XPG mallopt options */ + +#define M_MXFAST 1 /* UNUSED in this malloc */ +#define M_NLBLKS 2 /* UNUSED in this malloc */ +#define M_GRAIN 3 /* UNUSED in this malloc */ +#define M_KEEP 4 /* UNUSED in this malloc */ + +#endif + +/* mallopt options that actually do something */ + +#define M_TRIM_THRESHOLD -1 +#define M_TOP_PAD -2 +#define M_MMAP_THRESHOLD -3 +#define M_MMAP_MAX -4 + + + +#ifndef DEFAULT_TRIM_THRESHOLD +#define DEFAULT_TRIM_THRESHOLD (128L * 1024L) +#endif + +/* + M_TRIM_THRESHOLD is the maximum amount of unused top-most memory + to keep before releasing via malloc_trim in free(). + + Automatic trimming is mainly useful in long-lived programs. + Because trimming via sbrk can be slow on some systems, and can + sometimes be wasteful (in cases where programs immediately + afterward allocate more large chunks) the value should be high + enough so that your overall system performance would improve by + releasing. + + The trim threshold and the mmap control parameters (see below) + can be traded off with one another. Trimming and mmapping are + two different ways of releasing unused memory back to the + system. Between these two, it is often possible to keep + system-level demands of a long-lived program down to a bare + minimum. For example, in one test suite of sessions measuring + the XF86 X server on Linux, using a trim threshold of 128K and a + mmap threshold of 192K led to near-minimal long term resource + consumption. + + If you are using this malloc in a long-lived program, it should + pay to experiment with these values. As a rough guide, you + might set to a value close to the average size of a process + (program) running on your system. Releasing this much memory + would allow such a process to run in memory. Generally, it's + worth it to tune for trimming rather tham memory mapping when a + program undergoes phases where several large chunks are + allocated and released in ways that can reuse each other's + storage, perhaps mixed with phases where there are no such + chunks at all. And in well-behaved long-lived programs, + controlling release of large blocks via trimming versus mapping + is usually faster. + + However, in most programs, these parameters serve mainly as + protection against the system-level effects of carrying around + massive amounts of unneeded memory. Since frequent calls to + sbrk, mmap, and munmap otherwise degrade performance, the default + parameters are set to relatively high values that serve only as + safeguards. + + The default trim value is high enough to cause trimming only in + fairly extreme (by current memory consumption standards) cases. + It must be greater than page size to have any useful effect. To + disable trimming completely, you can set to (unsigned long)(-1); + + +*/ + + +#ifndef DEFAULT_TOP_PAD +#define DEFAULT_TOP_PAD (0) +#endif + +/* + M_TOP_PAD is the amount of extra `padding' space to allocate or + retain whenever sbrk is called. It is used in two ways internally: + + * When sbrk is called to extend the top of the arena to satisfy + a new malloc request, this much padding is added to the sbrk + request. + + * When malloc_trim is called automatically from free(), + it is used as the `pad' argument. + + In both cases, the actual amount of padding is rounded + so that the end of the arena is always a system page boundary. + + The main reason for using padding is to avoid calling sbrk so + often. Having even a small pad greatly reduces the likelihood + that nearly every malloc request during program start-up (or + after trimming) will invoke sbrk, which needlessly wastes + time. + + Automatic rounding-up to page-size units is normally sufficient + to avoid measurable overhead, so the default is 0. However, in + systems where sbrk is relatively slow, it can pay to increase + this value, at the expense of carrying around more memory than + the program needs. + +*/ + + +#ifndef DEFAULT_MMAP_THRESHOLD +#define DEFAULT_MMAP_THRESHOLD (128 * 1024) +#endif + +/* + + M_MMAP_THRESHOLD is the request size threshold for using mmap() + to service a request. Requests of at least this size that cannot + be allocated using already-existing space will be serviced via mmap. + (If enough normal freed space already exists it is used instead.) + + Using mmap segregates relatively large chunks of memory so that + they can be individually obtained and released from the host + system. A request serviced through mmap is never reused by any + other request (at least not directly; the system may just so + happen to remap successive requests to the same locations). + + Segregating space in this way has the benefit that mmapped space + can ALWAYS be individually released back to the system, which + helps keep the system level memory demands of a long-lived + program low. Mapped memory can never become `locked' between + other chunks, as can happen with normally allocated chunks, which + menas that even trimming via malloc_trim would not release them. + + However, it has the disadvantages that: + + 1. The space cannot be reclaimed, consolidated, and then + used to service later requests, as happens with normal chunks. + 2. It can lead to more wastage because of mmap page alignment + requirements + 3. It causes malloc performance to be more dependent on host + system memory management support routines which may vary in + implementation quality and may impose arbitrary + limitations. Generally, servicing a request via normal + malloc steps is faster than going through a system's mmap. + + All together, these considerations should lead you to use mmap + only for relatively large requests. + + +*/ + + + +#ifndef DEFAULT_MMAP_MAX +#if HAVE_MMAP +#define DEFAULT_MMAP_MAX (64) +#else +#define DEFAULT_MMAP_MAX (0) +#endif +#endif + +/* + M_MMAP_MAX is the maximum number of requests to simultaneously + service using mmap. This parameter exists because: + + 1. Some systems have a limited number of internal tables for + use by mmap. + 2. In most systems, overreliance on mmap can degrade overall + performance. + 3. If a program allocates many large regions, it is probably + better off using normal sbrk-based allocation routines that + can reclaim and reallocate normal heap memory. Using a + small value allows transition into this mode after the + first few allocations. + + Setting to 0 disables all use of mmap. If HAVE_MMAP is not set, + the default value is 0, and attempts to set it to non-zero values + in mallopt will fail. +*/ + + + + +/* + + Special defines for linux libc + + Except when compiled using these special defines for Linux libc + using weak aliases, this malloc is NOT designed to work in + multithreaded applications. No semaphores or other concurrency + control are provided to ensure that multiple malloc or free calls + don't run at the same time, which could be disasterous. A single + semaphore could be used across malloc, realloc, and free (which is + essentially the effect of the linux weak alias approach). It would + be hard to obtain finer granularity. + +*/ + + +#ifdef INTERNAL_LINUX_C_LIB + +#if __STD_C + +Void_t * __default_morecore_init (ptrdiff_t); +Void_t *(*__morecore)(ptrdiff_t) = __default_morecore_init; + +#else + +Void_t * __default_morecore_init (); +Void_t *(*__morecore)() = __default_morecore_init; + +#endif + +#define MORECORE (*__morecore) +#define MORECORE_FAILURE 0 +#define MORECORE_CLEARS 1 + +#else /* INTERNAL_LINUX_C_LIB */ + +#ifndef _LIBC +#if __STD_C +extern Void_t* sbrk(ptrdiff_t); +#else +extern Void_t* sbrk(); +#endif +#endif + +#ifndef MORECORE +#define MORECORE sbrk +#endif + +#ifndef MORECORE_FAILURE +#define MORECORE_FAILURE -1 +#endif + +#ifndef MORECORE_CLEARS +#define MORECORE_CLEARS 1 +#endif + +#endif /* INTERNAL_LINUX_C_LIB */ + +#if defined(INTERNAL_LINUX_C_LIB) && defined(__ELF__) + +#define cALLOc __libc_calloc +#define fREe __libc_free +#define mALLOc __libc_malloc +#define mEMALIGn __libc_memalign +#define rEALLOc __libc_realloc +#define vALLOc __libc_valloc +#define pvALLOc __libc_pvalloc +#define mALLINFo __libc_mallinfo +#define mALLOPt __libc_mallopt + +#pragma weak calloc = __libc_calloc +#pragma weak free = __libc_free +#pragma weak cfree = __libc_free +#pragma weak malloc = __libc_malloc +#pragma weak memalign = __libc_memalign +#pragma weak realloc = __libc_realloc +#pragma weak valloc = __libc_valloc +#pragma weak pvalloc = __libc_pvalloc +#pragma weak mallinfo = __libc_mallinfo +#pragma weak mallopt = __libc_mallopt + +#else + +#ifdef _LIBC + +#define cALLOc _calloc_r +#define fREe _free_r +#define mALLOc _malloc_r +#define mEMALIGn _memalign_r +#define rEALLOc _realloc_r +#define vALLOc _valloc_r +#define pvALLOc _pvalloc_r +#define mALLINFo _mallinfo_r +#define mALLOPt _mallopt_r + +#define malloc_stats _malloc_stats_r +#define malloc_trim _malloc_trim_r +#define malloc_usable_size _malloc_usable_size_r + +#define malloc_update_mallinfo __malloc_update_mallinfo + +#define malloc_av_ __malloc_av_ +#define malloc_current_mallinfo __malloc_current_mallinfo +#define malloc_max_sbrked_mem __malloc_max_sbrked_mem +#define malloc_max_total_mem __malloc_max_total_mem +#define malloc_sbrk_base __malloc_sbrk_base +#define malloc_top_pad __malloc_top_pad +#define malloc_trim_threshold __malloc_trim_threshold + +#else /* ! _LIBC */ + +#define cALLOc calloc +#define fREe free +#define mALLOc malloc +#define mEMALIGn memalign +#define rEALLOc realloc +#define vALLOc valloc +#define pvALLOc pvalloc +#define mALLINFo mallinfo +#define mALLOPt mallopt + +#endif /* ! _LIBC */ +#endif + +/* Public routines */ + +#if __STD_C + +Void_t* mALLOc(RARG size_t); +void fREe(RARG Void_t*); +Void_t* rEALLOc(RARG Void_t*, size_t); +Void_t* mEMALIGn(RARG size_t, size_t); +Void_t* vALLOc(RARG size_t); +Void_t* pvALLOc(RARG size_t); +Void_t* cALLOc(RARG size_t, size_t); +void cfree(Void_t*); +int malloc_trim(RARG size_t); +size_t malloc_usable_size(RARG Void_t*); +void malloc_stats(RONEARG); +int mALLOPt(RARG int, int); +struct mallinfo mALLINFo(RONEARG); +#else +Void_t* mALLOc(); +void fREe(); +Void_t* rEALLOc(); +Void_t* mEMALIGn(); +Void_t* vALLOc(); +Void_t* pvALLOc(); +Void_t* cALLOc(); +void cfree(); +int malloc_trim(); +size_t malloc_usable_size(); +void malloc_stats(); +int mALLOPt(); +struct mallinfo mALLINFo(); +#endif + + +#ifdef __cplusplus +}; /* end of extern "C" */ +#endif + +/* ---------- To make a malloc.h, end cutting here ------------ */ + + +/* + Emulation of sbrk for WIN32 + All code within the ifdef WIN32 is untested by me. +*/ + + +#ifdef WIN32 + +#define AlignPage(add) (((add) + (malloc_getpagesize-1)) & \ +~(malloc_getpagesize-1)) + +/* resrve 64MB to insure large contiguous space */ +#define RESERVED_SIZE (1024*1024*64) +#define NEXT_SIZE (2048*1024) +#define TOP_MEMORY ((unsigned long)2*1024*1024*1024) + +struct GmListElement; +typedef struct GmListElement GmListElement; + +struct GmListElement +{ + GmListElement* next; + void* base; +}; + +static GmListElement* head = 0; +static unsigned int gNextAddress = 0; +static unsigned int gAddressBase = 0; +static unsigned int gAllocatedSize = 0; + +static +GmListElement* makeGmListElement (void* bas) +{ + GmListElement* this; + this = (GmListElement*)(void*)LocalAlloc (0, sizeof (GmListElement)); + ASSERT (this); + if (this) + { + this->base = bas; + this->next = head; + head = this; + } + return this; +} + +void gcleanup () +{ + BOOL rval; + ASSERT ( (head == NULL) || (head->base == (void*)gAddressBase)); + if (gAddressBase && (gNextAddress - gAddressBase)) + { + rval = VirtualFree ((void*)gAddressBase, + gNextAddress - gAddressBase, + MEM_DECOMMIT); + ASSERT (rval); + } + while (head) + { + GmListElement* next = head->next; + rval = VirtualFree (head->base, 0, MEM_RELEASE); + ASSERT (rval); + LocalFree (head); + head = next; + } +} + +static +void* findRegion (void* start_address, unsigned long size) +{ + MEMORY_BASIC_INFORMATION info; + while ((unsigned long)start_address < TOP_MEMORY) + { + VirtualQuery (start_address, &info, sizeof (info)); + if (info.State != MEM_FREE) + start_address = (char*)info.BaseAddress + info.RegionSize; + else if (info.RegionSize >= size) + return start_address; + else + start_address = (char*)info.BaseAddress + info.RegionSize; + } + return NULL; + +} + + +void* wsbrk (long size) +{ + void* tmp; + if (size > 0) + { + if (gAddressBase == 0) + { + gAllocatedSize = max (RESERVED_SIZE, AlignPage (size)); + gNextAddress = gAddressBase = + (unsigned int)VirtualAlloc (NULL, gAllocatedSize, + MEM_RESERVE, PAGE_NOACCESS); + } else if (AlignPage (gNextAddress + size) > (gAddressBase + +gAllocatedSize)) + { + long new_size = max (NEXT_SIZE, AlignPage (size)); + void* new_address = (void*)(gAddressBase+gAllocatedSize); + do + { + new_address = findRegion (new_address, new_size); + + if (new_address == 0) + return (void*)-1; + + gAddressBase = gNextAddress = + (unsigned int)VirtualAlloc (new_address, new_size, + MEM_RESERVE, PAGE_NOACCESS); + // repeat in case of race condition + // The region that we found has been snagged + // by another thread + } + while (gAddressBase == 0); + + ASSERT (new_address == (void*)gAddressBase); + + gAllocatedSize = new_size; + + if (!makeGmListElement ((void*)gAddressBase)) + return (void*)-1; + } + if ((size + gNextAddress) > AlignPage (gNextAddress)) + { + void* res; + res = VirtualAlloc ((void*)AlignPage (gNextAddress), + (size + gNextAddress - + AlignPage (gNextAddress)), + MEM_COMMIT, PAGE_READWRITE); + if (res == 0) + return (void*)-1; + } + tmp = (void*)gNextAddress; + gNextAddress = (unsigned int)tmp + size; + return tmp; + } + else if (size < 0) + { + unsigned int alignedGoal = AlignPage (gNextAddress + size); + /* Trim by releasing the virtual memory */ + if (alignedGoal >= gAddressBase) + { + VirtualFree ((void*)alignedGoal, gNextAddress - alignedGoal, + MEM_DECOMMIT); + gNextAddress = gNextAddress + size; + return (void*)gNextAddress; + } + else + { + VirtualFree ((void*)gAddressBase, gNextAddress - gAddressBase, + MEM_DECOMMIT); + gNextAddress = gAddressBase; + return (void*)-1; + } + } + else + { + return (void*)gNextAddress; + } +} + +#endif + + + +/* + Type declarations +*/ + + +struct malloc_chunk +{ + INTERNAL_SIZE_T prev_size; /* Size of previous chunk (if free). */ + INTERNAL_SIZE_T size; /* Size in bytes, including overhead. */ + struct malloc_chunk* fd; /* double links -- used only if free. */ + struct malloc_chunk* bk; +}; + +typedef struct malloc_chunk* mchunkptr; + +/* + + malloc_chunk details: + + (The following includes lightly edited explanations by Colin Plumb.) + + Chunks of memory are maintained using a `boundary tag' method as + described in e.g., Knuth or Standish. (See the paper by Paul + Wilson ftp://ftp.cs.utexas.edu/pub/garbage/allocsrv.ps for a + survey of such techniques.) Sizes of free chunks are stored both + in the front of each chunk and at the end. This makes + consolidating fragmented chunks into bigger chunks very fast. The + size fields also hold bits representing whether chunks are free or + in use. + + An allocated chunk looks like this: + + + chunk-> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + | Size of previous chunk, if allocated | | + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + | Size of chunk, in bytes |P| + mem-> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + | User data starts here... . + . . + . (malloc_usable_space() bytes) . + . | +nextchunk-> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + | Size of chunk | + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + + + Where "chunk" is the front of the chunk for the purpose of most of + the malloc code, but "mem" is the pointer that is returned to the + user. "Nextchunk" is the beginning of the next contiguous chunk. + + Chunks always begin on even word boundries, so the mem portion + (which is returned to the user) is also on an even word boundary, and + thus double-word aligned. + + Free chunks are stored in circular doubly-linked lists, and look like this: + + chunk-> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + | Size of previous chunk | + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + `head:' | Size of chunk, in bytes |P| + mem-> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + | Forward pointer to next chunk in list | + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + | Back pointer to previous chunk in list | + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + | Unused space (may be 0 bytes long) . + . . + . | +nextchunk-> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + `foot:' | Size of chunk, in bytes | + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + + The P (PREV_INUSE) bit, stored in the unused low-order bit of the + chunk size (which is always a multiple of two words), is an in-use + bit for the *previous* chunk. If that bit is *clear*, then the + word before the current chunk size contains the previous chunk + size, and can be used to find the front of the previous chunk. + (The very first chunk allocated always has this bit set, + preventing access to non-existent (or non-owned) memory.) + + Note that the `foot' of the current chunk is actually represented + as the prev_size of the NEXT chunk. (This makes it easier to + deal with alignments etc). + + The two exceptions to all this are + + 1. The special chunk `top', which doesn't bother using the + trailing size field since there is no + next contiguous chunk that would have to index off it. (After + initialization, `top' is forced to always exist. If it would + become less than MINSIZE bytes long, it is replenished via + malloc_extend_top.) + + 2. Chunks allocated via mmap, which have the second-lowest-order + bit (IS_MMAPPED) set in their size fields. Because they are + never merged or traversed from any other chunk, they have no + foot size or inuse information. + + Available chunks are kept in any of several places (all declared below): + + * `av': An array of chunks serving as bin headers for consolidated + chunks. Each bin is doubly linked. The bins are approximately + proportionally (log) spaced. There are a lot of these bins + (128). This may look excessive, but works very well in + practice. All procedures maintain the invariant that no + consolidated chunk physically borders another one. Chunks in + bins are kept in size order, with ties going to the + approximately least recently used chunk. + + The chunks in each bin are maintained in decreasing sorted order by + size. This is irrelevant for the small bins, which all contain + the same-sized chunks, but facilitates best-fit allocation for + larger chunks. (These lists are just sequential. Keeping them in + order almost never requires enough traversal to warrant using + fancier ordered data structures.) Chunks of the same size are + linked with the most recently freed at the front, and allocations + are taken from the back. This results in LRU or FIFO allocation + order, which tends to give each chunk an equal opportunity to be + consolidated with adjacent freed chunks, resulting in larger free + chunks and less fragmentation. + + * `top': The top-most available chunk (i.e., the one bordering the + end of available memory) is treated specially. It is never + included in any bin, is used only if no other chunk is + available, and is released back to the system if it is very + large (see M_TRIM_THRESHOLD). + + * `last_remainder': A bin holding only the remainder of the + most recently split (non-top) chunk. This bin is checked + before other non-fitting chunks, so as to provide better + locality for runs of sequentially allocated chunks. + + * Implicitly, through the host system's memory mapping tables. + If supported, requests greater than a threshold are usually + serviced via calls to mmap, and then later released via munmap. + +*/ + + + + + + +/* sizes, alignments */ + +#define SIZE_SZ (sizeof(INTERNAL_SIZE_T)) +#ifndef MALLOC_ALIGNMENT +#define MALLOC_ALIGN 8 +#define MALLOC_ALIGNMENT (SIZE_SZ < 4 ? 