/*
  * $Id$
  *
  * Script callbacks -- they add the ability to register callback
  * functions which are always called when script for request
  * processing is entered or left
  *

  *

  * Copyright (C) 2001-2003 FhG Fokus

  *
  * This file is part of ser, a free SIP server.
  *
  * ser is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
  * the Free Software Foundation; either version 2 of the License, or
  * (at your option) any later version
  *
  * For a license to use the ser software under conditions
  * other than those described here, or to purchase support for this
  * software, please contact iptel.org by e-mail at the following addresses:
  *    info@iptel.org
  *
  * ser is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  * GNU General Public License for more details.
  *
  * You should have received a copy of the GNU General Public License 
  * along with this program; if not, write to the Free Software 
  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA

  *
  * History:

  * --------

  *  2003-03-29  cleaning pkg allocation introduced (jiri)

  *  2003-03-19  replaced all mallocs/frees w/ pkg_malloc/pkg_free (andrei)

  *  2005-02-13  script callbacks devided into request and reply types (bogdan)

  *  2009-06-01  Added pre- and post-script callback support for all types
  *		of route blocks. (Miklos)

  */

 /*!
  * \file
  * \brief SIP-router core :: 
  * \ingroup core
  * Module: \ref core
  */
 

 #include <stdlib.h>
 #include "script_cb.h"
 #include "dprint.h"
 #include "error.h"

 #include "mem/mem.h"

 /* Number of cb types = last cb type */

 #define SCRIPT_CB_NUM	(MAX_CB_TYPE-1)

 static struct script_cb *pre_script_cb[SCRIPT_CB_NUM];
 static struct script_cb *post_script_cb[SCRIPT_CB_NUM];

 /* Add a script callback to the beginning of the linked list.
  * Returns -1 on error
  */

 static inline int add_callback( struct script_cb **list,
 	cb_function f, void *param)

 {
 	struct script_cb *new_cb;
 

 	new_cb=pkg_malloc(sizeof(struct script_cb));

 	if (new_cb==0) {

 		LOG(L_CRIT, "add_script_callback: out of memory\n");

 		return -1;

 	}

 	new_cb->cbf = f;
 	new_cb->param = param;
 	/* link at the beginning of the list */
 	new_cb->next = *list;
 	*list = new_cb;
 	return 0;
 }
 

 /* Register pre- or post-script callbacks.
  * Returns -1 on error, 0 on success
  */
 int register_script_cb( cb_function f, unsigned int flags, void *param )

 {

 	struct script_cb	**cb_array;
 	int	i;
 

 	/* type checkings */

 	if ( (flags&((1<<SCRIPT_CB_NUM)-1))==0 ) {
 		LOG(L_BUG, "register_script_cb: callback flag not specified\n");
 		return -1;
 	}
 	if ( (flags&(~(PRE_SCRIPT_CB|POST_SCRIPT_CB))) >= 1<<SCRIPT_CB_NUM ) {
 		LOG(L_BUG, "register_script_cb: unsupported callback flags: %u\n",
 			flags);
 		return -1;

 	}

 	if ( (flags&(PRE_SCRIPT_CB|POST_SCRIPT_CB))==0 ||
 	(flags&PRE_SCRIPT_CB && flags&POST_SCRIPT_CB) ) {
 		LOG(L_BUG, "register_script_cb: callback POST or PRE type must "

 			"be exactly one\n");

 		return -1;

 	}
 

 	if (flags&PRE_SCRIPT_CB)
 		cb_array = pre_script_cb;
 	else
 		cb_array = post_script_cb;
 
 	/* Add the callback to the lists.
 	 * (as many times as many flags are set)
 	 */
 	for (i=0; i<SCRIPT_CB_NUM; i++) {
 		if ((flags&(1<<i)) == 0)
 			continue;
 		if (add_callback(&cb_array[i], f, param) < 0)
 			goto add_error;

 	}
 	return 0;

 add_error:

 	LOG(L_ERR,"register_script_cb: failed to add callback\n");

 	return -1;

 }
 

 int init_script_cb()
 {
 	memset(pre_script_cb, 0, SCRIPT_CB_NUM * sizeof(struct script_cb *));
 	memset(post_script_cb, 0, SCRIPT_CB_NUM * sizeof(struct script_cb *));
 	return 0;
 }

 
 static inline void destroy_cb_list(struct script_cb **list)

 {

 	struct script_cb *foo;
 
 	while( *list ) {
 		foo = *list;
 		*list = (*list)->next;
 		pkg_free( foo );
 	}
 }

 void destroy_script_cb()
 {

 	int	i;

 	for (i=0; i<SCRIPT_CB_NUM; i++) {
 		destroy_cb_list(&pre_script_cb[i]);
 		destroy_cb_list(&post_script_cb[i]);
 	}
 }

 /* Execute pre-script callbacks of a given type.
  * Returns 0 on error, 1 on success
  */
 int exec_pre_script_cb( struct sip_msg *msg, enum script_cb_type type)

 {

 	struct script_cb	*cb;
 	unsigned int	flags;
 
 #ifdef EXTRA_DEBUG
 	if (type >= SCRIPT_CB_NUM) {
 		LOG(L_BUG, "exec_pre_script_cb: Uknown callback type\n");
 		abort();
 	}
 #endif

 	flags = PRE_SCRIPT_CB | (1<<(type-1));
 	for (cb=pre_script_cb[type-1]; cb ; cb=cb->next ) {

 		/* stop on error */

 		if (cb->cbf(msg, flags, cb->param)==0)

 			return 0;
 	}
 	return 1;

 }
 

 /* Execute post-script callbacks of a given type.
  * Always returns 1, success.
  */
 int exec_post_script_cb( struct sip_msg *msg, enum script_cb_type type)

 {

 	struct script_cb	*cb;
 	unsigned int	flags;
 
 #ifdef EXTRA_DEBUG
 	if (type >= SCRIPT_CB_NUM) {
 		LOG(L_BUG, "exec_pre_script_cb: Uknown callback type\n");
 		abort();
 	}
 #endif

 	flags = POST_SCRIPT_CB | (1<<(type-1));
 	for (cb=post_script_cb[type-1]; cb ; cb=cb->next){

 		cb->cbf(msg, flags, cb->param);

 	}
 	return 1;
 }