Version 0.1.11 from FTP
authorMark Spencer <markster@digium.com>
Tue, 19 Feb 2002 20:14:14 +0000 (20:14 +0000)
committerMark Spencer <markster@digium.com>
Tue, 19 Feb 2002 20:14:14 +0000 (20:14 +0000)
git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@416 65c4cc65-6c06-0410-ace0-fbb531ad65f3

channels/chan_alsa.c [new file with mode: 0755]

diff --git a/channels/chan_alsa.c b/channels/chan_alsa.c
new file mode 100755 (executable)
index 0000000..56fca5c
--- /dev/null
@@ -0,0 +1,1113 @@
+/*
+ * Asterisk -- A telephony toolkit for Linux.
+ *
+ * Copyright (C) 2002, Linux Support Services
+ *
+ * By Matthew Fredrickson <creslin@linux-support.net>
+ *
+ * This program is free software, distributed under the terms of
+ * the GNU General Public License
+ */
+
+#include <asterisk/frame.h>
+#include <asterisk/logger.h>
+#include <asterisk/channel.h>
+#include <asterisk/module.h>
+#include <asterisk/channel_pvt.h>
+#include <asterisk/options.h>
+#include <asterisk/pbx.h>
+#include <asterisk/config.h>
+#include <asterisk/cli.h>
+#include <unistd.h>
+#include <fcntl.h>
+#include <errno.h>
+#include <sys/ioctl.h>
+#include <sys/time.h>
+#include <string.h>
+#include <stdlib.h>
+#include <stdio.h>
+#include <alsa/asoundlib.h>
+#include "busy.h"
+#include "ringtone.h"
+#include "ring10.h"
+#include "answer.h"
+
+#ifdef ALSA_MONITOR
+#include "alsa-monitor.h"
+#endif
+
+#define DEBUG 0
+/* Which device to use */
+#define ALSA_INDEV "default"
+#define ALSA_OUTDEV "default"
+#define DESIRED_RATE 8000
+
+/* Lets use 160 sample frames, just like GSM.  */
+#define FRAME_SIZE 160
+#define PERIOD_FRAMES 80 /* 80 Frames, at 2 bytes each */
+
+/* When you set the frame size, you have to come up with
+   the right buffer format as well. */
+/* 5 64-byte frames = one frame */
+#define BUFFER_FMT ((buffersize * 10) << 16) | (0x0006);
+
+/* Don't switch between read/write modes faster than every 300 ms */
+#define MIN_SWITCH_TIME 600
+
+static snd_pcm_format_t format = SND_PCM_FORMAT_S16_LE;
+//static int block = O_NONBLOCK;
+static char indevname[50] = ALSA_INDEV;
+static char outdevname[50] = ALSA_OUTDEV;
+
+static struct timeval lasttime;
+
+static int usecnt;
+static int needanswer = 0;
+static int needringing = 0;
+static int needhangup = 0;
+static int silencesuppression = 0;
+static int silencethreshold = 1000;
+
+static char digits[80] = "";
+static char text2send[80] = "";
+
+static pthread_mutex_t usecnt_lock = PTHREAD_MUTEX_INITIALIZER;
+
+static char *type = "Console";
+static char *desc = "ALSA Console Channel Driver";
+static char *tdesc = "ALSA Console Channel Driver";
+static char *config = "alsa.conf";
+
+static char context[AST_MAX_EXTENSION] = "default";
+static char language[MAX_LANGUAGE] = "";
+static char exten[AST_MAX_EXTENSION] = "s";
+
+/* Command pipe */
+static int cmd[2];
+
+int hookstate=0;
+
+static short silence[FRAME_SIZE] = {0, };
+
+struct sound {
+       int ind;
+       short *data;
+       int datalen;
+       int samplen;
+       int silencelen;
+       int repeat;
+};
+
+static struct sound sounds[] = {
+       { AST_CONTROL_RINGING, ringtone, sizeof(ringtone)/2, 16000, 32000, 1 },
+       { AST_CONTROL_BUSY, busy, sizeof(busy)/2, 4000, 4000, 1 },
+       { AST_CONTROL_CONGESTION, busy, sizeof(busy)/2, 2000, 2000, 1 },
+       { AST_CONTROL_RING, ring10, sizeof(ring10)/2, 16000, 32000, 1 },
+       { AST_CONTROL_ANSWER, answer, sizeof(answer)/2, 2200, 0, 0 },
+};
+
+/* Sound command pipe */
+static int sndcmd[2];
+
+static struct chan_alsa_pvt {
+       /* We only have one ALSA structure -- near sighted perhaps, but it
+          keeps this driver as simple as possible -- as it should be. */
+       struct ast_channel *owner;
+       char exten[AST_MAX_EXTENSION];
+       char context[AST_MAX_EXTENSION];
+#if 0
+       snd_pcm_t *card;
+#endif
+       snd_pcm_t *icard, *ocard;
+       
+} alsa;
+
+static int time_has_passed()
+{
+       struct timeval tv;
+       int ms;
+       gettimeofday(&tv, NULL);
+       ms = (tv.tv_sec - lasttime.tv_sec) * 1000 +
+                       (tv.tv_usec - lasttime.tv_usec) / 1000;
+       if (ms > MIN_SWITCH_TIME)
+               return -1;
+       return 0;
+}
+
+/* Number of buffers...  Each is FRAMESIZE/8 ms long.  For example
+   with 160 sample frames, and a buffer size of 3, we have a 60ms buffer, 
+   usually plenty. */
+
+pthread_t sthread;
+
+#define MAX_BUFFER_SIZE 100
+//static int buffersize = 3;
+
+//static int full_duplex = 0;
+
+/* Are we reading or writing (simulated full duplex) */
+//static int readmode = 1;
+
+/* File descriptors for sound device */
+static int readdev = -1;
