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/* Copyright 2000-2005 The Apache Software Foundation or its licensors, as
* applicable.
*
* Licensed 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 "apr_buckets.h"
#define APR_WANT_MEMFUNC
#include "apr_want.h"
static apr_status_t pool_bucket_cleanup(void *data)
{
apr_bucket_pool *p = data;
/*
* If the pool gets cleaned up, we have to copy the data out
* of the pool and onto the heap. But the apr_buckets out there
* that point to this pool bucket need to be notified such that
* they can morph themselves into a regular heap bucket the next
* time they try to read. To avoid having to manipulate
* reference counts and b->data pointers, the apr_bucket_pool
* actually _contains_ an apr_bucket_heap as its first element,
* so the two share their apr_bucket_refcount member, and you
* can typecast a pool bucket struct to make it look like a
* regular old heap bucket struct.
*/
p->heap.base = apr_bucket_alloc(p->heap.alloc_len, p->list);
memcpy(p->heap.base, p->base, p->heap.alloc_len);
p->base = NULL;
p->pool = NULL;
return APR_SUCCESS;
}
static apr_status_t pool_bucket_read(apr_bucket *b, const char **str,
apr_size_t *len, apr_read_type_e block)
{
apr_bucket_pool *p = b->data;
const char *base = p->base;
if (p->pool == NULL) {
/*
* pool has been cleaned up... masquerade as a heap bucket from now
* on. subsequent bucket operations will use the heap bucket code.
*/
b->type = &apr_bucket_type_heap;
base = p->heap.base;
}
*str = base + b->start;
*len = b->length;
return APR_SUCCESS;
}
static void pool_bucket_destroy(void *data)
{
apr_bucket_pool *p = data;
/* If the pool is cleaned up before the last reference goes
* away, the data is really now on the heap; heap_destroy() takes
* over. free() in heap_destroy() thinks it's freeing
* an apr_bucket_heap, when in reality it's freeing the whole
* apr_bucket_pool for us.
*/
if (p->pool) {
/* the shared resource is still in the pool
* because the pool has not been cleaned up yet
*/
if (apr_bucket_shared_destroy(p)) {
apr_pool_cleanup_kill(p->pool, p, pool_bucket_cleanup);
apr_bucket_free(p);
}
}
else {
/* the shared resource is no longer in the pool, it's
* on the heap, but this reference still thinks it's a pool
* bucket. we should just go ahead and pass control to
* heap_destroy() for it since it doesn't know any better.
*/
apr_bucket_type_heap.destroy(p);
}
}
APU_DECLARE(apr_bucket *) apr_bucket_pool_make(apr_bucket *b,
const char *buf, apr_size_t length, apr_pool_t *pool)
{
apr_bucket_pool *p;
p = apr_bucket_alloc(sizeof(*p), b->list);
/* XXX: we lose the const qualifier here which indicates
* there's something screwy with the API...
*/
/* XXX: why is this? buf is const, p->base is const... what's
* the problem? --jcw */
p->base = (char *) buf;
p->pool = pool;
p->list = b->list;
b = apr_bucket_shared_make(b, p, 0, length);
b->type = &apr_bucket_type_pool;
/* pre-initialize heap bucket member */
p->heap.alloc_len = length;
p->heap.base = NULL;
p->heap.free_func = apr_bucket_free;
apr_pool_cleanup_register(p->pool, p, pool_bucket_cleanup,
apr_pool_cleanup_null);
return b;
}
APU_DECLARE(apr_bucket *) apr_bucket_pool_create(const char *buf,
apr_size_t length,
apr_pool_t *pool,
apr_bucket_alloc_t *list)
{
apr_bucket *b = apr_bucket_alloc(sizeof(*b), list);
APR_BUCKET_INIT(b);
b->free = apr_bucket_free;
b->list = list;
return apr_bucket_pool_make(b, buf, length, pool);
}
APU_DECLARE_DATA const apr_bucket_type_t apr_bucket_type_pool = {
"POOL", 5, APR_BUCKET_DATA,
pool_bucket_destroy,
pool_bucket_read,
apr_bucket_setaside_noop, /* don't need to setaside thanks to the cleanup*/
apr_bucket_shared_split,
apr_bucket_shared_copy
};
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