Revision
17110
Author
moy
Date
2010-03-26 10:14:44 -0500 (Fri, 26 Mar 2010)

Log Message

added mod_sangoma_codec

Added Paths

Diff

Added: freeswitch/trunk/src/mod/codecs/mod_sangoma_codec/Makefile (0 => 17110)


--- freeswitch/trunk/src/mod/codecs/mod_sangoma_codec/Makefile	                        (rev 0)
+++ freeswitch/trunk/src/mod/codecs/mod_sangoma_codec/Makefile	2010-03-26 15:14:44 UTC (rev 17110)
@@ -0,0 +1,3 @@
+BASE=../../../..
+LOCAL_LDFLAGS += -lsangoma_transcode
+include $(BASE)/build/modmake.rules

Added: freeswitch/trunk/src/mod/codecs/mod_sangoma_codec/mod_sangoma_codec.c (0 => 17110)


--- freeswitch/trunk/src/mod/codecs/mod_sangoma_codec/mod_sangoma_codec.c	                        (rev 0)
+++ freeswitch/trunk/src/mod/codecs/mod_sangoma_codec/mod_sangoma_codec.c	2010-03-26 15:14:44 UTC (rev 17110)
@@ -0,0 +1,978 @@
+/*
+ * Copyright (c) 2010, Sangoma Technologies
+ * Moises Silva <moy@sangoma.com>
+ * All rights reserved.
+ * 
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 
+ * * Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * 
+ * * Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution.
+ * 
+ * * Neither the name of the original author; nor the names of any contributors
+ * may be used to endorse or promote products derived from this software
+ * without specific prior written permission.
+ * 
+ * 
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE COPYRIGHT OWNER
+ * OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
+ * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
+ * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
+ * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
+ * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+ * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include <switch.h>
+#include <g711.h>
+
+#include <sangoma_transcode.h>
+
+#ifdef __linux__
+/* for ethernet device query */
+#include <sys/ioctl.h>
+#include <net/if.h>
+#include <arpa/inet.h>
+#include <errno.h>
+#endif
+
+SWITCH_MODULE_LOAD_FUNCTION(mod_sangoma_codec_load);
+SWITCH_MODULE_SHUTDOWN_FUNCTION(mod_sangoma_codec_shutdown);
+SWITCH_MODULE_DEFINITION(mod_sangoma_codec, mod_sangoma_codec_load, mod_sangoma_codec_shutdown, NULL);
+
+#define IANA_ULAW 0
+#define SANGOMA_SESS_HASH_KEY_FORMAT "sngtc%lu"
+
+/* it seemed we need higher PTIME than the calling parties, so we assume nobody will use higher ptime than 40 */
+#define SANGOMA_DEFAULT_SAMPLING_RATE 80
+#define SANGOMA_TRANSCODE_CONFIG "sangoma_codec.conf" 
+
+#define SANGOMA_DEFAULT_UDP_PORT 15000
+#define SANGOMA_MIN_UDP_PORT 0
+#define SANGOMA_MAX_UDP_PORT 65535
+
+/* \brief vocallos configuration */
+static sngtc_init_cfg_t g_init_cfg;
+
+/* \brief protect vocallo session creation and destroy */
+static switch_mutex_t *g_sessions_lock = NULL;
+
+/* \brief next unique session id (protected by g_sessions_lock) */
+unsigned long long g_next_session_id = 0;
+
+/* hash of sessions (I think a linked list suits better here, but FS does not have the data type) */
+switch_hash_t *g_sessions_hash = NULL;
+
+typedef struct vocallo_codec_s {
+	int codec_id; /* vocallo codec ID */
+	int iana; /* IANA code to register in FS */
+	const char *iana_name; /* IANA name to register in FS */
+	const char *fs_name;
+	int maxms; /* max supported ms */
+	int bps; /* bits per second */
+
+	/* following values must be set assuming frames of 10ms */
+	int mpf; /* microseconds per frame */
+	int spf; /* samples per frame */
+	int bpfd; /* bytes per frame decompressed */
+	int bpfc; /* bytes per frame compressed */
+} vocallo_codec_t;
+
+vocallo_codec_t g_codec_map[] =
+{
+	{ SNGTC_CODEC_PCMU,    0,   "PCMU",    "Sangoma PCMU",      40, 64000,  10000, 80,  160, 80  },
+	{ SNGTC_CODEC_PCMA,    8,   "PCMA",    "Sangoma PCMA",      40, 64000,  10000, 80,  160, 80  },
+	{ SNGTC_CODEC_L16_1,   10,  "L16",     "Sangoma L16",       40, 120000, 10000, 80,  160, 160 },
+	{ SNGTC_CODEC_G729AB,  18,  "G729",    "Sangoma G729",      40, 8000,   10000, 80,  160, 10  },
+	{ SNGTC_CODEC_G722,    9,   "G722",    "Sangoma G722",      20, 64000,  10000, 80,  320, 80  },
+	{ SNGTC_CODEC_G726_32, 122, "G726-32", "Sangoma G.726 32k", 40, 32000,  10000, 80,  160, 20  },
+#if 0
+	FIXME: see mod_ilbc, and mod_voipcodecs to do this right
+	{ SNGTC_CODEC_GSM_FR,  3,   "GSM",     "Sangoma GSM",       20, 13200,  20000, 160, 320, 33  },
+	{ SNGTC_CODEC_ILBC,    97, "ILBC", "Sangoma ILBC", 40, mpf, spf, bpfd, bpfc },
+#endif
+	{ -1,                  -1,  NULL,      NULL,                -1, -1,     -1,    -1,  -1,  -1  },
+};
+
+struct codec_data {
+	/* sngtc request and reply */
