/* 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"

#if APR_HAS_MMAP

static apr_status_t mmap_bucket_read(apr_bucket *b, const char **str,

                                     apr_size_t *length, apr_read_type_e block)

{

    apr_bucket_mmap *m = b->data;

    apr_status_t ok;

    void *addr;

    if (!m->mmap) {

        /* the apr_mmap_t was already cleaned up out from under us */

        return APR_EINVAL;

    }

    ok = apr_mmap_offset(&addr, m->mmap, b->start);

    if (ok != APR_SUCCESS) {

        return ok;

    }

    *str = addr;

    *length = b->length;

    return APR_SUCCESS;

}

static apr_status_t mmap_bucket_cleanup(void *data)

{

    /* the apr_mmap_t is about to disappear out from under us, so we

     * have no choice but to pretend it doesn't exist anymore.  the

     * refcount is now useless because there's nothing to refer to

     * anymore.  so the only valid action on any remaining referrer

     * is to delete it.  no more reads, no more anything. */

    apr_bucket_mmap *m = data;

    m->mmap = NULL;

    return APR_SUCCESS;

}

static void mmap_bucket_destroy(void *data)

{

    apr_bucket_mmap *m = data;

    if (apr_bucket_shared_destroy(m)) {

        if (m->mmap) {

            apr_pool_cleanup_kill(m->mmap->cntxt, m, mmap_bucket_cleanup);

            apr_mmap_delete(m->mmap);

        }

        apr_bucket_free(m);

    }

}

/*

 * XXX: are the start and length arguments useful?

 */

APR_DECLARE(apr_bucket *) apr_bucket_mmap_make(apr_bucket *b, apr_mmap_t *mm,

                                               apr_off_t start,

                                               apr_size_t length)

{

    apr_bucket_mmap *m;

    m = apr_bucket_alloc(sizeof(*m), b->list);

    m->mmap = mm;

    apr_pool_cleanup_register(mm->cntxt, m, mmap_bucket_cleanup,

                              apr_pool_cleanup_null);

    b = apr_bucket_shared_make(b, m, start, length);

    b->type = &apr_bucket_type_mmap;

    return b;

}

APR_DECLARE(apr_bucket *) apr_bucket_mmap_create(apr_mmap_t *mm,

                                                 apr_off_t start,

                                                 apr_size_t length,

                                                 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_mmap_make(b, mm, start, length);

}

static apr_status_t mmap_bucket_setaside(apr_bucket *b, apr_pool_t *p)

{

    apr_bucket_mmap *m = b->data;

    apr_mmap_t *mm = m->mmap;

    apr_mmap_t *new_mm;

    apr_status_t ok;

    if (!mm) {

        /* the apr_mmap_t was already cleaned up out from under us */

        return APR_EINVAL;

    }

    /* shortcut if possible */

    if (apr_pool_is_ancestor(mm->cntxt, p)) {

        return APR_SUCCESS;

    }

    /* duplicate apr_mmap_t into new pool */

    ok = apr_mmap_dup(&new_mm, mm, p);

    if (ok != APR_SUCCESS) {

        return ok;

    }

    /* decrement refcount on old apr_bucket_mmap */

    mmap_bucket_destroy(m);

    /* create new apr_bucket_mmap pointing to new apr_mmap_t */

    apr_bucket_mmap_make(b, new_mm, b->start, b->length);

    return APR_SUCCESS;

}

APR_DECLARE_DATA const apr_bucket_type_t apr_bucket_type_mmap = {

    "MMAP", 5, APR_BUCKET_DATA,

    mmap_bucket_destroy,

    mmap_bucket_read,

    mmap_bucket_setaside,

    apr_bucket_shared_split,

    apr_bucket_shared_copy

};

#endif