Several changes to codec_dahdi to play nice with G723.

This commit brings in the changes that were living out on the
svn/asterisk/team/sruffell/asterisk-1.4-transcoder branch.  codec_dahdi.c now
always uses signed linear as the simple codec so that a soft g729 codec will
not end up being preferred to the hardware codec.  There are also changes to
allow codec_dahdi.c to feed packets to the hardware in the native sample size of
the codec.  This solves problems with choppy audio when using G723. 


git-svn-id: http://svn.digium.com/svn/asterisk/branches/1.4@176810 f38db490-d61c-443f-a65b-d21fe96a405b

1 files changed, 314 insertions, 78 deletions

diff --git a/codecs/codec_dahdi.c b/codecs/codec_dahdi.c
index 347fc8012..ceffa3024 100644
--- a/codecs/codec_dahdi.c
+++ b/codecs/codec_dahdi.c
@@ -44,6 +44,7 @@ ASTERISK_FILE_VERSION(__FILE__, "$Revision$")
 #include <sys/ioctl.h>
 #include <errno.h>
 #include <sys/mman.h>
+#include <sys/poll.h>
 
 #include "asterisk/lock.h"
 #include "asterisk/translate.h"
@@ -56,8 +57,13 @@ ASTERISK_FILE_VERSION(__FILE__, "$Revision$")
 #include "asterisk/utils.h"
 #include "asterisk/linkedlists.h"
 #include "asterisk/dahdi_compat.h"
+#include "asterisk/frame.h"
+#include "asterisk/ulaw.h"
 
-#define BUFFER_SAMPLES	8000
+#define BUFFER_SIZE 8000
+
+#define G723_SAMPLES 240
+#define G729_SAMPLES 160
 
 static unsigned int global_useplc = 0;
 
@@ -105,13 +111,53 @@ struct translator {
 
 static AST_LIST_HEAD_STATIC(translators, translator);
 
-struct pvt {
+struct codec_dahdi_pvt {
 	int fd;
-	int fake;
-	int samples;
 	struct dahdi_transcoder_formats fmts;
+	unsigned int softslin:1;
+	unsigned int fake:2;
+	uint16_t required_samples;
+	uint16_t samples_in_buffer;
+	uint8_t ulaw_buffer[1024];
 };
 
+/* Only used by a decoder */
+static int ulawtolin(struct ast_trans_pvt *pvt)
+{
+	struct codec_dahdi_pvt *ztp = pvt->pvt;
+	int i = ztp->required_samples;
+	uint8_t *src = &ztp->ulaw_buffer[0];
+	int16_t *dst = (int16_t *)pvt->outbuf + pvt->datalen;
+
+	/* convert and copy in outbuf */
+	while (i--) {
+		*dst++ = AST_MULAW(*src++);
+	}
+
+	return 0;
+}
+
+/* Only used by an encoder. */
+static int lintoulaw(struct ast_trans_pvt *pvt, struct ast_frame *f)
+{
+	struct codec_dahdi_pvt *ztp = pvt->pvt;
+	int i = f->samples;
+	uint8_t *dst = &ztp->ulaw_buffer[ztp->samples_in_buffer];
+	int16_t *src = (int16_t*)f->data;
+
+	if (ztp->samples_in_buffer + i > sizeof(ztp->ulaw_buffer)) {
+		ast_log(LOG_ERROR, "Out of buffer space!\n");
+		return -i;
+	}
+
+	while (i--) {
+		*dst++ = AST_LIN2MU(*src++);
+	}
+
+	ztp->samples_in_buffer += f->samples;
+	return 0;
+}
+
 static int transcoder_show(int fd, int argc, char **argv)
 {
 	struct channel_usage copy;
@@ -126,68 +172,79 @@ static int transcoder_show(int fd, int argc, char **argv)
 	return RESULT_SUCCESS;
 }
 