+static int writedev = -1;
+
+static int autoanswer = 1;
+static int calc_loudness(short *frame)
+{
+       int sum = 0;
+       int x;
+       for (x=0;x<FRAME_SIZE;x++) {
+               if (frame[x] < 0)
+                       sum -= frame[x];
+               else
+                       sum += frame[x];
+       }
+       sum = sum/FRAME_SIZE;
+       return sum;
+}
+
+static int cursound = -1;
+static int sampsent = 0;
+static int silencelen=0;
+static int offset=0;
+static int nosound=0;
+
+static int send_sound(void)
+{
+       short myframe[FRAME_SIZE];
+       int total = FRAME_SIZE;
+       short *frame = NULL;
+       int amt=0;
+       int res;
+       int myoff;
+       snd_pcm_state_t state;
+
+       if (cursound > -1) {
+               res = total;
+               if (sampsent < sounds[cursound].samplen) {
+                       myoff=0;
+                       while(total) {
+                               amt = total;
+                               if (amt > (sounds[cursound].datalen - offset)) 
+                                       amt = sounds[cursound].datalen - offset;
+                               memcpy(myframe + myoff, sounds[cursound].data + offset, amt * 2);
+                               total -= amt;
+                               offset += amt;
+                               sampsent += amt;
+                               myoff += amt;
+                               if (offset >= sounds[cursound].datalen)
+                                       offset = 0;
+                       }
+                       /* Set it up for silence */
+                       if (sampsent >= sounds[cursound].samplen) 
+                               silencelen = sounds[cursound].silencelen;
+                       frame = myframe;
+               } else {
+                       if (silencelen > 0) {
+                               frame = silence;
+                               silencelen -= res;
+                       } else {
+                               if (sounds[cursound].repeat) {
+                                       /* Start over */
+                                       sampsent = 0;
+                                       offset = 0;
+                               } else {
+                                       cursound = -1;
+                                       nosound = 0;
+                               }
+                       return 0;
+                       }
+               }
+               
+               if (res == 0 || !frame) {
+                       return 0;
+               }
+#ifdef ALSA_MONITOR
+               alsa_monitor_write((char *)frame, res * 2);
+#endif         
+               state = snd_pcm_state(alsa.ocard);
+               if (state == SND_PCM_STATE_XRUN) {
+                       snd_pcm_prepare(alsa.ocard);
+               }
+               res = snd_pcm_writei(alsa.ocard, frame, res);
+               if (res > 0)
+                       return 0;
+               return 0;
+       }
+       return 0;
+}
+
+static void *sound_thread(void *unused)
+{
+       fd_set rfds;
+       fd_set wfds;
+       int max;
+       int res;
+       for(;;) {
+               FD_ZERO(&rfds);
+               FD_ZERO(&wfds);
+               max = sndcmd[0];
+               FD_SET(sndcmd[0], &rfds);
+               if (cursound > -1) {
+                       FD_SET(writedev, &wfds);
+                       if (writedev > max)
+                               max = writedev;
+               }
+#ifdef ALSA_MONITOR
+               if (!alsa.owner) {
+                       FD_SET(readdev, &rfds);
+                       if (readdev > max)
+                               max = readdev;
+               }
+#endif
+               res = select(max + 1, &rfds, &wfds, NULL, NULL);
+               if (res < 1) {
+                       ast_log(LOG_WARNING, "select failed: %s\n", strerror(errno));
+                       continue;
+               }
+#ifdef ALSA_MONITOR
+               if (FD_ISSET(readdev, &rfds)) {
+                       /* Keep the pipe going with read audio */
+                       snd_pcm_state_t state;
+                       short buf[FRAME_SIZE];
+                       int r;
+                       
+                       state = snd_pcm_state(alsa.ocard);
+                       if (state == SND_PCM_STATE_XRUN) {
+                               snd_pcm_prepare(alsa.ocard);
+                       }
+                       r = snd_pcm_readi(alsa.icard, buf, FRAME_SIZE);
+                       if (r == -EPIPE) {
+#if DEBUG
+                               ast_log(LOG_ERROR, "XRUN read\n");