8 : (SIZE_SZ + SIZE_SZ)) +#else +#define MALLOC_ALIGN MALLOC_ALIGNMENT +#endif +#define MALLOC_ALIGN_MASK (MALLOC_ALIGNMENT - 1) +#define MINSIZE (sizeof(struct malloc_chunk)) + +/* conversion from malloc headers to user pointers, and back */ + +#define chunk2mem(p) ((Void_t*)((char*)(p) + 2*SIZE_SZ)) +#define mem2chunk(mem) ((mchunkptr)((char*)(mem) - 2*SIZE_SZ)) + +/* pad request bytes into a usable size */ + +#define request2size(req) \ + (((unsigned long)((req) + (SIZE_SZ + MALLOC_ALIGN_MASK)) < \ + (unsigned long)(MINSIZE + MALLOC_ALIGN_MASK)) ? ((MINSIZE + MALLOC_ALIGN_MASK) & ~(MALLOC_ALIGN_MASK)) : \ + (((req) + (SIZE_SZ + MALLOC_ALIGN_MASK)) & ~(MALLOC_ALIGN_MASK))) + +/* Check if m has acceptable alignment */ + +#define aligned_OK(m) (((unsigned long)((m)) & (MALLOC_ALIGN_MASK)) == 0) + + + + +/* + Physical chunk operations +*/ + + +/* size field is or'ed with PREV_INUSE when previous adjacent chunk in use */ + +#define PREV_INUSE 0x1 + +/* size field is or'ed with IS_MMAPPED if the chunk was obtained with mmap() */ + +#define IS_MMAPPED 0x2 + +/* Bits to mask off when extracting size */ + +#define SIZE_BITS (PREV_INUSE|IS_MMAPPED) + + +/* Ptr to next physical malloc_chunk. */ + +#define next_chunk(p) ((mchunkptr)( ((char*)(p)) + ((p)->size & ~PREV_INUSE) )) + +/* Ptr to previous physical malloc_chunk */ + +#define prev_chunk(p)\ + ((mchunkptr)( ((char*)(p)) - ((p)->prev_size) )) + + +/* Treat space at ptr + offset as a chunk */ + +#define chunk_at_offset(p, s) ((mchunkptr)(((char*)(p)) + (s))) + + + + +/* + Dealing with use bits +*/ + +/* extract p's inuse bit */ + +#define inuse(p)\ +((((mchunkptr)(((char*)(p))+((p)->size & ~PREV_INUSE)))->size) & PREV_INUSE) + +/* extract inuse bit of previous chunk */ + +#define prev_inuse(p) ((p)->size & PREV_INUSE) + +/* check for mmap()'ed chunk */ + +#define chunk_is_mmapped(p) ((p)->size & IS_MMAPPED) + +/* set/clear chunk as in use without otherwise disturbing */ + +#define set_inuse(p)\ +((mchunkptr)(((char*)(p)) + ((p)->size & ~PREV_INUSE)))->size |= PREV_INUSE + +#define clear_inuse(p)\ +((mchunkptr)(((char*)(p)) + ((p)->size & ~PREV_INUSE)))->size &= ~(PREV_INUSE) + +/* check/set/clear inuse bits in known places */ + +#define inuse_bit_at_offset(p, s)\ + (((mchunkptr)(((char*)(p)) + (s)))->size & PREV_INUSE) + +#define set_inuse_bit_at_offset(p, s)\ + (((mchunkptr)(((char*)(p)) + (s)))->size |= PREV_INUSE) + +#define clear_inuse_bit_at_offset(p, s)\ + (((mchunkptr)(((char*)(p)) + (s)))->size &= ~(PREV_INUSE)) + + + + +/* + Dealing with size fields +*/ + +/* Get size, ignoring use bits */ + +#define chunksize(p) ((p)->size & ~(SIZE_BITS)) + +/* Set size at head, without disturbing its use bit */ + +#define set_head_size(p, s) ((p)->size = (((p)->size & PREV_INUSE) | (s))) + +/* Set size/use ignoring previous bits in header */ + +#define set_head(p, s) ((p)->size = (s)) + +/* Set size at footer (only when chunk is not in use) */ + +#define set_foot(p, s) (((mchunkptr)((char*)(p) + (s)))->prev_size = (s)) + + + + + +/* + Bins + + The bins, `av_' are an array of pairs of pointers serving as the + heads of (initially empty) doubly-linked lists of chunks, laid out + in a way so that each pair can be treated as if it were in a + malloc_chunk. (This way, the fd/bk offsets for linking bin heads + and chunks are the same). + + Bins for sizes < 512 bytes contain chunks of all the same size, spaced + 8 bytes apart. Larger bins are approximately logarithmically + spaced. (See the table below.) The `av_' array is never mentioned + directly in the code, but instead via bin access macros. + + Bin layout: + + 64 bins of size 8 + 32 bins of size 64 + 16 bins of size 512 + 8 bins of size 4096 + 4 bins of size 32768 + 2 bins of size 262144 + 1 bin of size what's left + + There is actually a little bit of slop in the numbers in bin_index + for the sake of speed. This makes no difference elsewhere. + + The special chunks `top' and `last_remainder' get their own bins, + (this is implemented via yet more trickery with the av_ array), + although `top' is never properly linked to its bin since it is + always handled specially. + +*/ + +#ifdef SEPARATE_OBJECTS +#define av_ malloc_av_ +#endif + +#define NAV 128 /* number of bins */ + +typedef struct malloc_chunk* mbinptr; + +/* access macros */ + +#define bin_at(i) ((mbinptr)((char*)&(av_[2*(i) + 2]) - 2*SIZE_SZ)) +#define next_bin(b) ((mbinptr)((char*)(b) + 2 * sizeof(mbinptr))) +#define prev_bin(b) ((mbinptr)((char*)(b) - 2 * sizeof(mbinptr))) + +/* + The first 2 bins are never indexed. The corresponding av_ cells are instead + used for bookkeeping. This is not to save space, but to simplify + indexing, maintain locality, and avoid some initialization tests. +*/ + +#define top (bin_at(0)->fd) /* The topmost chunk */ +#define last_remainder (bin_at(1)) /* remainder from last split */ + + +/* + Because top initially points to its own bin with initial + zero size, thus forcing extension on the first malloc request, + we avoid having any special code in malloc to check whether + it even exists yet. But we still need to in malloc_extend_top. +*/ + +#define initial_top ((mchunkptr)(bin_at(0))) + +/* Helper macro to initialize bins */ + +#define IAV(i) bin_at(i), bin_at(i) + +#ifdef DEFINE_MALLOC +STATIC mbinptr av_[NAV * 2 + 2] = { + 0, 0, + IAV(0), IAV(1), IAV(2), IAV(3), IAV(4), IAV(5), IAV(6), IAV(7), + IAV(8), IAV(9), IAV(10), IAV(11), IAV(12), IAV(13), IAV(14), IAV(15), + IAV(16), IAV(17), IAV(18), IAV(19), IAV(20), IAV(21), IAV(22), IAV(23), + IAV(24), IAV(25), IAV(26), IAV(27), IAV(28), IAV(29), IAV(30), IAV(31), + IAV(32), IAV(33), IAV(34), IAV(35), IAV(36), IAV(37), IAV(38), IAV(39), + IAV(40), IAV(41), IAV(42), IAV(43), IAV(44), IAV(45), IAV(46), IAV(47), + IAV(48), IAV(49), IAV(50), IAV(51), IAV(52), IAV(53), IAV(54), IAV(55), + IAV(56), IAV(57), IAV(58), IAV(59), IAV(60), IAV(61), IAV(62), IAV(63), + IAV(64), IAV(65), IAV(66), IAV(67), IAV(68), IAV(69), IAV(70), IAV(71), + IAV(72), IAV(73), IAV(74), IAV(75), IAV(76), IAV(77), IAV(78), IAV(79), + IAV(80), IAV(81), IAV(82), IAV(83), IAV(84), IAV(85), IAV(86), IAV(87), + IAV(88), IAV(89), IAV(90), IAV(91), IAV(92), IAV(93), IAV(94), IAV(95), + IAV(96), IAV(97), IAV(98), IAV(99), IAV(100), IAV(101), IAV(102), IAV(103), + IAV(104), IAV(105), IAV(106), IAV(107), IAV(108), IAV(109), IAV(110), IAV(111), + IAV(112), IAV(113), IAV(114), IAV(115), IAV(116), IAV(117), IAV(118), IAV(119), + IAV(120), IAV(121), IAV(122), IAV(123), IAV(124), IAV(125), IAV(126), IAV(127) +}; +#else +extern mbinptr av_[NAV * 2 + 2]; +#endif + + + +/* field-extraction macros */ + +#define first(b) ((b)->fd) +#define last(b) ((b)->bk) + +/* + Indexing into bins +*/ + +#define bin_index(sz) \ +(((((unsigned long)(sz)) >> 9) == 0) ? (((unsigned long)(sz)) >> 3): \ + ((((unsigned long)(sz)) >> 9) <= 4) ? 56 + (((unsigned long)(sz)) >> 6): \ + ((((unsigned long)(sz)) >> 9) <= 20) ? 91 + (((unsigned long)(sz)) >> 9): \ + ((((unsigned long)(sz)) >> 9) <= 84) ? 110 + (((unsigned long)(sz)) >> 12): \ + ((((unsigned long)(sz)) >> 9) <= 340) ? 119 + (((unsigned long)(sz)) >> 15): \ + ((((unsigned long)(sz)) >> 9) <= 1364) ? 124 + (((unsigned long)(sz)) >> 18): \ + 126) +/* + bins for chunks < 512 are all spaced SMALLBIN_WIDTH bytes apart, and hold + identically sized chunks. This is exploited in malloc. +*/ + +#define MAX_SMALLBIN_SIZE 512 +#define SMALLBIN_WIDTH 8 +#define SMALLBIN_WIDTH_BITS 3 +#define MAX_SMALLBIN (MAX_SMALLBIN_SIZE / SMALLBIN_WIDTH) - 1 + +#define smallbin_index(sz) (((unsigned long)(sz)) >> SMALLBIN_WIDTH_BITS) + +/* + Requests are `small' if both the corresponding and the next bin are small +*/ + +#define is_small_request(nb) (nb < MAX_SMALLBIN_SIZE - SMALLBIN_WIDTH) + + + +/* + To help compensate for the large number of bins, a one-level index + structure is used for bin-by-bin searching. `binblocks' is a + one-word bitvector recording whether groups of BINBLOCKWIDTH bins + have any (possibly) non-empty bins, so they can be skipped over + all at once during during traversals. The bits are NOT always + cleared as soon as all bins in a block are empty, but instead only + when all are noticed to be empty during traversal in malloc. +*/ + +#define BINBLOCKWIDTH 4 /* bins per block */ + +#define binblocks (bin_at(0)->size) /* bitvector of nonempty blocks */ + +/* bin<->block macros */ + +#define idx2binblock(ix) ((unsigned long)1 << (ix / BINBLOCKWIDTH)) +#define mark_binblock(ii) (binblocks |= idx2binblock(ii)) +#define clear_binblock(ii) (binblocks &= ~(idx2binblock(ii))) + + + + + +/* Other static bookkeeping data */ + +#ifdef SEPARATE_OBJECTS +#define trim_threshold malloc_trim_threshold +#define top_pad malloc_top_pad +#define n_mmaps_max malloc_n_mmaps_max +#define mmap_threshold malloc_mmap_threshold +#define sbrk_base malloc_sbrk_base +#define max_sbrked_mem malloc_max_sbrked_mem +#define max_total_mem malloc_max_total_mem +#define current_mallinfo malloc_current_mallinfo +#define n_mmaps malloc_n_mmaps +#define max_n_mmaps malloc_max_n_mmaps +#define mmapped_mem malloc_mmapped_mem +#define max_mmapped_mem malloc_max_mmapped_mem +#endif + +/* variables holding tunable values */ + +#ifdef DEFINE_MALLOC + +STATIC unsigned long trim_threshold = DEFAULT_TRIM_THRESHOLD; +STATIC unsigned long top_pad = DEFAULT_TOP_PAD; +#if HAVE_MMAP +STATIC unsigned int n_mmaps_max = DEFAULT_MMAP_MAX; +STATIC unsigned long mmap_threshold = DEFAULT_MMAP_THRESHOLD; +#endif + +/* The first value returned from sbrk */ +STATIC char* sbrk_base = (char*)(-1); + +/* The maximum memory obtained from system via sbrk */ +STATIC unsigned long max_sbrked_mem = 0; + +/* The maximum via either sbrk or mmap */ +STATIC unsigned long max_total_mem = 0; + +/* internal working copy of mallinfo */ +STATIC struct mallinfo current_mallinfo = { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 }; + +#if HAVE_MMAP + +/* Tracking mmaps */ + +STATIC unsigned int n_mmaps = 0; +STATIC unsigned int max_n_mmaps = 0; +STATIC unsigned long mmapped_mem = 0; +STATIC unsigned long max_mmapped_mem = 0; + +#endif + +#else /* ! DEFINE_MALLOC */ + +extern unsigned long trim_threshold; +extern unsigned long top_pad; +#if HAVE_MMAP +extern unsigned int n_mmaps_max; +extern unsigned long mmap_threshold; +#endif +extern char* sbrk_base; +extern unsigned long max_sbrked_mem; +extern unsigned long max_total_mem; +extern struct mallinfo current_mallinfo; +#if HAVE_MMAP +extern unsigned int n_mmaps; +extern unsigned int max_n_mmaps; +extern unsigned long mmapped_mem; +extern unsigned long max_mmapped_mem; +#endif + +#endif /* ! DEFINE_MALLOC */ + +/* The total memory obtained from system via sbrk */ +#define sbrked_mem (current_mallinfo.arena) + + + +/* + Debugging support +*/ + +#if DEBUG + + +/* + These routines make a number of assertions about the states + of data structures that should be true at all times. If any + are not true, it's very likely that a user program has somehow + trashed memory. (It's also possible that there is a coding error + in malloc. In which case, please report it!) +*/ + +#if __STD_C +static void do_check_chunk(mchunkptr p) +#else +static void do_check_chunk(p) mchunkptr p; +#endif +{ + INTERNAL_SIZE_T sz = p->size & ~PREV_INUSE; + + /* No checkable chunk is mmapped */ + assert(!chunk_is_mmapped(p)); + + /* Check for legal address ... */ + assert((char*)p >= sbrk_base); + if (p != top) + assert((char*)p + sz <= (char*)top); + else + assert((char*)p + sz <= sbrk_base + sbrked_mem); + +} + + +#if __STD_C +static void do_check_free_chunk(mchunkptr p) +#else +static void do_check_free_chunk(p) mchunkptr p; +#endif +{ + INTERNAL_SIZE_T sz = p->size & ~PREV_INUSE; + mchunkptr next = chunk_at_offset(p, sz); + + do_check_chunk(p); + + /* Check whether it claims to be free ... */ + assert(!inuse(p)); + + /* Unless a special marker, must have OK fields */ + if ((long)sz >= (long)MINSIZE) + { + assert((sz & MALLOC_ALIGN_MASK) == 0); + assert(aligned_OK(chunk2mem(p))); + /* ... matching footer field */ + assert(next->prev_size == sz); + /* ... and is fully consolidated */ + assert(prev_inuse(p)); + assert (next == top || inuse(next)); + + /* ... and has minimally sane links */ + assert(p->fd->bk == p); + assert(p->bk->fd == p); + } + else /* markers are always of size SIZE_SZ */ + assert(sz == SIZE_SZ); +} + +#if __STD_C +static void do_check_inuse_chunk(mchunkptr p) +#else +static void do_check_inuse_chunk(p) mchunkptr p; +#endif +{ + mchunkptr next = next_chunk(p); + do_check_chunk(p); + + /* Check whether it claims to be in use ... */ + assert(inuse(p)); + + /* ... and is surrounded by OK chunks. + Since more things can be checked with free chunks than inuse ones, + if an inuse chunk borders them and debug is on, it's worth doing them. + */ + if (!prev_inuse(p)) + { + mchunkptr prv = prev_chunk(p); + assert(next_chunk(prv) == p); + do_check_free_chunk(prv); + } + if (next == top) + { + assert(prev_inuse(next)); + assert(chunksize(next) >= MINSIZE); + } + else if (!inuse(next)) + do_check_free_chunk(next); + +} + +#if __STD_C +static void do_check_malloced_chunk(mchunkptr p, INTERNAL_SIZE_T s) +#else +static void do_check_malloced_chunk(p, s) mchunkptr p; INTERNAL_SIZE_T s; +#endif +{ + INTERNAL_SIZE_T sz = p->size & ~PREV_INUSE; + long room = long_sub_size_t(sz, s); + + do_check_inuse_chunk(p); + + /* Legal size ... */ + assert((long)sz >= (long)MINSIZE); + assert((sz & MALLOC_ALIGN_MASK) == 0); + assert(room >= 0); + assert(room < (long)MINSIZE); + + /* ... and alignment */ + assert(aligned_OK(chunk2mem(p))); + + + /* ... and was allocated at front of an available chunk */ + assert(prev_inuse(p)); + +} + + +#define check_free_chunk(P) do_check_free_chunk(P) +#define check_inuse_chunk(P) do_check_inuse_chunk(P) +#define check_chunk(P) do_check_chunk(P) +#define check_malloced_chunk(P,N) do_check_malloced_chunk(P,N) +#else +#define check_free_chunk(P) +#define check_inuse_chunk(P) +#define check_chunk(P) +#define check_malloced_chunk(P,N) +#endif + + + +/* + Macro-based internal utilities +*/ + + +/* + Linking chunks in bin lists. + Call these only with variables, not arbitrary expressions, as arguments. +*/ + +/* + Place chunk p of size s in its bin, in size order, + putting it ahead of others of same size. +*/ + + +#define frontlink(P, S, IDX, BK, FD) \ +{ \ + if (S < MAX_SMALLBIN_SIZE) \ + { \ + IDX = smallbin_index(S); \ + mark_binblock(IDX); \ + BK = bin_at(IDX); \ + FD = BK->fd; \ + P->bk = BK; \ + P->fd = FD; \ + FD->bk = BK->fd = P; \ + } \ + else \ + { \ + IDX = bin_index(S); \ + BK = bin_at(IDX); \ + FD = BK->fd; \ + if (FD == BK) mark_binblock(IDX); \ + else \ + { \ + while (FD != BK && S < chunksize(FD)) FD = FD->fd; \ + BK = FD->bk; \ + } \ + P->bk = BK; \ + P->fd = FD; \ + FD->bk = BK->fd = P; \ + } \ +} + + +/* take a chunk off a list */ + +#define unlink(P, BK, FD) \ +{ \ + BK = P->bk; \ + FD = P->fd; \ + FD->bk = BK; \ + BK->fd = FD; \ +} \ + +/* Place p as the last remainder */ + +#define link_last_remainder(P) \ +{ \ + last_remainder->fd = last_remainder->bk = P; \ + P->fd = P->bk = last_remainder; \ +} + +/* Clear the last_remainder bin */ + +#define clear_last_remainder \ + (last_remainder->fd = last_remainder->bk = last_remainder) + + + + + + +/* Routines dealing with mmap(). */ + +#if HAVE_MMAP + +#ifdef DEFINE_MALLOC + +#if __STD_C +static mchunkptr mmap_chunk(size_t size) +#else +static mchunkptr mmap_chunk(size) size_t size; +#endif +{ + size_t page_mask = malloc_getpagesize - 1; + mchunkptr p; + +#ifndef MAP_ANONYMOUS + static int fd = -1; +#endif + + if(n_mmaps >= n_mmaps_max) return 0; /* too many regions */ + + /* For mmapped chunks, the overhead is one SIZE_SZ unit larger, because + * there is no following chunk whose prev_size field could be used. + */ + size = (size + SIZE_SZ + page_mask) & ~page_mask; + +#ifdef MAP_ANONYMOUS + p = (mchunkptr)mmap(0, size, PROT_READ|PROT_WRITE, + MAP_PRIVATE|MAP_ANONYMOUS, -1, 0); +#else /* !MAP_ANONYMOUS */ + if (fd < 0) + { + fd = open("/dev/zero", O_RDWR); + if(fd < 0) return 0; + } + p = (mchunkptr)mmap(0, size, PROT_READ|PROT_WRITE, MAP_PRIVATE, fd, 0); +#endif + + if(p == (mchunkptr)-1) return 0; + + n_mmaps++; + if (n_mmaps > max_n_mmaps) max_n_mmaps = n_mmaps; + + /* We demand that eight bytes into a page must be 8-byte aligned. */ + assert(aligned_OK(chunk2mem(p))); + + /* The offset to the start of the mmapped region is stored + * in the prev_size field of the chunk; normally it is zero, + * but that can be changed in memalign(). + */ + p->prev_size = 0; + set_head(p, size|IS_MMAPPED); + + mmapped_mem += size; + if ((unsigned long)mmapped_mem > (unsigned long)max_mmapped_mem) + max_mmapped_mem = mmapped_mem; + if ((unsigned long)(mmapped_mem + sbrked_mem) > (unsigned long)max_total_mem) + max_total_mem = mmapped_mem + sbrked_mem; + return p; +} + +#endif /* DEFINE_MALLOC */ + +#ifdef SEPARATE_OBJECTS +#define munmap_chunk malloc_munmap_chunk +#endif + +#ifdef DEFINE_FREE + +#if __STD_C +STATIC void munmap_chunk(mchunkptr p) +#else +STATIC void munmap_chunk(p) mchunkptr p; +#endif +{ + INTERNAL_SIZE_T size = chunksize(p); + int ret; + + assert (chunk_is_mmapped(p)); + assert(! ((char*)p >= sbrk_base && (char*)p < sbrk_base + sbrked_mem)); + assert((n_mmaps > 0)); + assert(((p->prev_size + size) & (malloc_getpagesize-1)) == 0); + + n_mmaps--; + mmapped_mem -= (size + p->prev_size); + + ret = munmap((char *)p - p->prev_size, size + p->prev_size); + + /* munmap returns non-zero on failure */ + assert(ret == 0); +} + +#else /* ! DEFINE_FREE */ + +#if __STD_C +extern void munmap_chunk(mchunkptr); +#else +extern void munmap_chunk(); +#endif + +#endif /* ! DEFINE_FREE */ + +#if HAVE_MREMAP + +#ifdef DEFINE_REALLOC + +#if __STD_C +static mchunkptr mremap_chunk(mchunkptr p, size_t new_size) +#else +static mchunkptr mremap_chunk(p, new_size) mchunkptr p; size_t new_size; +#endif +{ + size_t page_mask = malloc_getpagesize - 1; + INTERNAL_SIZE_T offset = p->prev_size; + INTERNAL_SIZE_T size = chunksize(p); + char *cp; + + assert (chunk_is_mmapped(p)); + assert(! ((char*)p >= sbrk_base && (char*)p < sbrk_base + sbrked_mem)); + assert((n_mmaps > 0)); + assert(((size + offset) & (malloc_getpagesize-1)) == 0); + + /* Note the extra SIZE_SZ overhead as in mmap_chunk(). */ + new_size = (new_size + offset + SIZE_SZ + page_mask) & ~page_mask; + + cp = (char *)mremap((char *)p - offset, size + offset, new_size, 1); + + if (cp == (char *)-1) return 0; + + p = (mchunkptr)(cp + offset); + + assert(aligned_OK(chunk2mem(p))); + + assert((p->prev_size == offset)); + set_head(p, (new_size - offset)|IS_MMAPPED); + + mmapped_mem -= size + offset; + mmapped_mem += new_size; + if ((unsigned long)mmapped_mem > (unsigned long)max_mmapped_mem) + max_mmapped_mem = mmapped_mem; + if ((unsigned long)(mmapped_mem + sbrked_mem) > (unsigned long)max_total_mem) + max_total_mem = mmapped_mem + sbrked_mem; + return p; +} + +#endif /* DEFINE_REALLOC */ + +#endif /* HAVE_MREMAP */ + +#endif /* HAVE_MMAP */ + + + + +#ifdef DEFINE_MALLOC + +/* + Extend the top-most chunk by obtaining memory from system. + Main interface to sbrk (but see also malloc_trim). +*/ + +#if __STD_C +static void malloc_extend_top(RARG INTERNAL_SIZE_T nb) +#else +static void malloc_extend_top(RARG nb) RDECL INTERNAL_SIZE_T nb; +#endif +{ + char* brk; /* return value from sbrk */ + INTERNAL_SIZE_T front_misalign; /* unusable bytes at front of sbrked space */ + INTERNAL_SIZE_T correction; /* bytes for 2nd sbrk call */ + int correction_failed = 0; /* whether we should relax the assertion */ + char* new_brk; /* return of 2nd sbrk call */ + INTERNAL_SIZE_T top_size; /* new size of top chunk */ + + mchunkptr old_top = top; /* Record state of old top */ + INTERNAL_SIZE_T old_top_size = chunksize(old_top); + char* old_end = (char*)(chunk_at_offset(old_top, old_top_size)); + + /* Pad request with top_pad plus minimal overhead */ + + INTERNAL_SIZE_T sbrk_size = nb + top_pad + MINSIZE; + unsigned long pagesz = malloc_getpagesize; + + /* If not the first time through, round to preserve page boundary */ + /* Otherwise, we need to correct to a page size below anyway. */ + /* (We also correct below if an intervening foreign sbrk call.) */ + + if (sbrk_base != (char*)(-1)) + sbrk_size = (sbrk_size + (pagesz - 1)) & ~(pagesz - 1); + + brk = (char*)(MORECORE (sbrk_size)); + + /* Fail if sbrk failed or if a foreign sbrk call killed our space */ + if (brk == (char*)(MORECORE_FAILURE) || + (brk < old_end && old_top != initial_top)) + return; + + sbrked_mem += sbrk_size; + + if (brk == old_end /* can just add bytes to current top, unless + previous correction failed */ + && ((POINTER_UINT)old_end & (pagesz - 1)) == 0) + { + top_size = sbrk_size + old_top_size; + set_head(top, top_size | PREV_INUSE); + } + else + { + if (sbrk_base == (char*)(-1)) /* First time through. Record base */ + sbrk_base = brk; + else /* Someone else called sbrk(). Count those bytes as sbrked_mem. */ + sbrked_mem += brk - (char*)old_end; + + /* Guarantee alignment of first new chunk made from this space */ + front_misalign = (POINTER_UINT)chunk2mem(brk) & MALLOC_ALIGN_MASK; + if (front_misalign > 0) + { + correction = (MALLOC_ALIGNMENT) - front_misalign; + brk += correction; + } + else + correction = 0; + + /* Guarantee the next brk will be at a page boundary */ + correction += pagesz - ((POINTER_UINT)(brk + sbrk_size) & (pagesz - 1)); + + /* To guarantee page boundary, correction should be less than pagesz */ + correction &= (pagesz - 1); + + /* Allocate correction */ + new_brk = (char*)(MORECORE (correction)); + if (new_brk == (char*)(MORECORE_FAILURE)) + { + correction = 0; + correction_failed = 1; + new_brk = brk + sbrk_size; + if (front_misalign > 0) + new_brk -= (MALLOC_ALIGNMENT) - front_misalign; + } + + sbrked_mem += correction; + + top = (mchunkptr)brk; + top_size = new_brk - brk + correction; + set_head(top, top_size | PREV_INUSE); + + if (old_top != initial_top) + { + + /* There must have been an intervening foreign sbrk call. */ + /* A double fencepost is necessary to prevent consolidation */ + + /* If not enough space to do this, then user did something very wrong */ + if (old_top_size < MINSIZE) + { + set_head(top, PREV_INUSE); /* will force null return from malloc */ + return; + } + + /* Also keep size a multiple of MALLOC_ALIGNMENT */ + old_top_size = (old_top_size - 3*SIZE_SZ) & ~MALLOC_ALIGN_MASK; + set_head_size(old_top, old_top_size); + chunk_at_offset(old_top, old_top_size )->size = + SIZE_SZ|PREV_INUSE; + chunk_at_offset(old_top, old_top_size + SIZE_SZ)->size = + SIZE_SZ|PREV_INUSE; + /* If possible, release the rest. */ + if (old_top_size >= MINSIZE) + fREe(RCALL chunk2mem(old_top)); + } + } + + if ((unsigned long)sbrked_mem > (unsigned long)max_sbrked_mem) + max_sbrked_mem = sbrked_mem; +#if HAVE_MMAP + if ((unsigned long)(mmapped_mem + sbrked_mem) > (unsigned long)max_total_mem) + max_total_mem = mmapped_mem + sbrked_mem; +#else + if ((unsigned long)(sbrked_mem) > (unsigned long)max_total_mem) + max_total_mem = sbrked_mem; +#endif + + /* We always land on a page boundary */ + assert(((unsigned long)((char*)top + top_size) & (pagesz - 1)) == 0 + || correction_failed); +} + +#endif /* DEFINE_MALLOC */ + + +/* Main public routines */ + +#ifdef DEFINE_MALLOC + +/* + Malloc Algorthim: + + The requested size is first converted into a usable form, `nb'. + This currently means to add 4 bytes overhead plus possibly more to + obtain 8-byte alignment and/or to obtain a size of at least + MINSIZE (currently 16 bytes), the smallest allocatable size. + (All fits are considered `exact' if they are within MINSIZE bytes.) + + From there, the first successful of the following steps is taken: + + 1. The bin corresponding to the request size is scanned, and if + a chunk of exactly the right size is found, it is taken. + + 2. The most recently remaindered chunk is used if it is big + enough. This is a form of (roving) first fit, used only in + the absence of exact fits. Runs of consecutive requests use + the remainder of the chunk used for the previous such request + whenever possible. This limited use of a first-fit style + allocation strategy tends to give contiguous chunks + coextensive lifetimes, which improves locality and can reduce + fragmentation in the long run. + + 3. Other bins are scanned in increasing size order, using a + chunk big enough to fulfill the request, and splitting off + any remainder. This search is strictly by best-fit; i.e., + the smallest (with ties going to approximately the least + recently used) chunk that fits is selected. + + 4. If large enough, the chunk bordering the end of memory + (`top') is split off. (This use of `top' is in accord with + the best-fit search rule. In effect, `top' is treated as + larger (and thus less well fitting) than any other available + chunk since it can be extended to be as large as necessary + (up to system limitations). + + 5. If the request size meets the mmap threshold and the + system supports mmap, and there are few enough currently + allocated mmapped regions, and a call to mmap succeeds, + the request is allocated via direct memory mapping. + + 6. Otherwise, the top of memory is extended by + obtaining more space from the system (normally using sbrk, + but definable to anything else via the MORECORE macro). + Memory is gathered from the system (in system page-sized + units) in a way that allows chunks obtained across different + sbrk calls to be consolidated, but does not require + contiguous memory. Thus, it should be safe to intersperse + mallocs with other sbrk calls. + + + All allocations are made from the the `lowest' part of any found + chunk. (The implementation invariant is that prev_inuse is + always true of any allocated chunk; i.e., that each allocated + chunk borders either a previously allocated and still in-use chunk, + or the base of its memory arena.) + +*/ + +#if __STD_C +Void_t* mALLOc(RARG size_t bytes) +#else +Void_t* mALLOc(RARG bytes) RDECL size_t bytes; +#endif +{ +#ifdef MALLOC_PROVIDED + + return malloc (bytes); // Make sure that the pointer returned by malloc is returned back. + +#else + + mchunkptr victim; /* inspected/selected chunk */ + INTERNAL_SIZE_T victim_size; /* its size */ + int idx; /* index for bin traversal */ + mbinptr bin; /* associated bin */ + mchunkptr remainder; /* remainder from a split */ + long remainder_size; /* its size */ + int remainder_index; /* its bin index */ + unsigned long block; /* block traverser bit */ + int startidx; /* first bin of a traversed block */ + mchunkptr fwd; /* misc temp for linking */ + mchunkptr bck; /* misc temp for linking */ + mbinptr q; /* misc temp */ + + INTERNAL_SIZE_T nb = request2size(bytes); /* padded request size; */ + + /* Check for overflow and just fail, if so. */ + if (nb > INT_MAX || nb < bytes) + { + RERRNO = ENOMEM; + return 0; + } + + MALLOC_LOCK; + + /* Check for exact match in a bin */ + + if (is_small_request(nb)) /* Faster version for small requests */ + { + idx = smallbin_index(nb); + + /* No traversal or size check necessary for small bins. */ + + q = bin_at(idx); + victim = last(q); + +#if MALLOC_ALIGN != 16 + /* Also scan the next one, since it would have a remainder < MINSIZE */ + if (victim == q) + { + q = next_bin(q); + victim = last(q); + } +#endif + if (victim != q) + { + victim_size = chunksize(victim); + unlink(victim, bck, fwd); + set_inuse_bit_at_offset(victim, victim_size); + check_malloced_chunk(victim, nb); + MALLOC_UNLOCK; + return chunk2mem(victim); + } + + idx += 2; /* Set for bin scan below. We've already scanned 2 bins. */ + + } + else + { + idx = bin_index(nb); + bin = bin_at(idx); + + for (victim = last(bin); victim != bin; victim = victim->bk) + { + victim_size = chunksize(victim); + remainder_size = long_sub_size_t(victim_size, nb); + + if (remainder_size >= (long)MINSIZE) /* too big */ + { + --idx; /* adjust to rescan below after checking last remainder */ + break; + } + + else if (remainder_size >= 0) /* exact fit */ + { + unlink(victim, bck, fwd); + set_inuse_bit_at_offset(victim, victim_size); + check_malloced_chunk(victim, nb); + MALLOC_UNLOCK; + return chunk2mem(victim); + } + } + + ++idx; + + } + + /* Try to use the last split-off remainder */ + + if ( (victim = last_remainder->fd) != last_remainder) + { + victim_size = chunksize(victim); + remainder_size = long_sub_size_t(victim_size, nb); + + if (remainder_size >= (long)MINSIZE) /* re-split */ + { + remainder = chunk_at_offset(victim, nb); + set_head(victim, nb | PREV_INUSE); + link_last_remainder(remainder); + set_head(remainder, remainder_size | PREV_INUSE); + set_foot(remainder, remainder_size); + check_malloced_chunk(victim, nb); + MALLOC_UNLOCK; + return chunk2mem(victim); + } + + clear_last_remainder; + + if (remainder_size >= 0) /* exhaust */ + { + set_inuse_bit_at_offset(victim, victim_size); + check_malloced_chunk(victim, nb); + MALLOC_UNLOCK; + return chunk2mem(victim); + } + + /* Else place in bin */ + + frontlink(victim, victim_size, remainder_index, bck, fwd); + } + + /* + If there are any possibly nonempty big-enough blocks, + search for best fitting chunk by scanning bins in blockwidth units. + */ + + if ( (block = idx2binblock(idx)) <= binblocks) + { + + /* Get to the first marked block */ + + if ( (block & binblocks) == 0) + { + /* force to an even block boundary */ + idx = (idx & ~(BINBLOCKWIDTH - 1)) + BINBLOCKWIDTH; + block <<= 1; + while ((block & binblocks) == 0) + { + idx += BINBLOCKWIDTH; + block <<= 1; + } + } + + /* For each possibly nonempty block ... */ + for (;;) + { + startidx = idx; /* (track incomplete blocks) */ + q = bin = bin_at(idx); + + /* For each bin in this block ... */ + do + { + /* Find and use first big enough chunk ... */ + + for (victim = last(bin); victim != bin; victim = victim->bk) + { + victim_size = chunksize(victim); + remainder_size = long_sub_size_t(victim_size, nb); + + if (remainder_size >= (long)MINSIZE) /* split */ + { + remainder = chunk_at_offset(victim, nb); + set_head(victim, nb | PREV_INUSE); + unlink(victim, bck, fwd); + link_last_remainder(remainder); + set_head(remainder, remainder_size | PREV_INUSE); + set_foot(remainder, remainder_size); + check_malloced_chunk(victim, nb); + MALLOC_UNLOCK; + return chunk2mem(victim); + } + + else if (remainder_size >= 0) /* take */ + { + set_inuse_bit_at_offset(victim, victim_size); + unlink(victim, bck, fwd); + check_malloced_chunk(victim, nb); + MALLOC_UNLOCK; + return chunk2mem(victim); + } + + } + + bin = next_bin(bin); + +#if MALLOC_ALIGN == 16 + if (idx < MAX_SMALLBIN) + { + bin = next_bin(bin); + ++idx; + } +#endif + } while ((++idx & (BINBLOCKWIDTH - 1)) != 0); + + /* Clear out the block bit. */ + + do /* Possibly backtrack to try to clear a partial block */ + { + if ((startidx & (BINBLOCKWIDTH - 1)) == 0) + { + binblocks &= ~block; + break; + } + --startidx; + q = prev_bin(q); + } while (first(q) == q); + + /* Get to the next possibly nonempty block */ + + if ( (block <<= 1) <= binblocks && (block != 0) ) + { + while ((block & binblocks) == 0) + { + idx += BINBLOCKWIDTH; + block <<= 1; + } + } + else + break; + } + } + + + /* Try to use top chunk */ + + /* Require that there be a remainder, ensuring top always exists */ + remainder_size = long_sub_size_t(chunksize(top), nb); + if (chunksize(top) < nb || remainder_size < (long)MINSIZE) + { + +#if HAVE_MMAP + /* If big and would otherwise need to extend, try to use mmap instead */ + if ((unsigned long)nb >= (unsigned long)mmap_threshold && + (victim = mmap_chunk(nb)) != 0) + { + MALLOC_UNLOCK; + return chunk2mem(victim); + } +#endif + + /* Try to extend */ + malloc_extend_top(RCALL nb); + remainder_size = long_sub_size_t(chunksize(top), nb); + if (chunksize(top) < nb || remainder_size < (long)MINSIZE) + { + MALLOC_UNLOCK; + return 0; /* propagate failure */ + } + } + + victim = top; + set_head(victim, nb | PREV_INUSE); + top = chunk_at_offset(victim, nb); + set_head(top, remainder_size | PREV_INUSE); + check_malloced_chunk(victim, nb); + MALLOC_UNLOCK; + return chunk2mem(victim); + +#endif /* MALLOC_PROVIDED */ +} + +#endif /* DEFINE_MALLOC */ + +#ifdef DEFINE_FREE + +/* + + free() algorithm : + + cases: + + 1. free(0) has no effect. + + 2. If the chunk was allocated via mmap, it is release via munmap(). + + 3. If a returned chunk borders the current high end of memory, + it is consolidated into the top, and if the total unused + topmost memory exceeds the trim threshold, malloc_trim is + called. + + 4. Other chunks are consolidated as they arrive, and + placed in corresponding bins. (This includes the case of + consolidating with the current `last_remainder'). + +*/ + + +#if __STD_C +void fREe(RARG Void_t* mem) +#else +void fREe(RARG mem) RDECL Void_t* mem; +#endif +{ +#ifdef MALLOC_PROVIDED + + free (mem); + +#else + + mchunkptr p; /* chunk corresponding to mem */ + INTERNAL_SIZE_T hd; /* its head field */ + INTERNAL_SIZE_T sz; /* its size */ + int idx; /* its bin index */ + mchunkptr next; /* next contiguous chunk */ + INTERNAL_SIZE_T nextsz; /* its size */ + INTERNAL_SIZE_T prevsz; /* size of previous contiguous chunk */ + mchunkptr bck; /* misc temp for linking */ + mchunkptr fwd; /* misc temp for linking */ + int islr; /* track whether merging with last_remainder */ + + if (mem == 0) /* free(0) has no effect */ + return; + + MALLOC_LOCK; + + p = mem2chunk(mem); + hd = p->size; + +#if HAVE_MMAP + if (hd & IS_MMAPPED) /* release mmapped memory. */ + { + munmap_chunk(p); + MALLOC_UNLOCK; + return; + } +#endif + + check_inuse_chunk(p); + + sz = hd & ~PREV_INUSE; + next = chunk_at_offset(p, sz); + nextsz = chunksize(next); + + if (next == top) /* merge with top */ + { + sz += nextsz; + + if (!(hd & PREV_INUSE)) /* consolidate backward */ + { + prevsz = p->prev_size; + p = chunk_at_offset(p, -prevsz); + sz += prevsz; + unlink(p, bck, fwd); + } + + set_head(p, sz | PREV_INUSE); + top = p; + if ((unsigned long)(sz) >= (unsigned long)trim_threshold) + malloc_trim(RCALL top_pad); + MALLOC_UNLOCK; + return; + } + + set_head(next, nextsz); /* clear inuse bit */ + + islr = 0; + + if (!(hd & PREV_INUSE)) /* consolidate backward */ + { + prevsz = p->prev_size; + p = chunk_at_offset(p, -prevsz); + sz += prevsz; + + if (p->fd == last_remainder) /* keep as last_remainder */ + islr = 1; + else + unlink(p, bck, fwd); + } + + if (!(inuse_bit_at_offset(next, nextsz))) /* consolidate forward */ + { + sz += nextsz; + + if (!islr && next->fd == last_remainder) /* re-insert last_remainder */ + { + islr = 1; + link_last_remainder(p); + } + else + unlink(next, bck, fwd); + } + + + set_head(p, sz | PREV_INUSE); + set_foot(p, sz); + if (!islr) + frontlink(p, sz, idx, bck, fwd); + + MALLOC_UNLOCK; + +#endif /* MALLOC_PROVIDED */ +} + +#endif /* DEFINE_FREE */ + +#ifdef DEFINE_REALLOC + +/* + + Realloc algorithm: + + Chunks that were obtained via mmap cannot be extended or shrunk + unless HAVE_MREMAP is defined, in which case mremap is used. + Otherwise, if their reallocation is for additional space, they are + copied. If for less, they are just left alone. + + Otherwise, if the reallocation is for additional space, and the + chunk can be extended, it is, else a malloc-copy-free sequence is + taken. There are several different ways that a chunk could be + extended. All are tried: + + * Extending forward into following adjacent free chunk. + * Shifting backwards, joining preceding adjacent space + * Both shifting backwards and extending forward. + * Extending into newly sbrked space + + Unless the #define REALLOC_ZERO_BYTES_FREES is set, realloc with a + size argument of zero (re)allocates a minimum-sized chunk. + + If the reallocation is for less space, and the new request is for + a `small' (<512 bytes) size, then the newly unused space is lopped + off and freed. + + The old unix realloc convention of allowing the last-free'd chunk + to be used as an argument to realloc is no longer supported. + I don't know of any programs still relying on this feature, + and allowing it would also allow too many other incorrect + usages of realloc to be sensible. + + +*/ + + +#if __STD_C +Void_t* rEALLOc(RARG Void_t* oldmem, size_t bytes) +#else +Void_t* rEALLOc(RARG oldmem, bytes) RDECL Void_t* oldmem; size_t bytes; +#endif +{ +#ifdef MALLOC_PROVIDED + + realloc (oldmem, bytes); + +#else + + INTERNAL_SIZE_T nb; /* padded request size */ + + mchunkptr oldp; /* chunk corresponding to oldmem */ + INTERNAL_SIZE_T oldsize; /* its size */ + + mchunkptr newp; /* chunk to return */ + INTERNAL_SIZE_T newsize; /* its size */ + Void_t* newmem; /* corresponding user mem */ + + mchunkptr next; /* next contiguous chunk after oldp */ + INTERNAL_SIZE_T nextsize; /* its size */ + + mchunkptr prev; /* previous contiguous chunk before oldp */ + INTERNAL_SIZE_T prevsize; /* its size */ + + mchunkptr remainder; /* holds split off extra space from newp */ + INTERNAL_SIZE_T remainder_size; /* its size */ + + mchunkptr bck; /* misc temp for linking */ + mchunkptr fwd; /* misc temp for linking */ + +#ifdef REALLOC_ZERO_BYTES_FREES + if (bytes == 0) { fREe(RCALL oldmem); return 0; } +#endif + + + /* realloc of null is supposed to be same as malloc */ + if (oldmem == 0) return mALLOc(RCALL bytes); + + MALLOC_LOCK; + + newp = oldp = mem2chunk(oldmem); + newsize = oldsize = chunksize(oldp); + + + nb = request2size(bytes); + + /* Check for overflow and just fail, if so. */ + if (nb > INT_MAX || nb < bytes) + { + RERRNO = ENOMEM; + return 0; + } + +#if HAVE_MMAP + if (chunk_is_mmapped(oldp)) + { +#if HAVE_MREMAP + newp = mremap_chunk(oldp, nb); + if(newp) + { + MALLOC_UNLOCK; + return chunk2mem(newp); + } +#endif + /* Note the extra SIZE_SZ overhead. */ + if(oldsize - SIZE_SZ >= nb) + { + MALLOC_UNLOCK; + return oldmem; /* do nothing */ + } + /* Must alloc, copy, free. */ + newmem = mALLOc(RCALL bytes); + if (newmem == 0) + { + MALLOC_UNLOCK; + return 0; /* propagate failure */ + } + MALLOC_COPY(newmem, oldmem, oldsize - 2*SIZE_SZ); + munmap_chunk(oldp); + MALLOC_UNLOCK; + return newmem; + } +#endif + + check_inuse_chunk(oldp); + + if ((long)(oldsize) < (long)(nb)) + { + + /* Try expanding forward */ + + next = chunk_at_offset(oldp, oldsize); + if (next == top || !inuse(next)) + { + nextsize = chunksize(next); + + /* Forward into top only if a remainder */ + if (next == top) + { + if ((long)(nextsize + newsize) >= (long)(nb + MINSIZE)) + { + newsize += nextsize; + top = chunk_at_offset(oldp, nb); + set_head(top, (newsize - nb) | PREV_INUSE); + set_head_size(oldp, nb); + MALLOC_UNLOCK; + return chunk2mem(oldp); + } + } + + /* Forward into next chunk */ + else if (((long)(nextsize + newsize) >= (long)(nb))) + { + unlink(next, bck, fwd); + newsize += nextsize; + goto split; + } + } + else + { + next = 0; + nextsize = 0; + } + + /* Try shifting backwards. */ + + if (!prev_inuse(oldp)) + { + prev = prev_chunk(oldp); + prevsize = chunksize(prev); + + /* try forward + backward first to save a later consolidation */ + + if (next != 0) + { + /* into top */ + if (next == top) + { + if ((long)(nextsize + prevsize + newsize) >= (long)(nb + MINSIZE)) + { + unlink(prev, bck, fwd); + newp = prev; + newsize += prevsize + nextsize; + newmem = chunk2mem(newp); + MALLOC_COPY(newmem, oldmem, oldsize - SIZE_SZ); + top = chunk_at_offset(newp, nb); + set_head(top, (newsize - nb) | PREV_INUSE); + set_head_size(newp, nb); + MALLOC_UNLOCK; + return newmem; + } + } + + /* into next chunk */ + else if (((long)(nextsize + prevsize + newsize) >= (long)(nb))) + { + unlink(next, bck, fwd); + unlink(prev, bck, fwd); + newp = prev; + newsize += nextsize + prevsize; + newmem = chunk2mem(newp); + MALLOC_COPY(newmem, oldmem, oldsize - SIZE_SZ); + goto split; + } + } + + /* backward only */ + if (prev != 0 && (long)(prevsize + newsize) >= (long)nb) + { + unlink(prev, bck, fwd); + newp = prev; + newsize += prevsize; + newmem = chunk2mem(newp); + MALLOC_COPY(newmem, oldmem, oldsize - SIZE_SZ); + goto split; + } + } + + /* Must allocate */ + + newmem = mALLOc (RCALL bytes); + + if (newmem == 0) /* propagate failure */ + { + MALLOC_UNLOCK; + return 0; + } + + /* Avoid copy if newp is next chunk after oldp. */ + /* (This can only happen when new chunk is sbrk'ed.) */ + + if ( (newp = mem2chunk(newmem)) == next_chunk(oldp)) + { + newsize += chunksize(newp); + newp = oldp; + goto split; + } + + /* Otherwise copy, free, and exit */ + MALLOC_COPY(newmem, oldmem, oldsize - SIZE_SZ); + fREe(RCALL oldmem); + MALLOC_UNLOCK; + return newmem; + } + + + split: /* split off extra room in old or expanded chunk */ + + remainder_size = long_sub_size_t(newsize, nb); + + if (remainder_size >= (long)MINSIZE) /* split off remainder */ + { + remainder = chunk_at_offset(newp, nb); + set_head_size(newp, nb); + set_head(remainder, remainder_size | PREV_INUSE); + set_inuse_bit_at_offset(remainder, remainder_size); + fREe(RCALL chunk2mem(remainder)); /* let free() deal with it */ + } + else + { + set_head_size(newp, newsize); + set_inuse_bit_at_offset(newp, newsize); + } + + check_inuse_chunk(newp); + MALLOC_UNLOCK; + return chunk2mem(newp); + +#endif /* MALLOC_PROVIDED */ +} + +#endif /* DEFINE_REALLOC */ + +#ifdef DEFINE_MEMALIGN + +/* + + memalign algorithm: + + memalign requests more than enough space from malloc, finds a spot + within that chunk that meets the alignment request, and then + possibly frees the leading and trailing space. + + The alignment argument must be a power of two. This property is not + checked by memalign, so misuse may result in random runtime errors. + + 8-byte alignment is guaranteed by normal malloc calls, so don't + bother calling memalign with an argument of 8 or less. + + Overreliance on memalign is a sure way to fragment space. + +*/ + + +#if __STD_C +Void_t* mEMALIGn(RARG size_t alignment, size_t bytes) +#else +Void_t* mEMALIGn(RARG alignment, bytes) RDECL size_t alignment; size_t bytes; +#endif +{ + INTERNAL_SIZE_T nb; /* padded request size */ + char* m; /* memory returned by malloc call */ + mchunkptr p; /* corresponding chunk */ + char* brk; /* alignment point within p */ + mchunkptr newp; /* chunk to return */ + INTERNAL_SIZE_T newsize; /* its size */ + INTERNAL_SIZE_T leadsize; /* leading space befor alignment point */ + mchunkptr remainder; /* spare room at end to split off */ + long remainder_size; /* its size */ + + /* If need less alignment than we give anyway, just relay to malloc */ + + if (alignment <= MALLOC_ALIGNMENT) return mALLOc(RCALL bytes); + + /* Otherwise, ensure that it is at least a minimum chunk size */ + + if (alignment < MINSIZE) alignment = MINSIZE; + + /* Call malloc with worst case padding to hit alignment. */ + + nb = request2size(bytes); + + /* Check for overflow. */ + if (nb > __SIZE_MAX__ - (alignment + MINSIZE) || nb < bytes) + { + RERRNO = ENOMEM; + return 0; + } + + m = (char*)(mALLOc(RCALL nb + alignment + MINSIZE)); + + if (m == 0) return 0; /* propagate failure */ + + MALLOC_LOCK; + + p = mem2chunk(m); + + if ((((unsigned long)(m)) % alignment) == 0) /* aligned */ + { +#if HAVE_MMAP + if(chunk_is_mmapped(p)) + { + MALLOC_UNLOCK; + return chunk2mem(p); /* nothing more to do */ + } +#endif + } + else /* misaligned */ + { + /* + Find an aligned spot inside chunk. + Since we need to give back leading space in a chunk of at + least MINSIZE, if the first calculation places us at + a spot with less than MINSIZE leader, we can move to the + next aligned spot -- we've allocated enough total room so that + this is always possible. + */ + + brk = (char*)mem2chunk(((unsigned long)(m + alignment - 1)) & -alignment); + if ((long)(brk - (char*)(p)) < (long)MINSIZE) brk = brk + alignment; + + newp = (mchunkptr)brk; + leadsize = brk - (char*)(p); + newsize = chunksize(p) - leadsize; + +#if HAVE_MMAP + if(chunk_is_mmapped(p)) + { + newp->prev_size = p->prev_size + leadsize; + set_head(newp, newsize|IS_MMAPPED); + MALLOC_UNLOCK; + return chunk2mem(newp); + } +#endif + + /* give back leader, use the rest */ + + set_head(newp, newsize | PREV_INUSE); + set_inuse_bit_at_offset(newp, newsize); + set_head_size(p, leadsize); + fREe(RCALL chunk2mem(p)); + p = newp; + + assert (newsize >= nb && (((unsigned long)(chunk2mem(p))) % alignment) == 0); + } + + /* Also give back spare room at the end */ + + remainder_size = long_sub_size_t(chunksize(p), nb); + + if (remainder_size >= (long)MINSIZE) + { + remainder = chunk_at_offset(p, nb); + set_head(remainder, remainder_size | PREV_INUSE); + set_head_size(p, nb); + fREe(RCALL chunk2mem(remainder)); + } + + check_inuse_chunk(p); + MALLOC_UNLOCK; + return chunk2mem(p); + +} + +#endif /* DEFINE_MEMALIGN */ + +#ifdef DEFINE_VALLOC + +/* + valloc just invokes memalign with alignment argument equal + to the page size of the system (or as near to this as can + be figured out from all the includes/defines above.) +*/ + +#if __STD_C +Void_t* vALLOc(RARG size_t bytes) +#else +Void_t* vALLOc(RARG bytes) RDECL size_t bytes; +#endif +{ + return mEMALIGn (RCALL malloc_getpagesize, bytes); +} + +#endif /* DEFINE_VALLOC */ + +#ifdef DEFINE_PVALLOC + +/* + pvalloc just invokes valloc for the nearest pagesize + that will accommodate request +*/ + + +#if __STD_C +Void_t* pvALLOc(RARG size_t bytes) +#else +Void_t* pvALLOc(RARG bytes) RDECL size_t bytes; +#endif +{ + size_t pagesize = malloc_getpagesize; + if (bytes > __SIZE_MAX__ - pagesize) + { + RERRNO = ENOMEM; + return 0; + } + return mEMALIGn (RCALL pagesize, (bytes + pagesize - 1) & ~(pagesize - 1)); +} + +#endif /* DEFINE_PVALLOC */ + +#ifdef DEFINE_CALLOC + +/* + + calloc calls malloc, then zeroes out the allocated chunk. + +*/ + +#if __STD_C +Void_t* cALLOc(RARG size_t n, size_t elem_size) +#else +Void_t* cALLOc(RARG n, elem_size) RDECL size_t n; size_t elem_size; +#endif +{ + mchunkptr p; + INTERNAL_SIZE_T csz; + + INTERNAL_SIZE_T sz; + +#if MORECORE_CLEARS + mchunkptr oldtop; + INTERNAL_SIZE_T oldtopsize; +#endif + Void_t* mem; + + if (__builtin_mul_overflow((INTERNAL_SIZE_T) n, (INTERNAL_SIZE_T) elem_size, &sz)) + { + errno = ENOMEM; + return 0; + } + + /* check if expand_top called, in which case don't need to clear */ +#if MORECORE_CLEARS + MALLOC_LOCK; + oldtop = top; + oldtopsize = chunksize(top); +#endif + + mem = mALLOc (RCALL sz); + + if (mem == 0) + { +#if MORECORE_CLEARS + MALLOC_UNLOCK; +#endif + return 0; + } + else + { + p = mem2chunk(mem); + + /* Two optional cases in which clearing not necessary */ + + +#if HAVE_MMAP + if (chunk_is_mmapped(p)) + { +#if MORECORE_CLEARS + MALLOC_UNLOCK; +#endif + return mem; + } +#endif + + csz = chunksize(p); + +#if MORECORE_CLEARS + if (p == oldtop && csz > oldtopsize) + { + /* clear only the bytes from non-freshly-sbrked memory */ + csz = oldtopsize; + } + MALLOC_UNLOCK; +#endif + + MALLOC_ZERO(mem, csz - SIZE_SZ); + return mem; + } +} + +#endif /* DEFINE_CALLOC */ + +#if defined(DEFINE_CFREE) && !defined(__CYGWIN__) + +/* + + cfree just calls free. It is needed/defined on some systems + that pair it with calloc, presumably for odd historical reasons. + +*/ + +#if !defined(INTERNAL_LINUX_C_LIB) || !defined(__ELF__) +#if !defined(_LIBC) || !defined(_REENT_ONLY) +#if __STD_C +void cfree(Void_t *mem) +#else +void cfree(mem) Void_t *mem; +#endif +{ +#ifdef _LIBC + fREe(_REENT, mem); +#else + fREe(mem); +#endif +} +#endif +#endif + +#endif /* DEFINE_CFREE */ + +#ifdef DEFINE_FREE + +/* + + Malloc_trim gives memory back to the system (via negative + arguments to sbrk) if there is unused memory at the `high' end of + the malloc pool. You can call this after freeing large blocks of + memory to potentially reduce the system-level memory requirements + of a program. However, it cannot guarantee to reduce memory. Under + some allocation patterns, some large free blocks of memory will be + locked between two used chunks, so they cannot be given back to + the system. + + The `pad' argument to malloc_trim represents the amount of free + trailing space to leave untrimmed. If this argument is zero, + only the minimum amount of memory to maintain internal data + structures will be left (one page or less). Non-zero arguments + can be supplied to maintain enough trailing space to service + future expected allocations without having to re-obtain memory + from the system. + + Malloc_trim returns 1 if it actually released any memory, else 0. + +*/ + +#if __STD_C +int malloc_trim(RARG size_t pad) +#else +int malloc_trim(RARG pad) RDECL size_t pad; +#endif +{ + long top_size; /* Amount of top-most memory */ + long extra; /* Amount to release */ + char* current_brk; /* address returned by pre-check sbrk call */ + char* new_brk; /* address returned by negative sbrk call */ + + unsigned long pagesz = malloc_getpagesize; + + MALLOC_LOCK; + + top_size = chunksize(top); + extra = ((top_size - pad - MINSIZE + (pagesz-1)) / pagesz - 1) * pagesz; + + if (extra < (long)pagesz) /* Not enough memory to release */ + { + MALLOC_UNLOCK; + return 0; + } + + else + { + /* Test to make sure no one else called sbrk */ + current_brk = (char*)(MORECORE (0)); + if (current_brk != (char*)(top) + top_size) + { + MALLOC_UNLOCK; + return 0; /* Apparently we don't own memory; must fail */ + } + + else + { + new_brk = (char*)(MORECORE (-extra)); + + if (new_brk == (char*)(MORECORE_FAILURE)) /* sbrk failed? */ + { + /* Try to figure out what we have */ + current_brk = (char*)(MORECORE (0)); + top_size = current_brk - (char*)top; + if (top_size >= (long)MINSIZE) /* if not, we are very very dead! */ + { + sbrked_mem = current_brk - sbrk_base; + set_head(top, top_size | PREV_INUSE); + } + check_chunk(top); + MALLOC_UNLOCK; + return 0; + } + + else + { + /* Success. Adjust top accordingly. */ + set_head(top, (top_size - extra) | PREV_INUSE); + sbrked_mem -= extra; + check_chunk(top); + MALLOC_UNLOCK; + return 1; + } + } + } +} + +#endif /* DEFINE_FREE */ + +#ifdef DEFINE_MALLOC_USABLE_SIZE + +/* + malloc_usable_size: + + This routine tells you how many bytes you can actually use in an + allocated chunk, which may be more than you requested (although + often not). You can use this many bytes without worrying about + overwriting other allocated objects. Not a particularly great + programming practice, but still sometimes useful. + +*/ + +#if __STD_C +size_t malloc_usable_size(RARG Void_t* mem) +#else +size_t malloc_usable_size(RARG mem) RDECL Void_t* mem; +#endif +{ + mchunkptr p; + if (mem == 0) + return 0; + else + { + p = mem2chunk(mem); + if(!chunk_is_mmapped(p)) + { + if (!inuse(p)) return 0; +#if DEBUG + MALLOC_LOCK; + check_inuse_chunk(p); + MALLOC_UNLOCK; +#endif + return chunksize(p) - SIZE_SZ; + } + return chunksize(p) - 2*SIZE_SZ; + } +} + +#endif /* DEFINE_MALLOC_USABLE_SIZE */ + +#ifdef DEFINE_MALLINFO + +/* Utility to update current_mallinfo for malloc_stats and mallinfo() */ + +STATIC void malloc_update_mallinfo() +{ + int i; + mbinptr b; + mchunkptr p; +#if DEBUG + mchunkptr q; +#endif + + INTERNAL_SIZE_T avail = chunksize(top); + int navail = ((long)(avail) >= (long)MINSIZE)? 