void __zbx_mem_free(const char *file, int line, zbx_mem_info_t *info, void *ptr) { const char *__function_name = "zbx_mem_free"; if (NULL == ptr) { zabbix_log(LOG_LEVEL_CRIT, "[file:%s,line:%d] %s(): freeing a NULL pointer", file, line, __function_name); exit(FAIL); } LOCK_INFO; __mem_free(info, ptr); UNLOCK_INFO; }
static void *__mem_realloc(zbx_mem_info_t *info, void *old, zbx_uint64_t size) { void *chunk, *new_chunk, *next_chunk; zbx_uint64_t chunk_size, new_chunk_size; int next_free; size = mem_proper_alloc_size(size); chunk = old - MEM_SIZE_FIELD; chunk_size = CHUNK_SIZE(chunk); next_chunk = chunk + MEM_SIZE_FIELD + chunk_size + MEM_SIZE_FIELD; next_free = (next_chunk < info->hi_bound && FREE_CHUNK(next_chunk)); if (size <= chunk_size) { /* do not reallocate if not much is freed */ /* we are likely to want more memory again */ if (size > chunk_size / 4) return chunk; if (next_free) { /* merge with next chunk */ info->used_size -= chunk_size; info->used_size += size; info->free_size += chunk_size + 2 * MEM_SIZE_FIELD; info->free_size -= size + 2 * MEM_SIZE_FIELD; new_chunk = chunk + MEM_SIZE_FIELD + size + MEM_SIZE_FIELD; new_chunk_size = CHUNK_SIZE(next_chunk) + (chunk_size - size); mem_unlink_chunk(info, next_chunk); mem_set_chunk_size(new_chunk, new_chunk_size); mem_link_chunk(info, new_chunk); mem_set_used_chunk_size(chunk, size); } else { /* split the current one */ info->used_size -= chunk_size; info->used_size += size; info->free_size += chunk_size; info->free_size -= size + 2 * MEM_SIZE_FIELD; new_chunk = chunk + MEM_SIZE_FIELD + size + MEM_SIZE_FIELD; new_chunk_size = chunk_size - size - 2 * MEM_SIZE_FIELD; mem_set_chunk_size(new_chunk, new_chunk_size); mem_link_chunk(info, new_chunk); mem_set_used_chunk_size(chunk, size); } return chunk; } if (next_free && chunk_size + 2 * MEM_SIZE_FIELD + CHUNK_SIZE(next_chunk) >= size) { info->used_size -= chunk_size; info->free_size += chunk_size; chunk_size += 2 * MEM_SIZE_FIELD + CHUNK_SIZE(next_chunk); mem_unlink_chunk(info, next_chunk); /* either use the full next_chunk or split it */ if (chunk_size < size + 2 * MEM_SIZE_FIELD + MEM_MIN_ALLOC) { info->used_size += chunk_size; info->free_size -= chunk_size; mem_set_used_chunk_size(chunk, chunk_size); } else { new_chunk = chunk + MEM_SIZE_FIELD + size + MEM_SIZE_FIELD; new_chunk_size = chunk_size - size - 2 * MEM_SIZE_FIELD; mem_set_chunk_size(new_chunk, new_chunk_size); mem_link_chunk(info, new_chunk); info->used_size += size; info->free_size -= chunk_size; info->free_size += new_chunk_size; mem_set_used_chunk_size(chunk, size); } return chunk; } else if (NULL != (new_chunk = __mem_malloc(info, size))) { memcpy(new_chunk + MEM_SIZE_FIELD, chunk + MEM_SIZE_FIELD, chunk_size); __mem_free(info, old); return new_chunk; } else { void *tmp = NULL; tmp = zbx_malloc(tmp, chunk_size); memcpy(tmp, chunk + MEM_SIZE_FIELD, chunk_size); __mem_free(info, old); new_chunk = __mem_malloc(info, size); if (NULL != new_chunk) { memcpy(new_chunk + MEM_SIZE_FIELD, tmp, chunk_size); } else { int index; void *last_chunk; index = mem_bucket_by_size(chunk_size); last_chunk = info->buckets[index]; mem_unlink_chunk(info, last_chunk); if (chunk != last_chunk) { /* The chunk was merged with a free space on the left during */ /* __mem_free() operation. The left chunk must be restored to */ /* its previous state to avoid memory leaks. */ /* We can safely ignore if the chunk was merged on the right */ /* as it will just increase the size of allocated chunk. */ zbx_uint64_t left_size; left_size = chunk - last_chunk - 2 * MEM_SIZE_FIELD; mem_set_chunk_size(chunk, CHUNK_SIZE(chunk) - left_size - 2 * MEM_SIZE_FIELD); mem_set_chunk_size(last_chunk, left_size); mem_link_chunk(info, last_chunk); } memcpy(chunk + MEM_SIZE_FIELD, tmp, chunk_size); } zbx_free(tmp); return new_chunk; } }
