text: /*
   * FreeSWITCH Modular Media Switching Software Library / Soft-Switch Application
   * Copyright (C) 2005-2014, Anthony Minessale II <anthm@freeswitch.org>
   *
   * Version: MPL 1.1
   *
   * The contents of this file are subject to the Mozilla Public License Version
   * 1.1 (the "License"); you may not use this file except in compliance with
   * the License. You may obtain a copy of the License at
   * http://www.mozilla.org/MPL/
   *
   * Software distributed under the License is distributed on an "AS IS" basis,
   * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
   * for the specific language governing rights and limitations under the
   * License.
   *
   * The Original Code is FreeSWITCH Modular Media Switching Software Library
   *
   * The Initial Developer of the Original Code is
   * Brian West <brian@freeswitch.org>
   * Portions created by the Initial Developer are Copyright (C)
   * the Initial Developer. All Rights Reserved.
   *
   * Contributor(s):
   * Mathieu Rene <mrene@avgs.ca>
   * Dragos Oancea <droancea@yahoo.com>
   *
   * mod_codec2 -- FreeSWITCH CODEC2 Module
   *
   */
  
  #include <switch.h>
  #include <codec2/codec2.h>
  
  /* Uncomment to log input/output data for debugging
  #define LOG_DATA
  #define CODEC2_DEBUG
  */
  
  #define CODEC2_SAMPLES_PER_FRAME 160
  
  #ifdef CODEC2_DEBUG
  #define codec2_assert(_x) switch_assert(_x)
  #else
  #define codec2_assert(_x)
  #endif
  
  SWITCH_MODULE_LOAD_FUNCTION(mod_codec2_load);
  
  SWITCH_MODULE_DEFINITION(mod_codec2, mod_codec2_load, NULL, NULL);
  
  struct codec2_context {
  	void *encoder;
  	void *decoder;
  	int mode; /* codec2 operation mode */
  	int nbit; /* nr of bits per frame */
  	int nbyte; /* nr of bytes per frame */
  	int nsam; /* nr of samples per frame */
  #ifdef LOG_DATA
  	FILE *encoder_in;
  	FILE *encoder_out;
  	FILE *encoder_out_unpacked;
  	FILE *decoder_in;
  	FILE *decoder_in_unpacked;
  	FILE *decoder_out;
  #endif
  };
  
  struct {
  	int mode;
  	int ptime;
  	int samples_per_frame;
  } codec2_prefs;
  
  #ifdef LOG_DATA
  static int c2_count = 0;
  #endif
  
  static switch_status_t switch_codec2_init(switch_codec_t *codec, switch_codec_flag_t flags, const switch_codec_settings_t *codec_settings)
  {
  	uint32_t encoding, decoding;
  	struct codec2_context *context = NULL;
  
  	encoding = (flags & SWITCH_CODEC_FLAG_ENCODE);
  	decoding = (flags & SWITCH_CODEC_FLAG_DECODE);
  
  	if (!(encoding || decoding)) {
  		return SWITCH_STATUS_FALSE;
  	}
  
  	if (!(context = switch_core_alloc(codec->memory_pool, sizeof(*context)))) {
  		return SWITCH_STATUS_FALSE;
  	}
  
  	if (!codec2_prefs.mode) {
  		codec2_prefs.mode = CODEC2_MODE_2400;
  	}
  
  	if (codec2_prefs.mode == 3200) {
  			context->mode = CODEC2_MODE_3200;
  	} else if (codec2_prefs.mode == 2400) {
  			context->mode = CODEC2_MODE_2400;
  	} else if (codec2_prefs.mode == 1400) {
  			context->mode = CODEC2_MODE_1400;
  	} else if (codec2_prefs.mode == 1200) {
  			context->mode = CODEC2_MODE_1200;
  	} else {
  		/* 3200 might be better for VOIP, but forcing 2400 for backwards compatibility  */
  		switch_log_printf(SWITCH_CHANNEL_LOG, SWITCH_LOG_ERROR, "mode not supported, forcing CODEC2_MODE_2400. You can try mode 3200 too!\n");
  		context->mode = CODEC2_MODE_2400;
  	}
  
  	if (encoding) {
  		context->encoder = codec2_create(context->mode);
  	}
  
  	if (decoding) {
  		context->decoder = codec2_create(context->mode);
  	}
  
  	context->nsam = codec2_samples_per_frame(context->encoder);
  	if (!context->nsam) {
  		context->nsam = CODEC2_SAMPLES_PER_FRAME;
  	}
  	context->nbit = codec2_bits_per_frame(context->encoder);
  	context->nbyte = (context->nbit + 7) / 8;
  
  	codec->private_info = context;
  
