chan_phone.c

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/*
 * Asterisk -- An open source telephony toolkit.
 *
 * Copyright (C) 1999 - 2005, Digium, Inc.
 *
 * Mark Spencer <[email protected]>
 *
 * 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 Generic Linux Telephony Interface driver
 *
 * \author Mark Spencer <[email protected]>
 *
 * \ingroup channel_drivers
 */

/*! \li \ref chan_phone.c uses the configuration file \ref phone.conf
 * \addtogroup configuration_file
 */

/*! \page phone.conf phone.conf
 * \verbinclude phone.conf.sample
 */

/*** MODULEINFO
   <depend>ixjuser</depend>
   <support_level>deprecated</support_level>
 ***/

#include "asterisk.h"

#include <ctype.h>
#include <sys/socket.h>
#include <sys/time.h>
#include <arpa/inet.h>
#include <fcntl.h>
#include <sys/ioctl.h>
#include <signal.h>
#ifdef HAVE_LINUX_COMPILER_H
#include <linux/compiler.h>
#endif
#include <linux/telephony.h>
/* Still use some IXJ specific stuff */
#include <linux/version.h>
#include <linux/ixjuser.h>

#include "asterisk/lock.h"
#include "asterisk/channel.h"
#include "asterisk/config.h"
#include "asterisk/module.h"
#include "asterisk/pbx.h"
#include "asterisk/utils.h"
#include "asterisk/callerid.h"
#include "asterisk/causes.h"
#include "asterisk/stringfields.h"
#include "asterisk/musiconhold.h"
#include "asterisk/format_cache.h"
#include "asterisk/format_compatibility.h"

#include "chan_phone.h"

#ifdef QTI_PHONEJACK_TJ_PCI   /* check for the newer quicknet driver v.3.1.0 which has this symbol */
#define QNDRV_VER 310
#else
#define QNDRV_VER 100
#endif

#if QNDRV_VER > 100
#ifdef __linux__
#define IXJ_PHONE_RING_START(x)  ioctl(p->fd, PHONE_RING_START, &x);
#else /* FreeBSD and others */
#define IXJ_PHONE_RING_START(x)  ioctl(p->fd, PHONE_RING_START, x);
#endif /* __linux__ */
#else /* older driver */
#define IXJ_PHONE_RING_START(x)  ioctl(p->fd, PHONE_RING_START, &x);
#endif

#define DEFAULT_CALLER_ID "Unknown"
#define PHONE_MAX_BUF 480
#define DEFAULT_GAIN 0x100

static const char tdesc[] = "Standard Linux Telephony API Driver";
static const char config[] = "phone.conf";

/* Default context for dialtone mode */
static char context[AST_MAX_EXTENSION] = "default";

/* Default language */
static char language[MAX_LANGUAGE] = "";

static int echocancel = AEC_OFF;

static int silencesupression = 0;

static struct ast_format_cap *prefcap;

/* Protect the interface list (of phone_pvt's) */
AST_MUTEX_DEFINE_STATIC(iflock);

/* Protect the monitoring thread, so only one process can kill or start it, and not
   when it's doing something critical. */
AST_MUTEX_DEFINE_STATIC(monlock);

/* Boolean value whether the monitoring thread shall continue. */
static unsigned int monitor;

/* This is the thread for the monitor which checks for input on the channels
   which are not currently in use.  */
static pthread_t monitor_thread = AST_PTHREADT_NULL;

static int restart_monitor(void);

/* The private structures of the Phone Jack channels are linked for
   selecting outgoing channels */

#define MODE_DIALTONE   1
#define MODE_IMMEDIATE  2
#define MODE_FXO  3
#define MODE_FXS        4
#define MODE_SIGMA      5

static struct phone_pvt {
   int fd;                    /* Raw file descriptor for this device */
   struct ast_channel *owner;    /* Channel we belong to, possibly NULL */
   int mode;                  /* Is this in the  */
   struct ast_format *lastformat;            /* Last output format */
   struct ast_format *lastinput;             /* Last input format */
   int ministate;             /* Miniature state, for dialtone mode */
   char dev[256];             /* Device name */
   struct phone_pvt *next;       /* Next channel in list */
   struct ast_frame fr;       /* Frame */
   char offset[AST_FRIENDLY_OFFSET];
   char buf[PHONE_MAX_BUF];               /* Static buffer for reading frames */
   int obuflen;
   int dialtone;
   int txgain, rxgain;             /* gain control for playing, recording  */
                           /* 0x100 - 1.0, 0x200 - 2.0, 0x80 - 0.5 */
   int cpt;                /* Call Progress Tone playing? */
   int silencesupression;
   char context[AST_MAX_EXTENSION];
   char obuf[PHONE_MAX_BUF * 2];
   char ext[AST_MAX_EXTENSION];
   char language[MAX_LANGUAGE];
   char cid_num[AST_MAX_EXTENSION];
   char cid_name[AST_MAX_EXTENSION];
} *iflist = NULL;

static char cid_num[AST_MAX_EXTENSION];
static char cid_name[AST_MAX_EXTENSION];

static struct ast_channel *phone_request(const char *type, struct ast_format_cap *cap, const struct ast_assigned_ids *assignedids, const struct ast_channel *requestor, const char *data, int *cause);
static int phone_digit_begin(struct ast_channel *ast, char digit);
static int phone_digit_end(struct ast_channel *ast, char digit, unsigned int duration);
static int phone_call(struct ast_channel *ast, const char *dest, int timeout);
static int phone_hangup(struct ast_channel *ast);
static int phone_answer(struct ast_channel *ast);
static struct ast_frame *phone_read(struct ast_channel *ast);
static int phone_write(struct ast_channel *ast, struct ast_frame *frame);
static struct ast_frame *phone_exception(struct ast_channel *ast);
static int phone_send_text(struct ast_channel *ast, const char *text);
static int phone_fixup(struct ast_channel *old, struct ast_channel *new);
static int phone_indicate(struct ast_channel *chan, int condition, const void *data, size_t datalen);

static struct ast_channel_tech phone_tech = {
   .type = "Phone",
   .description = tdesc,
   .requester = phone_request,
   .send_digit_begin = phone_digit_begin,
   .send_digit_end = phone_digit_end,
   .call = phone_call,
   .hangup = phone_hangup,
   .answer = phone_answer,
   .read = phone_read,
   .write = phone_write,
   .exception = phone_exception,
   .indicate = phone_indicate,
   .fixup = phone_fixup
};

static struct ast_channel_tech phone_tech_fxs = {
   .type = "Phone",
   .description = tdesc,
   .requester = phone_request,
   .send_digit_begin = phone_digit_begin,
   .send_digit_end = phone_digit_end,
   .call = phone_call,
   .hangup = phone_hangup,
   .answer = phone_answer,
   .read = phone_read,
   .write = phone_write,
   .exception = phone_exception,
   .write_video = phone_write,
   .send_text = phone_send_text,
   .indicate = phone_indicate,
   .fixup = phone_fixup
};

static struct ast_channel_tech *cur_tech;

static int phone_indicate(struct ast_channel *chan, int condition, const void *data, size_t datalen)
{
   struct phone_pvt *p = ast_channel_tech_pvt(chan);
   int res=-1;
   ast_debug(1, "Requested indication %d on channel %s\n", condition, ast_channel_name(chan));
   switch(condition) {
   case AST_CONTROL_FLASH:
      ioctl(p->fd, IXJCTL_PSTN_SET_STATE, PSTN_ON_HOOK);
      usleep(320000);
      ioctl(p->fd, IXJCTL_PSTN_SET_STATE, PSTN_OFF_HOOK);
      ao2_cleanup(p->lastformat);
      p->lastformat = NULL;
      res = 0;
      break;
   case AST_CONTROL_HOLD:
      ast_moh_start(chan, data, NULL);
      break;
   case AST_CONTROL_UNHOLD:
      ast_moh_stop(chan);
      break;
   case AST_CONTROL_SRCUPDATE:
      res = 0;
      break;
   case AST_CONTROL_PVT_CAUSE_CODE:
      break;
   default:
      ast_log(LOG_WARNING, "Condition %d is not supported on channel %s\n", condition, ast_channel_name(chan));
   }
   return res;
}