+	sngtc_codec_request_t request;
+	sngtc_codec_reply_t reply;
+
+	/* rtp streams */
+	void *txrtp;
+	void *rxrtp;
+
+	/* packet counters */
+	unsigned long tx;
+	unsigned long rx;
+
+	/* Lost packets */
+  	long lastrxseqno;
+	unsigned long rxlost;
+
+	/* avg Rx time */
+	switch_time_t avgrxus;
+	switch_time_t last_rx_time;
+
+};
+
+struct sangoma_transcoding_session {
+	/* unique session id */
+	unsigned long sessid;
+	char hashkey[25];
+
+	/* encoder and decoder */
+	struct codec_data encoder;
+	struct codec_data decoder;
+
+	/* codec implementation */
+	const switch_codec_implementation_t *impl;
+
+	/* memory pool */
+	switch_memory_pool_t *pool;
+};
+
+static int codec_id_to_iana(int codec_id)
+{
+	int i;
+	for (i = 0; g_codec_map[i].codec_id != -1; i++) {
+		if (codec_id == g_codec_map[i].codec_id) {
+			return g_codec_map[i].iana;
+		}
+	}
+	return -1;
+}
+
+static vocallo_codec_t *get_codec_from_iana(int iana)
+{
+	int i;
+	for (i = 0; g_codec_map[i].codec_id != -1; i++) {
+		if (iana == g_codec_map[i].iana) {
+			return &g_codec_map[i];
+		}
+	}
+	return NULL;
+}
+
+static int sangoma_create_rtp(void *usr_priv, sngtc_codec_request_leg_t *codec_reg_leg, sngtc_codec_reply_leg_t* codec_reply_leg, void **rtp_fd)
+{
+	switch_rtp_t *rtp_session = NULL;
+	switch_port_t rtp_port;
+	char codec_ip[255];
+	char local_ip[255];
+	switch_rtp_flag_t flags = 0;
+	int iana = 0;
+	const char *err = NULL;
+	struct sangoma_transcoding_session *sess = usr_priv;
+	struct in_addr local_ip_addr = { 0 };
+
+	local_ip_addr.s_addr = htonl(codec_reply_leg->host_ip);
+	
+	switch_inet_ntop(AF_INET, &local_ip_addr, local_ip, sizeof(local_ip));
+
+	/* request a port */
+	if (!(rtp_port = switch_rtp_request_port(local_ip))) {
+		switch_log_printf(SWITCH_CHANNEL_LOG, SWITCH_LOG_ERROR, "Failed to allocate RTP port for IP %s\n", local_ip);
+		return -1;
+	}
+	switch_log_printf(SWITCH_CHANNEL_LOG, SWITCH_LOG_DEBUG, "Allocated port %d for IP %s\n", rtp_port, local_ip);
+
+	codec_reg_leg->host_udp_port = rtp_port;
+
+	sngtc_codec_ipv4_hex_to_str(codec_reply_leg->codec_ip, codec_ip);
+
+	iana = codec_id_to_iana(codec_reg_leg->codec_id);
+	switch_log_printf(SWITCH_CHANNEL_LOG, SWITCH_LOG_INFO, "Creating RTP session for host (%s/%d)  vocallo(%s/%d) Iana=%d sample=%d ms=%d idx=%lu\n",
+					  local_ip, rtp_port, codec_ip, codec_reply_leg->codec_udp_port, iana, 
+					  codec_reg_leg->sample_rate, codec_reg_leg->ms*1000, sess->sessid);
+
+	/* create the RTP socket */
+	rtp_session = switch_rtp_new(local_ip, rtp_port, 
+			codec_ip, codec_reply_leg->codec_udp_port, 
+			iana,
+			codec_reg_leg->ms*8, /* samples per interval, FIXME: do based on sampling rate */
+			codec_reg_leg->ms*1000, /* ms per packet */
+			flags, NULL, &err, sess->pool);
+
+	if (!rtp_session) {
+		switch_log_printf(SWITCH_CHANNEL_LOG, SWITCH_LOG_ERROR, "failed to create switch rtp session: %s\n", err);
+		return -1;
+	}
+
+	*rtp_fd = rtp_session;
+
+	return 0;
+}
+
+static int sangoma_destroy_rtp(void *usr_priv, void *fd)
+{
+	switch_rtp_t *rtp = fd;
+	switch_rtp_destroy(&rtp);
+	return 0;
+}
+
+static switch_status_t switch_sangoma_init(switch_codec_t *codec, switch_codec_flag_t flags, const switch_codec_settings_t *codec_settings)
+{
+	uint32_t encoding, decoding;
+	struct sangoma_transcoding_session *sess = NULL;
+	vocallo_codec_t *vcodec;
+	
+	switch_log_printf(SWITCH_CHANNEL_LOG, SWITCH_LOG_DEBUG, "Sangoma init called.\n");
+
+	encoding = (flags & SWITCH_CODEC_FLAG_ENCODE);
+	decoding = (flags & SWITCH_CODEC_FLAG_DECODE);
+
+	if (!(encoding || decoding)) {
+		return SWITCH_STATUS_FALSE;
+	}
+
+	if (!(sess = switch_core_alloc(codec->memory_pool, sizeof(*sess)))) {
+		return SWITCH_STATUS_FALSE;
+	}
+	memset(sess, 0, sizeof(*sess));
+
+	sess->encoder.lastrxseqno = -1;
+	sess->decoder.lastrxseqno = -1;
+
+	sess->pool = codec->memory_pool;
+	sess->impl = codec->implementation;
+
+	vcodec = get_codec_from_iana(codec->implementation->ianacode);
+	
+	switch_mutex_lock(g_sessions_lock);
+
+	if (encoding) {
+		sess->encoder.request.usr_priv = sess;
+		sess->encoder.request.a.codec_id = SNGTC_CODEC_PCMU;
+		sess->encoder.request.a.ms = codec->implementation->microseconds_per_packet/1000;
+		sess->encoder.request.a.sample_rate = codec->implementation->actual_samples_per_second;
+
+		sess->encoder.request.b.codec_id = vcodec->codec_id;
+		sess->encoder.request.b.ms = codec->implementation->microseconds_per_packet/1000;
+		sess->encoder.request.b.sample_rate = codec->implementation->actual_samples_per_second;
+	}
+
+	if (decoding) {
+		sess->decoder.request.usr_priv = sess;