+#endif
+                               snd_pcm_prepare(alsa.icard);
+                       } else if (r == -ESTRPIPE) {
+                               ast_log(LOG_ERROR, "-ESTRPIPE\n");
+                               snd_pcm_prepare(alsa.icard);
+                       } else if (r < 0) {
+                               ast_log(LOG_ERROR, "Read error: %s\n", snd_strerror(r));
+                       } else
+                               alsa_monitor_read((char *)buf, r * 2);
+               }               
+#endif         
+               if (FD_ISSET(sndcmd[0], &rfds)) {
+                       read(sndcmd[0], &cursound, sizeof(cursound));
+                       silencelen = 0;
+                       offset = 0;
+                       sampsent = 0;
+               }
+               if (FD_ISSET(writedev, &wfds))
+                       if (send_sound())
+                               ast_log(LOG_WARNING, "Failed to write sound\n");
+       }
+       /* Never reached */
+       return NULL;
+}
+
+static snd_pcm_t *alsa_card_init(char *dev, snd_pcm_stream_t stream)
+{
+       int err;
+       snd_pcm_t *handle = NULL;
+       snd_pcm_hw_params_t *hwparams = NULL;
+       snd_pcm_sw_params_t *swparams = NULL;
+       struct pollfd pfd;
+       int period_size = PERIOD_FRAMES * 4;
+       //int period_bytes = 0;
+       int buffer_size = 0;
+       
+       unsigned int rate = DESIRED_RATE;
+       unsigned int per_min = 1;
+       //unsigned int per_max = 8;
+       snd_pcm_uframes_t start_threshold, stop_threshold;
+
+       err = snd_pcm_open(&handle, dev, stream, O_NONBLOCK);
+       if (err < 0) {
+               ast_log(LOG_ERROR, "snd_pcm_open failed: %s\n", snd_strerror(err));
+               return NULL;
+       } else {
+               ast_log(LOG_DEBUG, "Opening device %s in %s mode\n", dev, (stream == SND_PCM_STREAM_CAPTURE) ? "read" : "write");
+       }
+
+       snd_pcm_hw_params_alloca(&hwparams);
+       snd_pcm_hw_params_any(handle, hwparams);
+
+       err = snd_pcm_hw_params_set_access(handle, hwparams, SND_PCM_ACCESS_RW_INTERLEAVED);
+       if (err < 0) {
+               ast_log(LOG_ERROR, "set_access failed: %s\n", snd_strerror(err));
+       }
+
+       err = snd_pcm_hw_params_set_format(handle, hwparams, format);
+       if (err < 0) {
+               ast_log(LOG_ERROR, "set_format failed: %s\n", snd_strerror(err));
+       }
+
+       err = snd_pcm_hw_params_set_channels(handle, hwparams, 1);
+       if (err < 0) {
+               ast_log(LOG_ERROR, "set_channels failed: %s\n", snd_strerror(err));
+       }
+
+       rate = snd_pcm_hw_params_set_rate_near(handle, hwparams, rate, 0);
+
+       if (rate != DESIRED_RATE) {
+               ast_log(LOG_WARNING, "Rate not correct, requested %d, got %d\n", DESIRED_RATE, rate);
+       }
+
+       err = snd_pcm_hw_params_set_period_size_near(handle, hwparams, period_size, 0);
+       if (err < 0) {
+               ast_log(LOG_ERROR, "period_size(%d frames) is bad: %s\n", period_size, snd_strerror(err));
+       } else {
+               ast_log(LOG_DEBUG, "Period size is %d\n", err);
+       }
+       period_size = err;
+
+       buffer_size = 4096 * 2; //period_size * 16;
+       err = snd_pcm_hw_params_set_buffer_size_near(handle, hwparams, buffer_size);
+       if (err < 0) {
+               ast_log(LOG_WARNING, "Problem setting buffer size of %d: %s\n", buffer_size, snd_strerror(err));
+       } else {
+               ast_log(LOG_DEBUG, "Buffer size is set to %d frames\n", err);
+       }
+       buffer_size = err;
+
+       err = snd_pcm_hw_params_set_periods_min(handle, hwparams, &per_min, 0);
+       if (err < 0) {
+               ast_log(LOG_ERROR, "periods_min: %s\n", snd_strerror(err));
+       }
+
+#if 0
+       err = snd_pcm_hw_params_set_periods_max(handle, hwparams, &per_max, 0);
+       if (err < 0) {
+               ast_log(LOG_ERROR, "periods_max: %s\n", snd_strerror(err));
+       }
+#endif
+
+       err = snd_pcm_hw_params(handle, hwparams);
+       if (err < 0) {
+               ast_log(LOG_ERROR, "Couldn't set the new hw params: %s\n", snd_strerror(err));
+       }
+
+       snd_pcm_sw_params_alloca(&swparams);
+       snd_pcm_sw_params_current(handle, swparams);
+
+#if 1
+       if (stream == SND_PCM_STREAM_PLAYBACK) {
+               start_threshold = period_size;
+       } else {
+               start_threshold = 1;
+       }
+
+       err = snd_pcm_sw_params_set_start_threshold(handle, swparams, start_threshold);
+       if (err < 0) {
+               ast_log(LOG_ERROR, "start threshold: %s\n", snd_strerror(err));
+       }
+#endif