static int phone_fixup(struct ast_channel *old, struct ast_channel *new)
{
   struct phone_pvt *pvt = ast_channel_tech_pvt(old);
   if (pvt && pvt->owner == old)
      pvt->owner = new;
   return 0;
}

static int phone_digit_begin(struct ast_channel *chan, char digit)
{
   /* XXX Modify this callback to let Asterisk support controlling the length of DTMF */
   return 0;
}

static int phone_digit_end(struct ast_channel *ast, char digit, unsigned int duration)
{
   struct phone_pvt *p;
   int outdigit;
   p = ast_channel_tech_pvt(ast);
   ast_debug(1, "Dialed %c\n", digit);
   switch(digit) {
   case '0':
   case '1':
   case '2':
   case '3':
   case '4':
   case '5':
   case '6':
   case '7':
   case '8':
   case '9':
      outdigit = digit - '0';
      break;
   case '*':
      outdigit = 11;
      break;
   case '#':
      outdigit = 12;
      break;
   case 'f':   /*flash*/
   case 'F':
      ioctl(p->fd, IXJCTL_PSTN_SET_STATE, PSTN_ON_HOOK);
      usleep(320000);
      ioctl(p->fd, IXJCTL_PSTN_SET_STATE, PSTN_OFF_HOOK);
      ao2_cleanup(p->lastformat);
      p->lastformat = NULL;
      return 0;
   default:
      ast_log(LOG_WARNING, "Unknown digit '%c'\n", digit);
      return -1;
   }
   ast_debug(1, "Dialed %d\n", outdigit);
   ioctl(p->fd, PHONE_PLAY_TONE, outdigit);
   ao2_cleanup(p->lastformat);
   p->lastformat = NULL;
   return 0;
}

static int phone_call(struct ast_channel *ast, const char *dest, int timeout)
{
   struct phone_pvt *p;

   PHONE_CID cid;
   struct timeval UtcTime = ast_tvnow();
   struct ast_tm tm;
   int start;

   ast_localtime(&UtcTime, &tm, NULL);

   memset(&cid, 0, sizeof(PHONE_CID));
    snprintf(cid.month, sizeof(cid.month), "%02d",(tm.tm_mon + 1));
    snprintf(cid.day, sizeof(cid.day),     "%02d", tm.tm_mday);
    snprintf(cid.hour, sizeof(cid.hour),   "%02d", tm.tm_hour);
    snprintf(cid.min, sizeof(cid.min),     "%02d", tm.tm_min);
   /* the standard format of ast->callerid is:  "name" <number>, but not always complete */
   if (!ast_channel_connected(ast)->id.name.valid
      || ast_strlen_zero(ast_channel_connected(ast)->id.name.str)) {
      strcpy(cid.name, DEFAULT_CALLER_ID);
   } else {
      ast_copy_string(cid.name, ast_channel_connected(ast)->id.name.str, sizeof(cid.name));
   }

   if (ast_channel_connected(ast)->id.number.valid && ast_channel_connected(ast)->id.number.str) {
      ast_copy_string(cid.number, ast_channel_connected(ast)->id.number.str, sizeof(cid.number));
   }

   p = ast_channel_tech_pvt(ast);

   if ((ast_channel_state(ast) != AST_STATE_DOWN) && (ast_channel_state(ast) != AST_STATE_RESERVED)) {
      ast_log(LOG_WARNING, "phone_call called on %s, neither down nor reserved\n", ast_channel_name(ast));
      return -1;
   }
   ast_debug(1, "Ringing %s on %s (%d)\n", dest, ast_channel_name(ast), ast_channel_fd(ast, 0));

   start = IXJ_PHONE_RING_START(cid);
   if (start == -1)
      return -1;

   if (p->mode == MODE_FXS) {
      const char *digit = strchr(dest, '/');
      if (digit)
      {
        digit++;
        while (*digit)
          phone_digit_end(ast, *digit++, 0);
      }
   }

   ast_setstate(ast, AST_STATE_RINGING);
   ast_queue_control(ast, AST_CONTROL_RINGING);
   return 0;
}

static int phone_hangup(struct ast_channel *ast)
{
   struct phone_pvt *p;
   p = ast_channel_tech_pvt(ast);
   ast_debug(1, "phone_hangup(%s)\n", ast_channel_name(ast));
   if (!ast_channel_tech_pvt(ast)) {
      ast_log(LOG_WARNING, "Asked to hangup channel not connected\n");
      return 0;
   }
   /* XXX Is there anything we can do to really hang up except stop recording? */
   ast_setstate(ast, AST_STATE_DOWN);
   if (ioctl(p->fd, PHONE_REC_STOP))
      ast_log(LOG_WARNING, "Failed to stop recording\n");
   if (ioctl(p->fd, PHONE_PLAY_STOP))
      ast_log(LOG_WARNING, "Failed to stop playing\n");
   if (ioctl(p->fd, PHONE_RING_STOP))
      ast_log(LOG_WARNING, "Failed to stop ringing\n");
   if (ioctl(p->fd, PHONE_CPT_STOP))
      ast_log(LOG_WARNING, "Failed to stop sounds\n");

   /* If it's an FXO, hang them up */
   if (p->mode == MODE_FXO) {
      if (ioctl(p->fd, PHONE_PSTN_SET_STATE, PSTN_ON_HOOK))
         ast_debug(1, "ioctl(PHONE_PSTN_SET_STATE) failed on %s (%s)\n",ast_channel_name(ast), strerror(errno));
   }

   /* If they're off hook, give a busy signal */
   if (ioctl(p->fd, PHONE_HOOKSTATE)) {
      ast_debug(1, "Got hunghup, giving busy signal\n");
      ioctl(p->fd, PHONE_BUSY);
      p->cpt = 1;
   }
   ao2_cleanup(p->lastformat);
   p->lastformat = NULL;
   ao2_cleanup(p->lastinput);
   p->lastinput = NULL;
   p->ministate = 0;
   p->obuflen = 0;
   p->dialtone = 0;
   memset(p->ext, 0, sizeof(p->ext));
   ((struct phone_pvt *)(ast_channel_tech_pvt(ast)))->owner = NULL;
   ast_module_unref(ast_module_info->self);
   ast_verb(3, "Hungup '%s'\n", ast_channel_name(ast));
   ast_channel_tech_pvt_set(ast, NULL);
   ast_setstate(ast, AST_STATE_DOWN);
   restart_monitor();
   return 0;
}

