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author | David Henkel-Wallace <gumby@cygnus> | 1991-03-21 21:29:07 +0000 |
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committer | David Henkel-Wallace <gumby@cygnus> | 1991-03-21 21:29:07 +0000 |
commit | c074abeebcefe3b62f46ff8a62f3d4058ed32780 (patch) | |
tree | 97a36afc00d9cc840b84d89e40ffbd13cd3ad7f7 /binutils/gmalloc.c | |
parent | 2fa0b342a5cd580781d2b9348a87f33a92d363fa (diff) | |
download | gdb-c074abeebcefe3b62f46ff8a62f3d4058ed32780.zip gdb-c074abeebcefe3b62f46ff8a62f3d4058ed32780.tar.gz gdb-c074abeebcefe3b62f46ff8a62f3d4058ed32780.tar.bz2 |
Back from Intel with Steve
Diffstat (limited to 'binutils/gmalloc.c')
-rw-r--r-- | binutils/gmalloc.c | 1116 |
1 files changed, 1116 insertions, 0 deletions
diff --git a/binutils/gmalloc.c b/binutils/gmalloc.c new file mode 100644 index 0000000..0468551 --- /dev/null +++ b/binutils/gmalloc.c @@ -0,0 +1,1116 @@ + +/* gmalloc.c - THIS FILE IS AUTOMAGICALLY GENERATED SO DON'T EDIT IT. */ + +/* Single-file skeleton for GNU malloc. + Copyright 1989 Free Software Foundation + Written May 1989 by Mike Haertel. + + This program is free software; you can redistribute it and/or modify + it under the terms of the GNU General Public License as published by + the Free Software Foundation; either version 1, or (at your option) + any later version. + + This program is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + GNU General Public License for more details. + + You should have received a copy of the GNU General Public License + along with this program; if not, write to the Free Software + Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. + + The author may be reached (Email) at the address mike@ai.mit.edu, + or (US mail) as Mike Haertel c/o Free Software Foundation. */ + +#define __ONEFILE + +/* DO NOT DELETE THIS LINE -- ansidecl.h INSERTED HERE. */ +/* Copyright (C) 1989 Free Software Foundation, Inc. +This file is part of the GNU C Library. + +The GNU C Library is free software; you can redistribute it and/or modify +it under the terms of the GNU General Public License as published by +the Free Software Foundation; either version 1, or (at your option) +any later version. + +The GNU C Library is distributed in the hope that it will be useful, +but WITHOUT ANY WARRANTY; without even the implied warranty of +MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +GNU General Public License for more details. + +You should have received a copy of the GNU General Public License +along with the GNU C Library; see the file COPYING. If not, write to +the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA. */ + +/* ANSI and traditional C compatibility macros + + ANSI C is assumed if __STDC__ is #defined. + + Macros + PTR - Generic pointer type + LONG_DOUBLE - `long double' type + CONST - `const' keyword + VOLATILE - `volatile' keyword + SIGNED - `signed' keyword + PTRCONST - Generic const pointer (void *const) + + EXFUN(name, prototype) - declare external function NAME + with prototype PROTOTYPE + DEFUN(name, arglist, args) - define function NAME with + args ARGLIST of types in ARGS + DEFUN_VOID(name) - define function NAME with no args + AND - argument separator for ARGS + NOARGS - null arglist + DOTS - `...' in args + + For example: + extern int EXFUN(printf, (CONST char *format DOTS)); + int DEFUN(fprintf, (stream, format), + FILE *stream AND CONST char *format DOTS) { ... } + void DEFUN_VOID(abort) { ... } +*/ + +#ifndef _ANSIDECL_H + +#define _ANSIDECL_H 1 + + +/* Every source file includes this file, + so they will all get the switch for lint. */ +/* LINTLIBRARY */ + + +#ifdef __STDC__ + +#define PTR void * +#define PTRCONST void *CONST +#define LONG_DOUBLE long double + +#define AND , +#define NOARGS void +#define CONST const +#define VOLATILE volatile +#define SIGNED signed +#define DOTS , ... + +#define EXFUN(name, proto) name proto +#define DEFUN(name, arglist, args) name(args) +#define DEFUN_VOID(name) name(NOARGS) + +#else /* Not ANSI C. */ + +#define