+
+#if 1
+       if (stream == SND_PCM_STREAM_PLAYBACK) {
+               stop_threshold = buffer_size;
+       } else {
+               stop_threshold = buffer_size;
+       }
+       err = snd_pcm_sw_params_set_stop_threshold(handle, swparams, stop_threshold);
+       if (err < 0) {
+               ast_log(LOG_ERROR, "stop threshold: %s\n", snd_strerror(err));
+       }
+#endif
+#if 0
+       err = snd_pcm_sw_params_set_xfer_align(handle, swparams, PERIOD_FRAMES);
+       if (err < 0) {
+               ast_log(LOG_ERROR, "Unable to set xfer alignment: %s\n", snd_strerror(err));
+       }
+#endif
+
+       err = snd_pcm_sw_params_set_silence_threshold(handle, swparams, buffer_size);
+       if (err < 0) {
+               ast_log(LOG_ERROR, "Unable to set silence threshold: %s\n", snd_strerror(err));
+       }
+
+       err = snd_pcm_sw_params(handle, swparams);
+       if (err < 0) {
+               ast_log(LOG_ERROR, "sw_params: %s\n", snd_strerror(err));
+       }
+
+       err = snd_pcm_poll_descriptors_count(handle);
+       if (err <= 0) {
+               ast_log(LOG_ERROR, "Unable to get a poll descriptors count, error is %s\n", snd_strerror(err));
+       }
+
+       if (err != 1) {
+               ast_log(LOG_DEBUG, "Can't handle more than one device\n");
+       }
+
+       snd_pcm_poll_descriptors(handle, &pfd, err);
+       ast_log(LOG_DEBUG, "Acquired fd %d from the poll descriptor\n", pfd.fd);
+
+       if (stream == SND_PCM_STREAM_CAPTURE)
+               readdev = pfd.fd;
+       else
+               writedev = pfd.fd;
+
+       return handle;
+}
+
+static int soundcard_init()
+{
+       alsa.icard = alsa_card_init(indevname, SND_PCM_STREAM_CAPTURE);
+       alsa.ocard = alsa_card_init(outdevname, SND_PCM_STREAM_PLAYBACK);
+
+       if (!alsa.icard || !alsa.ocard) {
+               ast_log(LOG_ERROR, "Problem opening alsa I/O devices\n");
+               return -1;
+       }
+
+       return readdev;
+}
+
+static int alsa_digit(struct ast_channel *c, char digit)
+{
+       ast_verbose( " << Console Received digit %c >> \n", digit);
+       return 0;
+}
+
+static int alsa_text(struct ast_channel *c, char *text)
+{
+       ast_verbose( " << Console Received text %s >> \n", text);
+       return 0;
+}
+
+static int alsa_call(struct ast_channel *c, char *dest, int timeout)
+{
+       int res = 3;
+       ast_verbose( " << Call placed to '%s' on console >> \n", dest);
+       if (autoanswer) {
+               ast_verbose( " << Auto-answered >> \n" );
+               needanswer = 1;
+       } else {
+               ast_verbose( " << Type 'answer' to answer, or use 'autoanswer' for future calls >> \n");
+               needringing = 1;
+               write(sndcmd[1], &res, sizeof(res));
+       }
+       return 0;
+}
+
+static void answer_sound(void)
+{
+       int res;
+       nosound = 1;
+       res = 4;
+       write(sndcmd[1], &res, sizeof(res));
+       
+}
+
+static int alsa_answer(struct ast_channel *c)
+{
+       ast_verbose( " << Console call has been answered >> \n");
+       answer_sound();
+       c->state = AST_STATE_UP;
+       cursound = -1;
+       return 0;
+}
+
+static int alsa_hangup(struct ast_channel *c)
+{
+       int res;
+       cursound = -1;
+       c->pvt->pvt = NULL;
+       alsa.owner = NULL;
+       ast_verbose( " << Hangup on console >> \n");
+       ast_pthread_mutex_lock(&usecnt_lock);
+       usecnt--;
+       ast_pthread_mutex_unlock(&usecnt_lock);
+       needhangup = 0;
+       needanswer = 0;
+       if (hookstate) {
+               res = 2;
+               write(sndcmd[1], &res, sizeof(res));
+       }
+       return 0;
+}
+
+#if 0
+static int soundcard_writeframe(short *data)
+{      
+       /* Write an exactly FRAME_SIZE sized of frame */
+       static int bufcnt = 0;
+       static short buffer[FRAME_SIZE * MAX_BUFFER_SIZE * 5];
+       struct audio_buf_info info;
+       int res;
+       int fd = sounddev;
+       static int warned=0;
+       if (ioctl(fd, SNDCTL_DSP_GETOSPACE, &info)) {
+               if (!warned)
+                       ast_log(LOG_WARNING, "Error reading output space\n");
+               bufcnt = buffersize;
+               warned++;
+       }
+       if ((info.fragments >= buffersize * 5) && (bufcnt == buffersize)) {
+               /* We've run out of stuff, buffer again */
+               bufcnt = 0;
+       }
+       if (bufcnt == buffersize) {
+               /* Write sample immediately */
+               res = write(fd, ((void *)data), FRAME_SIZE * 2);
+       } else {
+               /* Copy the data into our buffer */
+               res = FRAME_SIZE * 2;
