Sat Nov 1 06:28:23 2008

Asterisk developer's documentation

---

chan_agent.c

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/*
 * Asterisk -- An open source telephony toolkit.
 *
 * Copyright (C) 1999 - 2006, Digium, Inc.
 *
 * Mark Spencer <markster@digium.com>
 *
 * See http://www.asterisk.org for more information about
 * the Asterisk project. Please do not directly contact
 * any of the maintainers of this project for assistance;
 * the project provides a web site, mailing lists and IRC
 * channels for your use.
 *
 * This program is free software, distributed under the terms of
 * the GNU General Public License Version 2. See the LICENSE file
 * at the top of the source tree.
 */


/*! \file
 * 
 * \brief Implementation of Agents (proxy channel)
 *
 * \author Mark Spencer <markster@digium.com>
 *
 * This file is the implementation of Agents modules.
 * It is a dynamic module that is loaded by Asterisk. 
 * \par See also
 * \arg \ref Config_agent
 *
 * \ingroup channel_drivers
 */
/*** MODULEINFO
        <depend>chan_local</depend>
 ***/

#include "asterisk.h"

ASTERISK_FILE_VERSION(__FILE__, "$Revision: 141366 $")

#include <stdio.h>
#include <string.h>
#include <errno.h>
#include <unistd.h>
#include <sys/socket.h>
#include <stdlib.h>
#include <fcntl.h>
#include <netdb.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <sys/signal.h>

#include "asterisk/lock.h"
#include "asterisk/channel.h"
#include "asterisk/config.h"
#include "asterisk/logger.h"
#include "asterisk/module.h"
#include "asterisk/pbx.h"
#include "asterisk/options.h"
#include "asterisk/lock.h"
#include "asterisk/sched.h"
#include "asterisk/io.h"
#include "asterisk/rtp.h"
#include "asterisk/acl.h"
#include "asterisk/callerid.h"
#include "asterisk/file.h"
#include "asterisk/cli.h"
#include "asterisk/app.h"
#include "asterisk/musiconhold.h"
#include "asterisk/manager.h"
#include "asterisk/features.h"
#include "asterisk/utils.h"
#include "asterisk/causes.h"
#include "asterisk/astdb.h"
#include "asterisk/devicestate.h"
#include "asterisk/monitor.h"
#include "asterisk/stringfields.h"

static const char tdesc[] = "Call Agent Proxy Channel";
static const char config[] = "agents.conf";

static const char app[] = "AgentLogin";
static const char app2[] = "AgentCallbackLogin";
static const char app3[] = "AgentMonitorOutgoing";

static const char synopsis[] = "Call agent login";
static const char synopsis2[] = "Call agent callback login";
static const char synopsis3[] = "Record agent's outgoing call";

static const char descrip[] =
"  AgentLogin([AgentNo][|options]):\n"
"Asks the agent to login to the system.  Always returns -1.  While\n"
"logged in, the agent can receive calls and will hear a 'beep'\n"
"when a new call comes in. The agent can dump the call by pressing\n"
"the star key.\n"
"The option string may contain zero or more of the following characters:\n"
"      's' -- silent login - do not announce the login ok segment after agent logged in/off\n";

static const char descrip2[] =
"  AgentCallbackLogin([AgentNo][|[options][|[exten]@context]]):\n"
"Asks the agent to login to the system with callback.\n"
"The agent's callback extension is called (optionally with the specified\n"
"context).\n"
"The option string may contain zero or more of the following characters:\n"
"      's' -- silent login - do not announce the login ok segment agent logged in/off\n";