PTR char * +#define PTRCONST PTR +#define LONG_DOUBLE double + +#define AND ; +#define NOARGS +#define CONST +#define VOLATILE +#define SIGNED +#define DOTS + +#define EXFUN(name, proto) name() +#define DEFUN(name, arglist, args) name arglist args; +#define DEFUN_VOID(name) name() + +#endif /* ANSI C. */ + + +#endif /* ansidecl.h */ + +#ifdef __STDC__ +#include <limits.h> +#else +/* DO NOT DELETE THIS LINE -- limits.h INSERTED HERE. */ +/* Number of bits in a `char'. */ +#define CHAR_BIT 8 + +/* No multibyte characters supported yet. */ +#define MB_LEN_MAX 1 + +/* Minimum and maximum values a `signed char' can hold. */ +#define SCHAR_MIN -128 +#define SCHAR_MAX 127 + +/* Maximum value an `unsigned char' can hold. (Minimum is 0). */ +#define UCHAR_MAX 255U + +/* Minimum and maximum values a `char' can hold. */ +#ifdef __CHAR_UNSIGNED__ +#define CHAR_MIN 0 +#define CHAR_MAX 255U +#else +#define CHAR_MIN -128 +#define CHAR_MAX 127 +#endif + +/* Minimum and maximum values a `signed short int' can hold. */ +#define SHRT_MIN -32768 +#define SHRT_MAX 32767 + +/* Maximum value an `unsigned short int' can hold. (Minimum is 0). */ +#define USHRT_MAX 65535U + +/* Minimum and maximum values a `signed int' can hold. */ +#define INT_MIN -2147483648 +#define INT_MAX 2147483647 + +/* Maximum value an `unsigned int' can hold. (Minimum is 0). */ +#define UINT_MAX 4294967295U + +/* Minimum and maximum values a `signed long int' can hold. + (Same as `int'). */ +#define LONG_MIN (-LONG_MAX-1) +#define LONG_MAX 2147483647 + +/* Maximum value an `unsigned long int' can hold. (Minimum is 0). */ +#define ULONG_MAX 4294967295U +#endif + +#ifdef __STDC__ +#include <stddef.h> +#else +/* DO NOT DELETE THIS LINE -- stddef.h INSERTED HERE. */ +#ifndef _STDDEF_H +#define _STDDEF_H + +/* Signed type of difference of two pointers. */ + +typedef long ptrdiff_t; + +/* Unsigned type of `sizeof' something. */ + +#ifndef _SIZE_T /* in case <sys/types.h> has defined it. */ +#define _SIZE_T +typedef unsigned long size_t; +#endif /* _SIZE_T */ + +/* A null pointer constant. */ + +#undef NULL /* in case <stdio.h> has defined it. */ +#define NULL 0 + +/* Offset of member MEMBER in a struct of type TYPE. */ + +#define offsetof(TYPE, MEMBER) ((size_t) &((TYPE *)0)->MEMBER) + +#endif /* _STDDEF_H */ +#endif + +/* DO NOT DELETE THIS LINE -- stdlib.h INSERTED HERE. */ +/* Fake stdlib.h supplying the stuff needed by malloc. */ + +#ifndef __ONEFILE +#include <stddef.h> +#endif + +extern void EXFUN(abort, (void)); +extern void EXFUN(free, (PTR)); +extern PTR EXFUN(malloc, (size_t)); +extern PTR EXFUN(realloc, (PTR, size_t)); + +/* DO NOT DELETE THIS LINE -- string.h INSERTED HERE. */ +/* Fake string.h supplying stuff used by malloc. */ +#ifndef __ONEFILE +#include <stddef.h> +#endif + +extern PTR EXFUN(memcpy, (PTR, PTR, size_t)); +extern PTR EXFUN(memset, (PTR, int, size_t)); +#define memmove memcpy + +#define _MALLOC_INTERNAL +/* DO NOT DELETE THIS LINE -- malloc.h INSERTED HERE. */ +/* Declarations for `malloc' and friends. + Copyright 1990 Free Software Foundation + Written May 1989 by Mike Haertel. + + This program is free software; you can redistribute it and/or modify + it under the terms of the GNU General Public License as published by + the Free Software Foundation; either version 1, or (at your option) + any later version. + + This program is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + GNU General Public License for more details. + + You should have received a copy of the GNU General Public License + along with this program; if not, write to the Free Software + Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. + + The author may be reached (Email) at the address mike@@ai.mit.edu, + or (US mail) as Mike Haertel c/o Free Software Foundation. */ + +#ifndef _MALLOC_H + +#define _MALLOC_H 1 + +#ifndef __ONEFILE +#define __need_NULL +#define __need_size_t +#define __need_ptrdiff_t +#include <stddef.h> +#endif + +#ifdef _MALLOC_INTERNAL + +#ifndef __ONEFILE +#include <limits.h> +#endif + +/* The allocator divides the heap into blocks of fixed size; large + requests receive one or more whole blocks, and small requests + receive a fragment of a block. Fragment sizes are powers of two, + and all fragments of a block are the same size. When all the + fragments in a block have been freed, the block itself is freed. */ +#define INT_BIT (CHAR_BIT * sizeof(int)) +#define BLOCKLOG (INT_BIT > 16 ? 