+               memcpy(buffer + (bufcnt * FRAME_SIZE), data, FRAME_SIZE * 2);
+               bufcnt++;
+               if (bufcnt == buffersize) {
+                       res = write(fd, ((void *)buffer), FRAME_SIZE * 2 * buffersize);
+               }
+       }
+       return res;
+}
+#endif
+
+static int alsa_write(struct ast_channel *chan, struct ast_frame *f)
+{
+       int res;
+       static char sizbuf[8000];
+       static int sizpos = 0;
+       int len = sizpos;
+       int pos;
+       //size_t frames = 0;
+       snd_pcm_state_t state;
+       /* Immediately return if no sound is enabled */
+       if (nosound)
+               return 0;
+       /* Stop any currently playing sound */
+       if (cursound != -1) {
+               snd_pcm_drop(alsa.ocard);
+               snd_pcm_prepare(alsa.ocard);
+               cursound = -1;
+       }
+       
+
+       /* We have to digest the frame in 160-byte portions */
+       if (f->datalen > sizeof(sizbuf) - sizpos) {
+               ast_log(LOG_WARNING, "Frame too large\n");
+               return -1;
+       }
+       memcpy(sizbuf + sizpos, f->data, f->datalen);
+       len += f->datalen;
+       pos = 0;
+#ifdef ALSA_MONITOR
+       alsa_monitor_write(sizbuf, len);
+#endif
+       state = snd_pcm_state(alsa.ocard);
+       if (state == SND_PCM_STATE_XRUN) {
+               snd_pcm_prepare(alsa.ocard);
+       }
+       res = snd_pcm_writei(alsa.ocard, sizbuf, len/2);
+       if (res == -EPIPE) {
+#if DEBUG
+               ast_log(LOG_DEBUG, "XRUN write\n");
+#endif
+               snd_pcm_prepare(alsa.ocard);
+               res = snd_pcm_writei(alsa.ocard, sizbuf, len/2);
+               if (res != len/2) {
+                       ast_log(LOG_ERROR, "Write error: %s\n", snd_strerror(res));
+                       return -1;
+               } else if (res < 0) {
+                       ast_log(LOG_ERROR, "Write error %s\n", snd_strerror(res));
+                       return -1;
+               }
+       } else {
+               if (res == -ESTRPIPE) {
+                       ast_log(LOG_ERROR, "You've got some big problems\n");
+               }
+       }
+
+       return 0;
+}
+
+
+static struct ast_frame *alsa_read(struct ast_channel *chan)
+{
+       static struct ast_frame f;
+       static short __buf[FRAME_SIZE + AST_FRIENDLY_OFFSET/2];
+       short *buf;
+       static int readpos = 0;
+       static int left = FRAME_SIZE;
+       int res;
+       int b;
+       int nonull=0;
+       snd_pcm_state_t state;
+       int r = 0;
+       int off = 0;
+
+       /* Acknowledge any pending cmd */
+       res = read(cmd[0], &b, sizeof(b));
+       if (res > 0)
+               nonull = 1;
+       
+       f.frametype = AST_FRAME_NULL;
+       f.subclass = 0;
+       f.timelen = 0;
+       f.datalen = 0;
+       f.data = NULL;
+       f.offset = 0;
+       f.src = type;
+       f.mallocd = 0;
+       
+       if (needringing) {
+               f.frametype = AST_FRAME_CONTROL;
+               f.subclass = AST_CONTROL_RINGING;
+               needringing = 0;
+               return &f;
+       }
+       
+       if (needhangup) {
+               needhangup = 0;
+               return NULL;
+       }
+       if (strlen(text2send)) {
+               f.frametype = AST_FRAME_TEXT;
+               f.subclass = 0;
+               f.data = text2send;
+               f.datalen = strlen(text2send);
+               strcpy(text2send,"");
+               return &f;
+       }
+       if (strlen(digits)) {
+               f.frametype = AST_FRAME_DTMF;
+               f.subclass = digits[0];
+               for (res=0;res<strlen(digits);res++)
+                       digits[res] = digits[res + 1];
+               return &f;
+       }
+       
+       if (needanswer) {
+               needanswer = 0;
+               f.frametype = AST_FRAME_CONTROL;
+               f.subclass = AST_CONTROL_ANSWER;
+               chan->state = AST_STATE_UP;
+               return &f;
+       }
+       
+       if (nonull)
+               return &f;
+               
+       
+       state = snd_pcm_state(alsa.ocard);
+       if (state == SND_PCM_STATE_XRUN) {
+               snd_pcm_prepare(alsa.ocard);
+       }
+
+       buf = __buf + AST_FRIENDLY_OFFSET/2;
+
+       r = snd_pcm_readi(alsa.icard, buf + readpos, left);
+       if (r == -EPIPE) {
+#if DEBUG
+               ast_log(LOG_ERROR, "XRUN read\n");
+#endif
+               snd_pcm_prepare(alsa.icard);
+       } else if (r == -ESTRPIPE) {
+               ast_log(LOG_ERROR, "-ESTRPIPE\n");
+               snd_pcm_prepare(alsa.icard);
+       } else if (r < 0) {