+		sess->decoder.request.a.codec_id = vcodec->codec_id;
+		sess->decoder.request.a.ms = codec->implementation->microseconds_per_packet/1000;
+		sess->decoder.request.a.sample_rate = codec->implementation->actual_samples_per_second;
+
+		sess->decoder.request.b.codec_id = SNGTC_CODEC_PCMU;
+		sess->decoder.request.b.ms = codec->implementation->microseconds_per_packet/1000;
+		sess->decoder.request.b.sample_rate = codec->implementation->actual_samples_per_second;
+
+	}
+
+	sess->sessid = g_next_session_id++;
+	switch_snprintf(sess->hashkey, sizeof(sess->hashkey), SANGOMA_SESS_HASH_KEY_FORMAT, sess->sessid);
+	switch_core_hash_insert(g_sessions_hash, sess->hashkey, sess);
+
+	switch_mutex_unlock(g_sessions_lock);
+
+	codec->private_info = sess;
+
+	return SWITCH_STATUS_SUCCESS;
+}
+
+static switch_status_t switch_sangoma_encode(switch_codec_t *codec, switch_codec_t *other_codec,	/* codec that was used by the other side */
+										  void *decoded_data,	/* decoded data that we must encode */
+										  uint32_t decoded_data_len /* decoded data length */ ,
+										  uint32_t decoded_rate /* rate of the decoded data */ ,
+										  void *encoded_data,	/* here we will store the encoded data */
+										  uint32_t *encoded_data_len,	/* here we will set the length of the encoded data */
+										  uint32_t *encoded_rate /* here we will set the rate of the encoded data */ ,
+										  unsigned int *flag /* frame flag, see switch_frame_flag_enum_t */ )
+{
+	/* FS core checks the actual samples per second and microseconds per packet to determine the buffer size in the worst case scenario, no need to check
+	 * whether the buffer passed in by the core (encoded_data) will be big enough */
+	switch_frame_t ulaw_frame;
+	switch_frame_t encoded_frame;
+	switch_status_t sres;
+	switch_time_t now_time, difftime;
+	unsigned char ebuf_ulaw[decoded_data_len / 2];
+	short *dbuf_linear;
+	int i = 0;
+	int res = 0;
+	struct sangoma_transcoding_session *sess = codec->private_info;
+
+	/* start assuming we will not encode anything */
+	*encoded_data_len = 0;
+
+	/* initialize on first use */
+	if (!sess->encoder.txrtp) {
+		int err = 0;
+		switch_mutex_lock(g_sessions_lock);
+		err = sngtc_create_transcoding_session(&sess->encoder.request, &sess->encoder.reply, 0);
+		if (err) {
+			switch_mutex_unlock(g_sessions_lock);
+			switch_log_printf(SWITCH_CHANNEL_LOG, SWITCH_LOG_ERROR, "Failed to create Sangoma encoding session.\n");
+			return SWITCH_STATUS_FALSE;
+		}
+		sess->encoder.txrtp = sess->encoder.reply.tx_fd;
+		sess->encoder.rxrtp = sess->encoder.reply.rx_fd;
+		switch_mutex_unlock(g_sessions_lock);
+	}
+
+	/* transcode to ulaw first */
+	dbuf_linear = decoded_data;
+
+	for (i = 0; i < decoded_data_len / sizeof(short); i++) {
+		ebuf_ulaw[i] = linear_to_ulaw(dbuf_linear[i]);
+	}
+	
+	/* do the writing */
+	memset(&ulaw_frame, 0, sizeof(ulaw_frame));	
+	ulaw_frame.source = __FUNCTION__;
+	ulaw_frame.data = ebuf_ulaw;
+	ulaw_frame.datalen = i;
+	ulaw_frame.payload = IANA_ULAW;
+
+	res = switch_rtp_write_frame(sess->encoder.txrtp, &ulaw_frame);
+	if (-1 == res) {
+		switch_log_printf(SWITCH_CHANNEL_LOG, SWITCH_LOG_ERROR, "Failed to write to Sangoma encoder RTP session.\n");
+		return SWITCH_STATUS_FALSE;
+	}
+
+	if (res < i) {
+		switch_log_printf(SWITCH_CHANNEL_LOG, SWITCH_LOG_ERROR, 
+				"Requested to write %d bytes to Sangoma encoder RTP session, but wrote %d bytes.\n", i, res);
+		return SWITCH_STATUS_FALSE;
+	}
+	sess->encoder.tx++;
+
+	/* do the reading */
+	memset(&encoded_frame, 0, sizeof(encoded_frame));
+	sres = switch_rtp_zerocopy_read_frame(sess->encoder.rxrtp, &encoded_frame, SWITCH_IO_FLAG_NOBLOCK);
+	if (sres == SWITCH_STATUS_GENERR) {
+		switch_log_printf(SWITCH_CHANNEL_LOG, SWITCH_LOG_ERROR, "Failed to read on Sangoma encoder RTP session: %d\n", sres);
+		return SWITCH_STATUS_FALSE;
+	}
+
+	if (0 == encoded_frame.datalen) {
+		switch_log_printf(SWITCH_CHANNEL_LOG, SWITCH_LOG_DEBUG, "No output on Sangoma encoder RTP session.\n");
+		return SWITCH_STATUS_SUCCESS;
+	}
+
+	if (encoded_frame.payload != codec->implementation->ianacode) {
+		switch_log_printf(SWITCH_CHANNEL_LOG, SWITCH_LOG_ERROR, "Read unexpected payload %d in Sangoma encoder RTP session, expecting %d\n", 
+				encoded_frame.payload, codec->implementation->ianacode);
+		return SWITCH_STATUS_FALSE;
+	}
+	memcpy(encoded_data, encoded_frame.data, encoded_frame.datalen);
+	*encoded_data_len = encoded_frame.datalen;
+
+	/* update encoding stats */
+	sess->encoder.rx++;
+
+	now_time = switch_micro_time_now();
+	if (!sess->encoder.last_rx_time) {
+		sess->encoder.last_rx_time = now_time;
