diff options
Diffstat (limited to 'winsup/cygwin/dlmalloc.c')
| -rw-r--r-- | winsup/cygwin/dlmalloc.c | 439 |
1 files changed, 229 insertions, 210 deletions
diff --git a/winsup/cygwin/dlmalloc.c b/winsup/cygwin/dlmalloc.c index 809728c..3435950 100644 --- a/winsup/cygwin/dlmalloc.c +++ b/winsup/cygwin/dlmalloc.c @@ -28,6 +28,25 @@ * malloc_usable_size(P) is equivalent to realloc(P, malloc_usable_size(P)) * * $Log$ + * Revision 1.4 2001/09/07 21:32:04 cgf + * * cygheap.h (init_cygheap): Move heap pointers here. + * * include/sys/cygwin.h (perprocess): Remove heap pointers. + * * dcrt0.cc (__cygwin_user_data): Reflect obsolete perprocess stuff. + * (_dll_crt0): Don't initialize heap pointers. + * (cygwin_dll_init): Ditto. + * (release_upto): Use heap pointers from cygheap. + * * heap.h: Ditto. + * * fork.cc (fork_parent): Ditto. Don't set heap pointers in ch. + * (fork_child): Remove obsolete sigproc_fixup_after_fork. + * * shared.cc (memory_init): Reorganize so that cygheap initialization is called + * prior to regular heap since regular heap uses cygheap now. + * * sigproc.cc (proc_subproc): Eliminate zombies allocation. + * (sigproc_init): Move zombies alloation here. Don't free up array on fork, just + * reuse it. + * (sigproc_fixup_after_fork): Eliminate. + * * sigproc.h: Ditto. + * * include/cygwin/version.h: Reflect change to perprocess structure. + * * Revision 1.3 2001/06/26 14:47:48 cgf * * mmap.cc: Clean up *ResourceLock calls throughout. * * thread.cc (pthread_cond::TimedWait): Check for WAIT_TIMEOUT as well as @@ -64,8 +83,8 @@ * VERSION 2.6.4 Thu Nov 28 07:54:55 1996 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! + ftp://g.oswego.edu/pub/misc/malloc.c + Check before installing! * Why use this malloc? @@ -142,7 +161,7 @@ and status information. Minimum allocated size: 4-byte ptrs: 16 bytes (including 4 overhead) - 8-byte ptrs: 24/32 bytes (including, 4/8 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 @@ -154,7 +173,7 @@ 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 + 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 @@ -170,11 +189,11 @@ 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. + 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 @@ -435,14 +454,14 @@ do { \ if(mzsz <= 9*sizeof(mzsz)) { \ INTERNAL_SIZE_T* mz = (INTERNAL_SIZE_T*) (charp); \ if(mzsz >= 5*sizeof(mzsz)) { *mz++ = 0; \ - *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; \ + *mz++ = 0; \ + if(mzsz >= 9*sizeof(mzsz)) { *mz++ = 0; \ + *mz++ = 0; }}} \ + *mz++ = 0; \ + *mz++ = 0; \ + *mz = 0; \ } else memset((charp), 0, mzsz); \ } while(0) @@ -453,14 +472,14 @@ do { \ 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++; \ + *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 ; \ + *mcdst++ = *mcsrc++; \ + if(mcsz >= 9*sizeof(mcsz)) { *mcdst++ = *mcsrc++; \ + *mcdst++ = *mcsrc++; }}} \ + *mcdst++ = *mcsrc++; \ + *mcdst++ = *mcsrc++; \ + *mcdst = *mcsrc ; \ } else memcpy(dest, src, mcsz); \ } while(0) @@ -588,9 +607,9 @@ do { \ # else # if defined(BSD) || defined(DGUX) || defined(HAVE_GETPAGESIZE) # if __STD_C - extern size_t getpagesize(void); + extern size_t getpagesize(void); # else - extern size_t getpagesize(); + extern size_t getpagesize(); # endif # define malloc_getpagesize getpagesize() # else @@ -751,11 +770,11 @@ struct mallinfo { 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. + 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. + 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. @@ -801,15 +820,15 @@ struct mallinfo { 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. + 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. @@ -831,15 +850,15 @@ struct