static const char descrip3[] =
"  AgentMonitorOutgoing([options]):\n"
"Tries to figure out the id of the agent who is placing outgoing call based on\n"
"comparison of the callerid of the current interface and the global variable \n"
"placed by the AgentCallbackLogin application. That's why it should be used only\n"
"with the AgentCallbackLogin app. Uses the monitoring functions in chan_agent \n"
"instead of Monitor application. That have to be configured in the agents.conf file.\n"
"\nReturn value:\n"
"Normally the app returns 0 unless the options are passed. Also if the callerid or\n"
"the agentid are not specified it'll look for n+101 priority.\n"
"\nOptions:\n"
"  'd' - make the app return -1 if there is an error condition and there is\n"
"        no extension n+101\n"
"  'c' - change the CDR so that the source of the call is 'Agent/agent_id'\n"
"  'n' - don't generate the warnings when there is no callerid or the\n"
"        agentid is not known.\n"
"             It's handy if you want to have one context for agent and non-agent calls.\n";

static const char mandescr_agents[] =
"Description: Will list info about all possible agents.\n"
"Variables: NONE\n";

static const char mandescr_agent_logoff[] =
"Description: Sets an agent as no longer logged in.\n"
"Variables: (Names marked with * are required)\n"
"  *Agent: Agent ID of the agent to log off\n"
"  Soft: Set to 'true' to not hangup existing calls\n";

static const char mandescr_agent_callback_login[] =
"Description: Sets an agent as logged in with callback.\n"
"Variables: (Names marked with * are required)\n"
"  *Agent: Agent ID of the agent to login\n"
"  *Exten: Extension to use for callback\n"
"  Context: Context to use for callback\n"
"  AckCall: Set to 'true' to require an acknowledgement by '#' when agent is called back\n"
"  WrapupTime: the minimum amount of time after disconnecting before the caller can receive a new call\n";

static char moh[80] = "default";

#define AST_MAX_AGENT   80                          /*!< Agent ID or Password max length */
#define AST_MAX_BUF  256
#define AST_MAX_FILENAME_LEN  256

static const char pa_family[] = "Agents";          /*!< Persistent Agents astdb family */
#define PA_MAX_LEN 2048                             /*!< The maximum length of each persistent member agent database entry */

static int persistent_agents = 0;                   /*!< queues.conf [general] option */
static void dump_agents(void);

static ast_group_t group;
static int autologoff;
static int wrapuptime;
static int ackcall;
static int endcall;
static int multiplelogin = 1;
static int autologoffunavail = 0;

static int maxlogintries = 3;
static char agentgoodbye[AST_MAX_FILENAME_LEN] = "vm-goodbye";

static int recordagentcalls = 0;
static char recordformat[AST_MAX_BUF] = "";
static char recordformatext[AST_MAX_BUF] = "";
static char urlprefix[AST_MAX_BUF] = "";
static char savecallsin[AST_MAX_BUF] = "";
static int updatecdr = 0;
static char beep[AST_MAX_BUF] = "beep";

#define GETAGENTBYCALLERID "AGENTBYCALLERID"

/*! \brief Structure representing an agent.  */
struct agent_pvt {
   ast_mutex_t lock;              /*!< Channel private lock */
   int dead;                      /*!< Poised for destruction? */
   int pending;                   /*!< Not a real agent -- just pending a match */
   int abouttograb;               /*!< About to grab */
   int autologoff;                /*!< Auto timeout time */
   int ackcall;                   /*!< ackcall */
   int deferlogoff;               /*!< Defer logoff to hangup */
   time_t loginstart;             /*!< When agent first logged in (0 when logged off) */
   time_t start;                  /*!< When call started */
   struct timeval lastdisc;       /*!< When last disconnected */
   int wrapuptime;                /*!< Wrapup time in ms */
   ast_group_t group;             /*!< Group memberships */
   int acknowledged;              /*!< Acknowledged */
   char moh[80];                  /*!< Which music on hold */
   char agent[AST_MAX_AGENT];     /*!< Agent ID */
   char password[AST_MAX_AGENT];  /*!< Password for Agent login */
   char name[AST_MAX_AGENT];
   int inherited_devicestate;     /*!< Does the underlying channel have a devicestate to pass? */
   ast_mutex_t app_lock;          /**< Synchronization between owning applications */
   volatile pthread_t owning_app; /**< Owning application thread id */
   volatile int app_sleep_cond;   /**< Sleep condition for the login app */
   struct ast_channel *owner;     /**< Agent */
   char loginchan[80];            /**< channel they logged in from */
   char logincallerid[80];        /**< Caller ID they had when they logged in */
   struct ast_channel *chan;      /**< Channel we use */
   AST_LIST_ENTRY(agent_pvt) list;  /**< Next Agent in the linked list. */
};

