apps/app_directed_pickup.c

   1 /*
   2  * Asterisk -- An open source telephony toolkit.
   3  *
   4  * Copyright (C) 2005, Joshua Colp
   5  *
   6  * Joshua Colp <jcolp@digium.com>
   7  *
   8  * Portions merged from app_pickupchan, which was
   9  * Copyright (C) 2008, Gary Cook
  10  *
  11  * See http://www.asterisk.org for more information about
  12  * the Asterisk project. Please do not directly contact
  13  * any of the maintainers of this project for assistance;
  14  * the project provides a web site, mailing lists and IRC
  15  * channels for your use.
  16  *
  17  * This program is free software, distributed under the terms of
  18  * the GNU General Public License Version 2. See the LICENSE file
  19  * at the top of the source tree.
  20  */
  21
  22 /*! \file
  23  *
  24  * \brief Directed Call Pickup Support
  25  *
  26  * \author Joshua Colp <jcolp@digium.com>
  27  * \author Gary Cook
  28  *
  29  * \ingroup applications
  30  */
  31
  32 /*** MODULEINFO
  33         <support_level>core</support_level>
  34  ***/
  35
  36 #include "asterisk.h"
  37
  38 ASTERISK_FILE_VERSION(__FILE__, "$Revision$")
  39
  40 #include "asterisk/file.h"
  41 #include "asterisk/channel.h"
  42 #include "asterisk/pbx.h"
  43 #include "asterisk/module.h"
  44 #include "asterisk/lock.h"
  45 #include "asterisk/app.h"
  46 #include "asterisk/pickup.h"
  47 #include "asterisk/manager.h"
  48 #include "asterisk/callerid.h"
  49
  50 #define PICKUPMARK "PICKUPMARK"
  51
  52 /*** DOCUMENTATION
  53         <application name="Pickup" language="en_US">
  54                 <synopsis>
  55                         Directed extension call pickup.
  56                 </synopsis>
  57                 <syntax>
  58                         <parameter name="targets" argsep="&amp;">
  59                                 <argument name="extension" argsep="@" required="true">
  60                                         <para>Specification of the pickup target.</para>
  61                                         <argument name="extension" required="true"/>
  62                                         <argument name="context" />
  63                                 </argument>
  64                                 <argument name="extension2" argsep="@" multiple="true">
  65                                         <para>Additional specifications of pickup targets.</para>
  66                                         <argument name="extension2" required="true"/>
  67                                         <argument name="context2"/>
  68                                 </argument>
  69                         </parameter>
  70                 </syntax>
  71                 <description>
  72                         <para>This application can pickup a specified ringing channel.  The channel
  73                         to pickup can be specified in the following ways.</para>
  74                         <para>1) If no <replaceable>extension</replaceable> targets are specified,
  75                         the application will pickup a channel matching the pickup group of the
  76                         requesting channel.</para>
  77                         <para>2) If the <replaceable>extension</replaceable> is specified with a
  78                         <replaceable>context</replaceable> of the special string
  79                         <literal>PICKUPMARK</literal> (for example 10@PICKUPMARK), the application
  80                         will pickup a channel which has defined the channel variable
  81                         <variable>PICKUPMARK</variable> with the same value as
  82                         <replaceable>extension</replaceable> (in this example,
  83                         <literal>10</literal>).</para>
  84                         <para>3) If the <replaceable>extension</replaceable> is specified
  85                         with or without a <replaceable>context</replaceable>, the channel with a
  86                         matching <replaceable>extension</replaceable> and <replaceable>context</replaceable>
  87                         will be picked up.  If no <replaceable>context</replaceable> is specified,
  88                         the current context will be used.</para>
  89                         <note><para>The <replaceable>extension</replaceable> is typically set on
  90                         matching channels by the dial application that created the channel.  The
  91                         <replaceable>context</replaceable> is set on matching channels by the