mallinfo { 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. + 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 @@ -1162,7 +1181,7 @@ void gcleanup () rval = VirtualFree ((void*)gAddressBase, gNextAddress - gAddressBase, MEM_DECOMMIT); - ASSERT (rval); + ASSERT (rval); } while (head) { @@ -1326,17 +1345,17 @@ typedef Chunk* mchunkptr; chunk-> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ - | Size of previous chunk, if allocated | | - +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ - | Size of chunk, in bytes |P| + | Size of previous chunk, if allocated | | + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + | Size of chunk, in bytes |P| mem-> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ - | User data starts here... . - . . - . (malloc_usable_space() bytes) . - . | + | User data starts here... . + . . + . (malloc_usable_space() bytes) . + . | nextchunk-> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ - | Size of chunk | - +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + | Size of chunk | + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Where "chunk" is the front of the chunk for the purpose of most of @@ -1350,20 +1369,20 @@ nextchunk-> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Free chunks are stored in circular doubly-linked lists, and look like this: chunk-> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ - | Size of previous 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) . - . . - . | + | 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 @@ -1380,16 +1399,16 @@ nextchunk-> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 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.) + 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. + 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): @@ -1682,7 +1701,7 @@ static mbinptr av_[NAV * 2 + 2] = { ((((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) + 126) /* bins for chunks < 512 are all spaced 8 bytes apart, and hold identically sized chunks. This is exploited in malloc. @@ -2565,20 +2584,20 @@ static void malloc_extend_top(nb) INTERNAL_SIZE_T nb; /* 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; + set_head(top, PREV_INUSE); /* will force null return from malloc */ + return; } old_top_size -= 2*SIZE_SZ; chunk_at_offset(old_top, old_top_size )->size = - SIZE_SZ|PREV_INUSE; + SIZE_SZ|PREV_INUSE; chunk_at_offset(old_top, old_top_size + SIZE_SZ)->size = - SIZE_SZ|PREV_INUSE; + SIZE_SZ|PREV_INUSE; set_head_size(old_top, old_top_size); /* If possible, release the rest. */ if (old_top_size >= MINSIZE) { init_freeable_chunk(old_top); - fREe(chunk2mem(old_top)); + fREe(chunk2mem(old_top)); } } #endif /* OTHER_SBRKS */ @@ -2613,43 +2632,43 @@ static void malloc_extend_top(nb) INTERNAL_SIZE_T nb; 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. + 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. + 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. + 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). + (`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. + 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. + 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 @@ -2725,18 +2744,18 @@ Void_t* mALLOc(bytes) size_t bytes; if (remainder_size >= (long)MINSIZE) /* too big */ { - --idx; /* adjust to rescan below after checking last remainder */ - break; + --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); + unlink(victim, bck, fwd); + set_inuse_bit_at_offset(victim, victim_size); check_freefill(victim, victim_size, victim_size); init_malloced_chunk(victim, bytes); check_malloced_chunk(victim, nb); - return chunk2mem(victim); + return