static int phone_setup(struct ast_channel *ast)
{
   struct phone_pvt *p;
   p = ast_channel_tech_pvt(ast);
   ioctl(p->fd, PHONE_CPT_STOP);
   /* Nothing to answering really, just start recording */
   if (ast_format_cmp(ast_channel_rawreadformat(ast), ast_format_g729) == AST_FORMAT_CMP_EQUAL) {
      /* Prefer g729 */
      ioctl(p->fd, PHONE_REC_STOP);
      if (!p->lastinput || (ast_format_cmp(p->lastinput, ast_format_g729) != AST_FORMAT_CMP_EQUAL)) {
         ao2_replace(p->lastinput, ast_format_g729);
         if (ioctl(p->fd, PHONE_REC_CODEC, G729)) {
            ast_log(LOG_WARNING, "Failed to set codec to g729\n");
            return -1;
         }
      }
   } else if (ast_format_cmp(ast_channel_rawreadformat(ast), ast_format_g723) == AST_FORMAT_CMP_EQUAL) {
      ioctl(p->fd, PHONE_REC_STOP);
      if (!p->lastinput || (ast_format_cmp(p->lastinput, ast_format_g723) != AST_FORMAT_CMP_EQUAL)) {
         ao2_replace(p->lastinput, ast_format_g723);
         if (ioctl(p->fd, PHONE_REC_CODEC, G723_63)) {
            ast_log(LOG_WARNING, "Failed to set codec to g723.1\n");
            return -1;
         }
      }
   } else if (ast_format_cmp(ast_channel_rawreadformat(ast), ast_format_slin) == AST_FORMAT_CMP_EQUAL) {
      ioctl(p->fd, PHONE_REC_STOP);
      if (!p->lastinput || (ast_format_cmp(p->lastinput, ast_format_slin) != AST_FORMAT_CMP_EQUAL)) {
         ao2_replace(p->lastinput, ast_format_slin);
         if (ioctl(p->fd, PHONE_REC_CODEC, LINEAR16)) {
            ast_log(LOG_WARNING, "Failed to set codec to signed linear 16\n");
            return -1;
         }
      }
   } else if (ast_format_cmp(ast_channel_rawreadformat(ast), ast_format_ulaw) == AST_FORMAT_CMP_EQUAL) {
      ioctl(p->fd, PHONE_REC_STOP);
      if (!p->lastinput || (ast_format_cmp(p->lastinput, ast_format_ulaw) != AST_FORMAT_CMP_EQUAL)) {
         ao2_replace(p->lastinput, ast_format_ulaw);
         if (ioctl(p->fd, PHONE_REC_CODEC, ULAW)) {
            ast_log(LOG_WARNING, "Failed to set codec to uLaw\n");
            return -1;
         }
      }
   } else if (p->mode == MODE_FXS) {
      ioctl(p->fd, PHONE_REC_STOP);
      if (!p->lastinput || (ast_format_cmp(p->lastinput, ast_channel_rawreadformat(ast)) == AST_FORMAT_CMP_NOT_EQUAL)) {
         ao2_replace(p->lastinput, ast_channel_rawreadformat(ast));
         if (ioctl(p->fd, PHONE_REC_CODEC, ast_channel_rawreadformat(ast))) {
            ast_log(LOG_WARNING, "Failed to set codec to %s\n",
               ast_format_get_name(ast_channel_rawreadformat(ast)));
            return -1;
         }
      }
   } else {
      ast_log(LOG_WARNING, "Can't do format %s\n", ast_format_get_name(ast_channel_rawreadformat(ast)));
      return -1;
   }
   if (ioctl(p->fd, PHONE_REC_START)) {
      ast_log(LOG_WARNING, "Failed to start recording\n");
      return -1;
   }
   /* set the DTMF times (the default is too short) */
   ioctl(p->fd, PHONE_SET_TONE_ON_TIME, 300);
   ioctl(p->fd, PHONE_SET_TONE_OFF_TIME, 200);
   return 0;
}

static int phone_answer(struct ast_channel *ast)
{
   struct phone_pvt *p;
   p = ast_channel_tech_pvt(ast);
   /* In case it's a LineJack, take it off hook */
   if (p->mode == MODE_FXO) {
      if (ioctl(p->fd, PHONE_PSTN_SET_STATE, PSTN_OFF_HOOK))
         ast_debug(1, "ioctl(PHONE_PSTN_SET_STATE) failed on %s (%s)\n", ast_channel_name(ast), strerror(errno));
      else
         ast_debug(1, "Took linejack off hook\n");
   }
   phone_setup(ast);
   ast_debug(1, "phone_answer(%s)\n", ast_channel_name(ast));
   ast_channel_rings_set(ast, 0);
   ast_setstate(ast, AST_STATE_UP);
   return 0;
}

#if 0
static char phone_2digit(char c)
{
   if (c == 12)
      return '#';
   else if (c == 11)
      return '*';
   else if ((c < 10) && (c >= 0))
      return '0' + c - 1;
   else
      return '?';
}
#endif

static struct ast_frame  *phone_exception(struct ast_channel *ast)
{
   int res;
   union telephony_exception phonee;
   struct phone_pvt *p = ast_channel_tech_pvt(ast);
   char digit;

   /* Some nice norms */
   p->fr.datalen = 0;
   p->fr.samples = 0;
   p->fr.data.ptr =  NULL;
   p->fr.src = "Phone";
   p->fr.offset = 0;
   p->fr.mallocd=0;
   p->fr.delivery = ast_tv(0,0);

   phonee.bytes = ioctl(p->fd, PHONE_EXCEPTION);
   if (phonee.bits.dtmf_ready)  {
      ast_debug(1, "phone_exception(): DTMF\n");

      /* We've got a digit -- Just handle this nicely and easily */
      digit =  ioctl(p->fd, PHONE_GET_DTMF_ASCII);
      p->fr.subclass.integer = digit;
      p->fr.frametype = AST_FRAME_DTMF;
      return &p->fr;
   }
   if (phonee.bits.hookstate) {
      ast_debug(1, "Hookstate changed\n");
      res = ioctl(p->fd, PHONE_HOOKSTATE);
      /* See if we've gone on hook, if so, notify by returning NULL */
      ast_debug(1, "New hookstate: %d\n", res);
      if (!res && (p->mode != MODE_FXO))
         return NULL;
      else {
         if (ast_channel_state(ast) == AST_STATE_RINGING) {
            /* They've picked up the phone */
            p->fr.frametype = AST_FRAME_CONTROL;
            p->fr.subclass.integer = AST_CONTROL_ANSWER;
            phone_setup(ast);
            ast_setstate(ast, AST_STATE_UP);
            return &p->fr;
         }  else
            ast_log(LOG_WARNING, "Got off hook in weird state %u\n", ast_channel_state(ast));
      }
   }
#if 1
   if (phonee.bits.pstn_ring)
      ast_verbose("Unit is ringing\n");
   if (phonee.bits.caller_id) {
      ast_verbose("We have caller ID\n");
   }
   if (phonee.bits.pstn_wink)
      ast_verbose("Detected Wink\n");
#endif
   /* Strange -- nothing there.. */
   p->fr.frametype = AST_FRAME_NULL;
   p->fr.subclass.integer = 0;
   return &p->fr;
}

static struct ast_frame  *phone_read(struct ast_channel *ast)
{
   int res;
   struct phone_pvt *p = ast_channel_tech_pvt(ast);


   /* Some nice norms */
   p->fr.datalen = 0;
   p->fr.samples = 0;
   p->fr.data.ptr =  NULL;
   p->fr.src = "Phone";
   p->fr.offset = 0;
   p->fr.mallocd=0;
   p->fr.delivery = ast_tv(0,0);