+	} else {
+		difftime = now_time - sess->encoder.last_rx_time;
+		sess->encoder.avgrxus = sess->encoder.avgrxus ? ((sess->encoder.avgrxus + difftime)/2) : difftime;
+		sess->encoder.last_rx_time  = now_time;
+	}
+
+	/* check sequence and bump lost rx packets count if needed */
+	if (sess->encoder.lastrxseqno >= 0) {
+		if (encoded_frame.seq > (sess->encoder.lastrxseqno + 2) ) {
+			sess->encoder.rxlost += encoded_frame.seq - sess->encoder.lastrxseqno - 1;
+		}
+	}
+	sess->encoder.lastrxseqno = encoded_frame.seq;
+
+	return SWITCH_STATUS_SUCCESS;
+}
+
+static switch_status_t switch_sangoma_decode(switch_codec_t *codec,	/* codec session handle */
+										  switch_codec_t *other_codec,	/* what is this? */
+										  void *encoded_data,	/* data that we must decode into slinear and put it in decoded_data */
+										  uint32_t encoded_data_len,	/* length in bytes of the encoded data */
+										  uint32_t encoded_rate,	/* at which rate was the data encoded */
+										  void *decoded_data,	/* buffer where we must put the decoded data */
+										  uint32_t *decoded_data_len,	/* we must set this value to the size of the decoded data */
+										  uint32_t *decoded_rate,	/* rate of the decoded data */
+										  unsigned int *flag /* frame flag, see switch_frame_flag_enum_t */ )
+{
+	/* FS core checks the actual samples per second and microseconds per packet to determine the buffer size in the worst case scenario, no need to check
+	 * whether the buffer passed in by the core will be enough */
+	switch_frame_t encoded_frame;
+	switch_frame_t ulaw_frame;
+	switch_status_t sres;
+	switch_time_t now_time, difftime;
+	short *dbuf_linear;
+	int i = 0;
+	int res = 0;
+	struct sangoma_transcoding_session *sess = codec->private_info;
+
+	dbuf_linear = decoded_data;
+
+	/* start assuming we will not decode anything */
+	*decoded_data_len = 0;
+	if (*flag & SWITCH_CODEC_FLAG_SILENCE) {
+		memset(dbuf_linear, 0, codec->implementation->decoded_bytes_per_packet);
+		*decoded_data_len = codec->implementation->decoded_bytes_per_packet;
+		switch_log_printf(SWITCH_CHANNEL_LOG, SWITCH_LOG_DEBUG, "Returned silence on request\n");
+		return SWITCH_STATUS_SUCCESS;
+	}
+
+	/* initialize on first use */
+	if (!sess->decoder.txrtp) {
+		int err = 0;
+		switch_mutex_lock(g_sessions_lock);
+		err = sngtc_create_transcoding_session(&sess->decoder.request, &sess->decoder.reply, 0);
+		if (err) {
+			switch_mutex_unlock(g_sessions_lock);
+			switch_log_printf(SWITCH_CHANNEL_LOG, SWITCH_LOG_ERROR, "Failed to create Sangoma decoding session.\n");
+			return SWITCH_STATUS_FALSE;
+		}
+		sess->decoder.txrtp = sess->decoder.reply.tx_fd;
+		sess->decoder.rxrtp = sess->decoder.reply.rx_fd;
+		switch_mutex_unlock(g_sessions_lock);
+	}
+
+	/* do the writing */
+	memset(&encoded_frame, 0, sizeof(encoded_frame));
+	encoded_frame.source = __FUNCTION__;
+	encoded_frame.data = encoded_data;
+	encoded_frame.datalen = encoded_data_len;
+	encoded_frame.payload = codec->implementation->ianacode;
+
+	res = switch_rtp_write_frame(sess->decoder.txrtp, &encoded_frame);
+	if (-1 == res) {
+		switch_log_printf(SWITCH_CHANNEL_LOG, SWITCH_LOG_ERROR, "Failed to write to Sangoma decoder RTP session.\n");
+		return SWITCH_STATUS_FALSE;
+	}
+
+	if (res < encoded_data_len) {
+		switch_log_printf(SWITCH_CHANNEL_LOG, SWITCH_LOG_ERROR, 
+				"Requested to write %d bytes to Sangoma decoder RTP session, but wrote %d bytes.\n",
+			       	encoded_data_len, res);
+		return SWITCH_STATUS_FALSE;
+	}
+	sess->decoder.tx++;
+
+	/* do the reading */
+	memset(&ulaw_frame, 0, sizeof(ulaw_frame));
+	sres = switch_rtp_zerocopy_read_frame(sess->decoder.rxrtp, &ulaw_frame, SWITCH_IO_FLAG_NOBLOCK);
+	if (sres == SWITCH_STATUS_GENERR) {
+		switch_log_printf(SWITCH_CHANNEL_LOG, SWITCH_LOG_ERROR, "Failed to read on Sangoma decoder RTP session: %d\n", sres);
+		return SWITCH_STATUS_FALSE;
+	}
+
+	if (0 == ulaw_frame.datalen) {
+		switch_log_printf(SWITCH_CHANNEL_LOG, SWITCH_LOG_DEBUG, "No output on Sangoma decoder RTP session.\n");
+		return SWITCH_STATUS_SUCCESS;
+	}
+
+	if (ulaw_frame.payload != IANA_ULAW) { 
+		switch_log_printf(SWITCH_CHANNEL_LOG, SWITCH_LOG_ERROR, "Read unexpected payload %d in Sangoma decoder RTP session, expecting %d\n", 
+				ulaw_frame.payload, IANA_ULAW);
+		return SWITCH_STATUS_FALSE;
+	}
+
+	/* transcode to linear */
+	for (i = 0; i < ulaw_frame.datalen; i++) {
+		dbuf_linear[i] = ulaw_to_linear(((char *)ulaw_frame.data)[i]);
+	}
+	*decoded_data_len = i * 2;
+
+	/* update decoding stats */
+	sess->decoder.rx++;
+
+	now_time = switch_micro_time_now();