1 : 0; + + for (i = 1; i < NAV; ++i) + { + b = bin_at(i); + for (p = last(b); p != b; p = p->bk) + { +#if DEBUG + check_free_chunk(p); + for (q = next_chunk(p); + q < top && inuse(q) && (long)(chunksize(q)) >= (long)MINSIZE; + q = next_chunk(q)) + check_inuse_chunk(q); +#endif + avail += chunksize(p); + navail++; + } + } + + current_mallinfo.ordblks = navail; + current_mallinfo.uordblks = sbrked_mem - avail; + current_mallinfo.fordblks = avail; +#if HAVE_MMAP + current_mallinfo.hblks = n_mmaps; + current_mallinfo.hblkhd = mmapped_mem; +#endif + current_mallinfo.keepcost = chunksize(top); + +} + +#else /* ! DEFINE_MALLINFO */ + +#if __STD_C +extern void malloc_update_mallinfo(void); +#else +extern void malloc_update_mallinfo(); +#endif + +#endif /* ! DEFINE_MALLINFO */ + +#ifdef DEFINE_MALLOC_STATS + +/* + + malloc_stats: + + Prints on stderr the amount of space obtain from the system (both + via sbrk and mmap), the maximum amount (which may be more than + current if malloc_trim and/or munmap got called), the maximum + number of simultaneous mmap regions used, and the current number + of bytes allocated via malloc (or realloc, etc) but not yet + freed. (Note that this is the number of bytes allocated, not the + number requested. It will be larger than the number requested + because of alignment and bookkeeping overhead.) + +*/ + +#if __STD_C +void malloc_stats(RONEARG) +#else +void malloc_stats(RONEARG) RDECL +#endif +{ + unsigned long local_max_total_mem; + int local_sbrked_mem; + struct mallinfo local_mallinfo; +#if HAVE_MMAP + unsigned long local_mmapped_mem, local_max_n_mmaps; +#endif + FILE *fp; + + MALLOC_LOCK; + malloc_update_mallinfo(); + local_max_total_mem = max_total_mem; + local_sbrked_mem = sbrked_mem; + local_mallinfo = current_mallinfo; +#if HAVE_MMAP + local_mmapped_mem = mmapped_mem; + local_max_n_mmaps = max_n_mmaps; +#endif + MALLOC_UNLOCK; + +#ifdef _LIBC + _REENT_SMALL_CHECK_INIT(reent_ptr); + fp = _stderr_r(reent_ptr); +#define fprintf fiprintf +#else + fp = stderr; +#endif + + fprintf(fp, "max system bytes = %10u\n", + (unsigned int)(local_max_total_mem)); +#if HAVE_MMAP + fprintf(fp, "system bytes = %10u\n", + (unsigned int)(local_sbrked_mem + local_mmapped_mem)); + fprintf(fp, "in use bytes = %10u\n", + (unsigned int)(local_mallinfo.uordblks + local_mmapped_mem)); +#else + fprintf(fp, "system bytes = %10u\n", + (unsigned int)local_sbrked_mem); + fprintf(fp, "in use bytes = %10u\n", + (unsigned int)local_mallinfo.uordblks); +#endif +#if HAVE_MMAP + fprintf(fp, "max mmap regions = %10u\n", + (unsigned int)local_max_n_mmaps); +#endif +} + +#endif /* DEFINE_MALLOC_STATS */ + +#ifdef DEFINE_MALLINFO + +/* + mallinfo returns a copy of updated current mallinfo. +*/ + +#if __STD_C +struct mallinfo mALLINFo(RONEARG) +#else +struct mallinfo mALLINFo(RONEARG) RDECL +#endif +{ + struct mallinfo ret; + + MALLOC_LOCK; + malloc_update_mallinfo(); + ret = current_mallinfo; + MALLOC_UNLOCK; + return ret; +} + +#endif /* DEFINE_MALLINFO */ + +#ifdef DEFINE_MALLOPT + +/* + mallopt: + + mallopt is the general SVID/XPG interface to tunable parameters. + The format is to provide a (parameter-number, parameter-value) pair. + mallopt then sets the corresponding parameter to the argument + value if it can (i.e., so long as the value is meaningful), + and returns 1 if successful else 0. + + See descriptions of tunable parameters above. + +*/ + +#if __STD_C +int mALLOPt(RARG int param_number, int value) +#else +int mALLOPt(RARG param_number, value) RDECL int param_number; int value; +#endif +{ + MALLOC_LOCK; + switch(param_number) + { + case M_TRIM_THRESHOLD: + trim_threshold = value; MALLOC_UNLOCK; return 1; + case M_TOP_PAD: + top_pad = value; MALLOC_UNLOCK; return 1; + case M_MMAP_THRESHOLD: +#if HAVE_MMAP + mmap_threshold = value; +#endif + MALLOC_UNLOCK; + return 1; + case M_MMAP_MAX: +#if HAVE_MMAP + n_mmaps_max = value; MALLOC_UNLOCK; return 1; +#else + MALLOC_UNLOCK; return value == 0; +#endif + + default: + MALLOC_UNLOCK; + return 0; + } +} + +#endif /* DEFINE_MALLOPT */ + +/* + +History: + + V2.6.5 Wed Jun 17 15:57:31 1998 Doug Lea (dl at gee) + * Fixed ordering problem with boundary-stamping + + V2.6.3 Sun May 19 08:17:58 1996 Doug Lea (dl at gee) + * Added pvalloc, as recommended by H.J. Liu + * Added 64bit pointer support mainly from Wolfram Gloger + * Added anonymously donated WIN32 sbrk emulation + * Malloc, calloc, getpagesize: add optimizations from Raymond Nijssen + * malloc_extend_top: fix mask error that caused wastage after + foreign sbrks + * Add linux mremap support code from HJ Liu + + V2.6.2 Tue Dec 5 06:52:55 1995 Doug Lea (dl at gee) + * Integrated most documentation with the code. + * Add support for mmap, with help from + Wolfram Gloger (Gloger@lrz.uni-muenchen.de). + * Use last_remainder in more cases. + * Pack bins using idea from colin@nyx10.cs.du.edu + * Use ordered bins instead of best-fit threshhold + * Eliminate block-local decls to simplify tracing and debugging. + * Support another case of realloc via move into top + * Fix error occuring when initial sbrk_base not word-aligned. + * Rely on page size for units instead of SBRK_UNIT to + avoid surprises about sbrk alignment conventions. + * Add mallinfo, mallopt. Thanks to Raymond Nijssen + (raymond@es.ele.tue.nl) for the suggestion. + * Add `pad' argument to malloc_trim and top_pad mallopt parameter. + * More precautions for cases where other routines call sbrk, + courtesy of Wolfram Gloger (Gloger@lrz.uni-muenchen.de). + * Added macros etc., allowing use in linux libc from + H.J. Lu (hjl@gnu.ai.mit.edu) + * Inverted this history list + + V2.6.1 Sat Dec 2 14:10:57 1995 Doug Lea (dl at gee) + * Re-tuned and fixed to behave more nicely with V2.6.0 changes. + * Removed all preallocation code since under current scheme + the work required to undo bad preallocations exceeds + the work saved in good cases for most test programs. + * No longer use return list or unconsolidated bins since + no scheme using them consistently outperforms those that don't + given above changes. + * Use best fit for very large chunks to prevent some worst-cases. + * Added some support for debugging + + V2.6.0 Sat Nov 4 07:05:23 1995 Doug Lea (dl at gee) + * Removed footers when chunks are in use. Thanks to + Paul Wilson (wilson@cs.texas.edu) for the suggestion. + + V2.5.4 Wed Nov 1 07:54:51 1995 Doug Lea (dl at gee) + * Added malloc_trim, with help from Wolfram Gloger + (wmglo@Dent.MED.Uni-Muenchen.DE). + + V2.5.3 Tue Apr 26 10:16:01 1994 Doug Lea (dl at g) + + V2.5.2 Tue Apr 5 16:20:40 1994 Doug Lea (dl at g) + * realloc: try to expand in both directions + * malloc: swap order of clean-bin strategy; + * realloc: only conditionally expand backwards + * Try not to scavenge used bins + * Use bin counts as a guide to preallocation + * Occasionally bin return list chunks in first scan + * Add a few optimizations from colin@nyx10.cs.du.edu + + V2.5.1 Sat Aug 14 15:40:43 1993 Doug Lea (dl at g) + * faster bin computation & slightly different binning + * merged all consolidations to one part of malloc proper + (eliminating old malloc_find_space & malloc_clean_bin) + * Scan 2 returns chunks (not just 1) + * Propagate failure in realloc if malloc returns 0 + * Add stuff to allow compilation on non-ANSI compilers + from kpv@research.att.com + + V2.5 Sat Aug 7 07:41:59 1993 Doug Lea (dl at g.oswego.edu) + * removed potential for odd address access in prev_chunk + * removed dependency on getpagesize.h + * misc cosmetics and a bit more internal documentation + * anticosmetics: mangled names in macros to evade debugger strangeness + * tested on sparc, hp-700, dec-mips, rs6000 + with gcc & native cc (hp, dec only) allowing + Detlefs & Zorn comparison study (in SIGPLAN Notices.) + + Trial version Fri Aug 28 13:14:29 1992 Doug Lea (dl at g.oswego.edu) + * Based loosely on libg++-1.2X malloc. (It retains some of the overall + structure of old version, but most details differ.) + +*/ +#endif diff --git a/newlib/libc/stdlib/mallocr.c b/newlib/libc/stdlib/mallocr.c deleted file mode 100644 index 4b53997..0000000 --- a/newlib/libc/stdlib/mallocr.c +++ /dev/null @@ -1,3719 +0,0 @@ -#include -#ifdef MALLOC_PROVIDED -int _dummy_mallocr = 1; -#elif defined(_NANO_MALLOC) -# include "nano-mallocr.c" -#else -/* ---------- To make a malloc.h, start cutting here ------------ */ - -/* - A version of malloc/free/realloc written by Doug Lea and released to the - public domain. Send questions/comments/complaints/performance data - to dl@cs.oswego.edu - -* VERSION 2.6.5 Wed Jun 17 15:55:16 1998 Doug Lea (dl at gee) - - Note: There may be an updated version of this malloc obtainable at - ftp://g.oswego.edu/pub/misc/malloc.c - Check before installing! - - Note: This version differs from 2.6.4 only by correcting a - statement ordering error that could cause failures only - when calls to this malloc are interposed with calls to - other memory allocators. - -* Why use this malloc? - - This is not the fastest, most space-conserving, most portable, or - most tunable malloc ever written. However it is among the fastest - while also being among the most space-conserving, portable and tunable. - Consistent balance across these factors results in a good general-purpose - allocator. For a high-level description, see - http://g.oswego.edu/dl/html/malloc.html - -* Synopsis of public routines - - (Much fuller descriptions are contained in the program documentation below.) - - malloc(size_t n); - Return a pointer to a newly allocated chunk of at least n bytes, or null - if no space is available. - free(Void_t* p); - Release the chunk of memory pointed to by p, or no effect if p is null. - realloc(Void_t* p, size_t n); - Return a pointer to a chunk of size n that contains the same data - as does chunk p up to the minimum of (n, p's size) bytes, or null - if no space is available. The returned pointer may or may not be - the same as p. If p is null, equivalent to malloc. Unless the - #define REALLOC_ZERO_BYTES_FREES below is set, realloc with a - size argument of zero (re)allocates a minimum-sized chunk. - memalign(size_t alignment, size_t n); - Return a pointer to a newly allocated chunk of n bytes, aligned - in accord with the alignment argument, which must be a power of - two. - valloc(size_t n); - Equivalent to memalign(pagesize, n), where pagesize is the page - size of the system (or as near to this as can be figured out from - all the includes/defines below.) - pvalloc(size_t n); - Equivalent to valloc(minimum-page-that-holds(n)), that is, - round up n to nearest pagesize. - calloc(size_t unit, size_t quantity); - Returns a pointer to quantity * unit bytes, with all locations - set to zero. - cfree(Void_t* p); - Equivalent to free(p). - malloc_trim(size_t pad); - Release all but pad bytes of freed top-most memory back - to the system. Return 1 if successful, else 0. - malloc_usable_size(Void_t* p); - Report the number usable allocated bytes associated with allocated - chunk p. This may or may not report more bytes than were requested, - due to alignment and minimum size constraints. - malloc_stats(); - Prints brief summary statistics on stderr. - mallinfo() - Returns (by copy) a struct containing various summary statistics. - mallopt(int parameter_number, int parameter_value) - Changes one of the tunable parameters described below. Returns - 1 if successful in changing the parameter, else 0. - -* Vital statistics: - - Alignment: 8-byte - 8 byte alignment is currently hardwired into the design. This - seems to suffice for all current machines and C compilers. - - Assumed pointer representation: 4 or 8 bytes - Code for 8-byte pointers is untested by me but has worked - reliably by Wolfram Gloger, who contributed most of the - changes supporting this. - - Assumed size_t representation: 4 or 8 bytes - Note that size_t is allowed to be 4 bytes even if pointers are 8. - - Minimum overhead per allocated chunk: 4 or 8 bytes - Each malloced chunk has a hidden overhead of 4 bytes holding size - and status information. - - Minimum allocated size: 4-byte ptrs: 16 bytes (including 4 overhead) - 8-byte ptrs: 24/32 bytes (including, 4/8 overhead) - - When a chunk is freed, 12 (for 4byte ptrs) or 20 (for 8 byte - ptrs but 4 byte size) or 24 (for 8/8) additional bytes are - needed; 4 (8) for a trailing size field - and 8 (16) bytes for free list pointers. Thus, the minimum - allocatable size is 16/24/32 bytes. - - Even a request for zero bytes (i.e., malloc(0)) returns a - pointer to something of the minimum allocatable size. - - Maximum allocated size: 4-byte size_t: 2^31 - 8 bytes - 8-byte size_t: 2^63 - 16 bytes - - It is assumed that (possibly signed) size_t bit values suffice to - represent chunk sizes. `Possibly signed' is due to the fact - that `size_t' may be defined on a system as either a signed or - an unsigned type. To be conservative, values that would appear - as negative numbers are avoided. - Requests for sizes with a negative sign bit will return a - minimum-sized chunk. - - Maximum overhead wastage per allocated chunk: normally 15 bytes - - Alignnment demands, plus the minimum allocatable size restriction - make the normal worst-case wastage 15 bytes (i.e., up to 15 - more bytes will be allocated than were requested in malloc), with - two exceptions: - 1. Because requests for zero bytes allocate non-zero space, - the worst case wastage for a request of zero bytes is 24 bytes. - 2. For requests >= mmap_threshold that are serviced via - mmap(), the worst case wastage is 8 bytes plus the remainder - from a system page (the minimal mmap unit); typically 4096 bytes. - -* Limitations - - Here are some features that are NOT currently supported - - * No user-definable hooks for callbacks and the like. - * No automated mechanism for fully checking that all accesses - to malloced memory stay within their bounds. - * No support for compaction. - -* Synopsis of compile-time options: - - People have reported using previous versions of this malloc on all - versions of Unix, sometimes by tweaking some of the defines - below. It has been tested most extensively on Solaris and - Linux. It is also reported to work on WIN32 platforms. - People have also reported adapting this malloc for use in - stand-alone embedded systems. - - The implementation is in straight, hand-tuned ANSI C. Among other - consequences, it uses a lot of macros. Because of this, to be at - all usable, this code should be compiled using an optimizing compiler - (for example gcc -O2) that can simplify expressions and control - paths. - - __STD_C (default: derived from C compiler defines) - Nonzero if using ANSI-standard C compiler, a C++ compiler, or - a C compiler sufficiently close to ANSI to get away with it. - DEBUG (default: NOT defined) - Define to enable debugging. Adds fairly extensive assertion-based - checking to help track down memory errors, but noticeably slows down - execution. - SEPARATE_OBJECTS (default: NOT defined) - Define this to compile into separate .o files. You must then - compile malloc.c several times, defining a DEFINE_* macro each - time. The list of DEFINE_* macros appears below. - MALLOC_LOCK (default: NOT defined) - MALLOC_UNLOCK (default: NOT defined) - Define these to C expressions which are run to lock and unlock - the malloc data structures. Calls may be nested; that is, - MALLOC_LOCK may be called more than once before the corresponding - MALLOC_UNLOCK calls. MALLOC_LOCK must avoid waiting for a lock - that it already holds. - MALLOC_ALIGNMENT (default: NOT defined) - Define this to 16 if you need 16 byte alignment instead of 8 byte alignment - which is the normal default. - REALLOC_ZERO_BYTES_FREES (default: NOT defined) - Define this if you think that realloc(p, 0) should be equivalent - to free(p). Otherwise, since malloc returns a unique pointer for - malloc(0), so does realloc(p, 0). - HAVE_MEMCPY (default: defined) - Define if you are not otherwise using ANSI STD C, but still - have memcpy and memset in your C library and want to use them. - Otherwise, simple internal versions are supplied. - USE_MEMCPY (default: 1 if HAVE_MEMCPY is defined, 0 otherwise) - Define as 1 if you want the C library versions of memset and - memcpy called in realloc and calloc (otherwise macro versions are used). - At least on some platforms, the simple macro versions usually - outperform libc versions. - HAVE_MMAP (default: defined as 1) - Define to non-zero to optionally make malloc() use mmap() to - allocate very large blocks. - HAVE_MREMAP (default: defined as 0 unless Linux libc set) - Define to non-zero to optionally make realloc() use mremap() to - reallocate very large blocks. - malloc_getpagesize (default: derived from system #includes) - Either a constant or routine call returning the system page size. - HAVE_USR_INCLUDE_MALLOC_H (default: NOT defined) - Optionally define if you are on a system with a /usr/include/malloc.h - that declares struct mallinfo. It is not at all necessary to - define this even if you do, but will ensure consistency. - INTERNAL_SIZE_T (default: size_t) - Define to a 32-bit type (probably `unsigned int') if you are on a - 64-bit machine, yet do not want or need to allow malloc requests of - greater than 2^31 to be handled. This saves space, especially for - very small chunks. - INTERNAL_LINUX_C_LIB (default: NOT defined) - Defined only when compiled as part of Linux libc. - Also note that there is some odd internal name-mangling via defines - (for example, internally, `malloc' is named `mALLOc') needed - when compiling in this case. These look funny but don't otherwise - affect anything. - _LIBC (default: NOT defined) - Defined only when compiled as part of the Cygnus newlib - distribution. - WIN32 (default: undefined) - Define this on MS win (95, nt) platforms to compile in sbrk emulation. - LACKS_UNISTD_H (default: undefined) - Define this if your system does not have a . - MORECORE (default: sbrk) - The name of the routine to call to obtain more memory from the system. - MORECORE_FAILURE (default: -1) - The value returned upon failure of MORECORE. - MORECORE_CLEARS (default 1) - True (1) if the routine mapped to MORECORE zeroes out memory (which - holds for sbrk). - DEFAULT_TRIM_THRESHOLD - DEFAULT_TOP_PAD - DEFAULT_MMAP_THRESHOLD - DEFAULT_MMAP_MAX - Default values of tunable parameters (described in detail below) - controlling interaction with host system routines (sbrk, mmap, etc). - These values may also be changed dynamically via mallopt(). The - preset defaults are those that give best performance for typical - programs/systems. - - -*/ - - - - -/* Preliminaries */ - -#ifndef __STD_C -#ifdef __STDC__ -#define __STD_C 1 -#else -#if __cplusplus -#define __STD_C 1 -#else -#define __STD_C 0 -#endif /*__cplusplus*/ -#endif /*__STDC__*/ -#endif /*__STD_C*/ - -#ifndef Void_t -#if __STD_C -#define Void_t void -#else -#define Void_t char -#endif -#endif /*Void_t*/ - -#if __STD_C -#include /* for size_t */ -#else -#include -#endif - -#ifdef __cplusplus -extern "C" { -#endif - -#include /* needed for malloc_stats */ -#include /* needed for overflow checks */ -#include /* needed to set errno to ENOMEM */ - -#ifdef WIN32 -#define WIN32_LEAN_AND_MEAN -#include -#endif - -/* - Compile-time options -*/ - - -/* - - Special defines for Cygnus newlib distribution. - - */ - -#ifdef _LIBC - -#include - -/* - In newlib, all the publically visible routines take a reentrancy - pointer. We don't currently do anything much with it, but we do - pass it to the lock routine. - */ - -#include - -#define POINTER_UINT unsigned _POINTER_INT -#define SEPARATE_OBJECTS -#define HAVE_MMAP 0 -#define MORECORE(size) _sbrk_r(reent_ptr, (size)) -#define MORECORE_CLEARS 0 -#define MALLOC_LOCK __malloc_lock(reent_ptr) -#define