+               ast_log(LOG_ERROR, "Read error: %s\n", snd_strerror(r));
+               return NULL;
+       } else if (r >= 0) {
+               off -= r;
+       }
+       /* Update positions */
+       readpos += r;
+       left -= r;
+
+       if (readpos >= FRAME_SIZE) {
+               /* A real frame */
+               readpos = 0;
+               left = FRAME_SIZE;
+               if (chan->state != AST_STATE_UP) {
+                       /* Don't transmit unless it's up */
+                       return &f;
+               }
+               f.frametype = AST_FRAME_VOICE;
+               f.subclass = AST_FORMAT_SLINEAR;
+               f.timelen = FRAME_SIZE / 8;
+               f.datalen = FRAME_SIZE * 2;
+               f.data = buf;
+               f.offset = AST_FRIENDLY_OFFSET;
+               f.src = type;
+               f.mallocd = 0;
+#ifdef ALSA_MONITOR
+               alsa_monitor_read((char *)buf, FRAME_SIZE * 2);
+#endif         
+
+#if 0
+               { static int fd = -1;
+                 if (fd < 0)
+                       fd = open("output.raw", O_RDWR | O_TRUNC | O_CREAT);
+                 write(fd, f.data, f.datalen);
+               }
+#endif         
+       }
+       return &f;
+}
+
+static int alsa_fixup(struct ast_channel *oldchan, struct ast_channel *newchan)
+{
+       struct chan_alsa_pvt *p = newchan->pvt->pvt;
+       p->owner = newchan;
+       return 0;
+}
+
+static int alsa_indicate(struct ast_channel *chan, int cond)
+{
+       int res;
+       switch(cond) {
+       case AST_CONTROL_BUSY:
+               res = 1;
+               break;
+       case AST_CONTROL_CONGESTION:
+               res = 2;
+               break;
+       case AST_CONTROL_RINGING:
+               res = 0;
+               break;
+       default:
+               ast_log(LOG_WARNING, "Don't know how to display condition %d on %s\n", cond, chan->name);
+               return -1;
+       }
+       if (res > -1) {
+               write(sndcmd[1], &res, sizeof(res));
+       }
+       return 0;       
+}
+
+static struct ast_channel *alsa_new(struct chan_alsa_pvt *p, int state)
+{
+       struct ast_channel *tmp;
+       tmp = ast_channel_alloc();
+       if (tmp) {
+               snprintf(tmp->name, sizeof(tmp->name), "ALSA/%s", indevname);
+               tmp->type = type;
+               tmp->fds[0] = readdev;
+               tmp->fds[1] = cmd[0];
+               tmp->nativeformats = AST_FORMAT_SLINEAR;
+               tmp->pvt->pvt = p;
+               tmp->pvt->send_digit = alsa_digit;
+               tmp->pvt->send_text = alsa_text;
+               tmp->pvt->hangup = alsa_hangup;
+               tmp->pvt->answer = alsa_answer;
+               tmp->pvt->read = alsa_read;
+               tmp->pvt->call = alsa_call;
+               tmp->pvt->write = alsa_write;
+               tmp->pvt->indicate = alsa_indicate;
+               tmp->pvt->fixup = alsa_fixup;
+               if (strlen(p->context))
+                       strncpy(tmp->context, p->context, sizeof(tmp->context)-1);
+               if (strlen(p->exten))
+                       strncpy(tmp->exten, p->exten, sizeof(tmp->exten)-1);
+               if (strlen(language))
+                       strncpy(tmp->language, language, sizeof(tmp->language)-1);
+               p->owner = tmp;
+               tmp->state = state;
+               ast_pthread_mutex_lock(&usecnt_lock);
+               usecnt++;
+               ast_pthread_mutex_unlock(&usecnt_lock);
+               ast_update_use_count();
+               if (state != AST_STATE_DOWN) {
+                       if (ast_pbx_start(tmp)) {
+                               ast_log(LOG_WARNING, "Unable to start PBX on %s\n", tmp->name);
+                               ast_hangup(tmp);
+                               tmp = NULL;
+                       }
+               }
+       }
+       return tmp;
+}
+
+static struct ast_channel *alsa_request(char *type, int format, void *data)
+{
+       int oldformat = format;
+       struct ast_channel *tmp;
+       format &= AST_FORMAT_SLINEAR;
+       if (!format) {
+               ast_log(LOG_NOTICE, "Asked to get a channel of format '%d'\n", oldformat);
+               return NULL;
+       }
+       if (alsa.owner) {
+               ast_log(LOG_NOTICE, "Already have a call on the ALSA channel\n");
+               return NULL;
+       }
+       tmp= alsa_new(&alsa, AST_STATE_DOWN);
+       if (!tmp) {
+               ast_log(LOG_WARNING, "Unable to create new ALSA channel\n");
+       }
+       return tmp;
+}
+
+static int console_autoanswer(int fd, int argc, char *argv[])
+{
+       if ((argc != 1) && (argc != 2))