   /* Try to read some data... */
   CHECK_BLOCKING(ast);
   res = read(p->fd, p->buf, PHONE_MAX_BUF);
   ast_clear_flag(ast_channel_flags(ast), AST_FLAG_BLOCKING);
   if (res < 0) {
#if 0
      if (errno == EAGAIN) {
         ast_log(LOG_WARNING, "Null frame received\n");
         p->fr.frametype = AST_FRAME_NULL;
         p->fr.subclass = 0;
         return &p->fr;
      }
#endif
      ast_log(LOG_WARNING, "Error reading: %s\n", strerror(errno));
      return NULL;
   }
   p->fr.data.ptr = p->buf;
   if (p->mode != MODE_FXS)
   switch(p->buf[0] & 0x3) {
   case '0':
   case '1':
      /* Normal */
      break;
   case '2':
   case '3':
      /* VAD/CNG, only send two words */
      res = 4;
      break;
   }
   p->fr.samples = 240;
   p->fr.datalen = res;
   p->fr.frametype = ast_format_get_type(p->lastinput) == AST_MEDIA_TYPE_AUDIO ?
      AST_FRAME_VOICE : ast_format_get_type(p->lastinput) == AST_MEDIA_TYPE_IMAGE ?
      AST_FRAME_IMAGE : AST_FRAME_VIDEO;
   p->fr.subclass.format = p->lastinput;
   p->fr.offset = AST_FRIENDLY_OFFSET;
   /* Byteswap from little-endian to native-endian */
   if (ast_format_cmp(p->fr.subclass.format, ast_format_slin) == AST_FORMAT_CMP_EQUAL)
      ast_frame_byteswap_le(&p->fr);
   return &p->fr;
}

static int phone_write_buf(struct phone_pvt *p, const char *buf, int len, int frlen, int swap)
{
   int res;
   /* Store as much of the buffer as we can, then write fixed frames */
   int space = sizeof(p->obuf) - p->obuflen;
   /* Make sure we have enough buffer space to store the frame */
   if (space < len)
      len = space;
   if (swap)
      ast_swapcopy_samples(p->obuf+p->obuflen, buf, len/2);
   else
      memcpy(p->obuf + p->obuflen, buf, len);
   p->obuflen += len;
   while(p->obuflen > frlen) {
      res = write(p->fd, p->obuf, frlen);
      if (res != frlen) {
         if (res < 1) {
/*
 * Card is in non-blocking mode now and it works well now, but there are
 * lot of messages like this. So, this message is temporarily disabled.
 */
            return 0;
         } else {
            ast_log(LOG_WARNING, "Only wrote %d of %d bytes\n", res, frlen);
         }
      }
      p->obuflen -= frlen;
      /* Move memory if necessary */
      if (p->obuflen)
         memmove(p->obuf, p->obuf + frlen, p->obuflen);
   }
   return len;
}

static int phone_send_text(struct ast_channel *ast, const char *text)
{
    int length = strlen(text);
    return phone_write_buf(ast_channel_tech_pvt(ast), text, length, length, 0) ==
           length ? 0 : -1;
}

static int phone_write(struct ast_channel *ast, struct ast_frame *frame)
{
   struct phone_pvt *p = ast_channel_tech_pvt(ast);
   int res;
   int maxfr=0;
   char *pos;
   int sofar;
   int expected;
   int codecset = 0;
   char tmpbuf[4];
   /* Write a frame of (presumably voice) data */
   if (frame->frametype != AST_FRAME_VOICE && p->mode != MODE_FXS) {
      if (frame->frametype != AST_FRAME_IMAGE)
         ast_log(LOG_WARNING, "Don't know what to do with  frame type '%u'\n", frame->frametype);
      return 0;
   }
#if 0
   /* If we're not in up mode, go into up mode now */
   if (ast->_state != AST_STATE_UP) {
      ast_setstate(ast, AST_STATE_UP);
      phone_setup(ast);
   }
#else
   if (ast_channel_state(ast) != AST_STATE_UP) {
      /* Don't try tos end audio on-hook */
      return 0;
   }
#endif
   if (ast_format_cmp(frame->subclass.format, ast_format_g729) == AST_FORMAT_CMP_EQUAL) {
      if (!p->lastformat || (ast_format_cmp(p->lastformat, ast_format_g729) != AST_FORMAT_CMP_EQUAL)) {
         ioctl(p->fd, PHONE_PLAY_STOP);
         ioctl(p->fd, PHONE_REC_STOP);
         if (ioctl(p->fd, PHONE_PLAY_CODEC, G729)) {
            ast_log(LOG_WARNING, "Unable to set G729 mode\n");
            return -1;
         }
         if (ioctl(p->fd, PHONE_REC_CODEC, G729)) {
            ast_log(LOG_WARNING, "Unable to set G729 mode\n");
            return -1;
         }
         ao2_replace(p->lastformat, ast_format_g729);
         ao2_replace(p->lastinput, ast_format_g729);
         /* Reset output buffer */
         p->obuflen = 0;
         codecset = 1;
      }
      if (frame->datalen > 80) {
         ast_log(LOG_WARNING, "Frame size too large for G.729 (%d bytes)\n", frame->datalen);
         return -1;
      }
      maxfr = 80;
    } else if (ast_format_cmp(frame->subclass.format, ast_format_g723) == AST_FORMAT_CMP_EQUAL) {
      if (!p->lastformat || (ast_format_cmp(p->lastformat, ast_format_g723) != AST_FORMAT_CMP_EQUAL)) {
         ioctl(p->fd, PHONE_PLAY_STOP);
         ioctl(p->fd, PHONE_REC_STOP);
         if (ioctl(p->fd, PHONE_PLAY_CODEC, G723_63)) {
            ast_log(LOG_WARNING, "Unable to set G723.1 mode\n");
            return -1;
         }
         if (ioctl(p->fd, PHONE_REC_CODEC, G723_63)) {
            ast_log(LOG_WARNING, "Unable to set G723.1 mode\n");
            return -1;
         }
         ao2_replace(p->lastformat, ast_format_g723);
         ao2_replace(p->lastinput, ast_format_g723);
         /* Reset output buffer */
         p->obuflen = 0;
         codecset = 1;
      }
      if (frame->datalen > 24) {
         ast_log(LOG_WARNING, "Frame size too large for G.723.1 (%d bytes)\n", frame->datalen);
         return -1;
      }
      maxfr = 24;
   } else if (ast_format_cmp(frame->subclass.format, ast_format_slin) == AST_FORMAT_CMP_EQUAL) {
      if (!p->lastformat || (ast_format_cmp(p->lastformat, ast_format_slin) != AST_FORMAT_CMP_EQUAL)) {
         ioctl(p->fd, PHONE_PLAY_STOP);
         ioctl(p->fd, PHONE_REC_STOP);
         if (ioctl(p->fd, PHONE_PLAY_CODEC, LINEAR16)) {
            ast_log(LOG_WARNING, "Unable to set 16-bit linear mode\n");
            return -1;
         }
         if (ioctl(p->fd, PHONE_REC_CODEC, LINEAR16)) {
            ast_log(LOG_WARNING, "Unable to set 16-bit linear mode\n");
            return -1;
         }
         ao2_replace(p->lastformat, ast_format_slin);
         ao2_replace(p->lastinput, ast_format_slin);
         codecset = 1;
         /* Reset output buffer */
         p->obuflen = 0;
      }
      maxfr = 480;
   } else if (ast_format_cmp(frame->subclass.format, ast_format_ulaw) == AST_FORMAT_CMP_EQUAL) {
      if (!p->lastformat || (ast_format_cmp(p->lastformat, ast_format_ulaw) != AST_FORMAT_CMP_EQUAL)) {
         ioctl(p->fd, PHONE_PLAY_STOP);
         ioctl(p->fd, PHONE_REC_STOP);
         if (ioctl(p->fd, PHONE_PLAY_CODEC, ULAW)) {
            ast_log(LOG_WARNING, "Unable to set uLaw mode\n");
            return -1;
         }
         if (ioctl(p->fd, PHONE_REC_CODEC, ULAW)) {
            ast_log(LOG_WARNING, "Unable to set uLaw mode\n");
            return -1;
         }
         ao2_replace(p->lastformat, ast_format_ulaw);
         ao2_replace(p->lastinput, ast_format_ulaw);
         codecset = 1;
         /* Reset output buffer */
         p->obuflen = 0;
      }
      maxfr = 240;
   } else {
      if (!p->lastformat || (ast_format_cmp(p->lastformat, frame->subclass.format) != AST_FORMAT_CMP_EQUAL)) {
         ioctl(p->fd, PHONE_PLAY_STOP);
         ioctl(p->fd, PHONE_REC_STOP);
         if (ioctl(p->fd, PHONE_PLAY_CODEC, ast_format_compatibility_format2bitfield(frame->subclass.format))) {
            ast_log(LOG_WARNING, "Unable to set %s mode\n",
               ast_format_get_name(frame->subclass.format));
            return -1;
         }
         if (ioctl(p->fd, PHONE_REC_CODEC, ast_format_compatibility_format2bitfield(frame->subclass.format))) {
            ast_log(LOG_WARNING, "Unable to set %s mode\n",
               ast_format_get_name(frame->subclass.format));
            return -1;
         }
         ao2_replace(p->lastformat, frame->subclass.format);
         ao2_replace(p->lastinput, frame->subclass.format);
         codecset = 1;
         /* Reset output buffer */
         p->obuflen = 0;
      }
      maxfr = 480;
   }
   if (codecset) {
      ioctl(p->fd, PHONE_REC_DEPTH, 3);
      ioctl(p->fd, PHONE_PLAY_DEPTH, 3);
      if (ioctl(p->fd, PHONE_PLAY_START)) {
         ast_log(LOG_WARNING, "Failed to start playback\n");
         return -1;
      }
      if (ioctl(p->fd, PHONE_REC_START)) {
         ast_log(LOG_WARNING, "Failed to start recording\n");
         return -1;
      }
   }
   /* If we get here, we have a frame of Appropriate data */
   sofar = 0;
   pos = frame->data.ptr;
   while(sofar < frame->datalen) {
      /* Write in no more than maxfr sized frames */
      expected = frame->datalen - sofar;
      if (maxfr < expected)
         expected = maxfr;
      /* XXX Internet Phone Jack does not handle the 4-byte VAD frame properly! XXX
         we have to pad it to 24 bytes still.  */
      if (frame->datalen == 4) {
         if (p->silencesupression) {
            memcpy(tmpbuf, frame->data.ptr, 4);
            expected = 24;
            res = phone_write_buf(p, tmpbuf, expected, maxfr, 0);
         }
         res = 4;
         expected=4;
      } else {
         int swap = 0;
#if __BYTE_ORDER == __BIG_ENDIAN
         if (ast_format_cmp(frame->subclass.format, ast_format_slin) == AST_FORMAT_CMP_EQUAL)
            swap = 1; /* Swap big-endian samples to little-endian as we copy */
#endif
         res = phone_write_buf(p, pos, expected, maxfr, swap);
      }
      if (res != expected) {
         if ((errno != EAGAIN) && (errno != EINTR)) {
            if (res < 0)
               ast_log(LOG_WARNING, "Write returned error (%s)\n", strerror(errno));
   /*
    * Card is in non-blocking mode now and it works well now, but there are
    * lot of messages like this. So, this message is temporarily disabled.
    */
#if 0
            else
               ast_log(LOG_WARNING, "Only wrote %d of %d bytes\n", res, frame->datalen);
#endif
            return -1;
         } else /* Pretend it worked */
            res = expected;
      }
      sofar += res;
      pos += res;
   }
   return 0;
}