  92                         channel driver for the device.</para></note>
  93                 </description>
  94         </application>
  95         <application name="PickupChan" language="en_US">
  96                 <synopsis>
  97                         Pickup a ringing channel.
  98                 </synopsis>
  99                 <syntax >
 100                         <parameter name="Technology/Resource" argsep="&amp;" required="true">
 101                                 <argument name="Technology/Resource" required="true" />
 102                                 <argument name="Technology2/Resource2" required="false" multiple="true" />
 103                         </parameter>
 104                         <parameter name="options" required="false">
 105                                 <optionlist>
 106                                         <option name="p">
 107                                                 <para>Channel name specified partial name. Used when find channel by callid.</para>
 108                                         </option>
 109                                 </optionlist>
 110                         </parameter>
 111                 </syntax>
 112                 <description>
 113                         <para>This will pickup a specified <replaceable>channel</replaceable> if ringing.</para>
 114                 </description>
 115         </application>
 116  ***/
 117
 118 static const char app[] = "Pickup";
 119 static const char app2[] = "PickupChan";
 120
 121 struct pickup_by_name_args {
 122         const char *name;
 123         size_t len;
 124 };
 125
 126 static int pickup_by_name_cb(void *obj, void *arg, void *data, int flags)
 127 {
 128         struct ast_channel *target = obj;/*!< Potential pickup target */
 129         struct pickup_by_name_args *args = data;
 130
 131         ast_channel_lock(target);
 132         if (!strncasecmp(ast_channel_name(target), args->name, args->len) && ast_can_pickup(target)) {
 133                 /* Return with the channel still locked on purpose */
 134                 return CMP_MATCH | CMP_STOP;
 135         }
 136         ast_channel_unlock(target);
 137
 138         return 0;
 139 }
 140
 141 /*! \brief Helper Function to walk through ALL channels checking NAME and STATE */
 142 static struct ast_channel *my_ast_get_channel_by_name_locked(const char *channame)
 143 {
 144         char *chkchan;
 145         struct pickup_by_name_args pickup_args;
 146
 147         /* Check if channel name contains a '-'.
 148          * In this case the channel name will be interpreted as full channel name.
 149          */
 150         if (strchr(channame, '-')) {
 151                 /* check full channel name */
 152                 pickup_args.len = strlen(channame);
 153                 pickup_args.name = channame;
 154         } else {
 155                 /* need to append a '-' for the comparison so we check full channel name,
 156                  * i.e SIP/hgc- , use a temporary variable so original stays the same for
 157                  * debugging.
 158                  */
 159                 pickup_args.len = strlen(channame) + 1;
 160                 chkchan = ast_alloca(pickup_args.len + 1);
 161                 strcpy(chkchan, channame);
 162                 strcat(chkchan, "-");
 163                 pickup_args.name = chkchan;
 164         }
 165
 166         return ast_channel_callback(pickup_by_name_cb, NULL, &pickup_args, 0);
 167 }
 168
 169 /*! \brief Attempt to pick up named channel, does not use context */
 170 static int pickup_by_channel(struct ast_channel *chan, char *pickup)
 171 {
 172         int res = -1;
 173         struct ast_channel *target;/*!< Potential pickup target */
 174
 175         target = my_ast_get_channel_by_name_locked(pickup);
 176         if (target) {
 177                 /* Just check that we are not picking up the SAME as target. (i.e. ourself) */
 178                 if (chan != target) {
 179                         res = ast_do_pickup(chan, target);
 180                 }
 181                 ast_channel_unlock(target);
 182                 target = ast_channel_unref(target);
 183         }
 184
 185         return res;
 186 }
 187
 188 /* Attempt to pick up specified extension with context */
 189 static int pickup_by_exten(struct ast_channel *chan, const char *exten, const char *context)