+	if (!sess->decoder.last_rx_time) {
+		sess->decoder.last_rx_time = now_time;
+	} else {
+		difftime = now_time - sess->decoder.last_rx_time;
+		sess->decoder.avgrxus = sess->decoder.avgrxus ? ((sess->decoder.avgrxus + difftime)/2) : difftime;
+		sess->decoder.last_rx_time = now_time;
+	}
+
+	/* check sequence and bump lost rx packets count if needed */
+	if (sess->decoder.lastrxseqno >= 0) {
+		if (ulaw_frame.seq > (sess->decoder.lastrxseqno + 2) ) {
+			sess->decoder.rxlost += ulaw_frame.seq - sess->decoder.lastrxseqno - 1;
+		}
+	}
+	sess->decoder.lastrxseqno = ulaw_frame.seq;
+
+	return SWITCH_STATUS_SUCCESS;
+}
+
+static switch_status_t switch_sangoma_destroy(switch_codec_t *codec)
+{
+	struct sangoma_transcoding_session *sess = codec->private_info;
+	/* things that you may do here is closing files, sockets or other resources used during the codec session 
+	 * no need to free memory allocated from the pool though, the owner of the pool takes care of that */
+	switch_log_printf(SWITCH_CHANNEL_LOG, SWITCH_LOG_DEBUG, "Sangoma destroy called.\n");
+	
+	switch_mutex_lock(g_sessions_lock);
+
+	if (sess->encoder.reply.codec_rtp_session) {
+		sngtc_destroy_transcoding_session(sess->encoder.reply.codec_rtp_session);
+	}
+	if (sess->decoder.reply.codec_rtp_session) {
+		sngtc_destroy_transcoding_session(sess->decoder.reply.codec_rtp_session);
+	}
+	
+	switch_core_hash_delete(g_sessions_hash, sess->hashkey);
+
+	switch_mutex_unlock(g_sessions_lock);
+	return SWITCH_STATUS_SUCCESS;
+}
+
+static struct sangoma_transcoding_session *sangoma_find_session(unsigned long sessid)
+{
+	char hashkey[50];
+	snprintf(hashkey, sizeof(hashkey), SANGOMA_SESS_HASH_KEY_FORMAT, sessid);
+	return switch_core_hash_find(g_sessions_hash, hashkey);
+}
+
+static void sangoma_print_stats(switch_stream_handle_t *stream, switch_rtp_numbers_t *stats)
+{
+	stream->write_function(stream, "Raw bytes: %lu\n", stats->raw_bytes);
+	stream->write_function(stream, "Media bytes: %lu\n", stats->media_bytes);
+	stream->write_function(stream, "Packet count: %lu\n", stats->packet_count);
+	stream->write_function(stream, "Media packet count: %lu\n", stats->media_packet_count);
+	stream->write_function(stream, "Skip packet count: %lu\n", stats->skip_packet_count);
+	stream->write_function(stream, "Jitter buffer packet count: %lu\n", stats->jb_packet_count);
+	stream->write_function(stream, "DTMF packet count: %lu\n", stats->dtmf_packet_count);
+	stream->write_function(stream, "CNG packet count: %lu\n", stats->cng_packet_count);
+	stream->write_function(stream, "Flush packet count: %lu\n\n\n", stats->flush_packet_count);
+}
+
+#define SANGOMA_SYNTAX "settings|sessions|stats <session>"
+SWITCH_STANDARD_API(sangoma_function)
+{
+	char *argv[10] = { 0 };
+	int argc = 0;
+	char *mycmd = NULL;
+
+	if (zstr(cmd)) {
+		stream->write_function(stream, "%s", SANGOMA_SYNTAX);
+		return SWITCH_STATUS_SUCCESS;
+	}
+
+	if (!(mycmd = strdup(cmd))) {
+		return SWITCH_STATUS_MEMERR;
+	}
+
+	if (!(argc = switch_separate_string(mycmd, ' ', argv, (sizeof(argv) / sizeof(argv[0])))) || !argv[0]) {
+		stream->write_function(stream, "%s", SANGOMA_SYNTAX);
+		switch_safe_free(mycmd);
+		return SWITCH_STATUS_SUCCESS;
+	}
+
+#if 0
+FIXME: settings per vocallo
+	if (!strcasecmp(argv[0], "settings")) {
+		char ip_buff[50];
+		stream->write_function(stream, "UDP port range: %d\n", g_sangoma_baseudp);
+
+		stream->write_function(stream, "localaddr: %s\n", 
+				switch_inet_ntop(AF_INET, &g_sangoma_local_ip, ip_buff, sizeof(ip_buff)));
+
+		stream->write_function(stream, "vocallohost: %s\n", 
+				switch_inet_ntop(AF_INET, &g_sangoma_vocallo_ip, ip_buff, sizeof(ip_buff)));
+
+		stream->write_function(stream, "netmask: %s\n", 
+				switch_inet_ntop(AF_INET, &g_sangoma_local_netmask, ip_buff, sizeof(ip_buff)));
+
+	} else if (!strcasecmp(argv[0], "sessions")) {
+#endif
+	if (!strcasecmp(argv[0], "sessions")) {
+		/* iterate over sessions hash */
+		switch_hash_index_t *hi;
+		const void *var;
+		void *val;
+		unsigned totalsess = 0;
+		switch_mutex_lock(g_sessions_lock);
+#define STATS_FORMAT "%-10.10s %-10.10s %-10.10s %-10.10s %-10.10s %-10.10s %-10.10s %-10.10s %-10.10s %-10.10s %-15.15s %-15.15s\n"
+		stream->write_function(stream, STATS_FORMAT,
+				"Session", "Codec", "Enc", "Dec", "Enc Tx", "Enc Rx", "Dec Tx", "Dec Rx", "Enc Lost", "Dec Lost", "Enc AvgRxMs", "Dec AvgRxMs");
+		for (hi = switch_hash_first(NULL, g_sessions_hash); hi; hi = switch_hash_next(hi)) {
+			struct sangoma_transcoding_session *sess;
+			char sessid_str[25];
+			char encoder_tx_str[25];
+			char encoder_rx_str[25];
+			char decoder_tx_str[25];