-static int zap_framein(struct ast_trans_pvt *pvt, struct ast_frame *f)
+static void dahdi_write_frame(struct codec_dahdi_pvt *ztp, const uint8_t *buffer, const ssize_t count)
 {
 	int res;
-	struct pvt *ztp = pvt->pvt;
-
-	if (f->subclass) {
-		/* Give the frame to the hardware transcoder... */
-		res = write(ztp->fd, f->data, f->datalen); 
+	struct pollfd p = {0};
+	if (!count) return;
+	res = write(ztp->fd, buffer, count); 
+	if (option_verbose > 10) {
 		if (-1 == res) {
 			ast_log(LOG_ERROR, "Failed to write to transcoder: %s\n", strerror(errno));
+		} 
+		if (count != res) {
+			ast_log(LOG_ERROR, "Requested write of %zd bytes, but only wrote %d bytes.\n", count, res);
 		}
-		if (f->datalen != res) {
-			ast_log(LOG_ERROR, "Requested write of %d bytes, but only wrote %d bytes.\n", f->datalen, res);
-		}
-		res = -1;
-		pvt->samples += f->samples;
-	} else {
-		/* Fake a return frame for calculation purposes */
-		ztp->fake = 2;
-		pvt->samples = f->samples;
-		res = 0;
 	}
-	return res;
+	p.fd = ztp->fd;
+	p.events = POLLOUT;
+	res = poll(&p, 1, 50);
 }
 
-static struct ast_frame *zap_frameout(struct ast_trans_pvt *pvt)
+static int dahdi_encoder_framein(struct ast_trans_pvt *pvt, struct ast_frame *f)
 {
-	struct pvt *ztp = pvt->pvt;
+	struct codec_dahdi_pvt *ztp = pvt->pvt;
 
-	if (0 == ztp->fake) {
-		int res;
-		/* Let's check to see if there is a new frame for us.... */
-		res = read(ztp->fd, pvt->outbuf + pvt->datalen, pvt->t->buf_size - pvt->datalen);
-		if (-1 == res) {
-			if (EWOULDBLOCK == errno) {
-				/* Nothing waiting... */
-				return NULL;
-			} else {
-				ast_log(LOG_ERROR, "Failed to read from transcoder: %s\n", strerror(errno));
-				return NULL;
-			}
-		} else {
-			pvt->f.samples = ztp->samples;
-			pvt->f.datalen = res;
-			pvt->datalen = 0;
-			pvt->f.frametype = AST_FRAME_VOICE;
-			pvt->f.subclass = 1 <<  (pvt->t->dstfmt);
-			pvt->f.mallocd = 0;
-			pvt->f.offset = AST_FRIENDLY_OFFSET;
-			pvt->f.src = pvt->t->name;
-			pvt->f.data = pvt->outbuf;
-			ast_set_flag(&pvt->f, AST_FRFLAG_FROM_TRANSLATOR);
-
-			return &pvt->f;
+	if (!f->subclass) {
+		/* We're just faking a return for calculation purposes. */
+		ztp->fake = 2;
+		pvt->samples = f->samples;
+		return 0;
+	}
+
+	/* Buffer up the packets and send them to the hardware if we
+	 * have enough samples set up. */
+	if (ztp->softslin) {
+		if (lintoulaw(pvt, f)) {
+			 return -1;
+		}
+	} else {
+		/* NOTE:  If softslin support is not needed, and the sample
+		 * size is equal to the required sample size, we wouldn't
+		 * need this copy operation.  But at the time this was
+		 * written, only softslin is supported. */
+		if (ztp->samples_in_buffer + f->samples > sizeof(ztp->ulaw_buffer)) {
+			ast_log(LOG_ERROR, "Out of buffer space.\n");
+			return -1;
 		}
+		memcpy(&ztp->ulaw_buffer[ztp->samples_in_buffer], f->data, f->samples);
+		ztp->samples_in_buffer += f->samples;
+	}
 
-	} else if (2 == ztp->fake) {
+	while (ztp->samples_in_buffer > ztp->required_samples) {
+		dahdi_write_frame(ztp, ztp->ulaw_buffer, ztp->required_samples);
+		ztp->samples_in_buffer -= ztp->required_samples;
+		if (ztp->samples_in_buffer) {
+			/* Shift any remaining bytes down. */
+			memmove(ztp->ulaw_buffer, &ztp->ulaw_buffer[ztp->required_samples],
+				ztp->samples_in_buffer);
+		}
+	}
+	pvt->samples += f->samples;
+	pvt->datalen = 0;
+	return -1;
+}
 
+static struct ast_frame *dahdi_encoder_frameout(struct ast_trans_pvt *pvt)
+{
+	struct codec_dahdi_pvt *ztp = pvt->pvt;
+	int res;
+
+	if (2 == ztp->fake) {
 		ztp->fake = 1;
 		pvt->f.frametype = AST_FRAME_VOICE;
 		pvt->f.subclass = 0;
-		pvt->f.samples = 160;
+		pvt->f.samples = ztp->required_samples;
 		pvt->f.data = NULL;
 		pvt->f.offset = 0;
 		pvt->f.datalen = 0;
@@ -198,17 +255,128 @@ static struct ast_frame *zap_frameout(struct ast_trans_pvt *pvt)
 		return &pvt->f;
 