MALLOC_UNLOCK __malloc_unlock(reent_ptr) - -#ifdef __CYGWIN__ -# undef _WIN32 -# undef WIN32 -#endif - -#ifndef _WIN32 -#ifdef SMALL_MEMORY -#define malloc_getpagesize (128) -#else -#define malloc_getpagesize (4096) -#endif -#endif - -#if __STD_C -extern void __malloc_lock(struct _reent *); -extern void __malloc_unlock(struct _reent *); -#else -extern void __malloc_lock(); -extern void __malloc_unlock(); -#endif - -#if __STD_C -#define RARG struct _reent *reent_ptr, -#define RONEARG struct _reent *reent_ptr -#else -#define RARG reent_ptr -#define RONEARG reent_ptr -#define RDECL struct _reent *reent_ptr; -#endif - -#define RERRNO reent_ptr->_errno -#define RCALL reent_ptr, -#define RONECALL reent_ptr - -#else /* ! _LIBC */ - -#define POINTER_UINT unsigned long -#define RARG -#define RONEARG -#define RDECL -#define RERRNO errno -#define RCALL -#define RONECALL - -#endif /* ! _LIBC */ - -/* - Debugging: - - Because freed chunks may be overwritten with link fields, this - malloc will often die when freed memory is overwritten by user - programs. This can be very effective (albeit in an annoying way) - in helping track down dangling pointers. - - If you compile with -DDEBUG, a number of assertion checks are - enabled that will catch more memory errors. You probably won't be - able to make much sense of the actual assertion errors, but they - should help you locate incorrectly overwritten memory. The - checking is fairly extensive, and will slow down execution - noticeably. Calling malloc_stats or mallinfo with DEBUG set will - attempt to check every non-mmapped allocated and free chunk in the - course of computing the summmaries. (By nature, mmapped regions - cannot be checked very much automatically.) - - Setting DEBUG may also be helpful if you are trying to modify - this code. The assertions in the check routines spell out in more - detail the assumptions and invariants underlying the algorithms. - -*/ - -#if DEBUG -#include -#else -#define assert(x) ((void)0) -#endif - - -/* - SEPARATE_OBJECTS should be defined if you want each function to go - into a separate .o file. You must then compile malloc.c once per - function, defining the appropriate DEFINE_ macro. See below for the - list of macros. - */ - -#ifndef SEPARATE_OBJECTS -#define DEFINE_MALLOC -#define DEFINE_FREE -#define DEFINE_REALLOC -#define DEFINE_CALLOC -#define DEFINE_CFREE -#define DEFINE_MEMALIGN -#define DEFINE_VALLOC -#define DEFINE_PVALLOC -#define DEFINE_MALLINFO -#define DEFINE_MALLOC_STATS -#define DEFINE_MALLOC_USABLE_SIZE -#define DEFINE_MALLOPT - -#define STATIC static -#else -#define STATIC -#endif - -/* - Define MALLOC_LOCK and MALLOC_UNLOCK to C expressions to run to - lock and unlock the malloc data structures. MALLOC_LOCK may be - called recursively. - */ - -#ifndef MALLOC_LOCK -#define MALLOC_LOCK -#endif - -#ifndef MALLOC_UNLOCK -#define MALLOC_UNLOCK -#endif - -/* - INTERNAL_SIZE_T is the word-size used for internal bookkeeping - of chunk sizes. On a 64-bit machine, you can reduce malloc - overhead by defining INTERNAL_SIZE_T to be a 32 bit `unsigned int' - at the expense of not being able to handle requests greater than - 2^31. This limitation is hardly ever a concern; you are encouraged - to set this. However, the default version is the same as size_t. -*/ - -#ifndef INTERNAL_SIZE_T -#define INTERNAL_SIZE_T size_t -#endif - -/* - Following is needed on implementations whereby long > size_t. - The problem is caused because the code performs subtractions of - size_t values and stores the result in long values. In the case - where long > size_t and the first value is actually less than - the second value, the resultant value is positive. For example, - (long)(x - y) where x = 0 and y is 1 ends up being 0x00000000FFFFFFFF - which is 2*31 - 1 instead of 0xFFFFFFFFFFFFFFFF. This is due to the - fact that assignment from unsigned to signed won't sign extend. -*/ - -#define long_sub_size_t(x, y) \ - (sizeof (long) > sizeof (INTERNAL_SIZE_T) && x < y \ - ? -(long) (y - x) \ - : (long) (x - y)) - -/* - REALLOC_ZERO_BYTES_FREES should be set if a call to - realloc with zero bytes should be the same as a call to free. - Some people think it should. Otherwise, since this malloc - returns a unique pointer for malloc(0), so does realloc(p, 0). -*/ - - -/* #define REALLOC_ZERO_BYTES_FREES */ - - -/* - WIN32 causes an emulation of sbrk to be compiled in - mmap-based options are not currently supported in WIN32. -*/ - -/* #define WIN32 */ -#ifdef WIN32 -#define MORECORE wsbrk -#define HAVE_MMAP 0 -#endif - - -/* - HAVE_MEMCPY should be defined if you are not otherwise using - ANSI STD C, but still have memcpy and memset in your C library - and want to use them in calloc and realloc. Otherwise simple - macro versions are defined here. - - USE_MEMCPY should be defined as 1 if you actually want to - have memset and memcpy called. People report that the macro - versions are often enough faster than libc versions on many - systems that it is better to use them. - -*/ - -#define HAVE_MEMCPY - -/* Although the original macro is called USE_MEMCPY, newlib actually - uses memmove to handle cases whereby a platform's memcpy implementation - copies backwards and thus destructive overlap may occur in realloc - whereby we are reclaiming free memory prior to the old allocation. */ -#ifndef USE_MEMCPY -#ifdef HAVE_MEMCPY -#define USE_MEMCPY 1 -#else -#define USE_MEMCPY 0 -#endif -#endif - -#if (__STD_C || defined(HAVE_MEMCPY)) - -#if __STD_C -void* memset(void*, int, size_t); -void* memcpy(void*, const void*, size_t); -void* memmove(void*, const void*, size_t); -#else -Void_t* memset(); -Void_t* memcpy(); -Void_t* memmove(); -#endif -#endif - -#if USE_MEMCPY - -/* The following macros are only invoked with (2n+1)-multiples of - INTERNAL_SIZE_T units, with a positive integer n. This is exploited - for fast inline execution when n is small. */ - -#define MALLOC_ZERO(charp, nbytes) \ -do { \ - INTERNAL_SIZE_T mzsz = (nbytes); \ - if(mzsz <= 9*sizeof(mzsz)) { \ - INTERNAL_SIZE_T* mz = (INTERNAL_SIZE_T*) (charp); \ - if(mzsz >= 5*sizeof(mzsz)) { *mz++ = 0; \ - *mz++ = 0; \ - if(mzsz >= 7*sizeof(mzsz)) { *mz++ = 0; \ - *mz++ = 0; \ - if(mzsz >= 9*sizeof(mzsz)) { *mz++ = 0; \ - *mz++ = 0; }}} \ - *mz++ = 0; \ - *mz++ = 0; \ - *mz = 0; \ - } else memset((charp), 0, mzsz); \ -} while(0) - -#define MALLOC_COPY(dest,src,nbytes) \ -do { \ - INTERNAL_SIZE_T mcsz = (nbytes); \ - if(mcsz <= 9*sizeof(mcsz)) { \ - INTERNAL_SIZE_T* mcsrc = (INTERNAL_SIZE_T*) (src); \ - INTERNAL_SIZE_T* mcdst = (INTERNAL_SIZE_T*) (dest); \ - if(mcsz >= 5*sizeof(mcsz)) { *mcdst++ = *mcsrc++; \ - *mcdst++ = *mcsrc++; \ - if(mcsz >= 7*sizeof(mcsz)) { *mcdst++ = *mcsrc++; \ - *mcdst++ = *mcsrc++; \ - if(mcsz >= 9*sizeof(mcsz)) { *mcdst++ = *mcsrc++; \ - *mcdst++ = *mcsrc++; }}} \ - *mcdst++ = *mcsrc++; \ - *mcdst++ = *mcsrc++; \ - *mcdst = *mcsrc ; \ - } else memmove(dest, src, mcsz); \ -} while(0) - -#else /* !USE_MEMCPY */ - -/* Use Duff's device for good zeroing/copying performance. */ - -#define MALLOC_ZERO(charp, nbytes) \ -do { \ - INTERNAL_SIZE_T* mzp = (INTERNAL_SIZE_T*)(charp); \ - long mctmp = (nbytes)/sizeof(INTERNAL_SIZE_T), mcn; \ - if (mctmp < 8) mcn = 0; else { mcn = (mctmp-1)/8; mctmp %= 8; } \ - switch (mctmp) { \ - case 0: for(;;) { *mzp++ = 0; \ - case 7: *mzp++ = 0; \ - case 6: *mzp++ = 0; \ - case 5: *mzp++ = 0; \ - case 4: *mzp++ = 0; \ - case 3: *mzp++ = 0; \ - case 2: *mzp++ = 0; \ - case 1: *mzp++ = 0; if(mcn <= 0) break; mcn--; } \ - } \ -} while(0) - -#define MALLOC_COPY(dest,src,nbytes) \ -do { \ - INTERNAL_SIZE_T* mcsrc = (INTERNAL_SIZE_T*) src; \ - INTERNAL_SIZE_T* mcdst = (INTERNAL_SIZE_T*) dest; \ - long mctmp = (nbytes)/sizeof(INTERNAL_SIZE_T), mcn; \ - if (mctmp < 8) mcn = 0; else { mcn = (mctmp-1)/8; mctmp %= 8; } \ - switch (mctmp) { \ - case 0: for(;;) { *mcdst++ = *mcsrc++; \ - case 7: *mcdst++ = *mcsrc++; \ - case 6: *mcdst++ = *mcsrc++; \ - case 5: *mcdst++ = *mcsrc++; \ - case 4: *mcdst++ = *mcsrc++; \ - case 3: *mcdst++ = *mcsrc++; \ - case 2: *mcdst++ = *mcsrc++; \ - case 1: *mcdst++ = *mcsrc++; if(mcn <= 0) break; mcn--; } \ - } \ -} while(0) - -#endif - - -/* - Define HAVE_MMAP to optionally make malloc() use mmap() to - allocate very large blocks. These will be returned to the - operating system immediately after a free(). -*/ - -#ifndef HAVE_MMAP -#define HAVE_MMAP 1 -#endif - -/* - Define HAVE_MREMAP to make realloc() use mremap() to re-allocate - large blocks. This is currently only possible on Linux with - kernel versions newer than 1.3.77. -*/ - -#ifndef HAVE_MREMAP -#ifdef INTERNAL_LINUX_C_LIB -#define HAVE_MREMAP 1 -#else -#define HAVE_MREMAP 0 -#endif -#endif - -#if HAVE_MMAP - -#include -#include -#include - -#if !defined(MAP_ANONYMOUS) && defined(MAP_ANON) -#define MAP_ANONYMOUS MAP_ANON -#endif - -#endif /* HAVE_MMAP */ - -/* - Access to system page size. To the extent possible, this malloc - manages memory from the system in page-size units. - - The following mechanics for getpagesize were adapted from - bsd/gnu getpagesize.h -*/ - -#ifndef LACKS_UNISTD_H -# include -#endif - -#ifndef malloc_getpagesize -# ifdef _SC_PAGESIZE /* some SVR4 systems omit an underscore */ -# ifndef _SC_PAGE_SIZE -# define _SC_PAGE_SIZE _SC_PAGESIZE -# endif -# endif -# ifdef _SC_PAGE_SIZE -# define malloc_getpagesize sysconf(_SC_PAGE_SIZE) -# else -# if defined(BSD) || defined(DGUX) || defined(HAVE_GETPAGESIZE) - extern size_t getpagesize(); -# define malloc_getpagesize getpagesize() -# else -# include -# ifdef EXEC_PAGESIZE -# define malloc_getpagesize EXEC_PAGESIZE -# else -# ifdef NBPG -# ifndef CLSIZE -# define malloc_getpagesize NBPG -# else -# define malloc_getpagesize (NBPG * CLSIZE) -# endif -# else -# ifdef NBPC -# define malloc_getpagesize NBPC -# else -# ifdef PAGESIZE -# define malloc_getpagesize PAGESIZE -# else -# define malloc_getpagesize (4096) /* just guess */ -# endif -# endif -# endif -# endif -# endif -# endif -#endif - - - -/* - - This version of malloc supports the standard SVID/XPG mallinfo - routine that returns a struct containing the same kind of - information you can get from malloc_stats. It should work on - any SVID/XPG compliant system that has a /usr/include/malloc.h - defining struct mallinfo. (If you'd like to install such a thing - yourself, cut out the preliminary declarations as described above - and below and save them in a malloc.h file. But there's no - compelling reason to bother to do this.) - - The main declaration needed is the mallinfo struct that is returned - (by-copy) by mallinfo(). The SVID/XPG malloinfo struct contains a - bunch of fields, most of which are not even meaningful in this - version of malloc. Some of these fields are are instead filled by - mallinfo() with other numbers that might possibly be of interest. - - HAVE_USR_INCLUDE_MALLOC_H should be set if you have a - /usr/include/malloc.h file that includes a declaration of struct - mallinfo. If so, it is included; else an SVID2/XPG2 compliant - version is declared below. These must be precisely the same for - mallinfo() to work. - -*/ - -/* #define HAVE_USR_INCLUDE_MALLOC_H */ - -#if HAVE_USR_INCLUDE_MALLOC_H -#include "/usr/include/malloc.h" -#else - -/* SVID2/XPG mallinfo structure */ - -struct mallinfo { - int arena; /* total space allocated from system */ - int ordblks; /* number of non-inuse chunks */ - int smblks; /* unused -- always zero */ - int hblks; /* number of mmapped regions */ - int hblkhd; /* total space in mmapped regions */ - int usmblks; /* unused -- always zero */ - int fsmblks; /* unused -- always zero */ - int uordblks; /* total allocated space */ - int fordblks; /* total non-inuse space */ - int keepcost; /* top-most, releasable (via malloc_trim) space */ -}; - -/* SVID2/XPG mallopt options */ - -#define M_MXFAST 1 /* UNUSED in this malloc */ -#define M_NLBLKS 2 /* UNUSED in this malloc */ -#define M_GRAIN 3 /* UNUSED in this malloc */ -#define M_KEEP 4 /* UNUSED in this malloc */ - -#endif - -/* mallopt options that actually do something */ - -#define M_TRIM_THRESHOLD -1 -#define M_TOP_PAD -2 -#define M_MMAP_THRESHOLD -3 -#define M_MMAP_MAX -4 - - - -#ifndef DEFAULT_TRIM_THRESHOLD -#define DEFAULT_TRIM_THRESHOLD (128L * 1024L) -#endif - -/* - M_TRIM_THRESHOLD is the maximum amount of unused top-most memory - to keep before releasing via malloc_trim in free(). - - Automatic trimming is mainly useful in long-lived programs. - Because trimming via sbrk can be slow on some systems, and can - sometimes be wasteful (in cases where programs immediately - afterward allocate more large chunks) the value should be high - enough so that your overall system performance would improve by - releasing. - - The trim threshold and the mmap control parameters (see below) - can be traded off with one another. Trimming and mmapping are - two different ways of releasing unused memory back to the - system. Between these two, it is often possible to keep - system-level demands of a long-lived program down to a bare - minimum. For example, in one test suite of sessions measuring - the XF86 X server on Linux, using a trim threshold of 128K and a - mmap threshold of 192K led to near-minimal long term resource - consumption. - - If you are using this malloc in a long-lived program, it should - pay to experiment with these values. As a rough guide, you - might set to a value close to the average size of a process - (program) running on your system. Releasing this much memory - would allow such a process to run in memory. Generally, it's - worth it to tune for trimming rather tham memory mapping when a - program undergoes phases where several large chunks are - allocated and released in ways that can reuse each other's - storage, perhaps mixed with phases where there are no such - chunks at all. And in well-behaved long-lived programs, - controlling release of large blocks via trimming versus mapping - is usually faster. - - However, in most programs, these parameters serve mainly as - protection against the system-level effects of carrying around - massive amounts of unneeded memory. Since frequent calls to - sbrk, mmap, and munmap otherwise degrade performance, the default - parameters are set to relatively high values that serve only as - safeguards. - - The default trim value is high enough to cause trimming only in - fairly extreme (by current memory consumption standards) cases. - It must be greater than page size to have any useful effect. To - disable trimming completely, you can set to (unsigned long)(-1); - - -*/ - - -#ifndef DEFAULT_TOP_PAD -#define DEFAULT_TOP_PAD (0) -#endif - -/* - M_TOP_PAD is the amount of extra `padding' space to allocate or - retain whenever sbrk is called. It is used in two ways internally: - - * When sbrk is called to extend the top of the arena to satisfy - a new malloc request, this much padding is added to the sbrk - request. - - * When malloc_trim is called automatically from free(), - it is used as the `pad' argument. - - In both cases, the actual amount of padding is rounded - so that the end of the arena is always a system page boundary. - - The main reason for using padding is to avoid calling sbrk so - often. Having even a small pad greatly reduces the likelihood - that nearly every malloc request during program start-up (or - after trimming) will invoke sbrk, which needlessly wastes - time. - - Automatic rounding-up to page-size units is normally sufficient - to avoid measurable overhead, so the default is 0. However, in - systems where sbrk is relatively slow, it can pay to increase - this value, at the expense of carrying around more memory than - the program needs. - -*/ - - -#ifndef DEFAULT_MMAP_THRESHOLD -#define DEFAULT_MMAP_THRESHOLD (128 * 1024) -#endif - -/* - - M_MMAP_THRESHOLD is the request size threshold for using mmap() - to service a request. Requests of at least this size that cannot - be allocated using already-existing space will be serviced via mmap. - (If enough normal freed space already exists it is used instead.) - - Using mmap segregates relatively large chunks of memory so that - they can be individually obtained and released from the host - system. A request serviced through mmap is never reused by any - other request (at least not directly; the system may just so - happen to remap successive requests to the same locations). - - Segregating space in this way has the benefit that mmapped space - can ALWAYS be individually released back to the system, which - helps keep the system level memory demands of a long-lived - program low. Mapped memory can never become `locked' between - other chunks, as can happen with normally allocated chunks, which - menas that even trimming via malloc_trim would not release them. - - However, it has the disadvantages that: - - 1. The space cannot be reclaimed, consolidated, and then - used to service later requests, as happens with normal chunks. - 2. It can lead to more wastage because of mmap page alignment - requirements - 3. It causes malloc performance to be more dependent on host - system memory management support routines which may vary in - implementation quality and may impose arbitrary - limitations. Generally, servicing a request via normal - malloc steps is faster than going through a system's mmap. - - All together, these considerations should lead you to use mmap - only for relatively large requests. - - -*/ - - - -#ifndef DEFAULT_MMAP_MAX -#if HAVE_MMAP -#define DEFAULT_MMAP_MAX (64) -#else -#define DEFAULT_MMAP_MAX (0) -#endif -#endif - -/* - M_MMAP_MAX is the maximum number of requests to simultaneously - service using mmap. This parameter exists because: - - 1. Some systems have a limited number of internal tables for - use by mmap. - 2. In most systems, overreliance on mmap can degrade overall - performance. - 3. If a program allocates many large regions, it is probably - better off using normal sbrk-based allocation routines that - can reclaim and reallocate normal heap memory. Using a - small value allows transition into this mode after the - first few allocations. - - Setting to 0 disables all use of mmap. If HAVE_MMAP is not set, - the default value is 0, and attempts to set it to non-zero values - in mallopt will fail. -*/ - - - - -/* - - Special defines for linux libc - - Except when compiled using these special defines for Linux libc - using weak aliases, this malloc is NOT designed to work in - multithreaded applications. No semaphores or other concurrency - control are provided to ensure that multiple malloc or free calls - don't run at the same time, which could be disasterous. A single - semaphore could be used across malloc, realloc, and free (which is - essentially the effect of the linux weak alias approach). It would - be hard to obtain finer granularity. - -*/ - - -#ifdef INTERNAL_LINUX_C_LIB - -#if __STD_C - -Void_t * __default_morecore_init (ptrdiff_t); -Void_t *(*__morecore)(ptrdiff_t) = __default_morecore_init; - -#else - -Void_t * __default_morecore_init (); -Void_t *(*__morecore)() = __default_morecore_init; - -#endif - -#define MORECORE (*__morecore) -#define MORECORE_FAILURE 0 -#define MORECORE_CLEARS 1 - -#else /* INTERNAL_LINUX_C_LIB */ - -#ifndef _LIBC -#if __STD_C -extern Void_t* sbrk(ptrdiff_t); -#else -extern Void_t* sbrk(); -#endif -#endif - -#ifndef MORECORE -#define MORECORE sbrk -#endif - -#ifndef MORECORE_FAILURE -#define MORECORE_FAILURE -1 -#endif - -#ifndef MORECORE_CLEARS -#define MORECORE_CLEARS 1 -#endif - -#endif /* INTERNAL_LINUX_C_LIB */ - -#if defined(INTERNAL_LINUX_C_LIB) && defined(__ELF__) - -#define cALLOc __libc_calloc -#define fREe __libc_free -#define mALLOc __libc_malloc -#define mEMALIGn __libc_memalign -#define rEALLOc __libc_realloc -#define vALLOc __libc_valloc -#define pvALLOc __libc_pvalloc -#define mALLINFo __libc_mallinfo -#define mALLOPt __libc_mallopt - -#pragma weak calloc = __libc_calloc -#pragma weak free = __libc_free -#pragma weak cfree = __libc_free -#pragma weak malloc = __libc_malloc -#pragma weak memalign = __libc_memalign -#pragma weak realloc = __libc_realloc -#pragma weak valloc = __libc_valloc -#pragma weak pvalloc = __libc_pvalloc -#pragma weak mallinfo = __libc_mallinfo -#pragma weak mallopt = __libc_mallopt - -#else - -#ifdef _LIBC - -#define cALLOc _calloc_r -#define fREe _free_r -#define mALLOc _malloc_r -#define mEMALIGn _memalign_r -#define rEALLOc _realloc_r -#define vALLOc _valloc_r -#define pvALLOc _pvalloc_r -#define mALLINFo _mallinfo_r -#define mALLOPt _mallopt_r - -#define malloc_stats _malloc_stats_r -#define malloc_trim _malloc_trim_r -#define malloc_usable_size _malloc_usable_size_r - -#define malloc_update_mallinfo __malloc_update_mallinfo - -#define malloc_av_ __malloc_av_ -#define malloc_current_mallinfo __malloc_current_mallinfo -#define malloc_max_sbrked_mem __malloc_max_sbrked_mem -#define malloc_max_total_mem __malloc_max_total_mem -#define malloc_sbrk_base __malloc_sbrk_base -#define malloc_top_pad __malloc_top_pad -#define malloc_trim_threshold __malloc_trim_threshold - -#else /* ! _LIBC */ - -#define cALLOc calloc -#define fREe free -#define mALLOc malloc -#define mEMALIGn memalign -#define rEALLOc realloc -#define vALLOc valloc -#define pvALLOc pvalloc -#define mALLINFo mallinfo -#define mALLOPt mallopt - -#endif /* ! _LIBC */ -#endif - -/* Public routines */ - -#if __STD_C - -Void_t* mALLOc(RARG size_t); -void fREe(RARG Void_t*); -Void_t* rEALLOc(RARG Void_t*, size_t); -Void_t* mEMALIGn(RARG size_t, size_t); -Void_t* vALLOc(RARG size_t); -Void_t* pvALLOc(RARG size_t); -Void_t* cALLOc(RARG size_t, size_t); -void cfree(Void_t*); -int malloc_trim(RARG size_t); -size_t malloc_usable_size(RARG Void_t*); -void malloc_stats(RONEARG); -int mALLOPt(RARG int, int); -struct mallinfo mALLINFo(RONEARG); -#else -Void_t* mALLOc(); -void fREe(); -Void_t* rEALLOc(); -Void_t* mEMALIGn(); -Void_t* vALLOc(); -Void_t* pvALLOc(); -Void_t* cALLOc(); -void cfree(); -int malloc_trim(); -size_t malloc_usable_size(); -void malloc_stats(); -int mALLOPt(); -struct mallinfo mALLINFo(); -#endif - - -#ifdef __cplusplus -}; /* end of extern "C" */ -#endif - -/* ---------- To make a malloc.h, end cutting here ------------ */ - - -/* - Emulation of sbrk for WIN32 - All code within the ifdef WIN32 is untested by me. -*/ - - -#ifdef WIN32 - -#define AlignPage(add) (((add) + (malloc_getpagesize-1)) & \ -~(malloc_getpagesize-1)) - -/* resrve 64MB to insure large contiguous space */ -#define RESERVED_SIZE (1024*1024*64) -#define NEXT_SIZE (2048*1024) -#define TOP_MEMORY ((unsigned long)2*1024*1024*1024) - -struct GmListElement; -typedef struct GmListElement GmListElement; - -struct GmListElement -{ - GmListElement* next; - void* base; -}; - -static GmListElement* head = 0; -static unsigned int gNextAddress = 0; -static unsigned int gAddressBase = 0; -static unsigned int gAllocatedSize = 0; - -static -GmListElement* makeGmListElement (void* bas) -{ - GmListElement* this; - this = (GmListElement*)(void*)LocalAlloc (0, sizeof (GmListElement)); - ASSERT (this); - if (this) - { - this->base = bas; - this->next = head; - head = this; - } - return this; -} - -void gcleanup () -{ - BOOL rval; - ASSERT ( (head == NULL) || (head->base == (void*)gAddressBase)); - if (gAddressBase && (gNextAddress - gAddressBase)) - { - rval = VirtualFree ((void*)gAddressBase, - gNextAddress - gAddressBase, - MEM_DECOMMIT); - ASSERT (rval); - } - while (head) - { - GmListElement* next = head->next; - rval = VirtualFree (head->base, 0, MEM_RELEASE); - ASSERT (rval); - LocalFree (head); - head = next; - } -} - -static -void* findRegion (void* start_address, unsigned long size) -{ - MEMORY_BASIC_INFORMATION info; - while ((unsigned long)start_address < TOP_MEMORY) - { - VirtualQuery (start_address, &info, sizeof (info)); - if (info.State != MEM_FREE) - start_address = (char*)info.BaseAddress + info.RegionSize; - else if (info.RegionSize >= size) - return start_address; - else - start_address = (char*)info.BaseAddress + info.RegionSize; - } - return NULL; - -} - - -void* wsbrk (long size) -{ - void* tmp; - if (size > 0) - { - if (gAddressBase == 0) - { - gAllocatedSize = max (RESERVED_SIZE, AlignPage (size)); - gNextAddress = gAddressBase = - (unsigned int)VirtualAlloc (NULL, gAllocatedSize, - MEM_RESERVE, PAGE_NOACCESS); - } else if (AlignPage (gNextAddress + size) > (gAddressBase + -gAllocatedSize)) - { - long new_size = max (NEXT_SIZE, AlignPage (size)); - void* new_address = (void*)(gAddressBase+gAllocatedSize); - do - { - new_address = findRegion (new_address, new_size); - - if (new_address == 0) - return (void*)-1; - - gAddressBase = gNextAddress = - (unsigned int)VirtualAlloc (new_address, new_size, - MEM_RESERVE, PAGE_NOACCESS); - // repeat in case of race condition - // The region that we found has been snagged - // by another thread - } - while (gAddressBase == 0); - - ASSERT (new_address == (void*)gAddressBase); - - gAllocatedSize = new_size; - - if (!makeGmListElement ((void*)gAddressBase)) - return (void*)-1; - } - if ((size + gNextAddress) > AlignPage (gNextAddress)) - { - void* res; - res = VirtualAlloc ((void*)AlignPage (gNextAddress), - (size + gNextAddress - - AlignPage (gNextAddress)), - MEM_COMMIT, PAGE_READWRITE); - if (res == 0) - return (void*)-1; - } - tmp = (void*)gNextAddress; - gNextAddress = (unsigned int)tmp + size; - return tmp; - } - else if (size < 0) - { - unsigned int alignedGoal = AlignPage (gNextAddress + size); - /* Trim by releasing the virtual memory */ - if (alignedGoal >= gAddressBase) - { - VirtualFree ((void*)alignedGoal, gNextAddress - alignedGoal, - MEM_DECOMMIT); - gNextAddress = gNextAddress + size; - return (void*)gNextAddress; - } - else - { - VirtualFree ((void*)gAddressBase, gNextAddress - gAddressBase, - MEM_DECOMMIT); - gNextAddress = gAddressBase; - return (void*)-1; - } - } - else - { - return (void*)gNextAddress; - } -} - -#endif - - - -/* - Type declarations -*/ - - -struct malloc_chunk -{ - INTERNAL_SIZE_T prev_size; /* Size of previous chunk (if free). */ - INTERNAL_SIZE_T size; /* Size in bytes, including overhead. */ - struct malloc_chunk* fd; /* double links -- used only if free. */ - struct malloc_chunk* bk; -}; - -typedef struct malloc_chunk* mchunkptr; - -/* - - malloc_chunk details: - - (The following includes lightly edited explanations by Colin Plumb.) - - Chunks of memory are maintained using a `boundary tag' method as - described in e.g., Knuth or Standish. (See the paper by Paul - Wilson ftp://ftp.cs.utexas.edu/pub/garbage/allocsrv.ps for a - survey of such techniques.) Sizes of free chunks are stored both - in the front of each chunk and at the end. This makes - consolidating fragmented chunks into bigger chunks very fast. The - size fields also hold bits representing whether chunks are free or - in use. - - An allocated chunk looks like this: - - - chunk-> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ - | Size of previous chunk, if allocated | | - +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ - | Size of chunk, in bytes |P| - mem-> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ - | User data starts here... . - . . - . (malloc_usable_space() bytes) . - . | -nextchunk-> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ - | Size of chunk | - +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ - - - Where "chunk" is the front of the chunk for the purpose of most of - the malloc code, but "mem" is the pointer that is returned to the - user. "Nextchunk" is the beginning of the next contiguous chunk. - - Chunks always begin on even word boundries, so the mem portion - (which is returned to the user) is also on an even word boundary, and - thus double-word aligned. - - Free chunks are stored in circular doubly-linked lists, and look like this: - - chunk-> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ - | Size of previous chunk | - +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ - `head:' | Size of chunk, in bytes |P| - mem-> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ - | Forward pointer to next chunk in list | - +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ - | Back pointer to previous chunk in list | - +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ - | Unused space (may be 0 bytes long) . - . . - . | -nextchunk-> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ - `foot:' | Size of chunk, in bytes | - +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ - - The P (PREV_INUSE) bit, stored in the unused low-order bit of the - chunk size (which is always a multiple of two words), is an in-use - bit for the *previous* chunk. If that bit is *clear*, then the - word before the current chunk size contains the previous chunk - size, and can be used to find the front of the previous chunk. - (The very first chunk allocated always has this bit set, - preventing access to non-existent (or non-owned) memory.) - - Note that the `foot' of the current chunk is actually represented - as the prev_size of the NEXT chunk. (This makes it easier to - deal with alignments etc). - - The two exceptions to all this are - - 1. The special chunk `top', which doesn't bother using the - trailing size field since there is no - next contiguous chunk that would have to index off it. (After - initialization, `top' is forced to always exist. If it would - become less than MINSIZE bytes long, it is replenished via - malloc_extend_top.) - - 2. Chunks allocated via mmap, which have the second-lowest-order - bit (IS_MMAPPED) set in their size fields. Because they are - never merged or traversed from any other chunk, they have no - foot size or inuse information. - - Available chunks are kept in any of several places (all declared below): - - * `av': An array of chunks serving as bin headers for consolidated - chunks. Each bin is doubly linked. The bins are approximately - proportionally (log) spaced. There are a lot of these bins - (128). This may look excessive, but works very well in - practice. All procedures maintain the invariant that no - consolidated chunk physically borders another one. Chunks in - bins are kept in size order, with ties going to the - approximately least recently used chunk. - - The chunks in each bin are maintained in decreasing sorted order by - size. This is irrelevant for the small bins, which all contain - the same-sized chunks, but facilitates best-fit allocation for - larger chunks. (These lists are just sequential. Keeping them in - order almost never requires enough traversal to warrant using - fancier ordered data structures.) Chunks of the same size are - linked with the most recently freed at the front, and allocations - are taken from the back. This results in LRU or FIFO allocation - order, which tends to give each chunk an equal opportunity to be - consolidated with adjacent freed chunks, resulting in larger free - chunks and less fragmentation. - - * `top': The top-most available chunk (i.e., the one bordering the - end of available memory) is treated specially. It is never - included in any bin, is used only if no other chunk is - available, and is released back to the system if it is very - large (see M_TRIM_THRESHOLD). - - * `last_remainder': A bin holding only the remainder of the - most recently split (non-top) chunk. This bin is checked - before other non-fitting chunks, so as to provide better - locality for runs of sequentially allocated chunks. - - * Implicitly, through the host system's memory mapping tables. - If supported, requests greater than a threshold are usually - serviced via calls to mmap, and then later released via munmap. - -*/ - - - - - - -/* sizes, alignments */ - -#define SIZE_SZ (sizeof(INTERNAL_SIZE_T)) -#ifndef MALLOC_ALIGNMENT -#define MALLOC_ALIGN 8 -#define MALLOC_ALIGNMENT (SIZE_SZ < 4 ? 8 : (SIZE_SZ + SIZE_SZ)) -#else -#define MALLOC_ALIGN MALLOC_ALIGNMENT -#endif -#define MALLOC_ALIGN_MASK (MALLOC_ALIGNMENT - 1) -#define MINSIZE (sizeof(struct malloc_chunk)) - -/* conversion from malloc headers to user pointers, and back */ - -#define chunk2mem(p) ((Void_t*)((char*)(p) + 2*SIZE_SZ)) -#define mem2chunk(mem) ((mchunkptr)((char*)(mem) - 2*SIZE_SZ)) - -/* pad request bytes into a usable size */ - -#define request2size(req) \ - (((unsigned long)((req) + (SIZE_SZ + MALLOC_ALIGN_MASK)) < \ - (unsigned long)(MINSIZE + MALLOC_ALIGN_MASK)) ? ((MINSIZE + MALLOC_ALIGN_MASK) & ~(MALLOC_ALIGN_MASK)) : \ - (((req) + (SIZE_SZ + MALLOC_ALIGN_MASK)) & ~(MALLOC_ALIGN_MASK))) - -/* Check if m has acceptable alignment */ - -#define aligned_OK(m) (((unsigned long)((m)) & (MALLOC_ALIGN_MASK)) == 0) - - - - -/* - Physical chunk operations -*/ - - -/* size field is or'ed with PREV_INUSE when previous adjacent chunk in use */ - -#define PREV_INUSE 0x1 - -/* size field is or'ed with IS_MMAPPED if the chunk was obtained with mmap() */ - -#define IS_MMAPPED 0x2 - -/* Bits to mask off when extracting size */ - -#define SIZE_BITS (PREV_INUSE|IS_MMAPPED) - - -/* Ptr to next physical malloc_chunk. */ - -#define next_chunk(p) ((mchunkptr)( ((char*)(p)) + ((p)->size & ~PREV_INUSE) )) - -/* Ptr to previous physical malloc_chunk */ - -#define prev_chunk(p)\ - ((mchunkptr)( ((char*)(p)) - ((p)->prev_size) )) - - -/* Treat space at ptr + offset as a chunk */ - -#define chunk_at_offset(p, s) ((mchunkptr)(((char*)(p)) + (s))) - - - - -/* - Dealing with use bits -*/ - -/* extract p's inuse bit */ - -#define inuse(p)\ -((((mchunkptr)(((char*)(p))+((p)->size & ~PREV_INUSE)))->size) & PREV_INUSE) - -/* extract inuse bit of previous chunk */ - -#define prev_inuse(p) ((p)->size & PREV_INUSE) - -/* check for mmap()'ed chunk */ - -#define chunk_is_mmapped(p) ((p)->size & IS_MMAPPED) - -/* set/clear chunk as in use without otherwise disturbing */ - -#define set_inuse(p)\ -((mchunkptr)(((char*)(p)) + ((p)->size & ~PREV_INUSE)))->size |= PREV_INUSE - -#define clear_inuse(p)\ -((mchunkptr)(((char*)(p)) + ((p)->size & ~PREV_INUSE)))->size &= ~(PREV_INUSE) - -/* check/set/clear inuse bits in known places */ - -#define inuse_bit_at_offset(p, s)\ - (((mchunkptr)(((char*)(p)) + (s)))->size & PREV_INUSE) - -#define set_inuse_bit_at_offset(p, s)\ - (((mchunkptr)(((char*)(p)) + (s)))->size |= PREV_INUSE) - -#define clear_inuse_bit_at_offset(p, s)\ - (((mchunkptr)(((char*)(p)) + (s)))->size &= ~(PREV_INUSE)) - - - - -/* - Dealing with size fields -*/ - -/* Get size, ignoring use bits */ - -#define chunksize(p) ((p)->size & ~(SIZE_BITS)) - -/* Set size at head, without disturbing its use bit */ - -#define set_head_size(p, s) ((p)->size = (((p)->size & PREV_INUSE) | (s))) - -/* Set size/use ignoring previous bits in header */ - -#define set_head(p, s) ((p)->size = (s)) - -/* Set size at footer (only when chunk is not in use) */ - -#define set_foot(p, s) (((mchunkptr)((char*)(p) + (s)))->prev_size = (s)) - - - - - -/* - Bins - - The bins, `av_' are an array of pairs of pointers serving as the - heads of (initially empty) doubly-linked lists of chunks, laid out - in a way so that each pair can be treated as if it were in a - malloc_chunk. (This way, the fd/bk offsets for linking bin heads - and chunks are the same). - - Bins for sizes < 512 bytes contain chunks of all the same size, spaced - 8 bytes apart. Larger bins are approximately logarithmically - spaced. (See the table below.) The `av_' array is never mentioned - directly in the code, but instead via bin access macros. - - Bin layout: - - 64 bins of size 8 - 32 bins of size 64 - 16 bins of size 512 - 8 bins of size 4096 - 4 bins of size 32768 - 2 bins of size 262144 - 1 bin of size what's left - - There is actually a little bit of slop in the numbers in bin_index - for the sake of speed. This makes no difference elsewhere. - - The special chunks `top' and `last_remainder' get their own bins, - (this is implemented via yet more trickery with the av_ array), - although `top' is never properly linked to its bin since it is - always handled specially. - -*/ - -#ifdef SEPARATE_OBJECTS -#define av_ malloc_av_ -#endif - -#define NAV 128 /* number of bins */ - -typedef struct malloc_chunk* mbinptr; - -/* access macros */ - -#define bin_at(i) ((mbinptr)((char*)&(av_[2*(i) + 2]) - 2*SIZE_SZ)) -#define next_bin(b) ((mbinptr)((char*)(b) + 2 * sizeof(mbinptr))) -#define prev_bin(b) ((mbinptr)((char*)(b) - 2 * sizeof(mbinptr))) - -/* - The first 2 bins are never indexed. The corresponding av_ cells are instead - used for bookkeeping. This is not to save space, but to simplify - indexing, maintain locality, and avoid some initialization tests. -*/ - -#define top (bin_at(0)->fd) /* The topmost chunk */ -#define last_remainder (bin_at(1)) /* remainder from last split */ - - -/* - Because top initially points to its own bin with initial - zero size, thus forcing extension on the first malloc request, - we avoid having any special code in malloc to check whether - it even exists yet. But we still need to in malloc_extend_top. -*/ - -#define initial_top ((mchunkptr)(bin_at(0))) - -/* Helper macro to initialize bins */ - -#define IAV(i) bin_at(i), bin_at(i) - -#ifdef DEFINE_MALLOC -STATIC mbinptr av_[NAV * 2 + 2] = { - 0, 0, - IAV(0), IAV(1), IAV(2), IAV(3), IAV(4), IAV(5), IAV(6), IAV(7), - IAV(8), IAV(9), IAV(10), IAV(11), IAV(12), IAV(13), IAV(14), IAV(15), - IAV(16), IAV(17), IAV(18), IAV(19), IAV(20), IAV(21), IAV(22), IAV(23), - IAV(24), IAV(25), IAV(26), IAV(27), IAV(28), IAV(29), IAV(30), IAV(31), - IAV(32), IAV(33), IAV(34), IAV(35), IAV(36), IAV(37), IAV(38), IAV(39), - IAV(40), IAV(41), IAV(42), IAV(43), IAV(44), IAV(45), IAV(46), IAV(47), - IAV(48), IAV(49), IAV(50), IAV(51), IAV(52), IAV(53), IAV(54), IAV(55), - IAV(56), IAV(57), IAV(58), IAV(59), IAV(60), IAV(61), IAV(62), IAV(63), - IAV(64), IAV(65), IAV(66), IAV(67), IAV(68), IAV(69), IAV(70), IAV(71), - IAV(72), IAV(73), IAV(74), IAV(75), IAV(76), IAV(77), IAV(78), IAV(79), - IAV(80), IAV(81), IAV(82), IAV(83), IAV(84), IAV(85), IAV(86), IAV(87), - IAV(88), IAV(89), IAV(90), IAV(91), IAV(92), IAV(93), IAV(94), IAV(95), - IAV(96), IAV(97), IAV(98), IAV(99), IAV(100), IAV(101), IAV(102), IAV(103), - IAV(104), IAV(105), IAV(106), IAV(107), IAV(108), IAV(109), IAV(110), IAV(111), - IAV(112), IAV(113), IAV(114), IAV(115), IAV(116), IAV(117), IAV(118), IAV(119), - IAV(120), IAV(121), IAV(122), IAV(123), IAV(124), IAV(125), IAV(126), IAV(127) -}; -#else -extern mbinptr av_[NAV * 2 + 2]; -#endif - - - -/* field-extraction macros */ - -#define first(b) ((b)->fd) -#define last(b) ((b)->bk) - -/* - Indexing into bins -*/ - -#define bin_index(sz) \ -(((((unsigned long)(sz)) >> 9) == 0) ? (((unsigned long)(sz)) >> 3): \ - ((((unsigned long)(sz)) >> 9) <= 4) ? 56 + (((unsigned long)(sz)) >> 6): \ - ((((unsigned long)(sz)) >> 9) <= 20) ? 91 + (((unsigned long)(sz)) >> 9): \ - ((((unsigned long)(sz)) >> 9) <= 84) ? 110 + (((unsigned long)(sz)) >> 12): \ - ((((unsigned long)(sz)) >> 9) <= 340) ? 119 + (((unsigned long)(sz)) >> 15): \ - ((((unsigned long)(sz)) >> 9) <= 1364) ? 124 + (((unsigned long)(sz)) >> 18): \ - 126) -/* - bins for chunks < 512 are all spaced SMALLBIN_WIDTH bytes apart, and hold - identically sized chunks. This is exploited in malloc. -*/ - -#define MAX_SMALLBIN_SIZE 512 -#define SMALLBIN_WIDTH 8 -#define SMALLBIN_WIDTH_BITS 3 -#define MAX_SMALLBIN (MAX_SMALLBIN_SIZE / SMALLBIN_WIDTH) - 1 - -#define smallbin_index(sz) (((unsigned long)(sz)) >> SMALLBIN_WIDTH_BITS) - -/* - Requests are `small' if both the corresponding and the next bin are small -*/ - -#define is_small_request(nb) (nb < MAX_SMALLBIN_SIZE - SMALLBIN_WIDTH) - - - -/* - To help compensate for the large number of bins, a one-level index - structure is used for bin-by-bin searching. `binblocks' is a - one-word bitvector recording whether groups of BINBLOCKWIDTH bins - have any (possibly) non-empty bins, so they can be skipped over - all at once during during traversals. The bits are NOT always - cleared as soon as all bins in a block are empty, but instead only - when all are noticed to be empty during traversal in malloc. -*/ - -#define BINBLOCKWIDTH 4 /* bins per block */ - -#define binblocks (bin_at(0)->size) /* bitvector of nonempty blocks */ - -/* bin<->block macros */ - -#define idx2binblock(ix) ((unsigned long)1 << (ix / BINBLOCKWIDTH)) -#define mark_binblock(ii) (binblocks |= idx2binblock(ii)) -#define clear_binblock(ii) (binblocks &= ~(idx2binblock(ii))) - - - - - -/* Other static bookkeeping data */ - -#ifdef SEPARATE_OBJECTS -#define trim_threshold malloc_trim_threshold -#define top_pad malloc_top_pad -#define n_mmaps_max malloc_n_mmaps_max -#define mmap_threshold malloc_mmap_threshold -#define sbrk_base malloc_sbrk_base -#define max_sbrked_mem malloc_max_sbrked_mem -#define max_total_mem malloc_max_total_mem -#define current_mallinfo malloc_current_mallinfo -#define n_mmaps malloc_n_mmaps -#define max_n_mmaps malloc_max_n_mmaps -#define mmapped_mem malloc_mmapped_mem -#define max_mmapped_mem malloc_max_mmapped_mem -#endif - -/* variables holding tunable values */ - -#ifdef DEFINE_MALLOC - -STATIC unsigned long trim_threshold = DEFAULT_TRIM_THRESHOLD; -STATIC unsigned long top_pad = DEFAULT_TOP_PAD; -#if HAVE_MMAP -STATIC unsigned int n_mmaps_max = DEFAULT_MMAP_MAX; -STATIC unsigned long mmap_threshold = DEFAULT_MMAP_THRESHOLD; -#endif - -/* The first value returned from sbrk */ -STATIC char* sbrk_base = (char*)(-1); - -/* The maximum memory obtained from system via sbrk */ -STATIC unsigned long max_sbrked_mem = 0; - -/* The maximum via either sbrk or mmap */ -STATIC unsigned long max_total_mem = 0; - -/* internal working copy of mallinfo */ -STATIC struct mallinfo current_mallinfo = { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 }; - -#if HAVE_MMAP - -/* Tracking mmaps */ - -STATIC unsigned int n_mmaps = 0; -STATIC unsigned int max_n_mmaps = 0; -STATIC unsigned long mmapped_mem = 0; -STATIC unsigned long max_mmapped_mem = 0; - -#endif - -#else /* ! DEFINE_MALLOC */ - -extern unsigned long trim_threshold; -extern unsigned long top_pad; -#if HAVE_MMAP -extern unsigned int n_mmaps_max; -extern unsigned long mmap_threshold; -#endif -extern char* sbrk_base; -extern unsigned long max_sbrked_mem; -extern unsigned long max_total_mem; -extern struct mallinfo current_mallinfo; -#if HAVE_MMAP -extern unsigned int n_mmaps; -extern unsigned int max_n_mmaps; -extern unsigned long mmapped_mem; -extern unsigned long max_mmapped_mem; -#endif - -#endif /* ! DEFINE_MALLOC */ - -/* The total memory obtained from system via sbrk */ -#define sbrked_mem (current_mallinfo.arena) - - - -/* - Debugging support -*/ - -#if DEBUG - - -/* - These routines make a number of assertions about the states - of data structures that should be true at all times. If any - are not true, it's very likely that a user program has somehow - trashed memory. (It's also possible that there is a coding error - in malloc. In which case, please report it!) -*/ - -#if __STD_C -static void do_check_chunk(mchunkptr p) -#else -static void do_check_chunk(p) mchunkptr p; -#endif -{ - INTERNAL_SIZE_T sz = p->size & ~PREV_INUSE; - - /* No checkable chunk is mmapped */ - assert(!chunk_is_mmapped(p)); - - /* Check for legal address ... */ - assert((char*)p >= sbrk_base); - if (p != top) - assert((char*)p + sz <= (char*)top); - else - assert((char*)p + sz <= sbrk_base + sbrked_mem); - -} - - -#if __STD_C -static void do_check_free_chunk(mchunkptr p) -#else -static void do_check_free_chunk(p) mchunkptr p; -#endif -{ - INTERNAL_SIZE_T sz = p->size & ~PREV_INUSE; - mchunkptr next = chunk_at_offset(p, sz); - - do_check_chunk(p); - - /* Check whether it claims to be free ... */ - assert(!inuse(p)); - - /* Unless a special marker, must have OK fields */ - if ((long)sz >= (long)MINSIZE) - { - assert((sz & MALLOC_ALIGN_MASK) == 0); - assert(aligned_OK(chunk2mem(p))); - /* ... matching footer field */ - assert(next->prev_size == sz); - /* ... and is fully consolidated */ - assert(prev_inuse(p)); - assert (next == top || inuse(next)); - - /* ... and has minimally sane links */ - assert(p->fd->bk == p); - assert(p->bk->fd == p); - } - else /* markers are always of size SIZE_SZ */ - assert(sz == SIZE_SZ); -} - -#if __STD_C -static void do_check_inuse_chunk(mchunkptr p) -#else -static void do_check_inuse_chunk(p) mchunkptr p; -#endif -{ - mchunkptr next = next_chunk(p); - do_check_chunk(p); - - /* Check whether it claims to be in use ... */ - assert(inuse(p)); - - /* ... and is surrounded by OK chunks. - Since more things can be checked with free chunks than inuse ones, - if an inuse chunk borders them and debug is on, it's worth doing them. - */ - if (!prev_inuse(p)) - { - mchunkptr prv = prev_chunk(p); - assert(next_chunk(prv) == p); - do_check_free_chunk(prv); - } - if (next == top) - { - assert(prev_inuse(next)); - assert(chunksize(next) >= MINSIZE); - } - else if (!inuse(next)) - do_check_free_chunk(next); - -} - -#if __STD_C -static void do_check_malloced_chunk(mchunkptr p, INTERNAL_SIZE_T s) -#else -static void do_check_malloced_chunk(p, s) mchunkptr p; INTERNAL_SIZE_T s; -#endif -{ - INTERNAL_SIZE_T sz = p->size & ~PREV_INUSE; - long room = long_sub_size_t(sz, s); - - do_check_inuse_chunk(p); - - /* Legal size ... */ - assert((long)sz >= (long)MINSIZE); - assert((sz & MALLOC_ALIGN_MASK) == 0); - assert(room >= 0); - assert(room < (long)MINSIZE); - - /* ... and alignment */ - assert(aligned_OK(chunk2mem(p))); - - - /* ... and