static AST_LIST_HEAD_STATIC(agents, agent_pvt); /*!< Holds the list of agents (loaded form agents.conf). */

#define CHECK_FORMATS(ast, p) do { \
   if (p->chan) {\
      if (ast->nativeformats != p->chan->nativeformats) { \
         ast_log(LOG_DEBUG, "Native formats changing from %d to %d\n", ast->nativeformats, p->chan->nativeformats); \
         /* Native formats changed, reset things */ \
         ast->nativeformats = p->chan->nativeformats; \
         ast_log(LOG_DEBUG, "Resetting read to %d and write to %d\n", ast->readformat, ast->writeformat);\
         ast_set_read_format(ast, ast->readformat); \
         ast_set_write_format(ast, ast->writeformat); \
      } \
      if (p->chan->readformat != ast->rawreadformat && !p->chan->generator)  \
         ast_set_read_format(p->chan, ast->rawreadformat); \
      if (p->chan->writeformat != ast->rawwriteformat && !p->chan->generator) \
         ast_set_write_format(p->chan, ast->rawwriteformat); \
   } \
} while(0)

/*! \brief Cleanup moves all the relevant FD's from the 2nd to the first, but retains things
   properly for a timingfd XXX This might need more work if agents were logged in as agents or other
   totally impractical combinations XXX */

#define CLEANUP(ast, p) do { \
   int x; \
   if (p->chan) { \
      for (x=0;x<AST_MAX_FDS;x++) {\
         if (x != AST_TIMING_FD) \
            ast->fds[x] = p->chan->fds[x]; \
      } \
      ast->fds[AST_AGENT_FD] = p->chan->fds[AST_TIMING_FD]; \
   } \
} while(0)

/*--- Forward declarations */
static struct ast_channel *agent_request(const char *type, int format, void *data, int *cause);
static int agent_devicestate(void *data);
static void agent_logoff_maintenance(struct agent_pvt *p, char *loginchan, long logintime, const char *uniqueid, char *logcommand);
static int agent_digit_begin(struct ast_channel *ast, char digit);
static int agent_digit_end(struct ast_channel *ast, char digit, unsigned int duration);
static int agent_call(struct ast_channel *ast, char *dest, int timeout);
static int agent_hangup(struct ast_channel *ast);
static int agent_answer(struct ast_channel *ast);
static struct ast_frame *agent_read(struct ast_channel *ast);
static int agent_write(struct ast_channel *ast, struct ast_frame *f);
static int agent_sendhtml(struct ast_channel *ast, int subclass, const char *data, int datalen);
static int agent_sendtext(struct ast_channel *ast, const char *text);
static int agent_indicate(struct ast_channel *ast, int condition, const void *data, size_t datalen);
static int agent_fixup(struct ast_channel *oldchan, struct ast_channel *newchan);
static struct ast_channel *agent_bridgedchannel(struct ast_channel *chan, struct ast_channel *bridge);
static void set_agentbycallerid(const char *callerid, const char *agent);
static struct ast_channel* agent_get_base_channel(struct ast_channel *chan);
static int agent_set_base_channel(struct ast_channel *chan, struct ast_channel *base);

