/*

 * Copyright (C) 2001-2003 FhG Fokus

 *

 * This file is part of opensips, a free SIP server.

 *

 * opensips 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

 *

 * opensips 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., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301  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)

 *  2009-05-21  keep the callback lists in the same order as callbacks

                 were registered (bogdan)

 */

/*!

 * \file

 * \brief Script callbacks

 */

#include <stdlib.h>

#include "script_cb.h"

#include "dprint.h"

#include "error.h"

#include "mem/mem.h"

static struct script_cb *pre_req_cb=0;

static struct script_cb *post_req_cb=0;

static struct script_cb *pre_rpl_cb=0;

static struct script_cb *post_rpl_cb=0;

static struct script_cb *parse_err_cb=0;

static unsigned int cb_id=0;

struct raw_processing_cb_list* pre_processing_cb_list = NULL;

struct raw_processing_cb_list* post_processing_cb_list = NULL;

static inline int add_callback( struct script_cb **list,

  cb_function f, void *param, int prio)

{

  struct script_cb *last_cb;

  struct script_cb *new_cb;

  new_cb=pkg_malloc(sizeof(struct script_cb));

  if (new_cb==0) {

    LM_ERR("out of pkg memory\n");

    return -1;

  }

  new_cb->cbf = f;

  new_cb->id = cb_id++;

  new_cb->param = param;

  new_cb->next = NULL;

  new_cb->prio = prio;

  /* descending priority sorting; equal priorities are inserted at the end

    it is important to keep the order at register time, as this reflects the

    order of loading/init the modules --bogdan */

  if (*list==NULL) {

    *list = new_cb;

  } else if ((*list)->prio < prio) {

    new_cb->next = *list;

    *list = new_cb;

  } else {

    for (last_cb = *list;

         last_cb->next && last_cb->next->prio >= prio;

         last_cb = last_cb->next)

      ;

    new_cb->next = last_cb->next;

    last_cb->next = new_cb;

  }

  return 0;

}

int __register_script_cb( cb_function f, int type, void *param, int prio)

{

  /* type checkings */

  if ( (type&(REQ_TYPE_CB|RPL_TYPE_CB|PARSE_ERR_CB))==0 ) {

    LM_CRIT("request / reply / error type not specified\n");

    goto error;

  }

  if ( (type&(PRE_SCRIPT_CB|POST_SCRIPT_CB|PARSE_ERR_CB))==0 ||

  (type&PRE_SCRIPT_CB && type&POST_SCRIPT_CB) ) {

    LM_CRIT("callback POST or PRE type must be exactly one\n");

    goto error;

  }

  if (type&PARSE_ERR_CB) {

    if (add_callback( &parse_err_cb, f, param, prio)<0)

      goto add_error;

  }

  if (type&REQ_TYPE_CB) {

    /* callback for request script */

    if (type&PRE_SCRIPT_CB) {

      if (add_callback( &pre_req_cb, f, param, prio)<0)

        goto add_error;

    } else if (type&POST_SCRIPT_CB) {

      if (add_callback( &post_req_cb, f, param, prio)<0)

        goto add_error;

    }

  }

  if (type&RPL_TYPE_CB) {

    /* callback (also) for reply script */

    if (type&PRE_SCRIPT_CB) {

      if (add_callback( &pre_rpl_cb, f, param, prio)<0)

        goto add_error;

    } else if (type&POST_SCRIPT_CB) {

      if (add_callback( &post_rpl_cb, f, param, prio)<0)

        goto add_error;

    }

  }

  return 0;

add_error:

  LM_ERR("failed to add callback\n");

error:

  return -1;

}

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(void)

{

  destroy_cb_list( &pre_req_cb  );

  destroy_cb_list( &post_req_cb );

  destroy_cb_list( &pre_rpl_cb  );

  destroy_cb_list( &post_req_cb );

  destroy_cb_list( &parse_err_cb );