was allocated at front of an available chunk */ - assert(prev_inuse(p)); - -} - - -#define check_free_chunk(P) do_check_free_chunk(P) -#define check_inuse_chunk(P) do_check_inuse_chunk(P) -#define check_chunk(P) do_check_chunk(P) -#define check_malloced_chunk(P,N) do_check_malloced_chunk(P,N) -#else -#define check_free_chunk(P) -#define check_inuse_chunk(P) -#define check_chunk(P) -#define check_malloced_chunk(P,N) -#endif - - - -/* - Macro-based internal utilities -*/ - - -/* - Linking chunks in bin lists. - Call these only with variables, not arbitrary expressions, as arguments. -*/ - -/* - Place chunk p of size s in its bin, in size order, - putting it ahead of others of same size. -*/ - - -#define frontlink(P, S, IDX, BK, FD) \ -{ \ - if (S < MAX_SMALLBIN_SIZE) \ - { \ - IDX = smallbin_index(S); \ - mark_binblock(IDX); \ - BK = bin_at(IDX); \ - FD = BK->fd; \ - P->bk = BK; \ - P->fd = FD; \ - FD->bk = BK->fd = P; \ - } \ - else \ - { \ - IDX = bin_index(S); \ - BK = bin_at(IDX); \ - FD = BK->fd; \ - if (FD == BK) mark_binblock(IDX); \ - else \ - { \ - while (FD != BK && S < chunksize(FD)) FD = FD->fd; \ - BK = FD->bk; \ - } \ - P->bk = BK; \ - P->fd = FD; \ - FD->bk = BK->fd = P; \ - } \ -} - - -/* take a chunk off a list */ - -#define unlink(P, BK, FD) \ -{ \ - BK = P->bk; \ - FD = P->fd; \ - FD->bk = BK; \ - BK->fd = FD; \ -} \ - -/* Place p as the last remainder */ - -#define link_last_remainder(P) \ -{ \ - last_remainder->fd = last_remainder->bk = P; \ - P->fd = P->bk = last_remainder; \ -} - -/* Clear the last_remainder bin */ - -#define clear_last_remainder \ - (last_remainder->fd = last_remainder->bk = last_remainder) - - - - - - -/* Routines dealing with mmap(). */ - -#if HAVE_MMAP - -#ifdef DEFINE_MALLOC - -#if __STD_C -static mchunkptr mmap_chunk(size_t size) -#else -static mchunkptr mmap_chunk(size) size_t size; -#endif -{ - size_t page_mask = malloc_getpagesize - 1; - mchunkptr p; - -#ifndef MAP_ANONYMOUS - static int fd = -1; -#endif - - if(n_mmaps >= n_mmaps_max) return 0; /* too many regions */ - - /* For mmapped chunks, the overhead is one SIZE_SZ unit larger, because - * there is no following chunk whose prev_size field could be used. - */ - size = (size + SIZE_SZ + page_mask) & ~page_mask; - -#ifdef MAP_ANONYMOUS - p = (mchunkptr)mmap(0, size, PROT_READ|PROT_WRITE, - MAP_PRIVATE|MAP_ANONYMOUS, -1, 0); -#else /* !MAP_ANONYMOUS */ - if (fd < 0) - { - fd = open("/dev/zero", O_RDWR); - if(fd < 0) return 0; - } - p = (mchunkptr)mmap(0, size, PROT_READ|PROT_WRITE, MAP_PRIVATE, fd, 0); -#endif - - if(p == (mchunkptr)-1) return 0; - - n_mmaps++; - if (n_mmaps > max_n_mmaps) max_n_mmaps = n_mmaps; - - /* We demand that eight bytes into a page must be 8-byte aligned. */ - assert(aligned_OK(chunk2mem(p))); - - /* The offset to the start of the mmapped region is stored - * in the prev_size field of the chunk; normally it is zero, - * but that can be changed in memalign(). - */ - p->prev_size = 0; - set_head(p, size|IS_MMAPPED); - - mmapped_mem += size; - if ((unsigned long)mmapped_mem > (unsigned long)max_mmapped_mem) - max_mmapped_mem = mmapped_mem; - if ((unsigned long)(mmapped_mem + sbrked_mem) > (unsigned long)max_total_mem) - max_total_mem = mmapped_mem + sbrked_mem; - return p; -} - -#endif /* DEFINE_MALLOC */ - -#ifdef SEPARATE_OBJECTS -#define munmap_chunk malloc_munmap_chunk -#endif - -#ifdef DEFINE_FREE - -#if __STD_C -STATIC void munmap_chunk(mchunkptr p) -#else -STATIC void munmap_chunk(p) mchunkptr p; -#endif -{ - INTERNAL_SIZE_T size = chunksize(p); - int ret; - - assert (chunk_is_mmapped(p)); - assert(! ((char*)p >= sbrk_base && (char*)p < sbrk_base + sbrked_mem)); - assert((n_mmaps > 0)); - assert(((p->prev_size + size) & (malloc_getpagesize-1)) == 0); - - n_mmaps--; - mmapped_mem -= (size + p->prev_size); - - ret = munmap((char *)p - p->prev_size, size + p->prev_size); - - /* munmap returns non-zero on failure */ - assert(ret == 0); -} - -#else /* ! DEFINE_FREE */ - -#if __STD_C -extern void munmap_chunk(mchunkptr); -#else -extern void munmap_chunk(); -#endif - -#endif /* ! DEFINE_FREE */ - -#if HAVE_MREMAP - -#ifdef DEFINE_REALLOC - -#if __STD_C -static mchunkptr mremap_chunk(mchunkptr p, size_t new_size) -#else -static mchunkptr mremap_chunk(p, new_size) mchunkptr p; size_t new_size; -#endif -{ - size_t page_mask = malloc_getpagesize - 1; - INTERNAL_SIZE_T offset = p->prev_size; - INTERNAL_SIZE_T size = chunksize(p); - char *cp; - - assert (chunk_is_mmapped(p)); - assert(! ((char*)p >= sbrk_base && (char*)p < sbrk_base + sbrked_mem)); - assert((n_mmaps > 0)); - assert(((size + offset) & (malloc_getpagesize-1)) == 0); - - /* Note the extra SIZE_SZ overhead as in mmap_chunk(). */ - new_size = (new_size + offset + SIZE_SZ + page_mask) & ~page_mask; - - cp = (char *)mremap((char *)p - offset, size + offset, new_size, 1); - - if (cp == (char *)-1) return 0; - - p = (mchunkptr)(cp + offset); - - assert(aligned_OK(chunk2mem(p))); - - assert((p->prev_size == offset)); - set_head(p, (new_size - offset)|IS_MMAPPED); - - mmapped_mem -= size + offset; - mmapped_mem += new_size; - if ((unsigned long)mmapped_mem > (unsigned long)max_mmapped_mem) - max_mmapped_mem = mmapped_mem; - if ((unsigned long)(mmapped_mem + sbrked_mem) > (unsigned long)max_total_mem) - max_total_mem = mmapped_mem + sbrked_mem; - return p; -} - -#endif /* DEFINE_REALLOC */ - -#endif /* HAVE_MREMAP */ - -#endif /* HAVE_MMAP */ - - - - -#ifdef DEFINE_MALLOC - -/* - Extend the top-most chunk by obtaining memory from system. - Main interface to sbrk (but see also malloc_trim). -*/ - -#if __STD_C -static void malloc_extend_top(RARG INTERNAL_SIZE_T nb) -#else -static void malloc_extend_top(RARG nb) RDECL INTERNAL_SIZE_T nb; -#endif -{ - char* brk; /* return value from sbrk */ - INTERNAL_SIZE_T front_misalign; /* unusable bytes at front of sbrked space */ - INTERNAL_SIZE_T correction; /* bytes for 2nd sbrk call */ - int correction_failed = 0; /* whether we should relax the assertion */ - char* new_brk; /* return of 2nd sbrk call */ - INTERNAL_SIZE_T top_size; /* new size of top chunk */ - - mchunkptr old_top = top; /* Record state of old top */ - INTERNAL_SIZE_T old_top_size = chunksize(old_top); - char* old_end = (char*)(chunk_at_offset(old_top, old_top_size)); - - /* Pad request with top_pad plus minimal overhead */ - - INTERNAL_SIZE_T sbrk_size = nb + top_pad + MINSIZE; - unsigned long pagesz = malloc_getpagesize; - - /* If not the first time through, round to preserve page boundary */ - /* Otherwise, we need to correct to a page size below anyway. */ - /* (We also correct below if an intervening foreign sbrk call.) */ - - if (sbrk_base != (char*)(-1)) - sbrk_size = (sbrk_size + (pagesz - 1)) & ~(pagesz - 1); - - brk = (char*)(MORECORE (sbrk_size)); - - /* Fail if sbrk failed or if a foreign sbrk call killed our space */ - if (brk == (char*)(MORECORE_FAILURE) || - (brk < old_end && old_top != initial_top)) - return; - - sbrked_mem += sbrk_size; - - if (brk == old_end /* can just add bytes to current top, unless - previous correction failed */ - && ((POINTER_UINT)old_end & (pagesz - 1)) == 0) - { - top_size = sbrk_size + old_top_size; - set_head(top, top_size | PREV_INUSE); - } - else - { - if (sbrk_base == (char*)(-1)) /* First time through. Record base */ - sbrk_base = brk; - else /* Someone else called sbrk(). Count those bytes as sbrked_mem. */ - sbrked_mem += brk - (char*)old_end; - - /* Guarantee alignment of first new chunk made from this space */ - front_misalign = (POINTER_UINT)chunk2mem(brk) & MALLOC_ALIGN_MASK; - if (front_misalign > 0) - { - correction = (MALLOC_ALIGNMENT) - front_misalign; - brk += correction; - } - else - correction = 0; - - /* Guarantee the next brk will be at a page boundary */ - correction += pagesz - ((POINTER_UINT)(brk + sbrk_size) & (pagesz - 1)); - - /* To guarantee page boundary, correction should be less than pagesz */ - correction &= (pagesz - 1); - - /* Allocate correction */ - new_brk = (char*)(MORECORE (correction)); - if (new_brk == (char*)(MORECORE_FAILURE)) - { - correction = 0; - correction_failed = 1; - new_brk = brk + sbrk_size; - if (front_misalign > 0) - new_brk -= (MALLOC_ALIGNMENT) - front_misalign; - } - - sbrked_mem += correction; - - top = (mchunkptr)brk; - top_size = new_brk - brk + correction; - set_head(top, top_size | PREV_INUSE); - - if (old_top != initial_top) - { - - /* There must have been an intervening foreign sbrk call. */ - /* A double fencepost is necessary to prevent consolidation */ - - /* If not enough space to do this, then user did something very wrong */ - if (old_top_size < MINSIZE) - { - set_head(top, PREV_INUSE); /* will force null return from malloc */ - return; - } - - /* Also keep size a multiple of MALLOC_ALIGNMENT */ - old_top_size = (old_top_size - 3*SIZE_SZ) & ~MALLOC_ALIGN_MASK; - set_head_size(old_top, old_top_size); - chunk_at_offset(old_top, old_top_size )->size = - SIZE_SZ|PREV_INUSE; - chunk_at_offset(old_top, old_top_size + SIZE_SZ)->size = - SIZE_SZ|PREV_INUSE; - /* If possible, release the rest. */ - if (old_top_size >= MINSIZE) - fREe(RCALL chunk2mem(old_top)); - } - } - - if ((unsigned long)sbrked_mem > (unsigned long)max_sbrked_mem) - max_sbrked_mem = sbrked_mem; -#if HAVE_MMAP - if ((unsigned long)(mmapped_mem + sbrked_mem) > (unsigned long)max_total_mem) - max_total_mem = mmapped_mem + sbrked_mem; -#else - if ((unsigned long)(sbrked_mem) > (unsigned long)max_total_mem) - max_total_mem = sbrked_mem; -#endif - - /* We always land on a page boundary */ - assert(((unsigned long)((char*)top + top_size) & (pagesz - 1)) == 0 - || correction_failed); -} - -#endif /* DEFINE_MALLOC */ - - -/* Main public routines */ - -#ifdef DEFINE_MALLOC - -/* - Malloc Algorthim: - - The requested size is first converted into a usable form, `nb'. - This currently means to add 4 bytes overhead plus possibly more to - obtain 8-byte alignment and/or to obtain a size of at least - MINSIZE (currently 16 bytes), the smallest allocatable size. - (All fits are considered `exact' if they are within MINSIZE bytes.) - - From there, the first successful of the following steps is taken: - - 1. The bin corresponding to the request size is scanned, and if - a chunk of exactly the right size is found, it is taken. - - 2. The most recently remaindered chunk is used if it is big - enough. This is a form of (roving) first fit, used only in - the absence of exact fits. Runs of consecutive requests use - the remainder of the chunk used for the previous such request - whenever possible. This limited use of a first-fit style - allocation strategy tends to give contiguous chunks - coextensive lifetimes, which improves locality and can reduce - fragmentation in the long run. - - 3. Other bins are scanned in increasing size order, using a - chunk big enough to fulfill the request, and splitting off - any remainder. This search is strictly by best-fit; i.e., - the smallest (with ties going to approximately the least - recently used) chunk that fits is selected. - - 4. If large enough, the chunk bordering the end of memory - (`top') is split off. (This use of `top' is in accord with - the best-fit search rule. In effect, `top' is treated as - larger (and thus less well fitting) than any other available - chunk since it can be extended to be as large as necessary - (up to system limitations). - - 5. If the request size meets the mmap threshold and the - system supports mmap, and there are few enough currently - allocated mmapped regions, and a call to mmap succeeds, - the request is allocated via direct memory mapping. - - 6. Otherwise, the top of memory is extended by - obtaining more space from the system (normally using sbrk, - but definable to anything else via the MORECORE macro). - Memory is gathered from the system (in system page-sized - units) in a way that allows chunks obtained across different - sbrk calls to be consolidated, but does not require - contiguous memory. Thus, it should be safe to intersperse - mallocs with other sbrk calls. - - - All allocations are made from the the `lowest' part of any found - chunk. (The implementation invariant is that prev_inuse is - always true of any allocated chunk; i.e., that each allocated - chunk borders either a previously allocated and still in-use chunk, - or the base of its memory arena.) - -*/ - -#if __STD_C -Void_t* mALLOc(RARG size_t bytes) -#else -Void_t* mALLOc(RARG bytes) RDECL size_t bytes; -#endif -{ -#ifdef MALLOC_PROVIDED - - return malloc (bytes); // Make sure that the pointer returned by malloc is returned back. - -#else - - mchunkptr victim; /* inspected/selected chunk */ - INTERNAL_SIZE_T victim_size; /* its size */ - int idx; /* index for bin traversal */ - mbinptr bin; /* associated bin */ - mchunkptr remainder; /* remainder from a split */ - long remainder_size; /* its size */ - int remainder_index; /* its bin index */ - unsigned long block; /* block traverser bit */ - int startidx; /* first bin of a traversed block */ - mchunkptr fwd; /* misc temp for linking */ - mchunkptr bck; /* misc temp for linking */ - mbinptr q; /* misc temp */ - - INTERNAL_SIZE_T nb = request2size(bytes); /* padded request size; */ - - /* Check for overflow and just fail, if so. */ - if (nb > INT_MAX || nb < bytes) - { - RERRNO = ENOMEM; - return 0; - } - - MALLOC_LOCK; - - /* Check for exact match in a bin */ - - if (is_small_request(nb)) /* Faster version for small requests */ - { - idx = smallbin_index(nb); - - /* No traversal or size check necessary for small bins. */ - - q = bin_at(idx); - victim = last(q); - -#if MALLOC_ALIGN != 16 - /* Also scan the next one, since it would have a remainder < MINSIZE */ - if (victim == q) - { - q = next_bin(q); - victim = last(q); - } -#endif - if (victim != q) - { - victim_size = chunksize(victim); - unlink(victim, bck, fwd); - set_inuse_bit_at_offset(victim, victim_size); - check_malloced_chunk(victim, nb); - MALLOC_UNLOCK; - return chunk2mem(victim); - } - - idx += 2; /* Set for bin scan below. We've already scanned 2 bins. */ - - } - else - { - idx = bin_index(nb); - bin = bin_at(idx); - - for (victim = last(bin); victim != bin; victim = victim->bk) - { - victim_size = chunksize(victim); - remainder_size = long_sub_size_t(victim_size, nb); - - if (remainder_size >= (long)MINSIZE) /* too big */ - { - --idx; /* adjust to rescan below after checking last remainder */ - break; - } - - else if (remainder_size >= 0) /* exact fit */ - { - unlink(victim, bck, fwd); - set_inuse_bit_at_offset(victim, victim_size); - check_malloced_chunk(victim, nb); - MALLOC_UNLOCK; - return chunk2mem(victim); - } - } - - ++idx; - - } - - /* Try to use the last split-off remainder */ - - if ( (victim = last_remainder->fd) != last_remainder) - { - victim_size = chunksize(victim); - remainder_size = long_sub_size_t(victim_size, nb); - - if (remainder_size >= (long)MINSIZE) /* re-split */ - { - remainder = chunk_at_offset(victim, nb); - set_head(victim, nb | PREV_INUSE); - link_last_remainder(remainder); - set_head(remainder, remainder_size | PREV_INUSE); - set_foot(remainder, remainder_size); - check_malloced_chunk(victim, nb); - MALLOC_UNLOCK; - return chunk2mem(victim); - } - - clear_last_remainder; - - if (remainder_size >= 0) /* exhaust */ - { - set_inuse_bit_at_offset(victim, victim_size); - check_malloced_chunk(victim, nb); - MALLOC_UNLOCK; - return chunk2mem(victim); - } - - /* Else place in bin */ - - frontlink(victim, victim_size, remainder_index, bck, fwd); - } - - /* - If there are any possibly nonempty big-enough blocks, - search for best fitting chunk by scanning bins in blockwidth units. - */ - - if ( (block = idx2binblock(idx)) <= binblocks) - { - - /* Get to the first marked block */ - - if ( (block & binblocks) == 0) - { - /* force to an even block boundary */ - idx = (idx & ~(BINBLOCKWIDTH - 1)) + BINBLOCKWIDTH; - block <<= 1; - while ((block & binblocks) == 0) - { - idx += BINBLOCKWIDTH; - block <<= 1; - } - } - - /* For each possibly nonempty block ... */ - for (;;) - { - startidx = idx; /* (track incomplete blocks) */ - q = bin = bin_at(idx); - - /* For each bin in this block ... */ - do - { - /* Find and use first big enough chunk ... */ - - for (victim = last(bin); victim != bin; victim = victim->bk) - { - victim_size = chunksize(victim); - remainder_size = long_sub_size_t(victim_size, nb); - - if (remainder_size >= (long)MINSIZE) /* split */ - { - remainder = chunk_at_offset(victim, nb); - set_head(victim, nb | PREV_INUSE); - unlink(victim, bck, fwd); - link_last_remainder(remainder); - set_head(remainder, remainder_size | PREV_INUSE); - set_foot(remainder, remainder_size); - check_malloced_chunk(victim, nb); - MALLOC_UNLOCK; - return chunk2mem(victim); - } - - else if (remainder_size >= 0) /* take */ - { - set_inuse_bit_at_offset(victim, victim_size); - unlink(victim, bck, fwd); - check_malloced_chunk(victim, nb); - MALLOC_UNLOCK; - return chunk2mem(victim); - } - - } - - bin = next_bin(bin); - -#if MALLOC_ALIGN == 16 - if (idx < MAX_SMALLBIN) - { - bin = next_bin(bin); - ++idx; - } -#endif - } while ((++idx & (BINBLOCKWIDTH - 1)) != 0); - - /* Clear out the block bit. */ - - do /* Possibly backtrack to try to clear a partial block */ - { - if ((startidx & (BINBLOCKWIDTH - 1)) == 0) - { - binblocks &= ~block; - break; - } - --startidx; - q = prev_bin(q); - } while (first(q) == q); - - /* Get to the next possibly nonempty block */ - - if ( (block <<= 1) <= binblocks && (block != 0) ) - { - while ((block & binblocks) == 0) - { - idx += BINBLOCKWIDTH; - block <<= 1; - } - } - else - break; - } - } - - - /* Try to use top chunk */ - - /* Require that there be a remainder, ensuring top always exists */ - remainder_size = long_sub_size_t(chunksize(top), nb); - if (chunksize(top) < nb || remainder_size < (long)MINSIZE) - { - -#if HAVE_MMAP - /* If big and would otherwise need to extend, try to use mmap instead */ - if ((unsigned long)nb >= (unsigned long)mmap_threshold && - (victim = mmap_chunk(nb)) != 0) - { - MALLOC_UNLOCK; - return chunk2mem(victim); - } -#endif - - /* Try to extend */ - malloc_extend_top(RCALL nb); - remainder_size = long_sub_size_t(chunksize(top), nb); - if (chunksize(top) < nb || remainder_size < (long)MINSIZE) - { - MALLOC_UNLOCK; - return 0; /* propagate failure */ - } - } - - victim = top; - set_head(victim, nb | PREV_INUSE); - top = chunk_at_offset(victim, nb); - set_head(top, remainder_size | PREV_INUSE); - check_malloced_chunk(victim, nb); - MALLOC_UNLOCK; - return chunk2mem(victim); - -#endif /* MALLOC_PROVIDED */ -} - -#endif /* DEFINE_MALLOC */ - -#ifdef DEFINE_FREE - -/* - - free() algorithm : - - cases: - - 1. free(0) has no effect. - - 2. If the chunk was allocated via mmap, it is release via munmap(). - - 3. If a returned chunk borders the current high end of memory, - it is consolidated into the top, and if the total unused - topmost memory exceeds the trim threshold, malloc_trim is - called. - - 4. Other chunks are consolidated as they arrive, and - placed in corresponding bins. (This includes the case of - consolidating with the current `last_remainder'). - -*/ - - -#if __STD_C -void fREe(RARG Void_t* mem) -#else -void fREe(RARG mem) RDECL Void_t* mem; -#endif -{ -#ifdef MALLOC_PROVIDED - - free (mem); - -#else - - mchunkptr p; /* chunk corresponding to mem */ - INTERNAL_SIZE_T hd; /* its head field */ - INTERNAL_SIZE_T sz; /* its size */ - int idx; /* its bin index */ - mchunkptr next; /* next contiguous chunk */ - INTERNAL_SIZE_T nextsz; /* its size */ - INTERNAL_SIZE_T prevsz; /* size of previous contiguous chunk */ - mchunkptr bck; /* misc temp for linking */ - mchunkptr fwd; /* misc temp for linking */ - int islr; /* track whether merging with last_remainder */ - - if (mem == 0) /* free(0) has no effect */ - return; - - MALLOC_LOCK; - - p = mem2chunk(mem); - hd = p->size; - -#if HAVE_MMAP - if (hd & IS_MMAPPED) /* release mmapped memory. */ - { - munmap_chunk(p); - MALLOC_UNLOCK; - return; - } -#endif - - check_inuse_chunk(p); - - sz = hd & ~PREV_INUSE; - next = chunk_at_offset(p, sz); - nextsz = chunksize(next); - - if (next == top) /* merge with top */ - { - sz += nextsz; - - if (!(hd & PREV_INUSE)) /* consolidate backward */ - { - prevsz = p->prev_size; - p = chunk_at_offset(p, -prevsz); - sz += prevsz; - unlink(p, bck, fwd); - } - - set_head(p, sz | PREV_INUSE); - top = p; - if ((unsigned long)(sz) >= (unsigned long)trim_threshold) - malloc_trim(RCALL top_pad); - MALLOC_UNLOCK; - return; - } - - set_head(next, nextsz); /* clear inuse bit */ - - islr = 0; - - if (!(hd & PREV_INUSE)) /* consolidate backward */ - { - prevsz = p->prev_size; - p = chunk_at_offset(p, -prevsz); - sz += prevsz; - - if (p->fd == last_remainder) /* keep as last_remainder */ - islr = 1; - else - unlink(p, bck, fwd); - } - - if (!