/*! \brief Channel interface description for PBX integration */
static const struct ast_channel_tech agent_tech = {
   .type = "Agent",
   .description = tdesc,
   .capabilities = -1,
   .requester = agent_request,
   .devicestate = agent_devicestate,
   .send_digit_begin = agent_digit_begin,
   .send_digit_end = agent_digit_end,
   .call = agent_call,
   .hangup = agent_hangup,
   .answer = agent_answer,
   .read = agent_read,
   .write = agent_write,
   .write_video = agent_write,
   .send_html = agent_sendhtml,
   .send_text = agent_sendtext,
   .exception = agent_read,
   .indicate = agent_indicate,
   .fixup = agent_fixup,
   .bridged_channel = agent_bridgedchannel,
   .get_base_channel = agent_get_base_channel,
   .set_base_channel = agent_set_base_channel,
};

static int agent_devicestate_cb(const char *dev, int state, void *data)
{
   int res, i;
   struct agent_pvt *p;
   char basename[AST_CHANNEL_NAME], *tmp;

   /* Skip Agent status */
   if (!strncasecmp(dev, "Agent/", 6)) {
      return 0;
   }

   /* Try to be safe, but don't deadlock */
   for (i = 0; i < 10; i++) {
      if ((res = AST_LIST_TRYLOCK(&agents)) == 0) {
         break;
      }
   }
   if (res) {
      return -1;
   }

   AST_LIST_TRAVERSE(&agents, p, list) {
      ast_mutex_lock(&p->lock);
      if (p->chan) {
         ast_copy_string(basename, p->chan->name, sizeof(basename));
         if ((tmp = strrchr(basename, '-'))) {
            *tmp = '\0';
         }
         if (strcasecmp(p->chan->name, dev) == 0 || strcasecmp(basename, dev) == 0) {
            p->inherited_devicestate = state;
            ast_device_state_changed("Agent/%s", p->agent);
         }
      }
      ast_mutex_unlock(&p->lock);
   }
   AST_LIST_UNLOCK(&agents);
   return 0;
}

/*!
 * Adds an agent to the global list of agents.
 *
 * \param agent A string with the username, password and real name of an agent. As defined in agents.conf. Example: "13,169,John Smith"
 * \param pending If it is pending or not.
 * @return The just created agent.
 * \sa agent_pvt, agents.
 */
static struct agent_pvt *add_agent(char *agent, int pending)
{
   char *parse;
   AST_DECLARE_APP_ARGS(args,
      AST_APP_ARG(agt);
      AST_APP_ARG(password);
      AST_APP_ARG(name);
   );
   char *password = NULL;
   char *name = NULL;
   char *agt = NULL;
   struct agent_pvt *p;

   parse = ast_strdupa(agent);

   /* Extract username (agt), password and name from agent (args). */
   AST_NONSTANDARD_APP_ARGS(args, parse, ',');

   if(args.argc == 0) {
      ast_log(LOG_WARNING, "A blank agent line!\n");
      return NULL;
   }

   if(ast_strlen_zero(args.agt) ) {
      ast_log(LOG_WARNING, "An agent line with no agentid!\n");
      return NULL;
   } else
      agt = args.agt;

   if(!ast_strlen_zero(args.password)) {
      password = args.password;
      while (*password && *password < 33) password++;
   }
   if(!ast_strlen_zero(args.name)) {
      name = args.name;
      while (*name && *name < 33) name++;
   }
   
   /* Are we searching for the agent here ? To see if it exists already ? */
   AST_LIST_TRAVERSE(&agents, p, list) {
      if (!pending && !strcmp(p->agent, agt))
         break;
   }
   if (!p) {
      // Build the agent.
      if (!(p = ast_calloc(1, sizeof(*p))))
         return NULL;
      ast_copy_string(p->agent, agt, sizeof(p->agent));
      ast_mutex_init(&p->lock);
      ast_mutex_init(&p->app_lock);
      p->owning_app = (pthread_t) -1;
      p->app_sleep_cond = 1;
      p->group = group;
      p->pending = pending;
      p->inherited_devicestate = -1;
      AST_LIST_INSERT_TAIL(&agents, p, list);
   }
   
   ast_copy_string(p->password, password ? password : "", sizeof(p->password));
   ast_copy_string(p->name, name ? name : "", sizeof(p->name));
   ast_copy_string(p->moh, moh, sizeof(p->moh));
   p->ackcall = ackcall;
   p->autologoff = autologoff;