}

static inline int exec_pre_cb( struct sip_msg *msg, struct script_cb *cb)

{

  int bitmask = SCB_RUN_ALL;

  for ( ; cb ; cb=cb->next ) {

    bitmask &= cb->cbf(msg, cb->param);

    if (bitmask == SCB_DROP_MSG)

      break;

  }

  return bitmask;

}

static inline int exec_post_cb( struct sip_msg *msg, struct script_cb *cb)

{

  for ( ; cb ; cb=cb->next){

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

  }

  return 1;

}

int exec_pre_req_cb( struct sip_msg *msg)

{

  return exec_pre_cb( msg, pre_req_cb);

}

int exec_pre_rpl_cb( struct sip_msg *msg)

{

  return exec_pre_cb( msg, pre_rpl_cb);

}

int exec_post_req_cb( struct sip_msg *msg)

{

  return exec_post_cb( msg, post_req_cb);

}

int exec_post_rpl_cb( struct sip_msg *msg)

{

  return exec_post_cb( msg, post_rpl_cb);

}

int exec_parse_err_cb( struct sip_msg *msg)

{

  return exec_post_cb( msg, parse_err_cb);

}

static inline int insert_raw_processing_cb(raw_processing_func f, int type, struct raw_processing_cb_list* list, char freeable)

{

  struct raw_processing_cb_list *elem;

  if (f == NULL) {

    LM_ERR("null callback\n");

    return -1;

  }

  elem = pkg_malloc(sizeof(struct raw_processing_cb_list));

  if (elem == NULL) {

    LM_ERR("no more pkg mem\n");

    return -1;

  }

  elem->f = f;

  elem->freeable = freeable;

  elem->next = NULL;

  if (list == NULL) {

    list = elem;

    return !(type==PRE_RAW_PROCESSING ? (pre_processing_cb_list=list)

                      : (post_processing_cb_list=list));

  } else {

    while (list->next != NULL)

      list = list->next;

    list->next=elem;

  }

  return 0;

}

int register_pre_raw_processing_cb(raw_processing_func f, int type, char freeable)

{

  return  insert_raw_processing_cb(f, type, pre_processing_cb_list, freeable);

}

int register_post_raw_processing_cb(raw_processing_func f, int type, char freeable)

{

  return  insert_raw_processing_cb(f, type, post_processing_cb_list, freeable);

}

int run_pre_raw_processing_cb(int type, str* data, struct sip_msg* msg)

{

  return run_raw_processing_cb(type, data, msg, pre_processing_cb_list);

}

int run_post_raw_processing_cb(int type, str* data, struct sip_msg* msg)

{

  return run_raw_processing_cb(type, data, msg, post_processing_cb_list);

}

int run_raw_processing_cb(int type, str *data, struct sip_msg* msg, struct raw_processing_cb_list* list)

{

  struct raw_processing_cb_list *foo=NULL, *last_good=NULL, *head=NULL;

  char *initial_data = data->s, *input_data;

  int rc;

  if (list == NULL)

    return 0;

  while (list) {

    input_data = data->s;

    /* a return code bigger than 0 means you want to keep the callback */

    if ((rc = list->f(data, msg)) < 0) {

      LM_ERR("failed to run callback\n");

      return -1;

    }

    if (input_data != initial_data && input_data != data->s)

      pkg_free(input_data);

    foo = list;

    list = list->next;

    if (foo != NULL) {

      if (foo->freeable && rc == 0) {

        /* foo will be gone so link the last good element

         * to the next one */

        if (last_good)

          last_good->next=list;

        pkg_free(foo);

      } else {

        /* keep the first element not to be freed */

        if (head == NULL)

          head = foo;

        /* and keep track of the last viable element to link with the

         * next viable element */

        last_good = foo;

      }

    }

  }

  return !(type==PRE_RAW_PROCESSING?(pre_processing_cb_list=head)

                    :(post_processing_cb_list=head));

}