static struct ast_channel *phone_new(struct phone_pvt *i, int state, char *cntx, const struct ast_assigned_ids *assignedids, const struct ast_channel *requestor)
{
   struct ast_format_cap *caps = NULL;
   struct ast_channel *tmp;
   struct phone_codec_data queried_codec;
   struct ast_format *tmpfmt;
   caps = ast_format_cap_alloc(AST_FORMAT_CAP_FLAG_DEFAULT);
   tmp = ast_channel_alloc(1, state, i->cid_num, i->cid_name, "", i->ext, i->context, assignedids, requestor, 0, "Phone/%s", i->dev + 5);
   if (tmp && caps) {
      ast_channel_lock(tmp);
      ast_channel_tech_set(tmp, cur_tech);
      ast_channel_set_fd(tmp, 0, i->fd);
      /* XXX Switching formats silently causes kernel panics XXX */
      if (i->mode == MODE_FXS &&
          ioctl(i->fd, PHONE_QUERY_CODEC, &queried_codec) == 0) {
         if (queried_codec.type == LINEAR16) {
            ast_format_cap_append(caps, ast_format_slin, 0);
         } else {
            ast_format_cap_remove(prefcap, ast_format_slin);
            ast_format_cap_append_from_cap(caps, prefcap, AST_MEDIA_TYPE_UNKNOWN);
         }
      } else {
         ast_format_cap_append_from_cap(caps, prefcap, AST_MEDIA_TYPE_UNKNOWN);
      }
      tmpfmt = ast_format_cap_get_format(caps, 0);
      ast_channel_nativeformats_set(tmp, caps);
      ao2_ref(caps, -1);
      ast_channel_set_rawreadformat(tmp, tmpfmt);
      ast_channel_set_rawwriteformat(tmp, tmpfmt);
      ao2_ref(tmpfmt, -1);
      /* no need to call ast_setstate: the channel_alloc already did its job */
      if (state == AST_STATE_RING)
         ast_channel_rings_set(tmp, 1);
      ast_channel_tech_pvt_set(tmp, i);
      ast_channel_context_set(tmp, cntx);
      if (!ast_strlen_zero(i->ext))
         ast_channel_exten_set(tmp, i->ext);
      else
         ast_channel_exten_set(tmp, "s");
      if (!ast_strlen_zero(i->language))
         ast_channel_language_set(tmp, i->language);

      /* Don't use ast_set_callerid() here because it will
       * generate a NewCallerID event before the NewChannel event */
      if (!ast_strlen_zero(i->cid_num)) {
         ast_channel_caller(tmp)->ani.number.valid = 1;
         ast_channel_caller(tmp)->ani.number.str = ast_strdup(i->cid_num);
      }

      i->owner = tmp;
      ast_module_ref(ast_module_info->self);
      ast_channel_unlock(tmp);
      if (state != AST_STATE_DOWN) {
         if (state == AST_STATE_RING) {
            ioctl(ast_channel_fd(tmp, 0), PHONE_RINGBACK);
            i->cpt = 1;
         }
         if (ast_pbx_start(tmp)) {
            ast_log(LOG_WARNING, "Unable to start PBX on %s\n", ast_channel_name(tmp));
            ast_hangup(tmp);
         }
      }
   } else {
      ao2_cleanup(caps);
      ast_log(LOG_WARNING, "Unable to allocate channel structure\n");
   }
   return tmp;
}

static void phone_mini_packet(struct phone_pvt *i)
{
   int res;
   char buf[1024];
   /* Ignore stuff we read... */
   res = read(i->fd, buf, sizeof(buf));
   if (res < 1) {
      ast_log(LOG_WARNING, "Read returned %d: %s\n", res, strerror(errno));
      return;
   }
}