 	} else if (1 == ztp->fake) {
+		ztp->fake = 0;
+		return NULL;
+	}
+
+	res = read(ztp->fd, pvt->outbuf + pvt->datalen, pvt->t->buf_size - pvt->datalen);
+	if (-1 == res) {
+		if (EWOULDBLOCK == errno) {
+			/* Nothing waiting... */
+			return NULL;
+		} else {
+			ast_log(LOG_ERROR, "Failed to read from transcoder: %s\n", strerror(errno));
+			return NULL;
+		}
+	} else {
+		pvt->f.datalen = res;
+		pvt->f.samples = ztp->required_samples;
+		pvt->f.frametype = AST_FRAME_VOICE;
+		pvt->f.subclass = 1 <<  (pvt->t->dstfmt);
+		pvt->f.mallocd = 0;
+		pvt->f.offset = AST_FRIENDLY_OFFSET;
+		pvt->f.src = pvt->t->name;
+		pvt->f.data = pvt->outbuf;
+		ast_set_flag(&pvt->f, AST_FRFLAG_FROM_TRANSLATOR);
+
+		pvt->samples = 0;
+		pvt->datalen = 0;
+		return &pvt->f;
+	}
+
+	/* Shouldn't get here... */
+	return NULL;
+}
+
+static int dahdi_decoder_framein(struct ast_trans_pvt *pvt, struct ast_frame *f)
+{
+	struct codec_dahdi_pvt *ztp = pvt->pvt;
+
+	if (!f->subclass) {
+		/* We're just faking a return for calculation purposes. */
+		ztp->fake = 2;
+		pvt->samples = f->samples;
+		return 0;
+	}
+
+	if (!f->datalen) {
+		if (f->samples != ztp->required_samples) {
+			ast_log(LOG_ERROR, "%d != %d %d\n", f->samples, ztp->required_samples, f->datalen);
+		}
+	}
+	dahdi_write_frame(ztp, f->data, f->datalen);
+	pvt->samples += f->samples;
+	pvt->datalen = 0;
+	return -1;
+}
+
+static struct ast_frame *dahdi_decoder_frameout(struct ast_trans_pvt *pvt)
+{
+	int res;
+	struct codec_dahdi_pvt *ztp = pvt->pvt;
 
+	if (2 == ztp->fake) {
+		ztp->fake = 1;
+		pvt->f.frametype = AST_FRAME_VOICE;
+		pvt->f.subclass = 0;
+		pvt->f.samples = ztp->required_samples;
+		pvt->f.data = NULL;
+		pvt->f.offset = 0;
+		pvt->f.datalen = 0;
+		pvt->f.mallocd = 0;
+		ast_set_flag(&pvt->f, AST_FRFLAG_FROM_TRANSLATOR);
+		pvt->samples = 0;
+		return &pvt->f;
+	} else if (1 == ztp->fake) {
+		pvt->samples = 0;
+		ztp->fake = 0;
 		return NULL;
+	}
+
+	/* Let's check to see if there is a new frame for us.... */
+	if (ztp->softslin) {
+		res = read(ztp->fd, ztp->ulaw_buffer, sizeof(ztp->ulaw_buffer));
+	} else {
+		res = read(ztp->fd, pvt->outbuf + pvt->datalen, pvt->t->buf_size - pvt->datalen);
+	}
+
+	if (-1 == res) {
+		if (EWOULDBLOCK == errno) {
+			/* Nothing waiting... */
+			return NULL;
+		} else {
+			ast_log(LOG_ERROR, "Failed to read from transcoder: %s\n", strerror(errno));
+			return NULL;
+		}
+	} else {
+		if (ztp->softslin) {
+			ulawtolin(pvt);
+			pvt->f.datalen = res * 2;
+		} else {
+			pvt->f.datalen = res;
+		}
+		pvt->datalen = 0;
+		pvt->f.frametype = AST_FRAME_VOICE;
+		pvt->f.subclass = 1 <<  (pvt->t->dstfmt);
+		pvt->f.mallocd = 0;
+		pvt->f.offset = AST_FRIENDLY_OFFSET;
+		pvt->f.src = pvt->t->name;
+		pvt->f.data = pvt->outbuf;
+		pvt->f.samples = ztp->required_samples;
+		ast_set_flag(&pvt->f, AST_FRFLAG_FROM_TRANSLATOR);
+		pvt->samples = 0;
 