   /* If someone reduces the wrapuptime and reloads, we want it
    * to change the wrapuptime immediately on all calls */
   if (p->wrapuptime > wrapuptime) {
      struct timeval now = ast_tvnow();
      /* XXX check what is this exactly */

      /* We won't be pedantic and check the tv_usec val */
      if (p->lastdisc.tv_sec > (now.tv_sec + wrapuptime/1000)) {
         p->lastdisc.tv_sec = now.tv_sec + wrapuptime/1000;
         p->lastdisc.tv_usec = now.tv_usec;
      }
   }
   p->wrapuptime = wrapuptime;

   if (pending)
      p->dead = 1;
   else
      p->dead = 0;
   return p;
}

/*!
 * Deletes an agent after doing some clean up.
 * Further documentation: How safe is this function ? What state should the agent be to be cleaned.
 * \param p Agent to be deleted.
 * \returns Always 0.
 */
static int agent_cleanup(struct agent_pvt *p)
{
   struct ast_channel *chan = p->owner;
   p->owner = NULL;
   chan->tech_pvt = NULL;
   p->app_sleep_cond = 1;
   /* Release ownership of the agent to other threads (presumably running the login app). */
   ast_mutex_unlock(&p->app_lock);
   if (chan)
      ast_channel_free(chan);
   if (p->dead) {
      ast_mutex_destroy(&p->lock);
      ast_mutex_destroy(&p->app_lock);
      free(p);
        }
   return 0;
}

static int check_availability(struct agent_pvt *newlyavailable, int needlock);

static int agent_answer(struct ast_channel *ast)
{
   ast_log(LOG_WARNING, "Huh?  Agent is being asked to answer?\n");
   return -1;
}

static int __agent_start_monitoring(struct ast_channel *ast, struct agent_pvt *p, int needlock)
{
   char tmp[AST_MAX_BUF],tmp2[AST_MAX_BUF], *pointer;
   char filename[AST_MAX_BUF];
   int res = -1;
   if (!p)
      return -1;
   if (!ast->monitor) {
      snprintf(filename, sizeof(filename), "agent-%s-%s",p->agent, ast->uniqueid);
      /* substitute . for - */
      if ((pointer = strchr(filename, '.')))
         *pointer = '-';
      snprintf(tmp, sizeof(tmp), "%s%s", savecallsin, filename);
      ast_monitor_start(ast, recordformat, tmp, needlock);
      ast_monitor_setjoinfiles(ast, 1);
      snprintf(tmp2, sizeof(tmp2), "%s%s.%s", urlprefix, filename, recordformatext);
#if 0
      ast_verbose("name is %s, link is %s\n",tmp, tmp2);
#endif
      if (!ast->cdr)
         ast->cdr = ast_cdr_alloc();
      ast_cdr_setuserfield(ast, tmp2);
      res = 0;
   } else
      ast_log(LOG_ERROR, "Recording already started on that call.\n");
   return res;
}

static int agent_start_monitoring(struct ast_channel *ast, int needlock)
{
   return __agent_start_monitoring(ast, ast->tech_pvt, needlock);
}