static void phone_check_exception(struct phone_pvt *i)
{
   int offhook=0;
   char digit[2] = {0 , 0};
   union telephony_exception phonee;
   /* XXX Do something XXX */
#if 0
   ast_debug(1, "Exception!\n");
#endif
   phonee.bytes = ioctl(i->fd, PHONE_EXCEPTION);
   if (phonee.bits.dtmf_ready)  {
      digit[0] = ioctl(i->fd, PHONE_GET_DTMF_ASCII);
      if (i->mode == MODE_DIALTONE || i->mode == MODE_FXS || i->mode == MODE_SIGMA) {
         ioctl(i->fd, PHONE_PLAY_STOP);
         ioctl(i->fd, PHONE_REC_STOP);
         ioctl(i->fd, PHONE_CPT_STOP);
         i->dialtone = 0;
         if (strlen(i->ext) < AST_MAX_EXTENSION - 1)
            strncat(i->ext, digit, sizeof(i->ext) - strlen(i->ext) - 1);
         if ((i->mode != MODE_FXS ||
              !(phonee.bytes = ioctl(i->fd, PHONE_EXCEPTION)) ||
              !phonee.bits.dtmf_ready) &&
             ast_exists_extension(NULL, i->context, i->ext, 1, i->cid_num)) {
            /* It's a valid extension in its context, get moving! */
            phone_new(i, AST_STATE_RING, i->context, NULL, NULL);
            /* No need to restart monitor, we are the monitor */
         } else if (!ast_canmatch_extension(NULL, i->context, i->ext, 1, i->cid_num)) {
            /* There is nothing in the specified extension that can match anymore.
               Try the default */
            if (ast_exists_extension(NULL, "default", i->ext, 1, i->cid_num)) {
               /* Check the default, too... */
               phone_new(i, AST_STATE_RING, "default", NULL, NULL);
               /* XXX This should probably be justified better XXX */
            }  else if (!ast_canmatch_extension(NULL, "default", i->ext, 1, i->cid_num)) {
               /* It's not a valid extension, give a busy signal */
               ast_debug(1, "%s can't match anything in %s or default\n", i->ext, i->context);
               ioctl(i->fd, PHONE_BUSY);
               i->cpt = 1;
            }
         }
#if 0
         ast_verbose("Extension is %s\n", i->ext);
#endif
      }
   }
   if (phonee.bits.hookstate) {
      offhook = ioctl(i->fd, PHONE_HOOKSTATE);
      if (offhook) {
         if (i->mode == MODE_IMMEDIATE) {
            phone_new(i, AST_STATE_RING, i->context, NULL, NULL);
         } else if (i->mode == MODE_DIALTONE) {
            ast_module_ref(ast_module_info->self);
            /* Reset the extension */
            i->ext[0] = '\0';
            /* Play the dialtone */
            i->dialtone++;
            ioctl(i->fd, PHONE_PLAY_STOP);
            ioctl(i->fd, PHONE_PLAY_CODEC, ULAW);
            ioctl(i->fd, PHONE_PLAY_START);
            ao2_cleanup(i->lastformat);
            i->lastformat = NULL;
         } else if (i->mode == MODE_SIGMA) {
            ast_module_ref(ast_module_info->self);
            /* Reset the extension */
            i->ext[0] = '\0';
            /* Play the dialtone */
            i->dialtone++;
            ioctl(i->fd, PHONE_DIALTONE);
         }
      } else {
         if (i->dialtone)
            ast_module_unref(ast_module_info->self);
         memset(i->ext, 0, sizeof(i->ext));
         if (i->cpt)
         {
            ioctl(i->fd, PHONE_CPT_STOP);
            i->cpt = 0;
         }
         ioctl(i->fd, PHONE_PLAY_STOP);
         ioctl(i->fd, PHONE_REC_STOP);
         i->dialtone = 0;
         ao2_cleanup(i->lastformat);
         i->lastformat = NULL;
      }
   }
   if (phonee.bits.pstn_ring) {
      ast_verbose("Unit is ringing\n");
      phone_new(i, AST_STATE_RING, i->context, NULL, NULL);
   }
   if (phonee.bits.caller_id)
      ast_verbose("We have caller ID\n");


}

static void *do_monitor(void *data)
{
   struct pollfd *fds = NULL;
   int nfds = 0, inuse_fds = 0, res;
   struct phone_pvt *i;
   int tonepos = 0;
   /* The tone we're playing this round */
   struct timeval to = { 0, 0 };
   int dotone;
   /* This thread monitors all the frame relay interfaces which are not yet in use
      (and thus do not have a separate thread) indefinitely */
   while (monitor) {
      /* Don't let anybody kill us right away.  Nobody should lock the interface list
         and wait for the monitor list, but the other way around is okay. */
      /* Lock the interface list */
      if (ast_mutex_lock(&iflock)) {
         ast_log(LOG_ERROR, "Unable to grab interface lock\n");
         return NULL;
      }
      /* Build the stuff we're going to select on, that is the socket of every
         phone_pvt that does not have an associated owner channel */
      i = iflist;
      dotone = 0;
      inuse_fds = 0;
      for (i = iflist; i; i = i->next) {
         if (!i->owner) {
            /* This needs to be watched, as it lacks an owner */
            if (inuse_fds == nfds) {
               void *tmp = ast_realloc(fds, (nfds + 1) * sizeof(*fds));
               if (!tmp) {
                  /* Avoid leaking */
                  continue;
               }
               fds = tmp;
               nfds++;
            }
            fds[inuse_fds].fd = i->fd;
            fds[inuse_fds].events = POLLIN | POLLERR;
            fds[inuse_fds].revents = 0;
            inuse_fds++;

            if (i->dialtone && i->mode != MODE_SIGMA) {
               /* Remember we're going to have to come back and play
                  more dialtones */
               if (ast_tvzero(to)) {
                  /* If we're due for a dialtone, play one */
                  if (write(i->fd, DialTone + tonepos, 240) != 240) {
                     ast_log(LOG_WARNING, "Dial tone write error\n");
                  }
               }
               dotone++;
            }
         }
      }
      /* Okay, now that we know what to do, release the interface lock */
      ast_mutex_unlock(&iflock);

      /* Wait indefinitely for something to happen */
      if (dotone && i && i->mode != MODE_SIGMA) {
         /* If we're ready to recycle the time, set it to 30 ms */
         tonepos += 240;
         if (tonepos >= sizeof(DialTone)) {
            tonepos = 0;
         }
         if (ast_tvzero(to)) {
            to = ast_tv(0, 30000);
         }
         res = ast_poll2(fds, inuse_fds, &to);
      } else {
         res = ast_poll(fds, inuse_fds, -1);
         to = ast_tv(0, 0);
         tonepos = 0;
      }
      /* Okay, select has finished.  Let's see what happened.  */
      if (res < 0) {
         ast_debug(1, "poll returned %d: %s\n", res, strerror(errno));
         continue;
      }
      /* If there are no fd's changed, just continue, it's probably time
         to play some more dialtones */
      if (!res) {
         continue;
      }
      /* Alright, lock the interface list again, and let's look and see what has
         happened */
      if (ast_mutex_lock(&iflock)) {
         ast_log(LOG_WARNING, "Unable to lock the interface list\n");
         continue;
      }

      for (i = iflist; i; i = i->next) {
         int j;
         /* Find the record */
         for (j = 0; j < inuse_fds; j++) {
            if (fds[j].fd == i->fd) {
               break;
            }
         }

