diff options
Diffstat (limited to 'buckets/apr_buckets_alloc.c')
| -rw-r--r-- | buckets/apr_buckets_alloc.c | 243 |
1 files changed, 243 insertions, 0 deletions
diff --git a/buckets/apr_buckets_alloc.c b/buckets/apr_buckets_alloc.c new file mode 100644 index 0000000..2d6f214 --- /dev/null +++ b/buckets/apr_buckets_alloc.c @@ -0,0 +1,243 @@ +/* Licensed to the Apache Software Foundation (ASF) under one or more + * contributor license agreements. See the NOTICE file distributed with + * this work for additional information regarding copyright ownership. + * The ASF licenses this file to You under the Apache License, Version 2.0 + * (the "License"); you may not use this file except in compliance with + * the License. You may obtain a copy of the License at + * + * http://www.apache.org/licenses/LICENSE-2.0 + * + * Unless required by applicable law or agreed to in writing, software + * distributed under the License is distributed on an "AS IS" BASIS, + * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + * See the License for the specific language governing permissions and + * limitations under the License. + */ + +#include <stdlib.h> + +#include "apr_buckets.h" +#include "apr_allocator.h" +#include "apr_version.h" + +#define ALLOC_AMT (8192 - APR_MEMNODE_T_SIZE) + +typedef struct node_header_t { + apr_size_t size; + apr_bucket_alloc_t *alloc; + apr_memnode_t *memnode; + struct node_header_t *next; +} node_header_t; + +#define SIZEOF_NODE_HEADER_T APR_ALIGN_DEFAULT(sizeof(node_header_t)) +#define SMALL_NODE_SIZE (APR_BUCKET_ALLOC_SIZE + SIZEOF_NODE_HEADER_T) + +/** A list of free memory from which new buckets or private bucket + * structures can be allocated. + */ +struct apr_bucket_alloc_t { + apr_pool_t *pool; + apr_allocator_t *allocator; + node_header_t *freelist; + apr_memnode_t *blocks; +}; + +static apr_status_t alloc_cleanup(void *data) +{ + apr_bucket_alloc_t *list = data; +#if APR_POOL_DEBUG + apr_allocator_t *allocator = NULL; +#endif + +#if APR_POOL_DEBUG + if (list->pool && list->allocator != apr_pool_allocator_get(list->pool)) { + allocator = list->allocator; + } +#endif + + apr_allocator_free(list->allocator, list->blocks); + +#if APR_POOL_DEBUG + if (allocator) { + apr_allocator_destroy(allocator); + } +#endif + + return APR_SUCCESS; +} + +APU_DECLARE_NONSTD(apr_bucket_alloc_t *) apr_bucket_alloc_create(apr_pool_t *p) +{ + apr_allocator_t *allocator = apr_pool_allocator_get(p); + apr_bucket_alloc_t *list; + +#if APR_POOL_DEBUG + /* may be NULL for debug mode. */ + if (allocator == NULL) { + if (apr_allocator_create(&allocator) != APR_SUCCESS) { + apr_abortfunc_t fn = apr_pool_abort_get(p); + if (fn) + (fn)(APR_ENOMEM); + abort(); + } + } +#endif + list = apr_bucket_alloc_create_ex(allocator); + if (list == NULL) { + apr_abortfunc_t fn = apr_pool_abort_get(p); + if (fn) + (fn)(APR_ENOMEM); + abort(); + } + list->pool = p; + apr_pool_cleanup_register(list->pool, list, alloc_cleanup, + apr_pool_cleanup_null); + + return list; +} + +APU_DECLARE_NONSTD(apr_bucket_alloc_t *) apr_bucket_alloc_create_ex( + apr_allocator_t *allocator) +{ + apr_bucket_alloc_t *list; + apr_memnode_t *block; + + block = apr_allocator_alloc(allocator, ALLOC_AMT); + if (!block) { + return