static struct ast_frame *agent_read(struct ast_channel *ast)
{
   struct agent_pvt *p = ast->tech_pvt;
   struct ast_frame *f = NULL;
   static struct ast_frame answer_frame = { AST_FRAME_CONTROL, AST_CONTROL_ANSWER };
   const char *status;
   ast_mutex_lock(&p->lock); 
   CHECK_FORMATS(ast, p);
   if (p->chan) {
      ast_copy_flags(p->chan, ast, AST_FLAG_EXCEPTION);
      p->chan->fdno = (ast->fdno == AST_AGENT_FD) ? AST_TIMING_FD : ast->fdno;
      f = ast_read(p->chan);
   } else
      f = &ast_null_frame;
   if (!f) {
      /* If there's a channel, hang it up (if it's on a callback) make it NULL */
      if (p->chan) {
         p->chan->_bridge = NULL;
         /* Note that we don't hangup if it's not a callback because Asterisk will do it
            for us when the PBX instance that called login finishes */
         if (!ast_strlen_zero(p->loginchan)) {
            if (p->chan)
               ast_log(LOG_DEBUG, "Bridge on '%s' being cleared (2)\n", p->chan->name);
            if (p->owner->_state != AST_STATE_UP) {
               int howlong = time(NULL) - p->start;
               if (p->autologoff && howlong > p->autologoff) {
                  long logintime = time(NULL) - p->loginstart;
                  p->loginstart = 0;
                     ast_log(LOG_NOTICE, "Agent '%s' didn't answer/confirm within %d seconds (waited %d)\n", p->name, p->autologoff, howlong);
                  agent_logoff_maintenance(p, p->loginchan, logintime, ast->uniqueid, "Autologoff");
                  if (persistent_agents)
                     dump_agents();
               }
            }
            status = pbx_builtin_getvar_helper(p->chan, "CHANLOCALSTATUS");
            if (autologoffunavail && status && !strcasecmp(status, "CHANUNAVAIL")) {
               long logintime = time(NULL) - p->loginstart;
               p->loginstart = 0;
               ast_log(LOG_NOTICE, "Agent read: '%s' is not available now, auto logoff\n", p->name);
               agent_logoff_maintenance(p, p->loginchan, logintime, ast->uniqueid, "Chanunavail");
            }
            ast_hangup(p->chan);
            if (p->wrapuptime && p->acknowledged)
               p->lastdisc = ast_tvadd(ast_tvnow(), ast_samp2tv(p->wrapuptime, 1000));
         }
         p->chan = NULL;
         p->inherited_devicestate = -1;
         ast_device_state_changed("Agent/%s", p->agent);
         p->acknowledged = 0;
      }
   } else {
      /* if acknowledgement is not required, and the channel is up, we may have missed
         an AST_CONTROL_ANSWER (if there was one), so mark the call acknowledged anyway */
      if (!p->ackcall && !p->acknowledged && p->chan && (p->chan->_state == AST_STATE_UP))
         p->acknowledged = 1;
      switch (f->frametype) {
      case AST_FRAME_CONTROL:
         if (f->subclass == AST_CONTROL_ANSWER) {
            if (p->ackcall) {
               if (option_verbose > 2)
                  ast_verbose(VERBOSE_PREFIX_3 "%s answered, waiting for '#' to acknowledge\n", p->chan->name);
               /* Don't pass answer along */
               ast_frfree(f);
               f = &ast_null_frame;
            } else {
               p->acknowledged = 1;
               /* Use the builtin answer frame for the 
                  recording start check below. */
               ast_frfree(f);
               f = &answer_frame;
            }
         }
         break;
      case AST_FRAME_DTMF_BEGIN:
         /*ignore DTMF begin's as it can cause issues with queue announce files*/
         if((!p->acknowledged && f->subclass == '#') || (f->subclass == '*' && endcall)){
            ast_frfree(f);
            f = &ast_null_frame;
         }
         break;
      case AST_FRAME_DTMF_END:
         if (!p->acknowledged && (f->subclass == '#')) {
            if (option_verbose > 2)
               ast_verbose(VERBOSE_PREFIX_3 "%s acknowledged\n", p->chan->name);
            p->acknowledged = 1;
            ast_frfree(f);
            f = &answer_frame;
         } else if (f->subclass == '*' && endcall) {
            /* terminates call */
            ast_frfree(f);
            f = NULL;
         }
         break;
      case AST_FRAME_VOICE:
      case AST_FRAME_VIDEO:
         /* don't pass voice or video until the call is acknowledged */
         if (!p->acknowledged) {
            ast_frfree(f);
            f = &ast_null_frame;
         }
      default:
         /* pass everything else on through */
         break;
      }
   }