(inuse_bit_at_offset(next, nextsz))) /* consolidate forward */ - { - sz += nextsz; - - if (!islr && next->fd == last_remainder) /* re-insert last_remainder */ - { - islr = 1; - link_last_remainder(p); - } - else - unlink(next, bck, fwd); - } - - - set_head(p, sz | PREV_INUSE); - set_foot(p, sz); - if (!islr) - frontlink(p, sz, idx, bck, fwd); - - MALLOC_UNLOCK; - -#endif /* MALLOC_PROVIDED */ -} - -#endif /* DEFINE_FREE */ - -#ifdef DEFINE_REALLOC - -/* - - Realloc algorithm: - - Chunks that were obtained via mmap cannot be extended or shrunk - unless HAVE_MREMAP is defined, in which case mremap is used. - Otherwise, if their reallocation is for additional space, they are - copied. If for less, they are just left alone. - - Otherwise, if the reallocation is for additional space, and the - chunk can be extended, it is, else a malloc-copy-free sequence is - taken. There are several different ways that a chunk could be - extended. All are tried: - - * Extending forward into following adjacent free chunk. - * Shifting backwards, joining preceding adjacent space - * Both shifting backwards and extending forward. - * Extending into newly sbrked space - - Unless the #define REALLOC_ZERO_BYTES_FREES is set, realloc with a - size argument of zero (re)allocates a minimum-sized chunk. - - If the reallocation is for less space, and the new request is for - a `small' (<512 bytes) size, then the newly unused space is lopped - off and freed. - - The old unix realloc convention of allowing the last-free'd chunk - to be used as an argument to realloc is no longer supported. - I don't know of any programs still relying on this feature, - and allowing it would also allow too many other incorrect - usages of realloc to be sensible. - - -*/ - - -#if __STD_C -Void_t* rEALLOc(RARG Void_t* oldmem, size_t bytes) -#else -Void_t* rEALLOc(RARG oldmem, bytes) RDECL Void_t* oldmem; size_t bytes; -#endif -{ -#ifdef MALLOC_PROVIDED - - realloc (oldmem, bytes); - -#else - - INTERNAL_SIZE_T nb; /* padded request size */ - - mchunkptr oldp; /* chunk corresponding to oldmem */ - INTERNAL_SIZE_T oldsize; /* its size */ - - mchunkptr newp; /* chunk to return */ - INTERNAL_SIZE_T newsize; /* its size */ - Void_t* newmem; /* corresponding user mem */ - - mchunkptr next; /* next contiguous chunk after oldp */ - INTERNAL_SIZE_T nextsize; /* its size */ - - mchunkptr prev; /* previous contiguous chunk before oldp */ - INTERNAL_SIZE_T prevsize; /* its size */ - - mchunkptr remainder; /* holds split off extra space from newp */ - INTERNAL_SIZE_T remainder_size; /* its size */ - - mchunkptr bck; /* misc temp for linking */ - mchunkptr fwd; /* misc temp for linking */ - -#ifdef REALLOC_ZERO_BYTES_FREES - if (bytes == 0) { fREe(RCALL oldmem); return 0; } -#endif - - - /* realloc of null is supposed to be same as malloc */ - if (oldmem == 0) return mALLOc(RCALL bytes); - - MALLOC_LOCK; - - newp = oldp = mem2chunk(oldmem); - newsize = oldsize = chunksize(oldp); - - - nb = request2size(bytes); - - /* Check for overflow and just fail, if so. */ - if (nb > INT_MAX || nb < bytes) - { - RERRNO = ENOMEM; - return 0; - } - -#if HAVE_MMAP - if (chunk_is_mmapped(oldp)) - { -#if HAVE_MREMAP - newp = mremap_chunk(oldp, nb); - if(newp) - { - MALLOC_UNLOCK; - return chunk2mem(newp); - } -#endif - /* Note the extra SIZE_SZ overhead. */ - if(oldsize - SIZE_SZ >= nb) - { - MALLOC_UNLOCK; - return oldmem; /* do nothing */ - } - /* Must alloc, copy, free. */ - newmem = mALLOc(RCALL bytes); - if (newmem == 0) - { - MALLOC_UNLOCK; - return 0; /* propagate failure */ - } - MALLOC_COPY(newmem, oldmem, oldsize - 2*SIZE_SZ); - munmap_chunk(oldp); - MALLOC_UNLOCK; - return newmem; - } -#endif - - check_inuse_chunk(oldp); - - if ((long)(oldsize) < (long)(nb)) - { - - /* Try expanding forward */ - - next = chunk_at_offset(oldp, oldsize); - if (next == top || !inuse(next)) - { - nextsize = chunksize(next); - - /* Forward into top only if a remainder */ - if (next == top) - { - if ((long)(nextsize + newsize) >= (long)(nb + MINSIZE)) - { - newsize += nextsize; - top = chunk_at_offset(oldp, nb); - set_head(top, (newsize - nb) | PREV_INUSE); - set_head_size(oldp, nb); - MALLOC_UNLOCK; - return chunk2mem(oldp); - } - } - - /* Forward into next chunk */ - else if (((long)(nextsize + newsize) >= (long)(nb))) - { - unlink(next, bck, fwd); - newsize += nextsize; - goto split; - } - } - else - { - next = 0; - nextsize = 0; - } - - /* Try shifting backwards. */ - - if (!prev_inuse(oldp)) - { - prev = prev_chunk(oldp); - prevsize = chunksize(prev); - - /* try forward + backward first to save a later consolidation */ - - if (next != 0) - { - /* into top */ - if (next == top) - { - if ((long)(nextsize + prevsize + newsize) >= (long)(nb + MINSIZE)) - { - unlink(prev, bck, fwd); - newp = prev; - newsize += prevsize + nextsize; - newmem = chunk2mem(newp); - MALLOC_COPY(newmem, oldmem, oldsize - SIZE_SZ); - top = chunk_at_offset(newp, nb); - set_head(top, (newsize - nb) | PREV_INUSE); - set_head_size(newp, nb); - MALLOC_UNLOCK; - return newmem; - } - } - - /* into next chunk */ - else if (((long)(nextsize + prevsize + newsize) >= (long)(nb))) - { - unlink(next, bck, fwd); - unlink(prev, bck, fwd); - newp = prev; - newsize += nextsize + prevsize; - newmem = chunk2mem(newp); - MALLOC_COPY(newmem, oldmem, oldsize - SIZE_SZ); - goto split; - } - } - - /* backward only */ - if (prev != 0 && (long)(prevsize + newsize) >= (long)nb) - { - unlink(prev, bck, fwd); - newp = prev; - newsize += prevsize; - newmem = chunk2mem(newp); - MALLOC_COPY(newmem, oldmem, oldsize - SIZE_SZ); - goto split; - } - } - - /* Must allocate */ - - newmem = mALLOc (RCALL bytes); - - if (newmem == 0) /* propagate failure */ - { - MALLOC_UNLOCK; - return 0; - } - - /* Avoid copy if newp is next chunk after oldp. */ - /* (This can only happen when new chunk is sbrk'ed.) */ - - if ( (newp = mem2chunk(newmem)) == next_chunk(oldp)) - { - newsize += chunksize(newp); - newp = oldp; - goto split; - } - - /* Otherwise copy, free, and exit */ - MALLOC_COPY(newmem, oldmem, oldsize - SIZE_SZ); - fREe(RCALL oldmem); - MALLOC_UNLOCK; - return newmem; - } - - - split: /* split off extra room in old or expanded chunk */ - - remainder_size = long_sub_size_t(newsize, nb); - - if (remainder_size >= (long)MINSIZE) /* split off remainder */ - { - remainder = chunk_at_offset(newp, nb); - set_head_size(newp, nb); - set_head(remainder, remainder_size | PREV_INUSE); - set_inuse_bit_at_offset(remainder, remainder_size); - fREe(RCALL chunk2mem(remainder)); /* let free() deal with it */ - } - else - { - set_head_size(newp, newsize); - set_inuse_bit_at_offset(newp, newsize); - } - - check_inuse_chunk(newp); - MALLOC_UNLOCK; - return chunk2mem(newp); - -#endif /* MALLOC_PROVIDED */ -} - -#endif /* DEFINE_REALLOC */ - -#ifdef DEFINE_MEMALIGN - -/* - - memalign algorithm: - - memalign requests more than enough space from malloc, finds a spot - within that chunk that meets the alignment request, and then - possibly frees the leading and trailing space. - - The alignment argument must be a power of two. This property is not - checked by memalign, so misuse may result in random runtime errors. - - 8-byte alignment is guaranteed by normal malloc calls, so don't - bother calling memalign with an argument of 8 or less. - - Overreliance on memalign is a sure way to fragment space. - -*/ - - -#if __STD_C -Void_t* mEMALIGn(RARG size_t alignment, size_t bytes) -#else -Void_t* mEMALIGn(RARG alignment, bytes) RDECL size_t alignment; size_t bytes; -#endif -{ - INTERNAL_SIZE_T nb; /* padded request size */ - char* m; /* memory returned by malloc call */ - mchunkptr p; /* corresponding chunk */ - char* brk; /* alignment point within p */ - mchunkptr newp; /* chunk to return */ - INTERNAL_SIZE_T newsize; /* its size */ - INTERNAL_SIZE_T leadsize; /* leading space befor alignment point */ - mchunkptr remainder; /* spare room at end to split off */ - long remainder_size; /* its size */ - - /* If need less alignment than we give anyway, just relay to malloc */ - - if (alignment <= MALLOC_ALIGNMENT) return mALLOc(RCALL bytes); - - /* Otherwise, ensure that it is at least a minimum chunk size */ - - if (alignment < MINSIZE) alignment = MINSIZE; - - /* Call malloc with worst case padding to hit alignment. */ - - nb = request2size(bytes); - - /* Check for overflow. */ - if (nb > __SIZE_MAX__ - (alignment + MINSIZE) || nb < bytes) - { - RERRNO = ENOMEM; - return 0; - } - - m = (char*)(mALLOc(RCALL nb + alignment + MINSIZE)); - - if (m == 0) return 0; /* propagate failure */ - - MALLOC_LOCK; - - p = mem2chunk(m); - - if ((((unsigned long)(m)) % alignment) == 0) /* aligned */ - { -#if HAVE_MMAP - if(chunk_is_mmapped(p)) - { - MALLOC_UNLOCK; - return chunk2mem(p); /* nothing more to do */ - } -#endif - } - else /* misaligned */ - { - /* - Find an aligned spot inside chunk. - Since we need to give back leading space in a chunk of at - least MINSIZE, if the first calculation places us at - a spot with less than MINSIZE leader, we can move to the - next aligned spot -- we've allocated enough total room so that - this is always possible. - */ - - brk = (char*)mem2chunk(((unsigned long)(m + alignment - 1)) & -alignment); - if ((long)(brk - (char*)(p)) < (long)MINSIZE) brk = brk + alignment; - - newp = (mchunkptr)brk; - leadsize = brk - (char*)(p); - newsize = chunksize(p) - leadsize; - -#if HAVE_MMAP - if(chunk_is_mmapped(p)) - { - newp->prev_size = p->prev_size + leadsize; - set_head(newp, newsize|IS_MMAPPED); - MALLOC_UNLOCK; - return chunk2mem(newp); - } -#endif - - /* give back leader, use the rest */ - - set_head(newp, newsize | PREV_INUSE); - set_inuse_bit_at_offset(newp, newsize); - set_head_size(p, leadsize); - fREe(RCALL chunk2mem(p)); - p = newp; - - assert (newsize >= nb && (((unsigned long)(chunk2mem(p))) % alignment) == 0); - } - - /* Also give back spare room at the end */ - - remainder_size = long_sub_size_t(chunksize(p), nb); - - if (remainder_size >= (long)MINSIZE) - { - remainder = chunk_at_offset(p, nb); - set_head(remainder, remainder_size | PREV_INUSE); - set_head_size(p, nb); - fREe(RCALL chunk2mem(remainder)); - } - - check_inuse_chunk(p); - MALLOC_UNLOCK; - return chunk2mem(p); - -} - -#endif /* DEFINE_MEMALIGN */ - -#ifdef DEFINE_VALLOC - -/* - valloc just invokes memalign with alignment argument equal - to the page size of the system (or as near to this as can - be figured out from all the includes/defines above.) -*/ - -#if __STD_C -Void_t* vALLOc(RARG size_t bytes) -#else -Void_t* vALLOc(RARG bytes) RDECL size_t bytes; -#endif -{ - return mEMALIGn (RCALL malloc_getpagesize, bytes); -} - -#endif /* DEFINE_VALLOC */ - -#ifdef DEFINE_PVALLOC - -/* - pvalloc just invokes valloc for the nearest pagesize - that will accommodate request -*/ - - -#if __STD_C -Void_t* pvALLOc(RARG size_t bytes) -#else -Void_t* pvALLOc(RARG bytes) RDECL size_t bytes; -#endif -{ - size_t pagesize = malloc_getpagesize; - if (bytes > __SIZE_MAX__ - pagesize) - { - RERRNO = ENOMEM; - return 0; - } - return mEMALIGn (RCALL pagesize, (bytes + pagesize - 1) & ~(pagesize - 1)); -} - -#endif /* DEFINE_PVALLOC */ - -#ifdef DEFINE_CALLOC - -/* - - calloc calls malloc, then zeroes out the allocated chunk. - -*/ - -#if __STD_C -Void_t* cALLOc(RARG size_t n, size_t elem_size) -#else -Void_t* cALLOc(RARG n, elem_size) RDECL size_t n; size_t elem_size; -#endif -{ - mchunkptr p; - INTERNAL_SIZE_T csz; - - INTERNAL_SIZE_T sz; - -#if MORECORE_CLEARS - mchunkptr oldtop; - INTERNAL_SIZE_T oldtopsize; -#endif - Void_t* mem; - - if (__builtin_mul_overflow((INTERNAL_SIZE_T) n, (INTERNAL_SIZE_T) elem_size, &sz)) - { - errno = ENOMEM; - return 0; - } - - /* check if expand_top called, in which case don't need to clear */ -#if MORECORE_CLEARS - MALLOC_LOCK; - oldtop = top; - oldtopsize = chunksize(top); -#endif - - mem = mALLOc (RCALL sz); - - if (mem == 0) - { -#if MORECORE_CLEARS - MALLOC_UNLOCK; -#endif - return 0; - } - else - { - p = mem2chunk(mem); - - /* Two optional cases in which clearing not necessary */ - - -#if HAVE_MMAP - if (chunk_is_mmapped(p)) - { -#if MORECORE_CLEARS - MALLOC_UNLOCK; -#endif - return mem; - } -#endif - - csz = chunksize(p); - -#if MORECORE_CLEARS - if (p == oldtop && csz > oldtopsize) - { - /* clear only the bytes from non-freshly-sbrked memory */ - csz = oldtopsize; - } - MALLOC_UNLOCK; -#endif - - MALLOC_ZERO(mem, csz - SIZE_SZ); - return mem; - } -} - -#endif /* DEFINE_CALLOC */ - -#if defined(DEFINE_CFREE) && !defined(__CYGWIN__) - -/* - - cfree just calls free. It is needed/defined on some systems - that pair it with calloc, presumably for odd historical reasons. - -*/ - -#if !defined(INTERNAL_LINUX_C_LIB) || !defined(__ELF__) -#if !defined(_LIBC) || !defined(_REENT_ONLY) -#if __STD_C -void cfree(Void_t *mem) -#else -void cfree(mem) Void_t *mem; -#endif -{ -#ifdef _LIBC - fREe(_REENT, mem); -#else - fREe(mem); -#endif -} -#endif -#endif - -#endif /* DEFINE_CFREE */ - -#ifdef DEFINE_FREE - -/* - - Malloc_trim gives memory back to the system (via negative - arguments to sbrk) if there is unused memory at the `high' end of - the malloc pool. You can call this after freeing large blocks of - memory to potentially reduce the system-level memory requirements - of a program. However, it cannot guarantee to reduce memory. Under - some allocation patterns, some large free blocks of memory will be - locked between two used chunks, so they cannot be given back to - the system. - - The `pad' argument to malloc_trim represents the amount of free - trailing space to leave untrimmed. If this argument is zero, - only the minimum amount of memory to maintain internal data - structures will be left (one page or less). Non-zero arguments - can be supplied to maintain enough trailing space to service - future expected allocations without having to re-obtain memory - from the system. - - Malloc_trim returns 1 if it actually released any memory, else 0. - -*/ - -#if __STD_C -int malloc_trim(RARG size_t pad) -#else -int malloc_trim(RARG pad) RDECL size_t pad; -#endif -{ - long top_size; /* Amount of top-most memory */ - long extra; /* Amount to release */ - char* current_brk; /* address returned by pre-check sbrk call */ - char* new_brk; /* address returned by negative sbrk call */ - - unsigned long pagesz = malloc_getpagesize; - - MALLOC_LOCK; - - top_size = chunksize(top); - extra = ((top_size - pad - MINSIZE + (pagesz-1)) / pagesz - 1) * pagesz; - - if (extra < (long)pagesz) /* Not enough memory to release */ - { - MALLOC_UNLOCK; - return 0; - } - - else - { - /* Test to make sure no one else called sbrk */ - current_brk = (char*)(MORECORE (0)); - if (current_brk != (char*)(top) + top_size) - { - MALLOC_UNLOCK; - return 0; /* Apparently we don't own memory; must fail */ - } - - else - { - new_brk = (char*)(MORECORE (-extra)); - - if (new_brk == (char*)(MORECORE_FAILURE)) /* sbrk failed? */ - { - /* Try to figure out what we have */ - current_brk = (char*)(MORECORE (0)); - top_size = current_brk - (char*)top; - if (top_size >= (long)MINSIZE) /* if not, we are very very dead! */ - { - sbrked_mem = current_brk - sbrk_base; - set_head(top, top_size | PREV_INUSE); - } - check_chunk(top); - MALLOC_UNLOCK; - return 0; - } - - else - { - /* Success. Adjust top accordingly. */ - set_head(top, (top_size - extra) | PREV_INUSE); - sbrked_mem -= extra; - check_chunk(top); - MALLOC_UNLOCK; - return 1; - } - } - } -} - -#endif /* DEFINE_FREE */ - -#ifdef DEFINE_MALLOC_USABLE_SIZE - -/* - malloc_usable_size: - - This routine tells you how many bytes you can actually use in an - allocated chunk, which may be more than you requested (although - often not). You can use this many bytes without worrying about - overwriting other allocated objects. Not a particularly great - programming practice, but still sometimes useful. - -*/ - -#if __STD_C -size_t malloc_usable_size(RARG Void_t* mem) -#else -size_t malloc_usable_size(RARG mem) RDECL Void_t* mem; -#endif -{ - mchunkptr p; - if (mem == 0) - return 0; - else - { - p = mem2chunk(mem); - if(!chunk_is_mmapped(p)) - { - if (!inuse(p)) return 0; -#if DEBUG - MALLOC_LOCK; - check_inuse_chunk(p); - MALLOC_UNLOCK; -#endif - return chunksize(p) - SIZE_SZ; - } - return chunksize(p) - 2*SIZE_SZ; - } -} - -#endif /* DEFINE_MALLOC_USABLE_SIZE */ - -#ifdef DEFINE_MALLINFO - -/* Utility to update current_mallinfo for malloc_stats and mallinfo() */ - -STATIC void malloc_update_mallinfo() -{ - int i; - mbinptr b; - mchunkptr p; -#if DEBUG - mchunkptr q; -#endif - - INTERNAL_SIZE_T avail = chunksize(top); - int navail = ((long)(avail) >= (long)MINSIZE)? 1 : 0; - - for (i = 1; i < NAV; ++i) - { - b = bin_at(i); - for (p = last(b); p != b; p = p->bk) - { -#if DEBUG - check_free_chunk(p); - for (q = next_chunk(p); - q < top && inuse(q) && (long)(chunksize(q)) >= (long)MINSIZE; - q = next_chunk(q)) - check_inuse_chunk(q); -#endif - avail += chunksize(p); - navail++; - } - } - - current_mallinfo.ordblks = navail; - current_mallinfo.uordblks = sbrked_mem - avail; - current_mallinfo.fordblks = avail; -#if HAVE_MMAP - current_mallinfo.hblks = n_mmaps; - current_mallinfo.hblkhd = mmapped_mem; -#endif - current_mallinfo.keepcost = chunksize(top); - -} - -#else /* ! DEFINE_MALLINFO */ - -#if __STD_C -extern void malloc_update_mallinfo(void); -#else -extern void malloc_update_mallinfo(); -#endif - -#endif /* ! DEFINE_MALLINFO */ - -#ifdef DEFINE_MALLOC_STATS - -/* - - malloc_stats: - - Prints on stderr the amount of space obtain from the system (both - via sbrk and mmap), the maximum amount (which may be more than - current if malloc_trim and/or munmap got called), the maximum - number of simultaneous mmap regions used, and the current number - of bytes allocated via malloc (or realloc, etc) but not yet - freed. (Note that this is the number of bytes allocated, not the - number requested. It will be larger than the number requested - because of alignment and bookkeeping overhead.) - -*/ - -#if __STD_C -void malloc_stats(RONEARG) -#else -void malloc_stats(RONEARG) RDECL -#endif -{ - unsigned long local_max_total_mem; - int local_sbrked_mem; - struct mallinfo local_mallinfo; -#if HAVE_MMAP - unsigned long local_mmapped_mem, local_max_n_mmaps; -#endif - FILE *fp; - - MALLOC_LOCK; - malloc_update_mallinfo(); - local_max_total_mem = max_total_mem; - local_sbrked_mem = sbrked_mem; - local_mallinfo = current_mallinfo; -#if HAVE_MMAP - local_mmapped_mem = mmapped_mem; - local_max_n_mmaps = max_n_mmaps; -#endif - MALLOC_UNLOCK; - -#ifdef _LIBC - _REENT_SMALL_CHECK_INIT(reent_ptr); - fp = _stderr_r(reent_ptr); -#define fprintf fiprintf -#else - fp = stderr; -#endif - - fprintf(fp, "max system bytes = %10u\n", - (unsigned int)(local_max_total_mem)); -#if HAVE_MMAP - fprintf(fp, "system bytes = %10u\n", - (unsigned int)(local_sbrked_mem + local_mmapped_mem)); - fprintf(fp, "in use bytes = %10u\n", - (unsigned int)(local_mallinfo.uordblks + local_mmapped_mem)); -#else - fprintf(fp, "system bytes = %10u\n", - (unsigned int)local_sbrked_mem); - fprintf(fp, "in use bytes = %10u\n", - (unsigned int)local_mallinfo.uordblks); -#endif -#if HAVE_MMAP - fprintf(fp, "max mmap regions = %10u\n", - (unsigned int)local_max_n_mmaps); -#endif -} - -#endif /* DEFINE_MALLOC_STATS */ - -#ifdef DEFINE_MALLINFO - -/* - mallinfo returns a copy of updated current mallinfo. -*/ - -#if __STD_C -struct mallinfo mALLINFo(RONEARG) -#else -struct mallinfo mALLINFo(RONEARG) RDECL -#endif -{ - struct mallinfo ret; - - MALLOC_LOCK; - malloc_update_mallinfo(); - ret = current_mallinfo; - MALLOC_UNLOCK; - return ret; -} - -#endif /* DEFINE_MALLINFO */ - -#ifdef DEFINE_MALLOPT - -/* - mallopt: - - mallopt is the general SVID/XPG interface to tunable parameters. - The format is to provide a (parameter-number, parameter-value) pair. - mallopt then sets the corresponding parameter to the argument - value if it can (i.e., so long as the value is meaningful), - and returns 1 if successful else 0. - - See descriptions of tunable parameters above. - -*/ - -#if __STD_C -int mALLOPt(RARG int param_number, int value) -#else -int mALLOPt(RARG param_number, value) RDECL int param_number; int value; -#endif -{ - MALLOC_LOCK; - switch(param_number) - { - case M_TRIM_THRESHOLD: - trim_threshold = value; MALLOC_UNLOCK; return 1; - case M_TOP_PAD: - top_pad = value; MALLOC_UNLOCK; return 1; - case M_MMAP_THRESHOLD: -#if HAVE_MMAP - mmap_threshold = value; -#endif - MALLOC_UNLOCK; - return 1; - case M_MMAP_MAX: -#if HAVE_MMAP - n_mmaps_max = value; MALLOC_UNLOCK; return 1; -#else - MALLOC_UNLOCK; return value == 0; -#endif - - default: - MALLOC_UNLOCK; - return 0; - } -} - -#endif /* DEFINE_MALLOPT */ - -/* - -History: - - V2.6.5 Wed Jun 17 15:57:31 1998 Doug Lea (dl at gee) - * Fixed ordering problem with boundary-stamping - - V2.6.3 Sun May 19 08:17:58 1996 Doug Lea (dl at gee) - * Added pvalloc, as recommended by H.J. Liu - * Added 64bit pointer support mainly from Wolfram Gloger - * Added anonymously donated WIN32 sbrk emulation - * Malloc, calloc, getpagesize: add optimizations from Raymond Nijssen - * malloc_extend_top: fix mask error that caused wastage after - foreign sbrks - * Add linux mremap support code from HJ Liu - - V2.6.2 Tue Dec 5 06:52:55 1995 Doug Lea (dl at gee) - * Integrated most documentation with the code. - * Add support for mmap, with help from - Wolfram Gloger (Gloger@lrz.uni-muenchen.de). - * Use last_remainder in more cases. - * Pack bins using idea from colin@nyx10.cs.du.edu - * Use ordered bins instead of best-fit threshhold - * Eliminate block-local decls to simplify tracing and debugging. - * Support another case of realloc via move into top - * Fix error occuring when initial sbrk_base not word-aligned. - * Rely on page size for units instead of SBRK_UNIT to - avoid surprises about sbrk alignment conventions. - * Add mallinfo, mallopt. Thanks to Raymond Nijssen - (raymond@es.ele.tue.nl) for the suggestion. - * Add `pad' argument to malloc_trim and top_pad mallopt parameter. - * More precautions for cases where other routines call sbrk, - courtesy of Wolfram Gloger (Gloger@lrz.uni-muenchen.de). - * Added macros etc., allowing use in linux libc from - H.J. Lu (hjl@gnu.ai.mit.edu) - * Inverted this history list - - V2.6.1 Sat Dec 2 14:10:57 1995 Doug Lea (dl at gee) - * Re-tuned and fixed to behave more nicely with V2.6.0 changes. - * Removed all preallocation code since under current scheme - the work required to undo bad preallocations exceeds - the work saved in good cases for most test programs. - * No longer use return list or unconsolidated bins since - no scheme using them consistently outperforms those that don't - given above changes. - * Use best fit for very large chunks to prevent some worst-cases. - * Added some support for debugging - - V2.6.0 Sat Nov 4 07:05:23 1995 Doug Lea (dl at gee) - * Removed footers when chunks are in use. Thanks to - Paul Wilson (wilson@cs.texas.edu) for the suggestion. - - V2.5.4 Wed Nov 1 07:54:51 1995 Doug Lea (dl at gee) - * Added malloc_trim, with help from Wolfram Gloger - (wmglo@Dent.MED.Uni-Muenchen.DE). - - V2.5.3 Tue Apr 26 10:16:01 1994 Doug Lea (dl at g) - - V2.5.2 Tue Apr 5 16:20:40 1994 Doug Lea (dl at g) - * realloc: try to expand in both directions - * malloc: swap order of clean-bin strategy; - * realloc: only conditionally expand backwards - * Try not to scavenge used bins - * Use bin counts as a guide to preallocation - * Occasionally bin return list chunks in first scan - * Add a few optimizations from colin@nyx10.cs.du.edu - - V2.5.1 Sat Aug 14 15:40:43 1993 Doug Lea (dl at g) - * faster bin computation & slightly different binning - * merged all consolidations to one part of malloc proper - (eliminating old malloc_find_space & malloc_clean_bin) - * Scan 2 returns chunks (not just 1) - * Propagate failure in realloc if malloc returns 0 - * Add stuff to allow compilation on non-ANSI compilers - from kpv@research.att.com - - V2.5 Sat Aug 7 07:41:59 1993 Doug Lea (dl at g.oswego.edu) - * removed potential for odd address access in prev_chunk - * removed dependency on getpagesize.h - * misc cosmetics and a bit more internal documentation - * anticosmetics: mangled names in macros to evade debugger strangeness - * tested on sparc, hp-700, dec-mips, rs6000 - with gcc & native cc (hp, dec only) allowing - Detlefs & Zorn comparison study (in SIGPLAN Notices.) - - Trial version Fri Aug 28 13:14:29 1992 Doug Lea (dl at g.oswego.edu) - * Based loosely on libg++-1.2X malloc. (It retains some of the overall - structure of old version, but most details differ.) - -*/ -#endif -- cgit v1.1