/***************************************************************************

 * Copyright (c) 2009-2010 Open Information Security Foundation

 * Copyright (c) 2010-2013 Qualys, Inc.

 * All rights reserved.

 * 

 * Redistribution and use in source and binary forms, with or without

 * modification, are permitted provided that the following conditions are

 * met:

 * 

 * - Redistributions of source code must retain the above copyright

 *   notice, this list of conditions and the following disclaimer.

 * - Redistributions in binary form must reproduce the above copyright

 *   notice, this list of conditions and the following disclaimer in the

 *   documentation and/or other materials provided with the distribution.

 * - Neither the name of the Qualys, Inc. nor the names of its

 *   contributors may be used to endorse or promote products derived from

 *   this software without specific prior written permission.

 * 

 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS

 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT

 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR

 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT

 * HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,

 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT

 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,

 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY

 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT

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 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

 ***************************************************************************/

/**

 * @file

 * @author Ivan Ristic <ivanr@webkreator.com>

 */

#include "htp_config_auto.h"

#include "htp_private.h"

htp_hook_t *htp_hook_copy(const htp_hook_t *hook) {

    if (hook == NULL) return NULL;

    htp_hook_t *copy = htp_hook_create();

    if (copy == NULL) return NULL;

    for (size_t i = 0, n = htp_list_size(hook->callbacks); i < n; i++) {

        htp_callback_t *callback = htp_list_get(hook->callbacks, i);

        if (htp_hook_register(&copy, callback->fn) != HTP_OK) {

            htp_hook_destroy(copy);

            return NULL;

        }

    }

    return copy;

}

htp_hook_t *htp_hook_create(void) {

    htp_hook_t *hook = calloc(1, sizeof (htp_hook_t));

    if (hook == NULL) return NULL;

    hook->callbacks = (htp_list_array_t *) htp_list_array_create(4);

    if (hook->callbacks == NULL) {

        free(hook);

        return NULL;

    }

    return hook;

}

void htp_hook_destroy(htp_hook_t *hook) {

    if (hook == NULL) return;

    for (size_t i = 0, n = htp_list_size(hook->callbacks); i < n; i++) {

        free((htp_callback_t *) htp_list_get(hook->callbacks, i));

    }

    htp_list_array_destroy(hook->callbacks);

    free(hook);

}

htp_status_t htp_hook_register(htp_hook_t **hook, const htp_callback_fn_t callback_fn) {

    if (hook == NULL) return HTP_ERROR;

    htp_callback_t *callback = calloc(1, sizeof (htp_callback_t));

    if (callback == NULL) return HTP_ERROR;

    callback->fn = callback_fn;

    // Create a new hook if one does not exist

    int hook_created = 0;

    if (*hook == NULL) {

        hook_created = 1;

        *hook = htp_hook_create();

        if (*hook == NULL) {

            free(callback);

            return HTP_ERROR;

        }

    }

    // Add callback 

    if (htp_list_array_push((*hook)->callbacks, callback) != HTP_OK) {

        if (hook_created) {

            free(*hook);

        }

        free(callback);

        return HTP_ERROR;

    }

    return HTP_OK;

}

htp_status_t htp_hook_run_all(htp_hook_t *hook, void *user_data) {

    if (hook == NULL) return HTP_OK;

    // Loop through the registered callbacks, giving each a chance to run.

    for (size_t i = 0, n = htp_list_size(hook->callbacks); i < n; i++) {

        htp_callback_t *callback = htp_list_get(hook->callbacks, i);

        htp_status_t rc = callback->fn(user_data);

        // A hook can return HTP_OK to say that it did some work,

        // or HTP_DECLINED to say that it did no work. Anything else

        // is treated as an error.

        if ((rc != HTP_OK) && (rc != HTP_DECLINED)) {

            return rc;

        }

    }

    return HTP_OK;

}

htp_status_t htp_hook_run_one(htp_hook_t *hook, void *user_data) {

    if (hook == NULL) return HTP_DECLINED;

    for (size_t i = 0, n = htp_list_size(hook->callbacks); i < n; i++) {

        htp_callback_t *callback = htp_list_get(hook->callbacks, i);

        htp_status_t rc = callback->fn(user_data);

        // A hook can return HTP_DECLINED to say that it did no work,

        // and we'll ignore that. If we see HTP_OK or anything else,

        // we stop processing (because it was either a successful

        // handling or an error).

        if (rc != HTP_DECLINED) {

            // Return HTP_OK or an error.

            return rc;

        }

    }

    // No hook wanted to process the callback.

    return HTP_DECLINED;

}