NULL; + } + list = (apr_bucket_alloc_t *)block->first_avail; + list->pool = NULL; + list->allocator = allocator; + list->freelist = NULL; + list->blocks = block; + block->first_avail += APR_ALIGN_DEFAULT(sizeof(*list)); + + return list; +} + +APU_DECLARE_NONSTD(void) apr_bucket_alloc_destroy(apr_bucket_alloc_t *list) +{ + if (list->pool) { + apr_pool_cleanup_kill(list->pool, list, alloc_cleanup); + } + + apr_allocator_free(list->allocator, list->blocks); + +#if APR_POOL_DEBUG + if (list->pool && list->allocator != apr_pool_allocator_get(list->pool)) { + apr_allocator_destroy(list->allocator); + } +#endif +} + +APU_DECLARE_NONSTD(apr_size_t) apr_bucket_alloc_aligned_floor(apr_bucket_alloc_t *list, + apr_size_t size) +{ + if (size <= SMALL_NODE_SIZE) { + size = SMALL_NODE_SIZE; + } + else { +#if APR_VERSION_AT_LEAST(1,6,0) + if (size < APR_MEMNODE_T_SIZE) { + size = apr_allocator_align(list->allocator, 0); + } + else { + size = apr_allocator_align(list->allocator, + size - APR_MEMNODE_T_SIZE); + } +#else + /* Assumes the minimum (default) allocator's boundary of 4K and + * minimum (immutable before APR-1.6.x) allocation size of 8K, + * hence possibly (yet unlikely) under-estimating the floor... + */ + size = APR_ALIGN(size, 4096); + if (size < 8192) { + size = 8192; + } +#endif + size -= APR_MEMNODE_T_SIZE; + } + size -= SIZEOF_NODE_HEADER_T; + return size; +} + +APU_DECLARE_NONSTD(void *) apr_bucket_alloc(apr_size_t size, + apr_bucket_alloc_t *list) +{ + node_header_t *node; + apr_memnode_t *active = list->blocks; + char *endp; + + size += SIZEOF_NODE_HEADER_T; + if (size <= SMALL_NODE_SIZE) { + if (list->freelist) { + node = list->freelist; + list->freelist = node->next; + } + else { + endp = active->first_avail + SMALL_NODE_SIZE; + if (endp >= active->endp) { + list->blocks = apr_allocator_alloc(list->allocator, ALLOC_AMT); + if (!list->blocks) { + list->blocks = active; + return NULL; + } + list->blocks->next = active; + active = list->blocks; + endp = active->first_avail + SMALL_NODE_SIZE; + } + node = (node_header_t *)active->first_avail; + node->alloc = list; + node->memnode = active; + node->size = SMALL_NODE_SIZE; + active->first_avail = endp; + } + } + else { + apr_memnode_t *memnode = apr_allocator_alloc(list->allocator, size); + if (!memnode) { + return NULL; + } + node = (node_header_t *)memnode->first_avail; + node->alloc = list; + node->memnode = memnode; + node->size = size; + } + return ((char *)node) + SIZEOF_NODE_HEADER_T; +} + +#ifdef APR_BUCKET_DEBUG +#if APR_HAVE_STDLIB_H +#include <stdlib.h> +#endif +static void check_not_already_free(node_header_t *node) +{ + apr_bucket_alloc_t *list = node->alloc; + node_header_t *curr = list->freelist; + + while (curr) { + if (node == curr) { + abort(); + } + curr = curr->next; + } +} +#else +#define check_not_already_free(node) +#endif + +APU_DECLARE_NONSTD(void) apr_bucket_free(void *mem) +{ + node_header_t *node = (node_header_t *)((char *)mem - SIZEOF_NODE_HEADER_T); + apr_bucket_alloc_t *list = node->alloc; + + if (node->size == SMALL_NODE_SIZE) { + check_not_already_free(node); + node->next = list->freelist; + list->freelist = node; + } + else { + apr_allocator_free(list->allocator, node->memnode); + } +} |