+			char decoder_rx_str[25];
+			char encoder_lostrx_str[25];
+			char decoder_lostrx_str[25];
+			char encoder_avgrxus_str[25];
+			char decoder_avgrxus_str[25];
+
+			switch_hash_this(hi, &var, NULL, &val);
+			sess = val;
+
+			snprintf(sessid_str, sizeof(sessid_str), "%lu", sess->sessid);
+			snprintf(encoder_tx_str, sizeof(encoder_tx_str), "%lu", sess->encoder.tx);
+			snprintf(encoder_rx_str, sizeof(encoder_rx_str), "%lu", sess->encoder.rx);
+			snprintf(decoder_tx_str, sizeof(decoder_tx_str), "%lu", sess->decoder.tx);
+			snprintf(decoder_rx_str, sizeof(decoder_rx_str), "%lu", sess->decoder.rx);
+			snprintf(encoder_lostrx_str, sizeof(encoder_lostrx_str), "%lu", sess->encoder.rxlost);
+			snprintf(decoder_lostrx_str, sizeof(decoder_lostrx_str), "%lu", sess->decoder.rxlost);
+			snprintf(encoder_avgrxus_str, sizeof(encoder_avgrxus_str), "%ld", (long)(sess->encoder.avgrxus/1000));
+			snprintf(decoder_avgrxus_str, sizeof(encoder_avgrxus_str), "%ld", (long)(sess->decoder.avgrxus/1000));
+
+
+			stream->write_function(stream, STATS_FORMAT,
+					sessid_str, 
+					sess->impl->iananame,
+					sess->encoder.txrtp ? "Yes" : "No", 
+					sess->decoder.txrtp ? "Yes" : "No",
+					encoder_tx_str,
+					encoder_rx_str,
+					decoder_tx_str,
+					decoder_rx_str,
+					encoder_lostrx_str,
+					decoder_lostrx_str,
+					encoder_avgrxus_str,
+					decoder_avgrxus_str);
+			totalsess++;
+		}
+		switch_mutex_unlock(g_sessions_lock);
+		stream->write_function(stream, "Total sessions: %d\n", totalsess);
+	} else if (!strcasecmp(argv[0], "stats")) {
+		struct sangoma_transcoding_session *sess;
+		unsigned long sessid = 0;
+		switch_rtp_stats_t *stats = NULL;
+		int ret = 0;
+		if (argc < 2) {
+			stream->write_function(stream, "%s", SANGOMA_SYNTAX);
+			goto done;
+		} 
+		ret = sscanf(argv[1], "%lu", &sessid);
+		if (ret != 1) {
+			stream->write_function(stream, "%s", SANGOMA_SYNTAX);
+			goto done;
+		} 
+		sess = sangoma_find_session(sessid);
+		if (!sess) {
+			stream->write_function(stream, "Failed to find session %lu\n", sessid);
+			goto done;
+		}
+		stream->write_function(stream, "Session: %lu\n", sessid);
+
+		if (sess->encoder.rxrtp) {
+			stats = switch_rtp_get_stats(sess->encoder.rxrtp, NULL);
+			stream->write_function(stream, "-- Encoder Inbound Stats --\n");
+			sangoma_print_stats(stream, &stats->inbound);
+			
+
+			stats = switch_rtp_get_stats(sess->encoder.txrtp, NULL);
+			stream->write_function(stream, "-- Encoder Outbound Stats --\n");
+			sangoma_print_stats(stream, &stats->outbound);
+		}
+
+		if (sess->decoder.rxrtp) {
+			stats = switch_rtp_get_stats(sess->decoder.rxrtp, NULL);
+			stream->write_function(stream, "-- Decoder Inbound Stats --\n");
+			sangoma_print_stats(stream, &stats->inbound);
+
+			stats = switch_rtp_get_stats(sess->decoder.txrtp, NULL);
+			stream->write_function(stream, "-- Decoder Outbound Stats --\n");
+			sangoma_print_stats(stream, &stats->outbound);
+		}
+	} else {
+		stream->write_function(stream, "Unknown Command [%s]\n", argv[0]);
+	}
+
+done:
+	switch_safe_free(mycmd);
+
+	return SWITCH_STATUS_SUCCESS;
+}
+
+static int sangoma_logger(int level, char *fmt, ...)
+{
+	char *data;
+	int ret = 0;
+	va_list ap;
+
+	va_start(ap, fmt);
+	ret = switch_vasprintf(&data, fmt, ap);
+	if (ret == -1) {
+		return -1;
+	}
+
+	switch (level) {
+	case SNGTC_LOGLEVEL_DEBUG:
+		switch_log_printf(SWITCH_CHANNEL_LOG, SWITCH_LOG_DEBUG, "%s\n", data);
+		break;
+	case SNGTC_LOGLEVEL_WARN:
+		switch_log_printf(SWITCH_CHANNEL_LOG, SWITCH_LOG_WARNING, "%s\n", data);
+		break;
+	case SNGTC_LOGLEVEL_INFO:
+		switch_log_printf(SWITCH_CHANNEL_LOG, SWITCH_LOG_INFO, "%s\n", data);
+		break;
+	case SNGTC_LOGLEVEL_STATS:
+		break;
+	case SNGTC_LOGLEVEL_ERROR:
+		switch_log_printf(SWITCH_CHANNEL_LOG, SWITCH_LOG_ERROR, "%s\n", data);
+		break;
+	case SNGTC_LOGLEVEL_CRIT:
+		switch_log_printf(SWITCH_CHANNEL_LOG, SWITCH_LOG_CRIT, "%s\n", data);
+		break;
+	default:
+		switch_log_printf(SWITCH_CHANNEL_LOG, SWITCH_LOG_WARNING, "Unexpected msg with loglevel %d: %s\n", level, data);
+	}
+
+	free(data);
+	return 0;
+}
+
+static int load_nic_network_information(const char *nic, sngtc_host_nic_vocallo_cfg_t *cfg)
+{
+#ifdef __linux__
+	struct ifreq ifr;
+	int sock;
+	char *mac;
+	int j = 0, k = 0, ret = 0;
+	
+	sock = socket(PF_INET, SOCK_STREAM, 0);
+	if (-1 == sock) {
+		switch_log_printf(SWITCH_CHANNEL_LOG, SWITCH_LOG_ERROR, 
+			"Failed to create socket to query network configuration for NIC %s: %s\n", nic, strerror(errno));
+		return -1;
+	}
+
+	strncpy(ifr.ifr_name, nic, sizeof(ifr.ifr_name)-1);
+	ifr.ifr_name[sizeof(ifr.ifr_name)-1] = '\0';
