diff options
Diffstat (limited to 'malloc')
| -rw-r--r-- | malloc/malloc.c | 69 |
1 files changed, 44 insertions, 25 deletions
diff --git a/malloc/malloc.c b/malloc/malloc.c index 4bdc2585cb..43d89d43da 100644 --- a/malloc/malloc.c +++ b/malloc/malloc.c @@ -182,10 +182,11 @@ MALLOC_HOOKS (default: NOT defined) Define to enable support run-time replacement of the allocation functions through user-defined `hooks'. - REALLOC_ZERO_BYTES_FREES (default: NOT defined) + REALLOC_ZERO_BYTES_FREES (default: 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). + to free(p). (The C standard requires this behaviour, therefore + it is the default.) 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. @@ -366,10 +367,10 @@ extern "C" { #endif /* - 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). + REALLOC_ZERO_BYTES_FREES should be set if a call to realloc with + zero bytes should be the same as a call to free. The C standard + requires this. Otherwise, since this malloc returns a unique pointer + for malloc(0), so does realloc(p, 0). */ @@ -528,6 +529,9 @@ do { \ #if !defined(MAP_ANONYMOUS) && defined(MAP_ANON) #define MAP_ANONYMOUS MAP_ANON #endif +#if !defined(MAP_FAILED) +#define MAP_FAILED ((char*)-1) +#endif #ifndef MAP_NORESERVE # ifdef MAP_AUTORESRV @@ -818,6 +822,15 @@ do { \ computed. */ + +/* On some platforms we can compile internal, not exported functions better. + Let the environment provide a macro and define it to be empty if it + is not available. */ +#ifndef internal_function +# define internal_function +#endif + + /* Special defines for the Linux/GNU C library. @@ -1230,13 +1243,6 @@ static void free_atfork(); #endif -/* On some platforms we can compile internal, not exported functions better. - Let the environment provide a macro and define it to be empty if it - is not available. */ -#ifndef internal_function -# define internal_function -#endif - /* sizes, alignments */ @@ -1613,7 +1619,7 @@ ptmalloc_init_all __MALLOC_P((void)) (void)mutex_init(&list_lock); } -#endif +#endif /* !defined NO_THREADS */ /* Initialization routine. */ #if defined(_LIBC) @@ -1852,10 +1858,12 @@ mmap_chunk(size) size_t size; return p; } +static void +internal_function #if __STD_C -static void munmap_chunk(mchunkptr p) +munmap_chunk(mchunkptr p) #else -static void munmap_chunk(p) mchunkptr p; +munmap_chunk(p) mchunkptr p; #endif { INTERNAL_SIZE_T size = chunksize(p); @@ -1877,10 +1885,12 @@ static void munmap_chunk(p) mchunkptr p; #if HAVE_MREMAP +static mchunkptr +internal_function #if __STD_C -static mchunkptr mremap_chunk(mchunkptr p, size_t new_size) +mremap_chunk(mchunkptr p, size_t new_size) #else -static mchunkptr mremap_chunk(p, new_size) mchunkptr p; size_t new_size; +mremap_chunk(p, new_size) mchunkptr p; size_t new_size; #endif { size_t page_mask = malloc_getpagesize - 1; @@ -1899,7 +1909,7 @@ static mchunkptr mremap_chunk(p, new_size) mchunkptr p; size_t new_size; cp = (char *)mremap((char *)p - offset, size + offset, new_size, MREMAP_MAYMOVE); - if (cp == (char *)-1) return 0; + if (cp == MAP_FAILED) return 0; p = (mchunkptr)(cp + offset); @@ -3034,7 +3044,7 @@ chunk_free(ar_ptr, p) arena *ar_ptr; mchunkptr p; if(next->size < MINSIZE && (unsigned long)sz > trim_threshold && ar_ptr != &main_arena) { /* fencepost */ - heap_info* heap = heap_for_ptr(top(ar_ptr)); + heap_info *heap = heap_for_ptr(top(ar_ptr)); if(top(ar_ptr) == chunk_at_offset(heap, sizeof(*heap)) && heap->prev == heap_for_ptr(p)) @@ -4212,6 +4222,7 @@ mALLOC_SET_STATe(msptr) Void_t* msptr; into a user pointer with requested size sz. */ static Void_t* +internal_function #if __STD_C chunk2mem_check(mchunkptr p, size_t sz) #else @@ -4293,6 +4304,7 @@ mem2chunk_check(mem) Void_t* mem; necessary. */ static int +internal_function #if __STD_C top_check(void) #else @@ -4525,11 +4537,18 @@ malloc_atfork(sz, caller) size_t sz; const Void_t *caller; #endif { Void_t *vptr = NULL; + mchunkptr victim; tsd_getspecific(arena_key, vptr); if(!vptr) { - mchunkptr victim = chunk_alloc(&main_arena, request2size(sz)); - return victim ? chunk2mem(victim) : 0; + if(save_malloc_hook != malloc_check) { + victim = chunk_alloc(&main_arena, request2size(sz)); + return victim ? chunk2mem(victim) : 0; + } else { + if(top_check() < 0) return 0; + victim = chunk_alloc(&main_arena, request2size(sz+1)); + return victim ? chunk2mem_check(victim, sz) : 0; + } } else { /* Suspend the thread until the `atfork' handlers have completed. By that time, the hooks will have been reset as well, so that @@ -4554,7 +4573,7 @@ free_atfork(mem, caller) Void_t* mem; const Void_t *caller; if (mem == 0) /* free(0) has no effect */ return; - p = mem2chunk(mem); + p = mem2chunk(mem); /* do not bother to replicate free_check here */ #if HAVE_MMAP if (chunk_is_mmapped(p)) /* release mmapped memory. */ @@ -4573,7 +4592,7 @@ free_atfork(mem, caller) Void_t* mem; const Void_t *caller; (void)mutex_unlock(&ar_ptr->mutex); } -#endif +#endif /* !defined NO_THREADS */ #endif /* defined _LIBC || defined MALLOC_HOOKS */ |