static void *__mem_realloc(zbx_mem_info_t *info, void *old, zbx_uint64_t size) { void *chunk, *new_chunk, *next_chunk; zbx_uint64_t chunk_size, new_chunk_size; int next_free; size = mem_proper_alloc_size(size); chunk = (void *)((char *)old - MEM_SIZE_FIELD); chunk_size = CHUNK_SIZE(chunk); next_chunk = (void *)((char *)chunk + MEM_SIZE_FIELD + chunk_size + MEM_SIZE_FIELD); next_free = (next_chunk < info->hi_bound && FREE_CHUNK(next_chunk)); if (size <= chunk_size) { /* do not reallocate if not much is freed */ /* we are likely to want more memory again */ if (size > chunk_size / 4) return chunk; if (next_free) { /* merge with next chunk */ info->used_size -= chunk_size - size; info->free_size += chunk_size - size; new_chunk = (void *)((char *)chunk + MEM_SIZE_FIELD + size + MEM_SIZE_FIELD); new_chunk_size = CHUNK_SIZE(next_chunk) + (chunk_size - size); mem_unlink_chunk(info, next_chunk); mem_set_chunk_size(new_chunk, new_chunk_size); mem_link_chunk(info, new_chunk); mem_set_used_chunk_size(chunk, size); } else { /* split the current one */ info->used_size -= chunk_size - size; info->free_size += chunk_size - size - 2 * MEM_SIZE_FIELD; new_chunk = (void *)((char *)chunk + MEM_SIZE_FIELD + size + MEM_SIZE_FIELD); new_chunk_size = chunk_size - size - 2 * MEM_SIZE_FIELD; mem_set_chunk_size(new_chunk, new_chunk_size); mem_link_chunk(info, new_chunk); mem_set_used_chunk_size(chunk, size); } return chunk; } if (next_free && chunk_size + 2 * MEM_SIZE_FIELD + CHUNK_SIZE(next_chunk) >= size) { info->used_size -= chunk_size; info->free_size += chunk_size + 2 * MEM_SIZE_FIELD; chunk_size += 2 * MEM_SIZE_FIELD + CHUNK_SIZE(next_chunk); mem_unlink_chunk(info, next_chunk); /* either use the full next_chunk or split it */ if (chunk_size < size + 2 * MEM_SIZE_FIELD + MEM_MIN_ALLOC) { info->used_size += chunk_size; info->free_size -= chunk_size; mem_set_used_chunk_size(chunk, chunk_size); } else { new_chunk = (void *)((char *)chunk + MEM_SIZE_FIELD + size + MEM_SIZE_FIELD); new_chunk_size = chunk_size - size - 2 * MEM_SIZE_FIELD; mem_set_chunk_size(new_chunk, new_chunk_size); mem_link_chunk(info, new_chunk); info->used_size += size; info->free_size -= chunk_size; info->free_size += new_chunk_size; mem_set_used_chunk_size(chunk, size); } return chunk; } else if (NULL != (new_chunk = __mem_malloc(info, size))) { memcpy((char *)new_chunk + MEM_SIZE_FIELD, (char *)chunk + MEM_SIZE_FIELD, chunk_size); __mem_free(info, old); return new_chunk; } else { void *tmp = NULL; /* check if there would be enough space if the current chunk */ /* would be freed before allocating a new one */ new_chunk_size = chunk_size; if (0 != next_free) new_chunk_size += CHUNK_SIZE(next_chunk) + 2 * MEM_SIZE_FIELD; if (info->lo_bound < chunk && FREE_CHUNK((char *)chunk - MEM_SIZE_FIELD)) new_chunk_size += CHUNK_SIZE((char *)chunk - MEM_SIZE_FIELD) + 2 * MEM_SIZE_FIELD; if (size > new_chunk_size) return NULL; tmp = zbx_malloc(tmp, chunk_size); memcpy(tmp, (char *)chunk + MEM_SIZE_FIELD, chunk_size); __mem_free(info, old); if (NULL == (new_chunk = __mem_malloc(info, size))) { THIS_SHOULD_NEVER_HAPPEN; exit(EXIT_FAILURE); } memcpy((char *)new_chunk + MEM_SIZE_FIELD, tmp, chunk_size); zbx_free(tmp); return new_chunk; } }