mod_magick.h

/* 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.
 */

/*
 * mod_magick.h
 *
 *  Created on: 03 Aug 2020
 *      Author: minfrin
 */

#ifndef MOD_MAGICK_H_
#define MOD_MAGICK_H_

#include <apr_buckets.h>
#include <wand/wand_api.h>

/**
 * The MAGICK bucket type.  This bucket represents a magick wand. If this bucket
 * is still available when the pool is cleared, the data is copied on to the heap
 * and becomes a MAGICK_HEAP bucket.
 */
AP_DECLARE_DATA extern const apr_bucket_type_t ap_bucket_type_magick;

/**
 * The MAGICK_HEAP bucket type.  This bucket represents a data that was generated
 * from a magick wand.
 */
AP_DECLARE_DATA extern const apr_bucket_type_t ap_bucket_type_magick_heap;

/**
 * Determine if a bucket is a MAGICK bucket
 * @param e The bucket to inspect
 * @return true or false
 */
#define AP_BUCKET_IS_MAGICK(e)        ((e)->type == &ap_bucket_type_magick)

/**
 * Determine if a bucket is a MAGICK_HEAP bucket
 * @param e The bucket to inspect
 * @return true or false
 */
#define AP_BUCKET_IS_MAGICK_HEAP(e)    ((e)->type == &ap_bucket_type_magick_heap)

/**
 * Make the bucket passed in a Magick (MAGICK) bucket
 * @param b The bucket to make into an EOR bucket
 * @param wand The wand to destroy when this bucket is destroyed
 * @return The new bucket, or NULL if allocation failed
 */
AP_DECLARE(apr_bucket *) ap_bucket_magick_make(apr_bucket *b);

/**
 * Create a bucket referring to a Magick Wand (MAGICK). This bucket
 * holds a pointer to the wand, so that the request can be
 * destroyed right after all of the output has been sent to the client.
 *
 * @param list The freelist from which this bucket should be allocated
 * @param wand The wand to destroy when this bucket is destroyed
 * @return The new bucket, or NULL if allocation failed
 */
AP_DECLARE(apr_bucket *) ap_bucket_magick_create(apr_bucket_alloc_t *list);

/** @see apr_bucket_pool */
typedef struct ap_bucket_magick ap_bucket_magick;
/**
 * A bucket referring to data generated by a Magick Wand.
 */
struct ap_bucket_magick {
    /** Number of buckets using this memory */
    apr_bucket_refcount  refcount;
    /** The start of the data actually allocated.
     */
    char    *base;
    /** how much memory was allocated */
    apr_size_t  alloc_len;
    /** The block of data actually allocated from the pool.
     * Segments of this block are referenced by adjusting
     * the start and length of the apr_bucket accordingly.
     * This will be NULL after the pool gets cleaned up.
     */
    /** The magick wand wrapped by this bucket. */
    MagickWand *wand;
};

#endif /* MOD_MAGICK_H_ */