   CLEANUP(ast,p);
   if (p->chan && !p->chan->_bridge) {
      if (strcasecmp(p->chan->tech->type, "Local")) {
         p->chan->_bridge = ast;
         if (p->chan)
            ast_log(LOG_DEBUG, "Bridge on '%s' being set to '%s' (3)\n", p->chan->name, p->chan->_bridge->name);
      }
   }
   ast_mutex_unlock(&p->lock);
   if (recordagentcalls && f == &answer_frame)
      agent_start_monitoring(ast,0);
   return f;
}

static int agent_sendhtml(struct ast_channel *ast, int subclass, const char *data, int datalen)
{
   struct agent_pvt *p = ast->tech_pvt;
   int res = -1;
   ast_mutex_lock(&p->lock);
   if (p->chan) 
      res = ast_channel_sendhtml(p->chan, subclass, data, datalen);
   ast_mutex_unlock(&p->lock);
   return res;
}

static int agent_sendtext(struct ast_channel *ast, const char *text)
{
   struct agent_pvt *p = ast->tech_pvt;
   int res = -1;
   ast_mutex_lock(&p->lock);
   if (p->chan) 
      res = ast_sendtext(p->chan, text);
   ast_mutex_unlock(&p->lock);
   return res;
}

static int agent_write(struct ast_channel *ast, struct ast_frame *f)
{
   struct agent_pvt *p = ast->tech_pvt;
   int res = -1;
   CHECK_FORMATS(ast, p);
   ast_mutex_lock(&p->lock);
   if (!p->chan) 
      res = 0;
   else {
      if ((f->frametype != AST_FRAME_VOICE) ||
          (f->frametype != AST_FRAME_VIDEO) ||
          (f->subclass == p->chan->writeformat)) {
         res = ast_write(p->chan, f);
      } else {
         ast_log(LOG_DEBUG, "Dropping one incompatible %s frame on '%s' to '%s'\n", 
            f->frametype == AST_FRAME_VOICE ? "audio" : "video",
            ast->name, p->chan->name);
         res = 0;
      }
   }
   CLEANUP(ast, p);
   ast_mutex_unlock(&p->lock);
   return res;
}

static int agent_fixup(struct ast_channel *oldchan, struct ast_channel *newchan)
{
   struct agent_pvt *p = newchan->tech_pvt;
   ast_mutex_lock(&p->lock);
   if (p->owner != oldchan) {
      ast_log(LOG_WARNING, "old channel wasn't %p but was %p\n", oldchan, p->owner);
      ast_mutex_unlock(&p->lock);
      return -1;
   }
   p->owner = newchan;
   ast_mutex_unlock(&p->lock);
   return 0;
}

static int agent_indicate(struct ast_channel *ast, int condition, const void *data, size_t datalen)
{
   struct agent_pvt *p = ast->tech_pvt;
   int res = -1;
   ast_mutex_lock(&p->lock);
   if (p->chan && !ast_check_hangup(p->chan))
      res = p->chan->tech->indicate ? p->chan->tech->indicate(p->chan, condition, data, datalen) : -1;
   else
      res = 0;
   ast_mutex_unlock(&p->lock);
   return res;
}

static int agent_digit_begin(struct ast_channel *ast, char digit)
{
   struct agent_pvt *p = ast->tech_pvt;
   ast_mutex_lock(&p->lock);
   if (p->chan) {
      ast_senddigit_begin(p->chan, digit);
   }
   ast_mutex_unlock(&p->lock);
   return 0;
}

static int agent_digit_end(struct ast_channel *ast, char digit, unsigned int duration)
{
   struct agent_pvt *p = ast->tech_pvt;
   ast_mutex_lock(&p->lock);
   if (p->chan) {
      ast_senddigit_end(p->chan, digit, duration);
   }
   ast_mutex_unlock(&p->lock);
   return 0;
}