+
+	if (-1 == ioctl(sock, SIOCGIFADDR, &ifr)) {
+		switch_log_printf(SWITCH_CHANNEL_LOG, SWITCH_LOG_ERROR, "Failed to query IP address for NIC %s: %s\n", nic, strerror(errno));
+		ret = -1;
+		goto done;
+	}
+	cfg->host_ip = ntohl(((struct sockaddr_in *)&ifr.ifr_addr)->sin_addr.s_addr);
+
+	if (-1 == ioctl(sock, SIOCGIFNETMASK, &ifr)) {
+		switch_log_printf(SWITCH_CHANNEL_LOG,  SWITCH_LOG_ERROR, "Failed to query network address for NIC %s: %s\n", nic, strerror(errno));
+		ret = -1;
+		goto done;
+	}
+	cfg->host_ip_netmask = ntohl(((struct sockaddr_in *)&ifr.ifr_netmask)->sin_addr.s_addr);
+
+	if (-1 == ioctl(sock, SIOCGIFHWADDR, &ifr)) {
+		switch_log_printf(SWITCH_CHANNEL_LOG, SWITCH_LOG_ERROR, "Failed to query HW address for NIC %s: %s\n", nic, strerror(errno));
+		ret = -1;
+		goto done;
+	}
+
+	mac = cfg->host_mac.mac_str;
+	for (j = 0, k = 0; j < 6; j++) {
+		k += snprintf(mac + k, sizeof(cfg->host_mac.mac_str) - k, j ? "-%02X" : "%02X",
+				(int)(unsigned int)(unsigned char)ifr.ifr_hwaddr.sa_data[j]);
+	}
+	mac[sizeof(cfg->host_mac.mac_str)-1] = '\0';
+
+done:
+	close(sock);
+	return ret;
+#else
+	return 0;
+#endif
+}
+
+static int sangoma_parse_config(void)
+{
+	switch_xml_t cfg, settings, param, vocallos, xml, vocallo;
+	struct in_addr vocallo_base_ip;
+	char ipbuff[50];
+	char netbuff[50];
+	int vidx = 0;
+	int baseudp = 0;
+
+	switch_log_printf(SWITCH_CHANNEL_LOG, SWITCH_LOG_DEBUG, "Reading sangoma codec configuration\n");
+	if (!(xml = switch_xml_open_cfg(SANGOMA_TRANSCODE_CONFIG, &cfg, NULL))) {
+		switch_log_printf(SWITCH_CHANNEL_LOG, SWITCH_LOG_CRIT, "Failed to open sangoma codec configuration %s\n", SANGOMA_TRANSCODE_CONFIG);
+		return -1;
+	}
+
+	memset(&g_init_cfg, 0, sizeof(g_init_cfg));
+
+	if ((settings = switch_xml_child(cfg, "settings"))) {
+		/* nothing here yet */
+	}
+
+	if ((vocallos = switch_xml_child(cfg, "vocallos"))) {
+		for (vocallo = switch_xml_child(vocallos, "vocallo"); vocallo; vocallo = vocallo->next) {
+			const char *name = switch_xml_attr(vocallo, "name");
+			if (!name) {
+				switch_log_printf(SWITCH_CHANNEL_LOG, SWITCH_LOG_WARNING, "Sangoma vocallo found with no name= attribute, ignoring!\n");
+				continue;
+			}
+
+			if (load_nic_network_information(name, &g_init_cfg.host_nic_vocallo_cfg[vidx])) {
+				switch_log_printf(SWITCH_CHANNEL_LOG, SWITCH_LOG_WARNING, 
+						"Ignoring vocallo %s, failed to retrieve its network configuration\n", name);
+				continue;
+			}
+
+			switch_log_printf(SWITCH_CHANNEL_LOG, SWITCH_LOG_INFO, "Configuring vocallo %s\n", name);
+
+			g_init_cfg.host_nic_vocallo_cfg[vidx].vocallo_base_udp_port = SANGOMA_DEFAULT_UDP_PORT;
+			for (param = switch_xml_child(vocallo, "param"); param; param = param->next) {
+				char *var = (char *)switch_xml_attr_soft(param, "name");
+				char *val = (char *)switch_xml_attr_soft(param, "value");
+
+				/* starting UDP port to be used by the vocallo modules */
+				if (!strcasecmp(var, "baseudp")) {
+					switch_log_printf(SWITCH_CHANNEL_LOG, SWITCH_LOG_DEBUG, "Found Sangoma codec base udp port %s\n", val);
+					baseudp = atoi(val);
+					if (baseudp < SANGOMA_MIN_UDP_PORT || baseudp > SANGOMA_MAX_UDP_PORT) {
+						switch_log_printf(SWITCH_CHANNEL_LOG, SWITCH_LOG_WARNING, 
+								"Invalid Sangoma codec base udp port %s, using default %d\n", 
+								val, SANGOMA_DEFAULT_UDP_PORT);
+						break;
+					}
+					g_init_cfg.host_nic_vocallo_cfg[vidx].vocallo_base_udp_port = baseudp;
+				}
+				else if (!strcasecmp(var, "vocalloaddr")) {
+					switch_log_printf(SWITCH_CHANNEL_LOG, SWITCH_LOG_DEBUG, "Found Sangoma codec vocallo addr %s\n", val);
+					if (switch_inet_pton(AF_INET, val, &vocallo_base_ip) <= 0) {
+						switch_log_printf(SWITCH_CHANNEL_LOG, SWITCH_LOG_WARNING, "Invalid Sangoma codec vocallo addr %s\n", val);
+						break;
+					}
+					g_init_cfg.host_nic_vocallo_cfg[vidx].vocallo_ip = ntohl(vocallo_base_ip.s_addr);
+				} else {
+					switch_log_printf(SWITCH_CHANNEL_LOG, SWITCH_LOG_WARNING, "Ignored unknown Sangoma codec setting %s\n", val);
+				}
+			}
+
+			if (!g_init_cfg.host_nic_vocallo_cfg[vidx].vocallo_ip) {
+				switch_log_printf(SWITCH_CHANNEL_LOG, SWITCH_LOG_WARNING, "Ignoring vocallo %s, no valid address was configured\n", name);
+				continue;
+			}
+
+			switch_log_printf(SWITCH_CHANNEL_LOG, SWITCH_LOG_NOTICE, 
+					"Sangoma transcoding interface %s using IP address %s, netmask %s\n", 
+					name, 
+					switch_inet_ntop(AF_INET, &g_init_cfg.host_nic_vocallo_cfg[vidx].host_ip, ipbuff, sizeof(ipbuff)),
+					switch_inet_ntop(AF_INET, &g_init_cfg.host_nic_vocallo_cfg[vidx].host_ip_netmask, netbuff, sizeof(netbuff)));