  #ifdef LOG_DATA
  	{
  
  		int c = c2_count++;
  		char buf[1024];
  
  		switch_log_printf(SWITCH_CHANNEL_LOG, SWITCH_LOG_CONSOLE, "Logging as /tmp/c2-%d-*\n", c);
  
  		if (encoding) {
  			snprintf(buf, sizeof(buf), "/tmp/c2-%d-enc-in", c);
  			context->encoder_in = fopen(buf, "w");
  
  			snprintf(buf, sizeof(buf), "/tmp/c2-%d-enc-out", c);
  			context->encoder_out = fopen(buf, "w");
  
  			snprintf(buf, sizeof(buf), "/tmp/c2-%d-enc-out-unpacked", c);
  			context->encoder_out_unpacked = fopen(buf, "w");
  		}
  		if (decoding) {
  			snprintf(buf, sizeof(buf), "/tmp/c2-%d-dec-in", c);
  			context->decoder_in = fopen(buf, "w");
  
  			snprintf(buf, sizeof(buf), "/tmp/c2-%d-dec-out", c);
  			context->decoder_out = fopen(buf, "w");
  
  			snprintf(buf, sizeof(buf), "/tmp/c2-%d-dec-out-unpacked", c);
  			context->decoder_in_unpacked = fopen(buf, "w");
  		}
  	}
  #endif
  
  	return SWITCH_STATUS_SUCCESS;
  }
  
  static switch_status_t switch_codec2_encode(switch_codec_t *codec, switch_codec_t *other_codec,
  										  void *decoded_data,
  										  uint32_t decoded_data_len,
  										  uint32_t decoded_rate,
  										  void *encoded_data,
  										  uint32_t *encoded_data_len,
  										  uint32_t *encoded_rate,
  										  unsigned int *flag)
  {
  	struct codec2_context *context = codec->private_info;
  
  	codec2_assert(decoded_data_len == context->nsam * 2);
  
  #ifdef LOG_DATA
  	fwrite(decoded_data, decoded_data_len, 1, context->encoder_in);
  	fflush(context->encoder_in);
  #endif
  
  	codec2_encode(context->encoder, encoded_data, decoded_data);
  
  #ifdef LOG_DATA
  	fwrite(encode_buf, sizeof(encode_buf), 1, context->encoder_out_unpacked);
  	fflush(context->encoder_out_unpacked);
  	fwrite(encoded_data, context->nbyte, 1, context->encoder_out);
  	fflush(context->encoder_out);
  #endif
  
  	*encoded_data_len = context->nbyte;
  
  	return SWITCH_STATUS_SUCCESS;
  }
  
  static switch_status_t switch_codec2_decode(switch_codec_t *codec,
  										  switch_codec_t *other_codec,
  										  void *encoded_data,
  										  uint32_t encoded_data_len,
  										  uint32_t encoded_rate,
  										  void *decoded_data,
  										  uint32_t *decoded_data_len,
  										  uint32_t *decoded_rate,
  										  unsigned int *flag)
  {
  	struct codec2_context *context = codec->private_info;
  
  	codec2_assert(encoded_data_len == 8);
  
  #ifdef LOG_DATA
  	fwrite(encoded_data, encoded_data_len, 1, context->decoder_in);
  	fflush(context->decoder_in);
  	fwrite(bits, sizeof(bits), 1, context->decoder_in_unpacked);
  	fflush(context->decoder_in_unpacked);
  #endif
  
  	codec2_decode(context->decoder, decoded_data, encoded_data);
  
  #ifdef LOG_DATA
  	fwrite(decoded_data, context->nsam, 2, context->decoder_out);
  	fflush(context->decoder_out);
  #endif
  