+               return RESULT_SHOWUSAGE;
+       if (argc == 1) {
+               ast_cli(fd, "Auto answer is %s.\n", autoanswer ? "on" : "off");
+               return RESULT_SUCCESS;
+       } else {
+               if (!strcasecmp(argv[1], "on"))
+                       autoanswer = -1;
+               else if (!strcasecmp(argv[1], "off"))
+                       autoanswer = 0;
+               else
+                       return RESULT_SHOWUSAGE;
+       }
+       return RESULT_SUCCESS;
+}
+
+static char *autoanswer_complete(char *line, char *word, int pos, int state)
+{
+#ifndef MIN
+#define MIN(a,b) ((a) < (b) ? (a) : (b))
+#endif
+       switch(state) {
+       case 0:
+               if (strlen(word) && !strncasecmp(word, "on", MIN(strlen(word), 2)))
+                       return strdup("on");
+       case 1:
+               if (strlen(word) && !strncasecmp(word, "off", MIN(strlen(word), 3)))
+                       return strdup("off");
+       default:
+               return NULL;
+       }
+       return NULL;
+}
+
+static char autoanswer_usage[] =
+"Usage: autoanswer [on|off]\n"
+"       Enables or disables autoanswer feature.  If used without\n"
+"       argument, displays the current on/off status of autoanswer.\n"
+"       The default value of autoanswer is in 'alsa.conf'.\n";
+
+static int console_answer(int fd, int argc, char *argv[])
+{
+       if (argc != 1)
+               return RESULT_SHOWUSAGE;
+       if (!alsa.owner) {
+               ast_cli(fd, "No one is calling us\n");
+               return RESULT_FAILURE;
+       }
+       hookstate = 1;
+       cursound = -1;
+       needanswer++;
+       answer_sound();
+       return RESULT_SUCCESS;
+}
+
+static char sendtext_usage[] =
+"Usage: send text <message>\n"
+"       Sends a text message for display on the remote terminal.\n";
+
+static int console_sendtext(int fd, int argc, char *argv[])
+{
+       int tmparg = 1;
+       if (argc < 1)
+               return RESULT_SHOWUSAGE;
+       if (!alsa.owner) {
+               ast_cli(fd, "No one is calling us\n");
+               return RESULT_FAILURE;
+       }
+       if (strlen(text2send))
+               ast_cli(fd, "Warning: message already waiting to be sent, overwriting\n");
+       strcpy(text2send, "");
+       while(tmparg <= argc) {
+               strncat(text2send, argv[tmparg++], sizeof(text2send) - strlen(text2send));
+               strncat(text2send, " ", sizeof(text2send) - strlen(text2send));
+       }
+       needanswer++;
+       return RESULT_SUCCESS;
+}
+
+static char answer_usage[] =
+"Usage: answer\n"
+"       Answers an incoming call on the console (ALSA) channel.\n";
+
+static int console_hangup(int fd, int argc, char *argv[])
+{
+       if (argc != 1)
+               return RESULT_SHOWUSAGE;
+       cursound = -1;
+       if (!alsa.owner && !hookstate) {
+               ast_cli(fd, "No call to hangup up\n");
+               return RESULT_FAILURE;
+       }
+       hookstate = 0;
+       if (alsa.owner)
+               needhangup++;
+       return RESULT_SUCCESS;
+}
+
+static char hangup_usage[] =
+"Usage: hangup\n"
+"       Hangs up any call currently placed on the console.\n";
+
+
+static int console_dial(int fd, int argc, char *argv[])
+{
+       char tmp[256], *tmp2;
+       char *mye, *myc;
+       int b = 0;
+       if ((argc != 1) && (argc != 2))
+               return RESULT_SHOWUSAGE;
+       if (alsa.owner) {
+               if (argc == 2) {
+                       strncat(digits, argv[1], sizeof(digits) - strlen(digits));
+                       /* Wake up the polling thread */
+                       write(cmd[1], &b, sizeof(b));
+               } else {
+                       ast_cli(fd, "You're already in a call.  You can use this only to dial digits until you hangup\n");
+                       return RESULT_FAILURE;
+               }
+               return RESULT_SUCCESS;
+       }
+       mye = exten;
+       myc = context;
+       if (argc == 2) {
+               strncpy(tmp, argv[1], sizeof(tmp)-1);
+               strtok(tmp, "@");
+               tmp2 = strtok(NULL, "@");
+               if (strlen(tmp))
+                       mye = tmp;
+               if (tmp2 && strlen(tmp2))
+                       myc = tmp2;
+       }
+       if (ast_exists_extension(NULL, myc, mye, 1, NULL)) {
+               strncpy(alsa.exten, mye, sizeof(alsa.exten)-1);
+               strncpy(alsa.context, myc, sizeof(alsa.context)-1);
+               hookstate = 1;
+               alsa_new(&alsa, AST_STATE_UP);
+       } else
+               ast_cli(fd, "No such extension '%s' in context '%s'\n", mye, myc);