static int agent_call(struct ast_channel *ast, char *dest, int timeout)
{
   struct agent_pvt *p = ast->tech_pvt;
   int res = -1;
   int newstate=0;
   ast_mutex_lock(&p->lock);
   p->acknowledged = 0;
   if (!p->chan) {
      if (p->pending) {
         ast_log(LOG_DEBUG, "Pretending to dial on pending agent\n");
         newstate = AST_STATE_DIALING;
         res = 0;
      } else {
         ast_log(LOG_NOTICE, "Whoa, they hung up between alloc and call...  what are the odds of that?\n");
         res = -1;
      }
      ast_mutex_unlock(&p->lock);
      if (newstate)
         ast_setstate(ast, newstate);
      return res;
   } else if (!ast_strlen_zero(p->loginchan)) {
      time(&p->start);
      /* Call on this agent */
      if (option_verbose > 2)
         ast_verbose(VERBOSE_PREFIX_3 "outgoing agentcall, to agent '%s', on '%s'\n", p->agent, p->chan->name);
      ast_set_callerid(p->chan,
         ast->cid.cid_num, ast->cid.cid_name, NULL);
      ast_channel_inherit_variables(ast, p->chan);
      res = ast_call(p->chan, p->loginchan, 0);
      CLEANUP(ast,p);
      ast_mutex_unlock(&p->lock);
      return res;
   }
   ast_verbose( VERBOSE_PREFIX_3 "agent_call, call to agent '%s' call on '%s'\n", p->agent, p->chan->name);
   if (option_debug > 2)
      ast_log(LOG_DEBUG, "Playing beep, lang '%s'\n", p->chan->language);
   res = ast_streamfile(p->chan, beep, p->chan->language);
   if (option_debug > 2)
      ast_log(LOG_DEBUG, "Played beep, result '%d'\n", res);
   if (!res) {
      res = ast_waitstream(p->chan, "");
      if (option_debug > 2)
         ast_log(LOG_DEBUG, "Waited for stream, result '%d'\n", res);
   }
   if (!res) {
      res = ast_set_read_format(p->chan, ast_best_codec(p->chan->nativeformats));
      if (option_debug > 2)
         ast_log(LOG_DEBUG, "Set read format, result '%d'\n", res);
      if (res)
         ast_log(LOG_WARNING, "Unable to set read format to %s\n", ast_getformatname(ast_best_codec(p->chan->nativeformats)));
   } else {
      /* Agent hung-up */
      p->chan = NULL;
      p->inherited_devicestate = -1;
      ast_device_state_changed("Agent/%s", p->agent);
   }

   if (!res) {
      res = ast_set_write_format(p->chan, ast_best_codec(p->chan->nativeformats));
      if (option_debug > 2)
         ast_log(LOG_DEBUG, "Set write format, result '%d'\n", res);
      if (res)
         ast_log(LOG_WARNING, "Unable to set write format to %s\n", ast_getformatname(ast_best_codec(p->chan->nativeformats)));
   }
   if(!res) {
      /* Call is immediately up, or might need ack */
      if (p->ackcall > 1)
         newstate = AST_STATE_RINGING;
      else {
         newstate = AST_STATE_UP;
         if (recordagentcalls)
            agent_start_monitoring(ast, 0);
         p->acknowledged = 1;
      }
      res = 0;
   }
   CLEANUP(ast, p);
   ast_mutex_unlock(&p->lock);
   if (newstate)
      ast_setstate(ast, newstate);
   return res;
}

/*! \brief store/clear the global variable that stores agentid based on the callerid */
static void set_agentbycallerid(const char *callerid, const char *agent)
{
   char buf[AST_MAX_BUF];

   /* if there is no Caller ID, nothing to do */
   if (ast_strlen_zero(callerid))
      return;

   snprintf(buf, sizeof(buf), "%s_%s", GETAGENTBYCALLERID, callerid);
   pbx_builtin_setvar_helper(NULL, buf, agent);