+		return &pvt->f;
 	}
+
 	/* Shouldn't get here... */
 	return NULL;
 }
 
-static void zap_destroy(struct ast_trans_pvt *pvt)
+
+static void dahdi_destroy(struct ast_trans_pvt *pvt)
 {
-	struct pvt *ztp = pvt->pvt;
+	struct codec_dahdi_pvt *ztp = pvt->pvt;
 
 	switch (ztp->fmts.dstfmt) {
 	case AST_FORMAT_G729A:
@@ -223,29 +391,57 @@ static void zap_destroy(struct ast_trans_pvt *pvt)
 	close(ztp->fd);
 }
 
-static int zap_translate(struct ast_trans_pvt *pvt, int dest, int source)
+static int dahdi_translate(struct ast_trans_pvt *pvt, int dest, int source)
 {
 	/* Request translation through zap if possible */
 	int fd;
-	struct pvt *ztp = pvt->pvt;
+	struct codec_dahdi_pvt *ztp = pvt->pvt;
 	int flags;
+	int tried_once = 0;
+#ifdef HAVE_ZAPTEL
+	const char *dev_filename = "/dev/zap/transcode";
+#else
+	const char *dev_filename = "/dev/dahdi/transcode";
+#endif
 	
-	if ((fd = open(DAHDI_FILE_TRANSCODE, O_RDWR)) < 0) {
-		ast_log(LOG_ERROR, "Failed to open " DAHDI_FILE_TRANSCODE ": %s\n", strerror(errno));
+	if ((fd = open(dev_filename, O_RDWR)) < 0) {
+		ast_log(LOG_ERROR, "Failed to open %s: %s\n", dev_filename, strerror(errno));
 		return -1;
 	}
 	
 	ztp->fmts.srcfmt = (1 << source);
 	ztp->fmts.dstfmt = (1 << dest);
 
-	ast_log(LOG_VERBOSE, "Opening transcoder channel from %d to %d.\n", source, dest);
+	ast_log(LOG_DEBUG, "Opening transcoder channel from %d to %d.\n", source, dest);
 
+retry:
 	if (ioctl(fd, DAHDI_TC_ALLOCATE, &ztp->fmts)) {
+		if ((ENODEV == errno) && !tried_once) {
+			/* We requested to translate to/from an unsupported
+			 * format.  Most likely this is because signed linear
+			 * was not supported by any hardware devices even
+			 * though this module always registers signed linear
+			 * support. In this case we'll retry, requesting
+			 * support for ULAW instead of signed linear and then
+			 * we'll just convert from ulaw to signed linear in
+			 * software. */
+			if (AST_FORMAT_SLINEAR == ztp->fmts.srcfmt) {
+				ast_log(LOG_DEBUG, "Using soft_slin support on source\n");
+				ztp->softslin = 1;
+				ztp->fmts.srcfmt = AST_FORMAT_ULAW;
+			} else if (AST_FORMAT_SLINEAR == ztp->fmts.dstfmt) {
+				ast_log(LOG_DEBUG, "Using soft_slin support on destination\n");
+				ztp->softslin = 1;
+				ztp->fmts.dstfmt = AST_FORMAT_ULAW;
+			}
+			tried_once = 1;
+			goto retry;
+		}
 		ast_log(LOG_ERROR, "Unable to attach to transcoder: %s\n", strerror(errno));
 		close(fd);
 
 		return -1;
-	}
+	} 
 
 	flags = fcntl(fd, F_GETFL);
 	if (flags > - 1) {
@@ -255,17 +451,7 @@ static int zap_translate(struct ast_trans_pvt *pvt, int dest, int source)
 
 	ztp->fd = fd;
 
-	switch (ztp->fmts.dstfmt) {
-	case AST_FORMAT_G729A:
-		ztp->samples = 160;
-		break;
-	case AST_FORMAT_G723_1:
-		ztp->samples = 240;
-		break;
-	default:
-		ztp->samples = 160;
-		break;
-	};
+	ztp->required_samples = ((ztp->fmts.dstfmt|ztp->fmts.srcfmt)&AST_FORMAT_G723_1) ? G723_SAMPLES : G729_SAMPLES;
 
 	switch (ztp->fmts.dstfmt) {
 	case AST_FORMAT_G729A:
@@ -282,9 +468,9 @@ static int zap_translate(struct ast_trans_pvt *pvt, int dest, int source)
 	return 0;
 }
 