         /* Not found? */
         if (j == inuse_fds) {
            continue;
         }

         if (fds[j].revents & POLLIN) {
            if (i->owner) {
               continue;
            }
            phone_mini_packet(i);
         }
         if (fds[j].revents & POLLERR) {
            if (i->owner) {
               continue;
            }
            phone_check_exception(i);
         }
      }
      ast_mutex_unlock(&iflock);
   }
   return NULL;
}

static int restart_monitor()
{
   /* If we're supposed to be stopped -- stay stopped */
   if (monitor_thread == AST_PTHREADT_STOP)
      return 0;
   if (ast_mutex_lock(&monlock)) {
      ast_log(LOG_WARNING, "Unable to lock monitor\n");
      return -1;
   }
   if (monitor_thread == pthread_self()) {
      ast_mutex_unlock(&monlock);
      ast_log(LOG_WARNING, "Cannot kill myself\n");
      return -1;
   }
   if (monitor_thread != AST_PTHREADT_NULL) {
      if (ast_mutex_lock(&iflock)) {
         ast_mutex_unlock(&monlock);
         ast_log(LOG_WARNING, "Unable to lock the interface list\n");
         return -1;
      }
      monitor = 0;
      while (pthread_kill(monitor_thread, SIGURG) == 0)
         sched_yield();
      pthread_join(monitor_thread, NULL);
      ast_mutex_unlock(&iflock);
   }
   monitor = 1;
   /* Start a new monitor */
   if (ast_pthread_create_background(&monitor_thread, NULL, do_monitor, NULL) < 0) {
      ast_mutex_unlock(&monlock);
      ast_log(LOG_ERROR, "Unable to start monitor thread.\n");
      return -1;
   }
   ast_mutex_unlock(&monlock);
   return 0;
}

static struct phone_pvt *mkif(const char *iface, int mode, int txgain, int rxgain)
{
   /* Make a phone_pvt structure for this interface */
   struct phone_pvt *tmp;

   tmp = ast_calloc(1, sizeof(*tmp));
   if (tmp) {
      tmp->fd = open(iface, O_RDWR);
      if (tmp->fd < 0) {
         ast_log(LOG_WARNING, "Unable to open '%s'\n", iface);
         ast_free(tmp);
         return NULL;
      }
      if (mode == MODE_FXO) {
         if (ioctl(tmp->fd, IXJCTL_PORT, PORT_PSTN)) {
            ast_debug(1, "Unable to set port to PSTN\n");
         }
      } else {
         if (ioctl(tmp->fd, IXJCTL_PORT, PORT_POTS))
             if (mode != MODE_FXS)
                  ast_debug(1, "Unable to set port to POTS\n");
      }
      ioctl(tmp->fd, PHONE_PLAY_STOP);
      ioctl(tmp->fd, PHONE_REC_STOP);
      ioctl(tmp->fd, PHONE_RING_STOP);
      ioctl(tmp->fd, PHONE_CPT_STOP);
      if (ioctl(tmp->fd, PHONE_PSTN_SET_STATE, PSTN_ON_HOOK))
         ast_debug(1, "ioctl(PHONE_PSTN_SET_STATE) failed on %s (%s)\n",iface, strerror(errno));
      if (echocancel != AEC_OFF)
         ioctl(tmp->fd, IXJCTL_AEC_START, echocancel);
      if (silencesupression)
         tmp->silencesupression = 1;
#ifdef PHONE_VAD
      ioctl(tmp->fd, PHONE_VAD, tmp->silencesupression);
#endif
      tmp->mode = mode;
      ast_fd_set_flags(tmp->fd, O_NONBLOCK);
      tmp->owner = NULL;
      ao2_cleanup(tmp->lastformat);
      tmp->lastformat = NULL;
      ao2_cleanup(tmp->lastinput);
      tmp->lastinput = NULL;
      tmp->ministate = 0;
      memset(tmp->ext, 0, sizeof(tmp->ext));
      ast_copy_string(tmp->language, language, sizeof(tmp->language));
      ast_copy_string(tmp->dev, iface, sizeof(tmp->dev));
      ast_copy_string(tmp->context, context, sizeof(tmp->context));
      tmp->next = NULL;
      tmp->obuflen = 0;
      tmp->dialtone = 0;
      tmp->cpt = 0;
      ast_copy_string(tmp->cid_num, cid_num, sizeof(tmp->cid_num));
      ast_copy_string(tmp->cid_name, cid_name, sizeof(tmp->cid_name));
      tmp->txgain = txgain;
      ioctl(tmp->fd, PHONE_PLAY_VOLUME, tmp->txgain);
      tmp->rxgain = rxgain;
      ioctl(tmp->fd, PHONE_REC_VOLUME, tmp->rxgain);
   }
   return tmp;
}

static struct ast_channel *phone_request(const char *type, struct ast_format_cap *cap, const struct ast_assigned_ids *assignedids, const struct ast_channel *requestor, const char *data, int *cause)
{
   struct phone_pvt *p;
   struct ast_channel *tmp = NULL;
   const char *name = data;

   /* Search for an unowned channel */
   if (ast_mutex_lock(&iflock)) {
      ast_log(LOG_ERROR, "Unable to lock interface list???\n");
      return NULL;
   }
   p = iflist;
   while(p) {
      if (p->mode == MODE_FXS || (ast_format_cap_iscompatible(cap, phone_tech.capabilities))) {
         size_t length = strlen(p->dev + 5);
         if (strncmp(name, p->dev + 5, length) == 0 &&
             !isalnum(name[length])) {
             if (!p->owner) {
                     tmp = phone_new(p, AST_STATE_DOWN, p->context, assignedids, requestor);
                     break;
                } else
                     *cause = AST_CAUSE_BUSY;
            }
      }
      p = p->next;
   }
   ast_mutex_unlock(&iflock);
   restart_monitor();
   if (tmp == NULL) {
      if (!(ast_format_cap_iscompatible(cap, phone_tech.capabilities))) {
         struct ast_str *codec_buf = ast_str_alloca(AST_FORMAT_CAP_NAMES_LEN);
         ast_log(LOG_NOTICE, "Asked to get a channel of unsupported format '%s'\n",
            ast_format_cap_get_names(cap, &codec_buf));
         return NULL;
      }
   }
   return tmp;
}

/* parse gain value from config file */
static int parse_gain_value(const char *gain_type, const char *value)
{
   float gain;

   /* try to scan number */
   if (sscanf(value, "%30f", &gain) != 1)
   {
      ast_log(LOG_ERROR, "Invalid %s value '%s' in '%s' config\n",
         value, gain_type, config);
      return DEFAULT_GAIN;
   }

   /* multiplicate gain by 1.0 gain value */
   gain = gain * (float)DEFAULT_GAIN;

   /* percentage? */
   if (value[strlen(value) - 1] == '%')
      return (int)(gain / (float)100);

   return (int)gain;
}

static int __unload_module(void)
{
   struct phone_pvt *p, *pl;
   /* First, take us out of the channel loop */
   if (cur_tech)
      ast_channel_unregister(cur_tech);
   if (!ast_mutex_lock(&iflock)) {
      /* Hangup all interfaces if they have an owner */
      p = iflist;
      while(p) {
         if (p->owner)
            ast_softhangup(p->owner, AST_SOFTHANGUP_APPUNLOAD);
         p = p->next;
      }
      iflist = NULL;
      ast_mutex_unlock(&iflock);
   } else {
      ast_log(LOG_WARNING, "Unable to lock the monitor\n");
      return -1;
   }
   if (!ast_mutex_lock(&monlock)) {
      if (monitor_thread > AST_PTHREADT_NULL) {
         monitor = 0;
         while (pthread_kill(monitor_thread, SIGURG) == 0)
            sched_yield();
         pthread_join(monitor_thread, NULL);
      }
      monitor_thread = AST_PTHREADT_STOP;
      ast_mutex_unlock(&monlock);
   } else {
      ast_log(LOG_WARNING, "Unable to lock the monitor\n");
      return -1;
   }