chunk2mem(victim); } } @@ -2798,8 +2817,8 @@ Void_t* mALLOc(bytes) size_t bytes; block <<= 1; while ((block & binblocks) == 0) { - idx += BINBLOCKWIDTH; - block <<= 1; + idx += BINBLOCKWIDTH; + block <<= 1; } } @@ -2812,39 +2831,39 @@ Void_t* mALLOc(bytes) size_t bytes; /* For each bin in this block ... */ do { - /* Find and use first big enough chunk ... */ + /* Find and use first big enough chunk ... */ - for (victim = last(bin); victim != bin; victim = victim->bk) - { - victim_size = chunksize(victim); - remainder_size = victim_size - nb; + for (victim = last(bin); victim != bin; victim = victim->bk) + { + victim_size = chunksize(victim); + remainder_size = victim_size - nb; - if (remainder_size >= (long)MINSIZE) /* split */ - { - remainder = chunk_at_offset(victim, nb); - set_head(victim, nb | PREV_INUSE); + if (remainder_size >= (long)MINSIZE) /* split */ + { + remainder = chunk_at_offset(victim, nb); + set_head(victim, nb | PREV_INUSE); check_freefill(victim, nb, victim_size); - unlink(victim, bck, fwd); - init_malloced_chunk(victim, bytes); + unlink(victim, bck, fwd); + init_malloced_chunk(victim, bytes); link_last_remainder(remainder); - set_head(remainder, remainder_size | PREV_INUSE); - set_foot(remainder, remainder_size); + set_head(remainder, remainder_size | PREV_INUSE); + set_foot(remainder, remainder_size); init_freed_chunk(remainder, remainder_size, 0); check_malloced_chunk(victim, nb); - return chunk2mem(victim); - } + return chunk2mem(victim); + } - else if (remainder_size >= 0) /* take */ - { + else if (remainder_size >= 0) /* take */ + { check_freefill(victim, victim_size, victim_size); - set_inuse_bit_at_offset(victim, victim_size); - unlink(victim, bck, fwd); + set_inuse_bit_at_offset(victim, victim_size); + unlink(victim, bck, fwd); init_malloced_chunk(victim, bytes); check_malloced_chunk(victim, nb); - return chunk2mem(victim); - } + return chunk2mem(victim); + } - } + } bin = next_bin(bin); @@ -2854,12 +2873,12 @@ Void_t* mALLOc(bytes) size_t bytes; do /* Possibly backtrack to try to clear a partial block */ { - if ((startidx & (BINBLOCKWIDTH - 1)) == 0) - { - binblocks &= ~block; - break; - } - --startidx; + if ((startidx & (BINBLOCKWIDTH - 1)) == 0) + { + binblocks &= ~block; + break; + } + --startidx; q = prev_bin(q); } while (first(q) == q); @@ -2867,14 +2886,14 @@ Void_t* mALLOc(bytes) size_t bytes; if ( (block <<= 1) <= binblocks && (block != 0) ) { - while ((block & binblocks) == 0) - { - idx += BINBLOCKWIDTH; - block <<= 1; - } + while ((block & binblocks) == 0) + { + idx += BINBLOCKWIDTH; + block <<= 1; + } } else - break; + break; } } @@ -2888,7 +2907,7 @@ Void_t* mALLOc(bytes) size_t bytes; #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) { + (victim = mmap_chunk(nb)) != 0) { init_malloced_chunk(victim, bytes); return chunk2mem(victim); } @@ -2926,13 +2945,13 @@ Void_t* mALLOc(bytes) size_t bytes; 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. + 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'). + placed in corresponding bins. (This includes the case of + consolidating with the current `last_remainder'). */ @@ -3152,26 +3171,26 @@ Void_t* rEALLOc(oldmem, bytes) Void_t* oldmem; size_t bytes; /* Forward into top only if a remainder */ if (next == top) { - if ((long)(nextsize + newsize) >= (long)(nb + MINSIZE)) - { + if ((long)(nextsize + newsize) >= (long)(nb + MINSIZE)) + { check_freefill(next, nb - oldsize, nextsize); newsize += nextsize; - top = chunk_at_offset(oldp, nb); - set_head(top, (newsize - nb) | PREV_INUSE); + top = chunk_at_offset(oldp, nb); + set_head(top, (newsize - nb) | PREV_INUSE); init_freed_chunk(top, newsize - nb, 