-static int zap_new(struct ast_trans_pvt *pvt)
+static int dahdi_new(struct ast_trans_pvt *pvt)
 {
-	return zap_translate(pvt, pvt->t->dstfmt, pvt->t->srcfmt);
+	return dahdi_translate(pvt, pvt->t->dstfmt, pvt->t->srcfmt);
 }
 
 static struct ast_frame *fakesrc_sample(void)
@@ -299,26 +485,58 @@ static struct ast_frame *fakesrc_sample(void)
 	return &f;
 }
 
+static int is_encoder(struct translator *zt)
+{
+	if (zt->t.srcfmt&(AST_FORMAT_ULAW|AST_FORMAT_ALAW|AST_FORMAT_SLINEAR)) {
+		return 1;
+	} else {
+		return 0;
+	}
+}
+
 static int register_translator(int dst, int src)
 {
 	struct translator *zt;
 	int res;
 
-	if (!(zt = ast_calloc(1, sizeof(*zt))))
+	if (!(zt = ast_calloc(1, sizeof(*zt)))) {
 		return -1;
+	}
 
 	snprintf((char *) (zt->t.name), sizeof(zt->t.name), "zap%sto%s", 
 		 ast_getformatname((1 << src)), ast_getformatname((1 << dst)));
 	zt->t.srcfmt = (1 << src);
 	zt->t.dstfmt = (1 << dst);
-	zt->t.newpvt = zap_new;
-	zt->t.framein = zap_framein;
-	zt->t.frameout = zap_frameout;
-	zt->t.destroy = zap_destroy;
+	zt->t.buf_size = BUFFER_SIZE;
+	if (is_encoder(zt)) {
+		zt->t.framein = dahdi_encoder_framein;
+		zt->t.frameout = dahdi_encoder_frameout;
+#if 0
+		zt->t.buffer_samples = 0;
+#endif
+	} else {
+		zt->t.framein = dahdi_decoder_framein;
+		zt->t.frameout = dahdi_decoder_frameout;
+#if 0
+		if (AST_FORMAT_G723_1 == zt->t.srcfmt) {
+			zt->t.plc_samples = G723_SAMPLES;
+		} else {
+			zt->t.plc_samples = G729_SAMPLES;
+		}
+		zt->t.buffer_samples = zt->t.plc_samples * 8;
+#endif
+	}
+	zt->t.destroy = dahdi_destroy;
+	zt->t.buffer_samples = 0;
+	zt->t.newpvt = dahdi_new;
 	zt->t.sample = fakesrc_sample;
+#if 0
 	zt->t.useplc = global_useplc;
-	zt->t.buf_size = BUFFER_SAMPLES * 2;
-	zt->t.desc_size = sizeof(struct pvt);
+#endif
+	zt->t.useplc = 0;
+	zt->t.native_plc = 0;
+
+	zt->t.desc_size = sizeof(struct codec_dahdi_pvt);
 	if ((res = ast_register_translator(&zt->t))) {
 		free(zt);
 		return -1;
@@ -423,8 +641,25 @@ static int find_transcoders(void)
 	for (info.tcnum = 0; !(res = ioctl(fd, DAHDI_TC_GETINFO, &info)); info.tcnum++) {
 		if (option_verbose > 1)
 			ast_verbose(VERBOSE_PREFIX_2 "Found transcoder '%s'.\n", info.name);
+
+		/* Complex codecs need to support signed linear.  If the
+		 * hardware transcoder does not natively support signed linear
+		 * format, we will emulate it in software directly in this
+		 * module. Also, do not allow direct ulaw/alaw to complex
+		 * codec translation, since that will prevent the generic PLC
+		 * functions from working. */
+		if (info.dstfmts & (AST_FORMAT_ULAW | AST_FORMAT_ALAW)) {
+			info.dstfmts |= AST_FORMAT_SLINEAR;
+			info.dstfmts &= ~(AST_FORMAT_ULAW | AST_FORMAT_ALAW);
+		}
+		if (info.srcfmts & (AST_FORMAT_ULAW | AST_FORMAT_ALAW)) {
+			info.srcfmts |= AST_FORMAT_SLINEAR;
+			info.srcfmts &= ~(AST_FORMAT_ULAW | AST_FORMAT_ALAW);
+		}
+
 		build_translators(&map, info.dstfmts, info.srcfmts);
 		ast_atomic_fetchadd_int(&channels.total, info.numchannels / 2);
+
 	}
 
 	close(fd);
@@ -466,6 +701,7 @@ static int unload_module(void)
 
 static int load_module(void)
 {
+	ast_ulaw_init();
 	parse_config();
 	find_transcoders();
 	ast_cli_register_multiple(cli, sizeof(cli) / sizeof(cli[0]));