res/res_pjsip_pidf_body_generator.c

   1 /*
   2  * asterisk -- An open source telephony toolkit.
   3  *
   4  * Copyright (C) 2014, Digium, Inc.
   5  *
   6  * Mark Michelson <mmichelson@digium.com>
   7  *
   8  * See http://www.asterisk.org for more information about
   9  * the Asterisk project. Please do not directly contact
  10  * any of the maintainers of this project for assistance;
  11  * the project provides a web site, mailing lists and IRC
  12  * channels for your use.
  13  *
  14  * This program is free software, distributed under the terms of
  15  * the GNU General Public License Version 2. See the LICENSE file
  16  * at the top of the source tree.
  17  */
  18
  19 /*** MODULEINFO
  20         <depend>pjproject</depend>
  21         <depend>res_pjsip</depend>
  22         <depend>res_pjsip_pubsub</depend>
  23         <support_level>core</support_level>
  24  ***/
  25
  26 #include "asterisk.h"
  27
  28 #include <pjsip.h>
  29 #include <pjsip_simple.h>
  30 #include <pjlib.h>
  31
  32 #include "asterisk/module.h"
  33 #include "asterisk/res_pjsip.h"
  34 #include "asterisk/res_pjsip_pubsub.h"
  35 #include "asterisk/res_pjsip_presence_xml.h"
  36 #include "asterisk/res_pjsip_body_generator_types.h"
  37
  38 static void *pidf_allocate_body(void *data)
  39 {
  40         struct ast_sip_exten_state_data *state_data = data;
  41         char *local = ast_strdupa(state_data->local);
  42         pjpidf_pres *pres;
  43         pj_str_t entity;
  44
  45         pres = pjpidf_create(state_data->pool, pj_cstr(&entity, ast_strip_quoted(local, "<", ">")));
  46
  47         return pres;
  48 }
  49
  50 static int pidf_generate_body_content(void *body, void *data)
  51 {
  52         pjpidf_tuple *tuple;
  53         pj_str_t note, id, contact, priority;
  54         char *statestring = NULL, *pidfstate = NULL, *pidfnote = NULL;
  55         enum ast_sip_pidf_state local_state;
  56         char sanitized[PJSIP_MAX_URL_SIZE];
  57         pjpidf_pres *pres = body;
  58         struct ast_sip_exten_state_data *state_data = data;
  59
  60         ast_sip_presence_exten_state_to_str(state_data->exten_state, &statestring,
  61                         &pidfstate, &pidfnote, &local_state);
  62
  63         if (!pjpidf_pres_add_note(state_data->pool, pres, pj_cstr(&note, pidfnote))) {
  64                 ast_log(LOG_WARNING, "Unable to add note to PIDF presence\n");
  65                 return -1;
  66         }
  67
  68         if (!(tuple = pjpidf_pres_add_tuple(state_data->pool, pres,
  69                                         pj_cstr(&id, state_data->exten)))) {
  70                 ast_log(LOG_WARNING, "Unable to create PIDF tuple\n");
  71                 return -1;
  72         }
  73
  74         ast_sip_sanitize_xml(state_data->remote, sanitized, sizeof(sanitized));
  75         pjpidf_tuple_set_contact(state_data->pool, tuple, pj_cstr(&contact, sanitized));
  76         pjpidf_tuple_set_contact_prio(state_data->pool, tuple, pj_cstr(&priority, "1"));
  77         pjpidf_status_set_basic_open(pjpidf_tuple_get_status(tuple),
  78                         local_state == NOTIFY_OPEN);
  79
  80         return 0;
  81 }
  82
  83 #define MAX_STRING_GROWTHS 5
  84
  85 static void pidf_to_string(void *body, struct ast_str **str)
  86 {
  87         int size;
  88         int growths = 0;
  89         pjpidf_pres *pres = body;
  90
  91         do {
  92                 size = pjpidf_print(pres, ast_str_buffer(*str), ast_str_size(*str) - 1);
  93                 if (size == AST_PJSIP_XML_PROLOG_LEN) {
  94                         ast_str_make_space(str, ast_str_size(*str) * 2);
  95                         ++growths;
  96                 }
  97         } while (size == AST_PJSIP_XML_PROLOG_LEN && growths < MAX_STRING_GROWTHS);
  98
  99         if (size == AST_PJSIP_XML_PROLOG_LEN) {
 100                 ast_log(LOG_WARNING, "PIDF body text too large\n");
 101                 return;
 102         }
 103
 104         *(ast_str_buffer(*str) + size) = '\0';
 105         ast_str_update(*str);
 106 }
 107
 108 static struct ast_sip_pubsub_body_generator pidf_body_generator = {
 109         .type = "application",
 110         .subtype = "pidf+xml",
 111         .allocate_body = pidf_allocate_body,
 112         .generate_body_content = pidf_generate_body_content,
 113         .to_string = pidf_to_string,
 114         /* No need for a destroy_body callback since we use a pool */
 115 };
 116
 117 static int load_module(void)
 118 {
 119         if (ast_sip_pubsub_register_body_generator(&pidf_body_generator)) {
 120                 return AST_MODULE_LOAD_DECLINE;
 121         }
 122         return AST_MODULE_LOAD_SUCCESS;
 123 }
 124
 125 static int unload_module(void)
 126 {
 127         ast_sip_pubsub_unregister_body_generator(&pidf_body_generator);
 128         return 0;
 129 }
 130
 131 AST_MODULE_INFO(ASTERISK_GPL_KEY, AST_MODFLAG_LOAD_ORDER, "PJSIP Extension State PIDF Provider",
 132                 .support_level = AST_MODULE_SUPPORT_CORE,
 133                 .load = load_module,
 134                 .unload = unload_module,
 135                 .load_pri = AST_MODPRI_CHANNEL_DEPEND,
 136 );