0); - set_head_size(oldp, nb); + set_head_size(oldp, nb); init_realloced_chunk(oldp, bytes, oldsize); return chunk2mem(oldp); - } + } } /* Forward into next chunk */ else if (((long)(nextsize + newsize) >= (long)nb)) { check_freefill(next, nb - oldsize, nextsize); - unlink(next, bck, fwd); - newsize += nextsize; - goto split; + unlink(next, bck, fwd); + newsize += nextsize; + goto split; } } else @@ -3191,52 +3210,52 @@ Void_t* rEALLOc(oldmem, bytes) Void_t* oldmem; size_t bytes; if (next != 0) { - /* into top */ - if (next == top) - { - if ((long)(nextsize + prevsize + newsize) >= (long)(nb + MINSIZE)) - { + /* into top */ + if (next == top) + { + if ((long)(nextsize + prevsize + newsize) >= (long)(nb + MINSIZE)) + { check_freefill(prev, nb, prevsize); check_freefill(next, nb - (prevsize + newsize), nextsize); unlink(prev, bck, fwd); - newp = prev; - newsize += prevsize + nextsize; - newmem = chunk2mem(newp); - malloc_COPY(newmem, oldmem, oldsize - OVERHEAD); - top = chunk_at_offset(newp, nb); - set_head(top, (newsize - nb) | PREV_INUSE); + newp = prev; + newsize += prevsize + nextsize; + newmem = chunk2mem(newp); + malloc_COPY(newmem, oldmem, oldsize - OVERHEAD); + top = chunk_at_offset(newp, nb); + set_head(top, (newsize - nb) | PREV_INUSE); init_freed_chunk(top, newsize - nb, 0); - set_head_size(newp, nb); + set_head_size(newp, nb); init_realloced_chunk(newp, bytes, oldsize); - return newmem; - } - } + return newmem; + } + } - /* into next chunk */ - else if (((long)(nextsize + prevsize + newsize) >= (long)(nb))) - { + /* into next chunk */ + else if (((long)(nextsize + prevsize + newsize) >= (long)(nb))) + { check_freefill(prev, nb, prevsize); check_freefill(next, nb - (prevsize + newsize), nextsize); - unlink(next, bck, fwd); - unlink(prev, bck, fwd); - newp = prev; - newsize += nextsize + prevsize; - newmem = chunk2mem(newp); - malloc_COPY(newmem, oldmem, oldsize - OVERHEAD); - goto split; - } + unlink(next, bck, fwd); + unlink(prev, bck, fwd); + newp = prev; + newsize += nextsize + prevsize; + newmem = chunk2mem(newp); + malloc_COPY(newmem, oldmem, oldsize - OVERHEAD); + goto split; + } } /* backward only */ if (prev != 0 && (long)(prevsize + newsize) >= (long)nb) { check_freefill(prev, nb, prevsize); - unlink(prev, bck, fwd); - newp = prev; - newsize += prevsize; - newmem = chunk2mem(newp); - malloc_COPY(newmem, oldmem, oldsize - OVERHEAD); - goto split; + unlink(prev, bck, fwd); + newp = prev; + newsize += prevsize; + newmem = chunk2mem(newp); + malloc_COPY(newmem, oldmem, oldsize - OVERHEAD); + goto split; } } @@ -3572,27 +3591,27 @@ int malloc_trim(pad) size_t pad; if (new_lim == (char*)(MORECORE_FAILURE)) /* sbrk failed? */ { - /* Try to figure out what we have */ - current_lim = (char*)(MORECORE (0)); - top_size = current_lim - (char*)top; - if (top_size >= (long)MINSIZE) /* if not, we are very very dead! */ - { - sbrked_mem = current_lim - sbrk_base; - set_head(top, top_size | PREV_INUSE); + /* Try to figure out what we have */ + current_lim = (char*)(MORECORE (0)); + top_size = current_lim - (char*)top; + if (top_size >= (long)MINSIZE) /* if not, we are very very dead! */ + { + sbrked_mem = current_lim - sbrk_base; + set_head(top, top_size | PREV_INUSE); init_freed_chunk(top, top_size, 0); - } - check_chunk(top); - return 0; + } + check_chunk(top); + return 0; } else { - /* Success. Adjust top accordingly. */ - set_head(top, (top_size - extra) | PREV_INUSE); - sbrked_mem -= extra; + /* Success. Adjust top accordingly. */ + set_head(top, (top_size - extra) | PREV_INUSE); + sbrked_mem -= extra; init_freed_chunk(top, top_size - extra, 0); - check_chunk(top); - return 1; + check_chunk(top); + return 1; } } } |