   if (!ast_mutex_lock(&iflock)) {
      /* Destroy all the interfaces and free their memory */
      p = iflist;
      while(p) {
         /* Close the socket, assuming it's real */
         if (p->fd > -1)
            close(p->fd);
         pl = p;
         p = p->next;
         /* Free associated memory */
         ast_free(pl);
      }
      iflist = NULL;
      ast_mutex_unlock(&iflock);
   } else {
      ast_log(LOG_WARNING, "Unable to lock the monitor\n");
      return -1;
   }

   ao2_ref(phone_tech.capabilities, -1);
   ao2_ref(phone_tech_fxs.capabilities, -1);
   ao2_ref(prefcap, -1);

   return 0;
}

static int unload_module(void)
{
   return __unload_module();
}

static int load_module(void)
{
   struct ast_config *cfg;
   struct ast_variable *v;
   struct phone_pvt *tmp;
   int mode = MODE_IMMEDIATE;
   int txgain = DEFAULT_GAIN, rxgain = DEFAULT_GAIN; /* default gain 1.0 */
   struct ast_flags config_flags = { 0 };

   if (!(phone_tech.capabilities = ast_format_cap_alloc(AST_FORMAT_CAP_FLAG_DEFAULT))) {
      return AST_MODULE_LOAD_DECLINE;
   }

   ast_format_cap_append(phone_tech.capabilities, ast_format_g723, 0);
   ast_format_cap_append(phone_tech.capabilities, ast_format_slin, 0);
   ast_format_cap_append(phone_tech.capabilities, ast_format_ulaw, 0);
   ast_format_cap_append(phone_tech.capabilities, ast_format_g729, 0);

   if (!(prefcap = ast_format_cap_alloc(AST_FORMAT_CAP_FLAG_DEFAULT))) {
      return AST_MODULE_LOAD_DECLINE;
   }
   ast_format_cap_append_from_cap(prefcap, phone_tech.capabilities, AST_MEDIA_TYPE_UNKNOWN);
   if (!(phone_tech_fxs.capabilities = ast_format_cap_alloc(AST_FORMAT_CAP_FLAG_DEFAULT))) {
      return AST_MODULE_LOAD_DECLINE;
   }

   if ((cfg = ast_config_load(config, config_flags)) == CONFIG_STATUS_FILEINVALID) {
      ast_log(LOG_ERROR, "Config file %s is in an invalid format.  Aborting.\n", config);
      return AST_MODULE_LOAD_DECLINE;
   }

   /* We *must* have a config file otherwise stop immediately */
   if (!cfg) {
      ast_log(LOG_ERROR, "Unable to load config %s\n", config);
      return AST_MODULE_LOAD_DECLINE;
   }
   if (ast_mutex_lock(&iflock)) {
      /* It's a little silly to lock it, but we mind as well just to be sure */
      ast_log(LOG_ERROR, "Unable to lock interface list???\n");
      return AST_MODULE_LOAD_DECLINE;
   }
   v = ast_variable_browse(cfg, "interfaces");
   while(v) {
      /* Create the interface list */
      if (!strcasecmp(v->name, "device")) {
            tmp = mkif(v->value, mode, txgain, rxgain);
            if (tmp) {
               tmp->next = iflist;
               iflist = tmp;

            } else {
               ast_log(LOG_ERROR, "Unable to register channel '%s'\n", v->value);
               ast_config_destroy(cfg);
               ast_mutex_unlock(&iflock);
               __unload_module();
               return AST_MODULE_LOAD_DECLINE;
            }
      } else if (!strcasecmp(v->name, "silencesupression")) {
         silencesupression = ast_true(v->value);
      } else if (!strcasecmp(v->name, "language")) {
         ast_copy_string(language, v->value, sizeof(language));
      } else if (!strcasecmp(v->name, "callerid")) {
         ast_callerid_split(v->value, cid_name, sizeof(cid_name), cid_num, sizeof(cid_num));
      } else if (!strcasecmp(v->name, "mode")) {
         if (!strncasecmp(v->value, "di", 2))
            mode = MODE_DIALTONE;
         else if (!strncasecmp(v->value, "sig", 3))
            mode = MODE_SIGMA;
         else if (!strncasecmp(v->value, "im", 2))
            mode = MODE_IMMEDIATE;
         else if (!strncasecmp(v->value, "fxs", 3)) {
            mode = MODE_FXS;
            ast_format_cap_remove_by_type(prefcap, AST_MEDIA_TYPE_AUDIO); /* All non-voice */
         }
         else if (!strncasecmp(v->value, "fx", 2))
            mode = MODE_FXO;
         else
            ast_log(LOG_WARNING, "Unknown mode: %s\n", v->value);
      } else if (!strcasecmp(v->name, "context")) {
         ast_copy_string(context, v->value, sizeof(context));
      } else if (!strcasecmp(v->name, "format")) {
         if (!strcasecmp(v->value, "g729")) {
            ast_format_cap_remove_by_type(prefcap, AST_MEDIA_TYPE_UNKNOWN);
            ast_format_cap_append(prefcap, ast_format_g729, 0);
         } else if (!strcasecmp(v->value, "g723.1")) {
            ast_format_cap_remove_by_type(prefcap, AST_MEDIA_TYPE_UNKNOWN);
            ast_format_cap_append(prefcap, ast_format_g723, 0);
         } else if (!strcasecmp(v->value, "slinear")) {
            if (mode == MODE_FXS) {
               ast_format_cap_append(prefcap, ast_format_slin, 0);
            } else {
               ast_format_cap_remove_by_type(prefcap, AST_MEDIA_TYPE_UNKNOWN);
               ast_format_cap_append(prefcap, ast_format_slin, 0);
            }
         } else if (!strcasecmp(v->value, "ulaw")) {
            ast_format_cap_remove_by_type(prefcap, AST_MEDIA_TYPE_UNKNOWN);
            ast_format_cap_append(prefcap, ast_format_ulaw, 0);
         } else
            ast_log(LOG_WARNING, "Unknown format '%s'\n", v->value);
      } else if (!strcasecmp(v->name, "echocancel")) {
         if (!strcasecmp(v->value, "off")) {
            echocancel = AEC_OFF;
         } else if (!strcasecmp(v->value, "low")) {
            echocancel = AEC_LOW;
         } else if (!strcasecmp(v->value, "medium")) {
            echocancel = AEC_MED;
         } else if (!strcasecmp(v->value, "high")) {
            echocancel = AEC_HIGH;
         } else
            ast_log(LOG_WARNING, "Unknown echo cancellation '%s'\n", v->value);
      } else if (!strcasecmp(v->name, "txgain")) {
         txgain = parse_gain_value(v->name, v->value);
      } else if (!strcasecmp(v->name, "rxgain")) {
         rxgain = parse_gain_value(v->name, v->value);
      }
      v = v->next;
   }
   ast_mutex_unlock(&iflock);

   if (mode == MODE_FXS) {
      ast_format_cap_append_from_cap(phone_tech_fxs.capabilities, prefcap, AST_MEDIA_TYPE_UNKNOWN);
      cur_tech = &phone_tech_fxs;
   } else
      cur_tech = (struct ast_channel_tech *) &phone_tech;

   /* Make sure we can register our Adtranphone channel type */

   if (ast_channel_register(cur_tech)) {
      ast_log(LOG_ERROR, "Unable to register channel class 'Phone'\n");
      ast_config_destroy(cfg);
      __unload_module();
      return AST_MODULE_LOAD_DECLINE;
   }
   ast_config_destroy(cfg);
   /* And start the monitor for the first time */
   restart_monitor();
   return AST_MODULE_LOAD_SUCCESS;
}

AST_MODULE_INFO_STANDARD_DEPRECATED(ASTERISK_GPL_KEY, "Linux Telephony API Support");