+			vidx++;
+		}
+	} else {
+		switch_log_printf(SWITCH_CHANNEL_LOG, SWITCH_LOG_ERROR, "No <vocallos> section found in configuration file %s\n", SANGOMA_TRANSCODE_CONFIG);
+	}
+
+	switch_xml_free(xml);
+
+	if (!vidx) {
+		switch_log_printf(SWITCH_CHANNEL_LOG, SWITCH_LOG_ERROR, 
+		"No vocallos were configured, make sure there is at least one <vocallo> in %s.\n", SANGOMA_TRANSCODE_CONFIG);
+	}
+
+	g_init_cfg.host_nic_vocallo_sz = vidx;
+
+	return 0;
+}
+
+SWITCH_MODULE_SHUTDOWN_FUNCTION(mod_sangoma_codec_shutdown)
+{
+	switch_core_hash_destroy(&g_sessions_hash);
+	return SWITCH_STATUS_SUCCESS;
+}
+
+SWITCH_MODULE_LOAD_FUNCTION(mod_sangoma_codec_load)
+{
+	/* the codec interface that will be registered with the core */
+	switch_codec_interface_t *codec_interface = NULL;
+	switch_api_interface_t *api_interface = NULL;
+	int i = 0, c = 0;
+	int detected = 0, activated = 0;
+
+	/* make sure we have valid configuration */
+	if (sangoma_parse_config()) {
+		return SWITCH_STATUS_FALSE;
+	}
+
+	g_init_cfg.log = sangoma_logger;
+	g_init_cfg.create_rtp = sangoma_create_rtp;
+	g_init_cfg.destroy_rtp = sangoma_destroy_rtp;
+
+	if (sngtc_detect_init_modules(&g_init_cfg, &detected)) {
+		switch_log_printf(SWITCH_CHANNEL_LOG, SWITCH_LOG_ERROR, "Failed to detect vocallo modules\n");
+		return SWITCH_STATUS_FALSE;
+	}
+    
+	if (sngtc_activate_modules(&g_init_cfg, &activated)) {
+		switch_log_printf(SWITCH_CHANNEL_LOG, SWITCH_LOG_ERROR, "Failed to activate vocallo modules\n");
+		return SWITCH_STATUS_FALSE;
+	}
+	switch_log_printf(SWITCH_CHANNEL_LOG, SWITCH_LOG_NOTICE, "Detected %d and activated %d Sangoma codec vocallo modules\n", detected, activated);
+
+	switch_mutex_init(&g_sessions_lock, SWITCH_MUTEX_UNNESTED, pool);
+
+	switch_core_hash_init(&g_sessions_hash, pool);
+
+	*module_interface = switch_loadable_module_create_module_interface(pool, modname);
+
+	for (c = 0; g_codec_map[c].codec_id != -1; c++) {
+		/* SWITCH_ADD_CODEC allocates a codec interface structure from the pool the core gave us and adds it to the internal interface 
+		 * list the core keeps, gets a codec id and set the given codec name to it.
+		 * At this point there is an empty shell codec interface registered, but not yet implementations */
+		SWITCH_ADD_CODEC(codec_interface, g_codec_map[c].fs_name);
+
+		/* Now add as many codec implementations as needed, just up to 40ms for now */
+		for (i = 1; i <= 4; i++) {
+
+			if ((g_codec_map[c].maxms/10) < i) {
+				continue;
+			}
+
+			switch_core_codec_add_implementation(pool, codec_interface,	/* the codec interface we allocated and we want to register with the core */
+							 SWITCH_CODEC_TYPE_AUDIO, /* enumeration defining the type of the codec */
+							 g_codec_map[c].iana,	/* the IANA code number, ie http://www.iana.org/assignments/rtp-parameters */
+							 g_codec_map[c].iana_name, /* the IANA code name */
+							 NULL,	/* default fmtp to send (can be overridden by the init function), fmtp is used in SDP for format specific parameters */
+							 8000,	/* samples transferred per second */
+							 8000,	/* actual samples transferred per second */
+							 g_codec_map[c].bps,	/* bits transferred per second */
+							 g_codec_map[c].mpf * i, /* microseconds per frame */
+							 g_codec_map[c].spf * i, /* samples per frame */
+							 g_codec_map[c].bpfd * i, /* number of bytes per frame decompressed */
+							 g_codec_map[c].bpfc * i, /* number of bytes per frame compressed */
+							 1,	/* number of channels represented */
+							 g_codec_map[c].spf * i, /* number of frames per network packet (I dont think this is used at all) */
+							 switch_sangoma_init,	/* function to initialize a codec session using this implementation */
+							 switch_sangoma_encode,	/* function to encode slinear data into encoded data */
+							 switch_sangoma_decode,	/* function to decode encoded data into slinear data */
+							 switch_sangoma_destroy); /* deinitalize a codec handle using this implementation */
+
+		}
+	}
+
+
+	SWITCH_ADD_API(api_interface, "sangoma_codec", "Sangoma Codec Commands", sangoma_function, SANGOMA_SYNTAX);
+	switch_console_set_complete("add sangoma_codec");
+	switch_console_set_complete("add sangoma_codec settings");
+	switch_console_set_complete("add sangoma_codec sessions");
+	switch_console_set_complete("add sangoma_codec stats");
+
+	return SWITCH_STATUS_SUCCESS;
+}
+
+/* For Emacs:
+ * Local Variables:
+ * mode:c
+ * indent-tabs-mode:t
+ * tab-width:4
+ * c-basic-offset:4
+ * End:
+ * For VIM:
+ * vim:set softtabstop=4 shiftwidth=4 tabstop=4:
+ */