12 : 9) +#define BLOCKSIZE (1 << BLOCKLOG) +#define BLOCKIFY(SIZE) (((SIZE) + BLOCKSIZE - 1) / BLOCKSIZE) + +/* Determine the amount of memory spanned by the initial heap table + (not an absolute limit). */ +#define HEAP (INT_BIT > 16 ? 4194304 : 65536) + +/* Number of contiguous free blocks allowed to build up at the end of + memory before they will be returned to the system. */ +#define FINAL_FREE_BLOCKS 8 + +/* Where to start searching the free list when looking for new memory. + The two possible values are 0 and _heapindex. Starting at 0 seems + to reduce total memory usage, while starting at _heapindex seems to + run faster. */ +#define MALLOC_SEARCH_START _heapindex + +/* Data structure giving per-block information. */ +typedef union + { + /* Heap information for a busy block. */ + struct + { + /* Zero for a large block, or positive giving the + logarithm to the base two of the fragment size. */ + int type; + union + { + struct + { + size_t nfree; /* Free fragments in a fragmented block. */ + size_t first; /* First free fragment of the block. */ + } frag; + /* Size (in blocks) of a large cluster. */ + size_t size; + } info; + } busy; + /* Heap information for a free block (that may be the first of + a free cluster). */ + struct + { + size_t size; /* Size (in blocks) of a free cluster. */ + size_t next; /* Index of next free cluster. */ + size_t prev; /* Index of previous free cluster. */ + } free; + } malloc_info; + +/* Pointer to first block of the heap. */ +extern char *_heapbase; + +/* Table indexed by block number giving per-block information. */ +extern malloc_info *_heapinfo; + +/* Address to block number and vice versa. */ +#define BLOCK(A) (((char *) (A) - _heapbase) / BLOCKSIZE + 1) +#define ADDRESS(B) ((PTR) (((B) - 1) * BLOCKSIZE + _heapbase)) + +/* Current search index for the heap table. */ +extern size_t _heapindex; + +/* Limit of valid info table indices. */ +extern size_t _heaplimit; + +/* Doubly linked lists of free fragments. */ +struct list + { + struct list *next; + struct list *prev; + }; + +/* Free list headers for each fragment size. */ +extern struct list _fraghead[]; + +/* Instrumentation. */ +extern size_t _chunks_used; +extern size_t _bytes_used; +extern size_t _chunks_free; +extern size_t _bytes_free; + +/* Internal version of free() used in morecore(). */ +extern void EXFUN(__free, (PTR __ptr)); + +#endif /* _MALLOC_INTERNAL. */ + +/* Underlying allocation function; successive calls should + return contiguous pieces of memory. */ +extern PTR EXFUN((*__morecore), (ptrdiff_t __size)); + +/* Default value of previous. */ +extern PTR EXFUN(__default_morecore, (ptrdiff_t __size)); + +/* Flag whether malloc has been called. */ +extern int __malloc_initialized; + +/* Hooks for debugging versions. */ +extern void EXFUN((*__free_hook), (PTR __ptr)); +extern PTR EXFUN((*__malloc_hook), (size_t __size)); +extern PTR EXFUN((*__realloc_hook), (PTR __ptr, size_t __size)); + +/* Activate a standard collection of debugging hooks. */ +extern void EXFUN(mcheck, (void EXFUN((*func), (void)))); + +/* Statistics available to the user. */ +struct mstats + { + size_t bytes_total; /* Total size of the heap. */ + size_t chunks_used; /* Chunks allocated by the user. */ + size_t bytes_used; /* Byte total of user-allocated chunks. */ + size_t chunks_free; /* Chunks in the free list. */ + size_t bytes_free; /* Byte total of chunks in the free list. */ + }; + +/* Pick up the current statistics. */ +extern struct mstats EXFUN(mstats, (NOARGS)); + +#endif /* malloc.h */ + +/* DO NOT DELETE THIS LINE -- free.c INSERTED HERE. */ +/* Free a block of memory allocated by `malloc'. + Copyright 1990 Free Software Foundation + Written May 1989 by Mike Haertel. + + This program is free software; you can redistribute it and/or modify + it under the terms of the GNU General Public License as published by + the Free Software Foundation; either version 1, or (at your option) + any later version. + + This program is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + GNU General Public License for more details. + + You should have received a copy of the GNU General Public License + along with this program; if not, write to the Free Software + Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. + + The author may be reached (Email) at the address mike@ai.mit.edu, + or (US mail) as Mike Haertel c/o Free Software Foundation. */ + +#ifndef __ONEFILE +#include "ansidecl.h" +#include <stddef.h> +#include <stdlib.h> + +#define _MALLOC_INTERNAL +#include "malloc.h" +#endif /* __ONEFILE */ + +/* Debugging hook for free. */ +void EXFUN((*__free_hook), (PTR __ptr)); + +/* Return memory to the heap. Like free() but don't call a __free_hook + if there is one. */ +void +DEFUN(__free, (ptr), PTR ptr) +{ + int type; + size_t block, blocks; + register size_t i; + struct list *prev, *next; + + block = BLOCK(ptr); + + type = _heapinfo[block].busy.type; + switch (type) + { + case 0: + /* Get as many statistics as early as we can. */ + --_chunks_used; + _bytes_used -= _heapinfo[block].busy.info.size * BLOCKSIZE; + _bytes_free += _heapinfo[block].busy.info.size * BLOCKSIZE; + + /* Find the free cluster previous to this one in the free list. + Start searching at the last block referenced; this may benefit + programs with locality of allocation. */ + i = _heapindex; + if (i > block) + while (i > block) + i = _heapinfo[i].free.prev; + else + { + do + i = _heapinfo[i].free.next; + while (i > 0 && i < block); + i = _heapinfo[i].free.prev; + } + + /* Determine how to link this block into the free list. */ + if (block == i + _heapinfo[i].free.size) + { + /* Coalesce this block with its predecessor. */ + _heapinfo[i].free.size += _heapinfo[block].busy.info.size; + block = i; + } + else + { + /* Really link this block back into the free list. */ + _heapinfo[block].free.size = _heapinfo[block].busy.info.size; + _heapinfo[block].free.next = _heapinfo[i].free.next; + _heapinfo[block].free.prev = i; + _heapinfo[i].free.next = block; + _heapinfo[_heapinfo[block].free.next].free.prev = block; + ++_chunks_free; + } + + /* Now that the block is linked in, see if we can coalesce it + with its successor (by deleting its successor from the list + and adding in its size). */ + if (block + _heapinfo[block].free.size == _heapinfo[block].free.next) + { + _heapinfo[block].free.size + += _heapinfo[_heapinfo[block].free.next].free.size; + _heapinfo[block].free.next + = _heapinfo[_heapinfo[block].free.next].free.next; + _heapinfo[_heapinfo[block].free.next].free.prev = block; + --_chunks_free; + } + + /* Now see if we can return stuff to the system. */ + blocks = _heapinfo[block].free.size; + if (blocks >= FINAL_FREE_BLOCKS && block + blocks == _heaplimit + && (*__morecore)(0) == ADDRESS(block + blocks)) + { + register size_t bytes = blocks * BLOCKSIZE; + _heaplimit -= blocks; + (*__morecore)(- bytes); + _heapinfo[_heapinfo[block].free.prev].free.next + = _heapinfo[block].free.next; + _heapinfo[_heapinfo[block].free.next].free.prev + = _heapinfo[block].free.prev; + block = _heapinfo[block].free.prev; + --_chunks_free; + _bytes_free -= bytes; + } + + /* Set the next search to begin at this block. */ + _heapindex = block; + break; + + default: + /* Do some of the statistics. */ + --_chunks_used; + _bytes_used -= 1 << type; + ++_chunks_free; + _bytes_free += 1 << type; + + /* Get the address of the first free fragment in this block. */ + prev = (struct list *) ((char *) ADDRESS(block) + + (_heapinfo[block].busy.info.frag.first << type)); + + if (_heapinfo[block].busy.info.frag.nfree == (BLOCKSIZE >> type) - 1) + { + /* If all fragments of this block are free, remove them + from the fragment list