  	*decoded_data_len = context->nsam * 2; /* eg: 160 samples for 3200,2400 */
  
  	return SWITCH_STATUS_SUCCESS;
  }
  
  static switch_status_t switch_codec2_destroy(switch_codec_t *codec)
  {
  	struct codec2_context *context = codec->private_info;
  
  	codec2_destroy(context->encoder);
  	codec2_destroy(context->decoder);
  
  	context->encoder = NULL;
  	context->decoder = NULL;
  
  #ifdef LOG_DATA
  	if (context->encoder_in) {
  		fclose(context->encoder_in);
  	}
  	if (context->encoder_out) {
  		fclose(context->encoder_out);
  	}
  	if (context->encoder_out_unpacked) {
  		fclose(context->encoder_out_unpacked);
  	}
  	if (context->decoder_in) {
  		fclose(context->decoder_in);
  	}
  	if (context->decoder_in_unpacked) {
  		fclose(context->decoder_in_unpacked);
  	}
  	if (context->decoder_out) {
  		fclose(context->decoder_out);
  	}
  #endif
  
  	return SWITCH_STATUS_SUCCESS;
  }
  
  static switch_status_t codec2_load_config(switch_bool_t reload) {
  
  	char *cf = "codec2.conf";
  	switch_xml_t cfg, xml = NULL, param, settings;
  	switch_status_t status = SWITCH_STATUS_SUCCESS;
  
  	codec2_prefs.mode = 2400 ;
  
  	if (!(xml = switch_xml_open_cfg(cf, &cfg, NULL))) {
  		switch_log_printf(SWITCH_CHANNEL_LOG, SWITCH_LOG_ERROR, "Opening of %s failed\n", cf);
  		return status;
  	}
  
  	if ((settings = switch_xml_child(cfg, "settings"))) {
  		for (param = switch_xml_child(settings, "param"); param; param = param->next) {
  			char *key = (char *) switch_xml_attr_soft(param, "name");
  			char *val = (char *) switch_xml_attr_soft(param, "value");
  
  			if (!strcasecmp(key, "mode") && !zstr(val)) {
  				codec2_prefs.mode = atoi(val);
  			}
  		}
  	}
  
  	if (xml) {
  		switch_xml_free(xml);
  	}
  
  	return status;
  }
  
  SWITCH_MODULE_LOAD_FUNCTION(mod_codec2_load)
  {
  	switch_codec_interface_t *codec_interface;
  	switch_status_t status = SWITCH_STATUS_SUCCESS;
  
  	if ((status = codec2_load_config(SWITCH_FALSE)) != SWITCH_STATUS_SUCCESS) {
  		return status;
  	}
  
  	*module_interface = switch_loadable_module_create_module_interface(pool, modname);
  
  	/*there is no API call to retrieve ptime per mode, so hardcoding here*/
  	if ((codec2_prefs.mode == 3200) ||(codec2_prefs.mode == 2400)) {
  		codec2_prefs.ptime = 20000;
  		codec2_prefs.samples_per_frame = CODEC2_SAMPLES_PER_FRAME;
  	} else {
  		codec2_prefs.ptime = 40000;
  		codec2_prefs.samples_per_frame = CODEC2_SAMPLES_PER_FRAME * 2;
  	}
  
  	SWITCH_ADD_CODEC(codec_interface, "CODEC2 3200/2400/1400/1200bps");
  
  	switch_core_codec_add_implementation(pool, codec_interface,
  							 SWITCH_CODEC_TYPE_AUDIO,
  							 111,
  							 "CODEC2",
  							 NULL,
  							 8000, /* samples/sec */
  							 8000, /* samples/sec */
  							 codec2_prefs.mode, /* bps */
  							 codec2_prefs.ptime, /* ptime */
  							 codec2_prefs.samples_per_frame,	/* samples decoded */
  							 codec2_prefs.samples_per_frame * 2,	/* bytes decoded */
  							 0,	/* bytes encoded */
  							 1,	/* channels */
  							 1,	/* frames/packet */
  							 switch_codec2_init,
  							 switch_codec2_encode,
  							 switch_codec2_decode,
  							 switch_codec2_destroy);
  
  	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 noet:
   */
  