+       return RESULT_SUCCESS;
+}
+
+static char dial_usage[] =
+"Usage: dial [extension[@context]]\n"
+"       Dials a given extensison (";
+
+
+static struct ast_cli_entry myclis[] = {
+       { { "answer", NULL }, console_answer, "Answer an incoming console call", answer_usage },
+       { { "hangup", NULL }, console_hangup, "Hangup a call on the console", hangup_usage },
+       { { "dial", NULL }, console_dial, "Dial an extension on the console", dial_usage },
+       { { "send text", NULL }, console_sendtext, "Send text to the remote device", sendtext_usage },
+       { { "autoanswer", NULL }, console_autoanswer, "Sets/displays autoanswer", autoanswer_usage, autoanswer_complete }
+};
+
+int load_module()
+{
+       int res;
+       int x;
+       int flags;
+       struct ast_config *cfg = ast_load(config);
+       struct ast_variable *v;
+       res = pipe(cmd);
+       res = pipe(sndcmd);
+       if (res) {
+               ast_log(LOG_ERROR, "Unable to create pipe\n");
+               return -1;
+       }
+       flags = fcntl(cmd[0], F_GETFL);
+       fcntl(cmd[0], F_SETFL, flags | O_NONBLOCK);
+       flags = fcntl(cmd[1], F_GETFL);
+       fcntl(cmd[1], F_SETFL, flags | O_NONBLOCK);
+       res = soundcard_init();
+       if (res < 0) {
+               close(cmd[1]);
+               close(cmd[0]);
+               if (option_verbose > 1) {
+                       ast_verbose(VERBOSE_PREFIX_2 "No sound card detected -- console channel will be unavailable\n");
+                       ast_verbose(VERBOSE_PREFIX_2 "Turn off ALSA support by adding 'noload=chan_alsa.so' in /etc/asterisk/modules.conf\n");
+               }
+               return 0;
+       }
+#if 0
+       if (!full_duplex)
+               ast_log(LOG_WARNING, "XXX I don't work right with non-full duplex sound cards XXX\n");
+#endif
+       res = ast_channel_register(type, tdesc, AST_FORMAT_SLINEAR, alsa_request);
+       if (res < 0) {
+               ast_log(LOG_ERROR, "Unable to register channel class '%s'\n", type);
+               return -1;
+       }
+       for (x=0;x<sizeof(myclis)/sizeof(struct ast_cli_entry); x++)
+               ast_cli_register(myclis + x);
+       if (cfg) {
+               v = ast_variable_browse(cfg, "general");
+               while(v) {
+                       if (!strcasecmp(v->name, "autoanswer"))
+                               autoanswer = ast_true(v->value);
+                       else if (!strcasecmp(v->name, "silencesuppression"))
+                               silencesuppression = ast_true(v->value);
+                       else if (!strcasecmp(v->name, "silencethreshold"))
+                               silencethreshold = atoi(v->value);
+                       else if (!strcasecmp(v->name, "context"))
+                               strncpy(context, v->value, sizeof(context)-1);
+                       else if (!strcasecmp(v->name, "language"))
+                               strncpy(language, v->value, sizeof(language)-1);
+                       else if (!strcasecmp(v->name, "extension"))
+                               strncpy(exten, v->value, sizeof(exten)-1);
+                       else if (!strcasecmp(v->name, "input_device"))
+                               strncpy(indevname, v->value, sizeof(indevname)-1);
+                       else if (!strcasecmp(v->name, "output_device"))
+                               strncpy(outdevname, v->value, sizeof(outdevname)-1);
+                       v=v->next;
+               }
+               ast_destroy(cfg);
+       }
+       pthread_create(&sthread, NULL, sound_thread, NULL);
+#ifdef ALSA_MONITOR
+       if (alsa_monitor_start()) {
+               ast_log(LOG_ERROR, "Problem starting Monitoring\n");
+       }
+#endif  
+       return 0;
+}
+
+
+
+int unload_module()
+{
+       int x;
+       for (x=0;x<sizeof(myclis)/sizeof(struct ast_cli_entry); x++)
+               ast_cli_unregister(myclis + x);
+       close(readdev);
+       close(writedev);
+       if (cmd[0] > 0) {
+               close(cmd[0]);
+               close(cmd[1]);
+       }
+       if (sndcmd[0] > 0) {
+               close(sndcmd[0]);
+               close(sndcmd[1]);
+       }
+       if (alsa.owner)
+               ast_softhangup(alsa.owner);
+       if (alsa.owner)
+               return -1;
+       return 0;
+}
+
+char *description()
+{
+       return desc;
+}
+
+int usecount()
+{
+       int res;
+       ast_pthread_mutex_lock(&usecnt_lock);
+       res = usecnt;
+       ast_pthread_mutex_unlock(&usecnt_lock);
+       return res;
+}
+
+char *key()
+{
+       return ASTERISK_GPL_KEY;
+}