funcs/func_curl.c

   1 /*
   2  * Asterisk -- An open source telephony toolkit.
   3  *
   4  * Copyright (C)  2004 - 2006, Tilghman Lesher
   5  *
   6  * Tilghman Lesher <curl-20050919@the-tilghman.com>
   7  * and Brian Wilkins <bwilkins@cfl.rr.com> (Added POST option)
   8  *
   9  * app_curl.c is distributed with no restrictions on usage or
  10  * redistribution.
  11  *
  12  * See http://www.asterisk.org for more information about
  13  * the Asterisk project. Please do not directly contact
  14  * any of the maintainers of this project for assistance;
  15  * the project provides a web site, mailing lists and IRC
  16  * channels for your use.
  17  *
  18  */
  19
  20 /*! \file
  21  *
  22  * \brief Curl - Load a URL
  23  *
  24  * \author Tilghman Lesher <curl-20050919@the-tilghman.com>
  25  *
  26  * \note Brian Wilkins <bwilkins@cfl.rr.com> (Added POST option)
  27  *
  28  * \ingroup functions
  29  */
  30
  31 /*** MODULEINFO
  32         <depend>curl</depend>
  33  ***/
  34
  35 #include "asterisk.h"
  36
  37 ASTERISK_FILE_VERSION(__FILE__, "$Revision$")
  38
  39 #include <stdio.h>
  40 #include <stdlib.h>
  41 #include <string.h>
  42 #include <curl/curl.h>
  43
  44 #include "asterisk/lock.h"
  45 #include "asterisk/file.h"
  46 #include "asterisk/logger.h"
  47 #include "asterisk/channel.h"
  48 #include "asterisk/pbx.h"
  49 #include "asterisk/cli.h"
  50 #include "asterisk/options.h"
  51 #include "asterisk/module.h"
  52 #include "asterisk/app.h"
  53 #include "asterisk/utils.h"
  54 #include "asterisk/threadstorage.h"
  55
  56 struct MemoryStruct {
  57         char *memory;
  58         size_t size;
  59 };
  60
  61 static void *myrealloc(void *ptr, size_t size)
  62 {
  63         /* There might be a realloc() out there that doesn't like reallocing
  64            NULL pointers, so we take care of it here */
  65         if (ptr)
  66                 return ast_realloc(ptr, size);
  67         else
  68                 return ast_malloc(size);
  69 }
  70
  71 static size_t WriteMemoryCallback(void *ptr, size_t size, size_t nmemb, void *data)
  72 {
  73         register int realsize = size * nmemb;
  74         struct MemoryStruct *mem = (struct MemoryStruct *)data;
  75
  76         mem->memory = (char *)myrealloc(mem->memory, mem->size + realsize + 1);
  77         if (mem->memory) {
  78                 memcpy(&(mem->memory[mem->size]), ptr, realsize);
  79                 mem->size += realsize;
  80                 mem->memory[mem->size] = 0;
  81         }
  82         return realsize;
  83 }
  84
  85 static const char *global_useragent = "asterisk-libcurl-agent/1.0";
  86
  87 static void curl_instance_cleanup(void *data)
  88 {
  89         CURL **curl = data;
  90
  91         curl_easy_cleanup(*curl);
  92 }
  93
  94 AST_THREADSTORAGE_CUSTOM(curl_instance, curl_instance_init, curl_instance_cleanup);
  95
  96 static int curl_internal(struct MemoryStruct *chunk, char *url, char *post)
  97 {
  98         CURL **curl;
  99
 100         if (!(curl = ast_threadstorage_get(&curl_instance, sizeof(*curl))))
 101                 return -1;
 102
 103         if (!*curl) {
 104                 if (!(*curl = curl_easy_init()))
 105                         return -1;
 106                 curl_easy_setopt(*curl, CURLOPT_NOSIGNAL, 1);
 107                 curl_easy_setopt(*curl, CURLOPT_TIMEOUT, 180);
 108                 curl_easy_setopt(*curl, CURLOPT_WRITEFUNCTION, WriteMemoryCallback);
 109                 curl_easy_setopt(*curl, CURLOPT_USERAGENT, global_useragent);
 110         }
 111
 112         curl_easy_setopt(*curl, CURLOPT_URL, url);
 113         curl_easy_setopt(*curl, CURLOPT_WRITEDATA, (void *) chunk);
 114
 115         if (post) {
 116                 curl_easy_setopt(*curl, CURLOPT_POST, 1);
 117                 curl_easy_setopt(*curl, CURLOPT_POSTFIELDS, post);
 118         }
 119
 120         curl_easy_perform(*curl);
 121
 122         if (post)
 123                 curl_easy_setopt(*curl, CURLOPT_POST, 0);
 124
 125         return 0;
 126 }
 127
 128 static int acf_curl_exec(struct ast_channel *chan, char *cmd, char *info, char *buf, size_t len)
 129 {
 130         struct ast_module_user *u;
 131         struct MemoryStruct chunk = { NULL, 0 };
 132         AST_DECLARE_APP_ARGS(args,
 133                 AST_APP_ARG(url);
 134                 AST_APP_ARG(postdata);
 135         );
 136
 137         *buf = '\0';
 138
 139         if (ast_strlen_zero(info)) {
 140                 ast_log(LOG_WARNING, "CURL requires an argument (URL)\n");
 141                 return -1;
 142         }
 143
 144         u = ast_module_user_add(chan);
 145
 146         AST_STANDARD_APP_ARGS(args, info);
 147
 148         ast_autoservice_start(chan);
 149
 150         if (!curl_internal(&chunk, args.url, args.postdata)) {
 151                 if (chunk.memory) {
 152                         chunk.memory[chunk.size] = '\0';
 153                         if (chunk.memory[chunk.size - 1] == 10)
 154                                 chunk.memory[chunk.size - 1] = '\0';
 155
 156                         ast_copy_string(buf, chunk.memory, len);
 157                         free(chunk.memory);
 158                 }
 159         } else {
 160                 ast_log(LOG_ERROR, "Cannot allocate curl structure\n");
 161         }
 162
 163         ast_autoservice_stop(chan);
 164
 165         ast_module_user_remove(u);
 166
 167         return 0;
 168 }
 169
 170 struct ast_custom_function acf_curl = {
 171         .name = "CURL",
 172         .synopsis = "Retrieves the contents of a URL",
 173         .syntax = "CURL(url[|post-data])",
 174         .desc =
 175         "  url       - URL to retrieve\n"
 176         "  post-data - Optional data to send as a POST (GET is default action)\n",
 177         .read = acf_curl_exec,
 178 };
 179
 180 static int unload_module(void)
 181 {
 182         int res;
 183
 184         res = ast_custom_function_unregister(&acf_curl);
 185
 186         ast_module_user_hangup_all();
 187
 188         curl_global_cleanup();
 189
 190         return res;
 191 }
 192
 193 static int load_module(void)
 194 {
 195         int res;
 196
 197         if (curl_global_init(CURL_GLOBAL_ALL)) {
 198                 ast_log(LOG_ERROR, "Unable to initialize the CURL library. Cannot load func_curl\n");
 199                 return AST_MODULE_LOAD_DECLINE;
 200         }
 201
 202         res = ast_custom_function_register(&acf_curl);
 203
 204         return res;
 205 }
 206
 207 AST_MODULE_INFO_STANDARD(ASTERISK_GPL_KEY, "Load external URL");
 208