 190 {
 191         struct ast_channel *target = NULL;/*!< Potential pickup target */
 192         struct ast_channel_iterator *iter;
 193         int res = -1;
 194
 195         if (!(iter = ast_channel_iterator_by_exten_new(exten, context))) {
 196                 return -1;
 197         }
 198
 199         while ((target = ast_channel_iterator_next(iter))) {
 200                 ast_channel_lock(target);
 201                 if ((chan != target) && ast_can_pickup(target)) {
 202                         ast_log(LOG_NOTICE, "%s pickup by %s\n", ast_channel_name(target), ast_channel_name(chan));
 203                         break;
 204                 }
 205                 ast_channel_unlock(target);
 206                 target = ast_channel_unref(target);
 207         }
 208
 209         ast_channel_iterator_destroy(iter);
 210
 211         if (target) {
 212                 res = ast_do_pickup(chan, target);
 213                 ast_channel_unlock(target);
 214                 target = ast_channel_unref(target);
 215         }
 216
 217         return res;
 218 }
 219
 220 static int find_by_mark(void *obj, void *arg, void *data, int flags)
 221 {
 222         struct ast_channel *target = obj;/*!< Potential pickup target */
 223         struct ast_channel *chan = arg;
 224         const char *mark = data;
 225         const char *tmp;
 226
 227         if (chan == target) {
 228                 /* The channel attempting to pickup a call cannot pickup itself. */
 229                 return 0;
 230         }
 231
 232         ast_channel_lock(target);
 233         tmp = pbx_builtin_getvar_helper(target, PICKUPMARK);
 234         if (tmp && !strcasecmp(tmp, mark) && ast_can_pickup(target)) {
 235                 /* Return with the channel still locked on purpose */
 236                 return CMP_MATCH | CMP_STOP;
 237         }
 238         ast_channel_unlock(target);
 239
 240         return 0;
 241 }
 242
 243 /* Attempt to pick up specified mark */
 244 static int pickup_by_mark(struct ast_channel *chan, const char *mark)
 245 {
 246         struct ast_channel *target;/*!< Potential pickup target */
 247         int res = -1;
 248
 249         /* The found channel is already locked. */
 250         target = ast_channel_callback(find_by_mark, chan, (char *) mark, 0);
 251         if (target) {
 252                 res = ast_do_pickup(chan, target);
 253                 ast_channel_unlock(target);
 254                 target = ast_channel_unref(target);
 255         }
 256
 257         return res;
 258 }
 259
 260 static int pickup_by_group(struct ast_channel *chan)
 261 {
 262         struct ast_channel *target;/*!< Potential pickup target */
 263         int res = -1;
 264
 265         /* The found channel is already locked. */
 266         target = ast_pickup_find_by_group(chan);
 267         if (target) {
 268                 ast_log(LOG_NOTICE, "pickup %s attempt by %s\n", ast_channel_name(target), ast_channel_name(chan));
 269                 res = ast_do_pickup(chan, target);
 270                 ast_channel_unlock(target);
 271                 target = ast_channel_unref(target);
 272         }
 273
 274         return res;
 275 }
 276
 277 /* application entry point for Pickup() */
 278 static int pickup_exec(struct ast_channel *chan, const char *data)
 279 {
 280         char *tmp;
 281         char *exten;
 282         char *context;
 283
 284         if (ast_strlen_zero(data)) {
 285                 return pickup_by_group(chan) ? 0 : -1;
 286         }
 287
 288         /* Parse extension (and context if there) */
 289         tmp = ast_strdupa(data);
 290         while (!ast_strlen_zero(tmp) && (exten = strsep(&tmp, "&"))) {
 291                 if ((context = strchr(exten, '@')))
 292                         *context++ = '\0';
 293                 if (!ast_strlen_zero(context) && !strcasecmp(context, PICKUPMARK)) {
 294                         if (!pickup_by_mark(chan, exten)) {
 295                                 /* Pickup successful.  Stop the dialplan this channel is a zombie. */
 296                                 return -1;
 297                         }
 298                 } else {
 299                         if (ast_strlen_zero(context)) {
 300                                 context = (char *) ast_channel_context(chan);
 301                         }
 302                         if (!pickup_by_exten(chan, exten, context)) {
