コード例 #1
0
static Void_t*
malloc_atfork(size_t sz, const Void_t *caller)
{
  Void_t *vptr = NULL;
  Void_t *victim;

  tsd_getspecific(arena_key, vptr);
  if(vptr == ATFORK_ARENA_PTR) {
    /* We are the only thread that may allocate at all.  */
    if(save_malloc_hook != malloc_check) {
      return _int_malloc(&main_arena, sz);
    } else {
      if(top_check()<0)
        return 0;
      victim = _int_malloc(&main_arena, sz+1);
      return mem2mem_check(victim, sz);
    }
  } else {
    /* Suspend the thread until the `atfork' handlers have completed.
       By that time, the hooks will have been reset as well, so that
       mALLOc() can be used again. */
    (void)mutex_lock(&list_lock);
    (void)mutex_unlock(&list_lock);
    return public_mALLOc(sz);
  }
}
コード例 #2
0
ファイル: hooks.c プロジェクト: AdvancedC/glibc
static void*
malloc_check(size_t sz, const void *caller)
{
  void *victim;

  if (sz+1 == 0) {
    __set_errno (ENOMEM);
    return NULL;
  }

  (void)mutex_lock(&main_arena.mutex);
  victim = (top_check() >= 0) ? _int_malloc(&main_arena, sz+1) : NULL;
  (void)mutex_unlock(&main_arena.mutex);
  return mem2mem_check(victim, sz);
}
コード例 #3
0
ファイル: hooks.c プロジェクト: AdvancedC/glibc
static void*
realloc_check(void* oldmem, size_t bytes, const void *caller)
{
  INTERNAL_SIZE_T nb;
  void* newmem = 0;
  unsigned char *magic_p;

  if (bytes+1 == 0) {
    __set_errno (ENOMEM);
    return NULL;
  }
  if (oldmem == 0) return malloc_check(bytes, NULL);
  if (bytes == 0) {
    free_check (oldmem, NULL);
    return NULL;
  }
  (void)mutex_lock(&main_arena.mutex);
  const mchunkptr oldp = mem2chunk_check(oldmem, &magic_p);
  (void)mutex_unlock(&main_arena.mutex);
  if(!oldp) {
    malloc_printerr(check_action, "realloc(): invalid pointer", oldmem);
    return malloc_check(bytes, NULL);
  }
  const INTERNAL_SIZE_T oldsize = chunksize(oldp);

  checked_request2size(bytes+1, nb);
  (void)mutex_lock(&main_arena.mutex);

  if (chunk_is_mmapped(oldp)) {
#if HAVE_MREMAP
    mchunkptr newp = mremap_chunk(oldp, nb);
    if(newp)
      newmem = chunk2mem(newp);
    else
#endif
    {
      /* Note the extra SIZE_SZ overhead. */
      if(oldsize - SIZE_SZ >= nb)
	newmem = oldmem; /* do nothing */
      else {
	/* Must alloc, copy, free. */
	if (top_check() >= 0)
	  newmem = _int_malloc(&main_arena, bytes+1);
	if (newmem) {
	  MALLOC_COPY(newmem, oldmem, oldsize - 2*SIZE_SZ);
	  munmap_chunk(oldp);
	}
      }
    }
  } else {
    if (top_check() >= 0) {
      INTERNAL_SIZE_T nb;
      checked_request2size(bytes + 1, nb);
      newmem = _int_realloc(&main_arena, oldp, oldsize, nb);
    }
  }

  /* mem2chunk_check changed the magic byte in the old chunk.
     If newmem is NULL, then the old chunk will still be used though,
     so we need to invert that change here.  */
  if (newmem == NULL) *magic_p ^= 0xFF;

  (void)mutex_unlock(&main_arena.mutex);

  return mem2mem_check(newmem, bytes);
}