Coverage Report

Created: 2023-03-26 06:28

/src/httpd/srclib/apr/buckets/apr_buckets_mmap.c
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/* Licensed to the Apache Software Foundation (ASF) under one or more
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 * contributor license agreements.  See the NOTICE file distributed with
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 * this work for additional information regarding copyright ownership.
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 * The ASF licenses this file to You under the Apache License, Version 2.0
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 * (the "License"); you may not use this file except in compliance with
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 * the License.  You may obtain a copy of the License at
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 *
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 *     http://www.apache.org/licenses/LICENSE-2.0
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 *
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 * Unless required by applicable law or agreed to in writing, software
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 * distributed under the License is distributed on an "AS IS" BASIS,
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 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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 * See the License for the specific language governing permissions and
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 * limitations under the License.
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 */
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#include "apr_buckets.h"
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#if APR_HAS_MMAP
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static apr_status_t mmap_bucket_read(apr_bucket *b, const char **str,
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                                     apr_size_t *length, apr_read_type_e block)
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0
{
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    apr_bucket_mmap *m = b->data;
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    apr_status_t ok;
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    void *addr;
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    if (!m->mmap) {
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        /* the apr_mmap_t was already cleaned up out from under us */
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        return APR_EINVAL;
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    }
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    ok = apr_mmap_offset(&addr, m->mmap, b->start);
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    if (ok != APR_SUCCESS) {
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        return ok;
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    }
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    *str = addr;
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    *length = b->length;
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    return APR_SUCCESS;
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}
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static apr_status_t mmap_bucket_cleanup(void *data)
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{
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    /* the apr_mmap_t is about to disappear out from under us, so we
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     * have no choice but to pretend it doesn't exist anymore.  the
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     * refcount is now useless because there's nothing to refer to
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     * anymore.  so the only valid action on any remaining referrer
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     * is to delete it.  no more reads, no more anything. */
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    apr_bucket_mmap *m = data;
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    m->mmap = NULL;
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    return APR_SUCCESS;
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}
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static void mmap_bucket_destroy(void *data)
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0
{
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    apr_bucket_mmap *m = data;
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    if (apr_bucket_shared_destroy(m)) {
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        if (m->mmap) {
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            apr_pool_cleanup_kill(m->mmap->cntxt, m, mmap_bucket_cleanup);
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            apr_mmap_delete(m->mmap);
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        }
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        apr_bucket_free(m);
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    }
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}
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/*
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 * XXX: are the start and length arguments useful?
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 */
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APR_DECLARE(apr_bucket *) apr_bucket_mmap_make(apr_bucket *b, apr_mmap_t *mm,
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                                               apr_off_t start,
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                                               apr_size_t length)
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{
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    apr_bucket_mmap *m;
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    m = apr_bucket_alloc(sizeof(*m), b->list);
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    m->mmap = mm;
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    apr_pool_cleanup_register(mm->cntxt, m, mmap_bucket_cleanup,
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                              apr_pool_cleanup_null);
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    b = apr_bucket_shared_make(b, m, start, length);
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    b->type = &apr_bucket_type_mmap;
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    return b;
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}
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APR_DECLARE(apr_bucket *) apr_bucket_mmap_create(apr_mmap_t *mm,
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                                                 apr_off_t start,
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                                                 apr_size_t length,
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                                                 apr_bucket_alloc_t *list)
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{
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    apr_bucket *b = apr_bucket_alloc(sizeof(*b), list);
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    APR_BUCKET_INIT(b);
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    b->free = apr_bucket_free;
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    b->list = list;
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    return apr_bucket_mmap_make(b, mm, start, length);
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}
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static apr_status_t mmap_bucket_setaside(apr_bucket *b, apr_pool_t *p)
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{
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    apr_bucket_mmap *m = b->data;
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    apr_mmap_t *mm = m->mmap;
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    apr_mmap_t *new_mm;
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    apr_status_t ok;
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    if (!mm) {
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        /* the apr_mmap_t was already cleaned up out from under us */
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        return APR_EINVAL;
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    }
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    /* shortcut if possible */
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    if (apr_pool_is_ancestor(mm->cntxt, p)) {
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        return APR_SUCCESS;
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    }
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    /* duplicate apr_mmap_t into new pool */
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    ok = apr_mmap_dup(&new_mm, mm, p);
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    if (ok != APR_SUCCESS) {
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        return ok;
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    }
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    /* decrement refcount on old apr_bucket_mmap */
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    mmap_bucket_destroy(m);
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    /* create new apr_bucket_mmap pointing to new apr_mmap_t */
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    apr_bucket_mmap_make(b, new_mm, b->start, b->length);
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    return APR_SUCCESS;
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}
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APR_DECLARE_DATA const apr_bucket_type_t apr_bucket_type_mmap = {
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    "MMAP", 5, APR_BUCKET_DATA,
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    mmap_bucket_destroy,
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    mmap_bucket_read,
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    mmap_bucket_setaside,
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    apr_bucket_shared_split,
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    apr_bucket_shared_copy
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};
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#endif