 303                                 /* Pickup successful.  Stop the dialplan this channel is a zombie. */
 304                                 return -1;
 305                         }
 306                 }
 307                 ast_log(LOG_NOTICE, "No target channel found for %s@%s.\n", exten, context);
 308         }
 309
 310         /* Pickup failed.  Keep going in the dialplan. */
 311         return 0;
 312 }
 313
 314 /* Find channel for pick up specified by partial channel name */
 315 static int find_by_part(void *obj, void *arg, void *data, int flags)
 316 {
 317         struct ast_channel *target = obj;/*!< Potential pickup target */
 318         const char *part = data;
 319         int len = strlen(part);
 320
 321         ast_channel_lock(target);
 322         if (len <= strlen(ast_channel_name(target)) && !strncmp(ast_channel_name(target), part, len)
 323                 && ast_can_pickup(target)) {
 324                 /* Return with the channel still locked on purpose */
 325                 return CMP_MATCH | CMP_STOP;
 326         }
 327         ast_channel_unlock(target);
 328
 329         return 0;
 330 }
 331
 332 /* Attempt to pick up specified by partial channel name */
 333 static int pickup_by_part(struct ast_channel *chan, const char *part)
 334 {
 335         struct ast_channel *target;/*!< Potential pickup target */
 336         int res = -1;
 337
 338         /* The found channel is already locked. */
 339         target = ast_channel_callback(find_by_part, NULL, (char *) part, 0);
 340         if (target) {
 341                 res = ast_do_pickup(chan, target);
 342                 ast_channel_unlock(target);
 343                 target = ast_channel_unref(target);
 344         }
 345
 346         return res;
 347 }
 348
 349 /* application entry point for PickupChan() */
 350 static int pickupchan_exec(struct ast_channel *chan, const char *data)
 351 {
 352         int partial_pickup = 0;
 353         char *pickup = NULL;
 354         char *parse = ast_strdupa(data);
 355         AST_DECLARE_APP_ARGS(args,
 356                 AST_APP_ARG(channel);
 357                 AST_APP_ARG(options);
 358         );
 359         AST_STANDARD_APP_ARGS(args, parse);
 360
 361         if (ast_strlen_zero(args.channel)) {
 362                 ast_log(LOG_WARNING, "PickupChan requires an argument (channel)!\n");
 363                 /* Pickup failed.  Keep going in the dialplan. */
 364                 return 0;
 365         }
 366
 367         if (!ast_strlen_zero(args.options) && strchr(args.options, 'p')) {
 368                 partial_pickup = 1;
 369         }
 370
 371         /* Parse channel */
 372         while (!ast_strlen_zero(args.channel) && (pickup = strsep(&args.channel, "&"))) {
 373                 if (!strncasecmp(ast_channel_name(chan), pickup, strlen(pickup))) {
 374                         ast_log(LOG_NOTICE, "Cannot pickup your own channel %s.\n", pickup);
 375                 } else {
 376                         if (partial_pickup) {
 377                                 if (!pickup_by_part(chan, pickup)) {
 378                                         /* Pickup successful.  Stop the dialplan this channel is a zombie. */
 379                                         return -1;
 380                                 }
 381                         } else if (!pickup_by_channel(chan, pickup)) {
 382                                 /* Pickup successful.  Stop the dialplan this channel is a zombie. */
 383                                 return -1;
 384                         }
 385                         ast_log(LOG_NOTICE, "No target channel found for %s.\n", pickup);
 386                 }
 387         }
 388
 389         /* Pickup failed.  Keep going in the dialplan. */
 390         return 0;
 391 }
 392
 393 static int unload_module(void)
 394 {
 395         int res;
 396
 397         res = ast_unregister_application(app);
 398         res |= ast_unregister_application(app2);
 399
 400         return res;
 401 }
 402
 403 static int load_module(void)
 404 {
 405         int res;
 406
 407         res = ast_register_application_xml(app, pickup_exec);
 408         res |= ast_register_application_xml(app2, pickupchan_exec);
 409
 410         return res;
 411 }
 412
 413 AST_MODULE_INFO_STANDARD(ASTERISK_GPL_KEY, "Directed Call Pickup Application");