and free the whole block. */ + next = prev; + for (i = 1; i < BLOCKSIZE >> type; ++i) + next = next->next; + prev->prev->next = next; + if (next != NULL) + next->prev = prev->prev; + _heapinfo[block].busy.type = 0; + _heapinfo[block].busy.info.size = 1; + + /* Keep the statistics accurate. */ + ++_chunks_used; + _bytes_used += BLOCKSIZE; + _chunks_free -= BLOCKSIZE >> type; + _bytes_free -= BLOCKSIZE; + + free(ADDRESS(block)); + } + else if (_heapinfo[block].busy.info.frag.nfree != 0) + { + /* If some fragments of this block are free, link this + fragment into the fragment list after the first free + fragment of this block. */ + next = (struct list *) ptr; + next->next = prev->next; + next->prev = prev; + prev->next = next; + if (next->next != NULL) + next->next->prev = next; + ++_heapinfo[block].busy.info.frag.nfree; + } + else + { + /* No fragments of this block are free, so link this + fragment into the fragment list and announce that + it is the first free fragment of this block. */ + prev = (struct list *) ptr; + _heapinfo[block].busy.info.frag.nfree = 1; + _heapinfo[block].busy.info.frag.first = (unsigned int) + (((char *) ptr - (char *) NULL) % BLOCKSIZE >> type); + prev->next = _fraghead[type].next; + prev->prev = &_fraghead[type]; + prev->prev->next = prev; + if (prev->next != NULL) + prev->next->prev = prev; + } + break; + } +} + +/* Return memory to the heap. */ +void +DEFUN(free, (ptr), PTR ptr) +{ + if (ptr == NULL) + return; + + if (__free_hook != NULL) + (*__free_hook)(ptr); + else + __free (ptr); +} + +/* DO NOT DELETE THIS LINE -- malloc.c INSERTED HERE. */ +/* Memory allocator `malloc'. + Copyright 1990 Free Software Foundation + Written May 1989 by Mike Haertel. + + This program is free software; you can redistribute it and/or modify + it under the terms of the GNU General Public License as published by + the Free Software Foundation; either version 1, or (at your option) + any later version. + + This program is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + GNU General Public License for more details. + + You should have received a copy of the GNU General Public License + along with this program; if not, write to the Free Software + Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. + + The author may be reached (Email) at the address mike@ai.mit.edu, + or (US mail) as Mike Haertel c/o Free Software Foundation. */ + +#ifndef __ONEFILE +#include "ansidecl.h" +#include <stddef.h> +#include <stdlib.h> +#include <string.h> + +#define _MALLOC_INTERNAL +#include "malloc.h" +#endif /* __ONEFILE */ + +/* How to really get more memory. */ +PTR EXFUN((*__morecore), (ptrdiff_t __size)) = __default_morecore; + +/* Debugging hook for `malloc'. */ +PTR EXFUN((*__malloc_hook), (size_t __size)); + +/* Pointer to the base of the first block. */ +char *_heapbase; + +/* Block information table. Allocated with align/__free (not malloc/free). */ +malloc_info *_heapinfo; + +/* Number of info entries. */ +static size_t heapsize; + +/* Search index in the info table. */ +size_t _heapindex; + +/* Limit of valid info table indices. */ +size_t _heaplimit; + +/* Free lists for each fragment size. */ +struct list _fraghead[BLOCKLOG]; + +/* Instrumentation. */ +size_t _chunks_used; +size_t _bytes_used; +size_t _chunks_free; +size_t _bytes_free; + +/* Are you experienced? */ +int __malloc_initialized; + +/* Aligned allocation. */ +static PTR +DEFUN(align, (size), size_t size) +{ + PTR result; + unsigned int adj; + + result = (*__morecore)(size); + adj = (unsigned int) ((char *) result - (char *) NULL) % BLOCKSIZE; + if (adj != 0) + { + adj = BLOCKSIZE - adj; + (void) (*__morecore)(adj); + result = (char *) result + adj; + } + return result; +} + +/* Set everything up and remember that we have. */ +static int +DEFUN_VOID(initialize) +{ + heapsize = HEAP / BLOCKSIZE; + _heapinfo = (malloc_info *) align(heapsize * sizeof(malloc_info)); + if (_heapinfo == NULL) + return 0; + memset(_heapinfo, 0, heapsize * sizeof(malloc_info)); + _heapinfo[0].free.size = 0; + _heapinfo[0].free.next = _heapinfo[0].free.prev = 0; + _heapindex = 0; + _heapbase = (char *) _heapinfo; + __malloc_initialized = 1; + return 1; +} + +/* Get neatly aligned memory, initializing or + growing the heap info table as necessary. */ +static PTR +DEFUN(morecore, (size), size_t size) +{ + PTR result; + malloc_info *newinfo, *oldinfo; + size_t newsize; + + result = align(size); + if (result == NULL) + return NULL; + + /* Check if we need to grow the info table. */ + if (BLOCK((char *) result + size) > heapsize) + { + newsize = heapsize; + while (BLOCK((char *) result + size) > newsize) + newsize *= 2; + newinfo = (malloc_info *) align(newsize * sizeof(malloc_info)); + if (newinfo == NULL) + { + (*__morecore)(- size); + return NULL; + } + memset(newinfo, 0, newsize * sizeof(malloc_info)); + memcpy(newinfo, _heapinfo, heapsize * sizeof(malloc_info)); + oldinfo = _heapinfo; + newinfo[BLOCK(oldinfo)].busy.type = 0; + newinfo[BLOCK(oldinfo)].busy.info.size + = BLOCKIFY(heapsize * sizeof(malloc_info)); + _heapinfo = newinfo; + __free(oldinfo); + heapsize = newsize; + } + + _heaplimit = BLOCK((char *) result + size); + return result; +} + +/* Allocate memory from the heap. */ +PTR +DEFUN(malloc, (size), size_t size) +{ + PTR result; + size_t block, blocks, lastblocks, start; + register size_t i; + struct list *next; + + if (size == 0) + return NULL; + + if (__malloc_hook != NULL) + return (*__malloc_hook)(size); + + if (!__malloc_initialized) + if (!initialize()) + return NULL; + + if (size < sizeof(struct list)) + size = sizeof(struct list); + + /* Determine the allocation policy based on the request size. */ + if (size <= BLOCKSIZE / 2) + { + /* Small allocation to receive a fragment of a block. + Determine the logarithm to base two of the fragment size. */ + register size_t log = 1; + --size; + while ((size /= 2) != 0) + ++log; + + /* Look in the fragment lists for a + free fragment of the desired size. */ + next = _fraghead[log].next; + if (next != NULL) + { + /* There are free fragments of this size. + Pop a fragment out of the fragment list and return it. + Update the block's nfree and first counters. */ + result = (PTR) next; + next->prev->next = next->next; + if (next->next != NULL) + next->next->prev = next->prev; + block = BLOCK(result); + if (--_heapinfo[block].busy.info.frag.nfree != 0) + _heapinfo[block].busy.info.frag.first = (unsigned int) + (((char *) next->next - (char *) NULL) % BLOCKSIZE) >> log; + + /* Update the statistics. */ + ++_chunks_used; + _bytes_used += 1 << log; + --_chunks_free; + _bytes_free -= 1 << log; + } + else + { + /* No free fragments of the desired size, so get a new block + and break it into fragments, returning the first. */ + result = malloc(BLOCKSIZE); + if (result == NULL) + return NULL; + + /* Link all fragments but the first into the free list. */ + for (i = 1; i < BLOCKSIZE >> log; ++i) + { + next = (struct list *) ((char *) result + (i << log)); + next->next = _fraghead[log].next; + next->prev = &_fraghead[log]; + next->prev->next = next; + if (next->next != NULL) + next->next->prev = next; + } + + /* Initialize the nfree and first counters for this block. */ + block = BLOCK(result); + _heapinfo[block].busy.type = log; + _heapinfo[block].busy.info.frag.nfree = i - 1; + _heapinfo[block].busy.info.frag.first = i - 1; + + _chunks_free += (BLOCKSIZE >> log) - 1; + _bytes_free += BLOCKSIZE - (1 << log); + } + } + else + { + /* Large allocation to receive one or more blocks. + Search the free list in a circle starting at the last place visited. + If we loop completely around without finding a large enough + space we will have to get more memory from the system. */ + blocks = BLOCKIFY(size); + start = block = MALLOC_SEARCH_START; + while (_heapinfo[block].free.size < blocks) + { + block = _heapinfo[block].free.next; + if (block == start) + { + /* Need to get more from the system. Check to see if + the new core will be contiguous with the final free + block; if so we don't need to get as much. */ + block = _heapinfo[0].free.prev; + lastblocks = _heapinfo[block].free.size; + if (_heaplimit != 0 && block + lastblocks == _heaplimit && + (*__morecore)(0) == ADDRESS(block + lastblocks) && + (morecore((blocks - lastblocks) * BLOCKSIZE)) != NULL) + { + _heapinfo[block].free.size = blocks; + _bytes_free += (blocks - lastblocks) * BLOCKSIZE; + continue; + } + result = morecore(blocks * BLOCKSIZE); + if (result == NULL) + return NULL; + block = BLOCK(result); + _heapinfo[block].busy.type = 0; + _heapinfo[block].busy.info.size = blocks; + ++_chunks_used; + _bytes_used += blocks * BLOCKSIZE; + return result; + } + } + + /* At this point we have found a suitable free list entry. + Figure out how to remove what we need from the list. */ + result = ADDRESS(block); + if (_heapinfo[block].free.size > blocks) + { + /* The block we found has a bit left over, + so relink the tail end back into the free list. */ + _heapinfo[block + blocks].free.size + = _heapinfo[block].free.size - blocks; + _heapinfo[block + blocks].free.next + = _heapinfo[block].free.next; + _heapinfo[block + blocks].free.prev + = _heapinfo[block].free.prev; + _heapinfo[_heapinfo[block].free.prev].free.next + = _heapinfo[_heapinfo[block].free.next].free.prev + = _heapindex = block + blocks; + } + else + { + /* The block exactly matches our requirements, + so just remove it from the list. */ + _heapinfo[_heapinfo[block].free.next].free.prev + = _heapinfo[block].free.prev; + _heapinfo[_heapinfo[block].free.prev].free.next + = _heapindex = _heapinfo[block].free.next; + --_chunks_free; + } + + _heapinfo[block].busy.type = 0; + _heapinfo[block].busy.info.size = blocks; + ++_chunks_used; + _bytes_used += blocks * BLOCKSIZE; + _bytes_free -= blocks * BLOCKSIZE; + } + + return result; +} + +/* DO NOT DELETE THIS LINE -- realloc.c INSERTED HERE. */ +/* Change the size of a block allocated by `malloc'. + Copyright 1990 Free Software Foundation + Written May 1989 by Mike Haertel. + + This program is free software; you can redistribute it and/or modify + it under the terms of the GNU General Public License as published by + the Free Software Foundation; either version 1, or (at your option) + any later version. + + This program is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + GNU General Public License for more details. + + You should have received a copy of the GNU General Public License + along with this program; if not, write to the Free Software + Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. + + The author may be reached (Email) at the address mike@ai.mit.edu, + or (US mail) as Mike Haertel c/o Free Software Foundation. */ + +#ifndef __ONEFILE +#include "ansidecl.h" +#include <stdlib.h> +#include <string.h> + +#define _MALLOC_INTERNAL +#include "malloc.h" +#endif /* __ONEFILE */ + +#define MIN(A, B) ((A) < (B) ? (A) : (B)) + +/* Debugging hook for realloc. */ +PTR EXFUN((*__realloc_hook), (PTR __ptr, size_t __size)); + +/* Resize the given region to the new size, returning a pointer + to the (possibly moved) region. This is optimized for speed; + some benchmarks seem to indicate that greater compactness is + achieved by unconditionally allocating and copying to a + new region. This module has incestuous knowledge of the + internals of both free and malloc. */ +PTR +DEFUN(realloc, (ptr, size), PTR ptr AND size_t size) +{ + PTR result; + int type; + size_t block, blocks, oldlimit; + + if (size == 0) + { + free(ptr); + return NULL; + } + else if (ptr == NULL) + return malloc(size); + + if (__realloc_hook != NULL) + return (*__realloc_hook)(ptr, size); + + block = BLOCK(ptr); + + type = _heapinfo[block].busy.type; + switch (type) + { + case 0: + /* Maybe reallocate a large block to a small fragment. */ + if (size <= BLOCKSIZE / 2) + { + result = malloc(size); + if (result != NULL) + { + memcpy(result, ptr, size); + free(ptr); + return result; + } + } + + /* The new size is a large allocation as well; + see if we can hold it in place. */ + blocks = BLOCKIFY(size); + if (blocks < _heapinfo[block].busy.info.size) + { + /* The new size is smaller; return + excess memory to the free list. */ + _heapinfo[block + blocks].busy.type = 0; + _heapinfo[block + blocks].busy.info.size + = _heapinfo[block].busy.info.size - blocks; + _heapinfo[block].busy.info.size = blocks; + free(ADDRESS(block + blocks)); + result = ptr; + } + else if (blocks == _heapinfo[block].busy.info.size) + /* No size change necessary. */ + result = ptr; + else + { + /* Won't fit, so allocate a new region that will. + Free the old region first in case there is sufficient + adjacent free space to grow without moving. */ + blocks = _heapinfo[block].busy.info.size; + /* Prevent free from actually returning memory to the system. */ + oldlimit = _heaplimit; + _heaplimit = 0; + free(ptr); + _heaplimit = oldlimit; + result = malloc(size); + if (result == NULL) + { + (void) malloc(blocks * BLOCKSIZE); + return NULL; + } + if (ptr != result) + memmove(result, ptr, blocks * BLOCKSIZE); + } + break; + + default: + /* Old size is a fragment; type is logarithm + to base two of the fragment size. */ + if (size > 1 << (type - 1) && size <= 1 << type) + /* The new size is the same kind of fragment. */ + result = ptr; + else + { + /* The new size is different; allocate a new space, + and copy the lesser of the new size and the old. */ + result = malloc(size); + if (result == NULL) + return NULL; + memcpy(result, ptr, MIN(size, 1 << type)); + free(ptr); + } + break; + } + + return result; +} + +/* DO NOT DELETE THIS LINE -- unix.c INSERTED HERE. */ +/* unix.c - get more memory with a UNIX system call. + Copyright 1990 Free Software Foundation + Written May 1989 by Mike Haertel. + + This program is free software; you can redistribute it and/or modify + it under the terms of the GNU General Public License as published by + the Free Software Foundation; either version 1, or (at your option) + any later version. + + This program is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + GNU General Public License for more details. + + You should have received a copy of the GNU General Public License + along with this program; if not, write to the Free Software + Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. + + The author may be reached (Email) at the address mike@ai.mit.edu, + or (US mail) as Mike Haertel c/o Free Software Foundation. */ + +#ifndef __ONEFILE +#include "ansidecl.h" +#include <stddef.h> + +#define _MALLOC_INTERNAL +#include "malloc.h" +#endif /* __ONEFILE */ + +extern PTR EXFUN(sbrk, (ptrdiff_t size)); + +PTR +DEFUN(__default_morecore, (size), ptrdiff_t size) +{ + PTR result; + + result = sbrk(size); + if (result == (PTR) -1) + return NULL; + return result; +} + +#define __getpagesize getpagesize +/* DO NOT DELETE THIS LINE -- valloc.c INSERTED HERE. */ +/* Allocate memory on a page boundary. + Copyright 1990 Free Software Foundation + Written May 1989 by Mike Haertel. + + This program is free software; you can redistribute it and/or modify + it under the terms of the GNU General Public License as published by + the Free Software Foundation; either version 1, or (at your option) + any later version. + + This program is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + GNU General Public License for more details. + + You should have received a copy of the GNU General Public License + along with this program; if not, write to the Free Software + Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. + + The author may be reached (Email) at the address mike@ai.mit.edu, + or (US mail) as Mike Haertel c/o Free Software Foundation. */ + +#ifndef __ONEFILE +#include "ansidecl.h" +#include <stdlib.h> +#endif /* __ONEFILE */ + +extern size_t EXFUN(__getpagesize, (NOARGS)); + +static size_t pagesize; + +PTR +DEFUN(valloc, (size), size_t size) +{ + PTR result; + unsigned int adj; + + if (pagesize == 0) + pagesize = __getpagesize(); + + result = malloc(size + pagesize); + if (result == NULL) + return NULL; + adj = (unsigned int) ((char *) result - (char *) NULL) % pagesize; + if (adj != 0) + result = (char *) result + pagesize - adj; + return result; +} |