/* 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 "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);

    }

}

APR_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;

}

APR_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);

}

APR_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

};