OPENZAP-238: [freetdm] Several core and gsm improvements

* Add error handing in mod_freetdm for ftdm trace failures

* Allow freetdm signaling modules to specify a destroy function

* Added conditional forwarding to the freetdm gsm module
  Just specify the conditional-forwarding-number gsm parameter in freetdm.conf.xml

* Added new 'gsm call' freetdm command for raw GSM calls which can be
  used to enable/disabling network features (e.g call *93) without
  having to resort to use a full originate that requires routing the
  call somewhere when answered

* Miscelaneous cleanup of piggy coding style left over by one of the
  previous authors -_-

libs/freetdm/mod_freetdm/mod_freetdm.c

@@ -4936,6 +4936,7 @@ FTDM_CLI_DECLARE(ftdm_cmd_trace)
 	uint32_t chan_id = 0;
 	uint32_t span_id = 0;
 	uint32_t chan_count = 0;
+	ftdm_status_t status;
 	ftdm_span_t *span = NULL;
 	ftdm_channel_t *chan = NULL;
 
@@ -4964,17 +4965,39 @@ FTDM_CLI_DECLARE(ftdm_cmd_trace)
 
 	if (chan_id) {
 		chan = ftdm_span_get_channel(span, chan_id);
+
 		snprintf(tracepath, sizeof(tracepath), "%s-in-s%dc%d", argv[1], span_id, chan_id);
-		ftdm_channel_command(chan, FTDM_COMMAND_TRACE_INPUT, tracepath);
+		status = ftdm_channel_command(chan, FTDM_COMMAND_TRACE_INPUT, tracepath);
+		if (status != FTDM_SUCCESS) {
+			stream->write_function(stream, "-ERR failed to enable input trace at path %s\n", tracepath);
+			goto end;
+		}
+
 		snprintf(tracepath, sizeof(tracepath), "%s-out-s%dc%d", argv[1], span_id, chan_id);
-		ftdm_channel_command(chan, FTDM_COMMAND_TRACE_OUTPUT, tracepath);
+		status = ftdm_channel_command(chan, FTDM_COMMAND_TRACE_OUTPUT, tracepath);
+		if (status != FTDM_SUCCESS) {
+			stream->write_function(stream, "-ERR failed to enable output trace at path %s\n", tracepath);
+			ftdm_channel_command(chan, FTDM_COMMAND_TRACE_END_ALL, NULL);
+			goto end;
+		}
 	} else {
 		for (i = 1; i <= chan_count; i++) {
 			chan = ftdm_span_get_channel(span, i);
+
 			snprintf(tracepath, sizeof(tracepath), "%s-in-s%dc%d", argv[1], span_id, i);
-			ftdm_channel_command(chan, FTDM_COMMAND_TRACE_INPUT, tracepath);
+			status = ftdm_channel_command(chan, FTDM_COMMAND_TRACE_INPUT, tracepath);
+			if (status != FTDM_SUCCESS) {
+				stream->write_function(stream, "-ERR failed to enable input trace at path %s\n", tracepath);
+				goto end;
+			}
+
 			snprintf(tracepath, sizeof(tracepath), "%s-out-s%dc%d", argv[1], span_id, i);
-			ftdm_channel_command(chan, FTDM_COMMAND_TRACE_OUTPUT, tracepath);
+			status = ftdm_channel_command(chan, FTDM_COMMAND_TRACE_OUTPUT, tracepath);
+			if (status != FTDM_SUCCESS) {
+				stream->write_function(stream, "-ERR failed to enable output trace at path %s\n", tracepath);
+				ftdm_channel_command(chan, FTDM_COMMAND_TRACE_END_ALL, NULL);
+				goto end;
+			}
 		}
 	}
 	stream->write_function(stream, "+OK trace enabled with prefix path %s\n", argv[1]);

libs/freetdm/src/ftdm_io.c

@@ -728,7 +728,14 @@ static ftdm_status_t ftdm_span_destroy(ftdm_span_t *span)
 	}
 	ftdm_mutex_unlock(span->mutex);
 	ftdm_mutex_destroy(&span->mutex);
-	ftdm_safe_free(span->signal_data);
+
+	/* Give the span a chance to destroy its own signaling data */
+	if (span->destroy) {
+		span->destroy(span);
+	} else if (span->signal_data) {
+		/* We take care of their dirty business ... */
+		ftdm_free(span->signal_data);
+	}
 
 	return status;
 }
@@ -5520,7 +5527,8 @@ FT_DECLARE(ftdm_io_interface_t *) ftdm_global_get_io_interface(const char *iotyp
 FT_DECLARE(int) ftdm_load_module(const char *name)
 {
 	ftdm_dso_lib_t lib;
-	int count = 0, x = 0;
+	int count = 0;
+	ftdm_bool_t load_proceed = FTDM_TRUE;
 	char path[512] = "";
 	char *err;
 	ftdm_module_t *mod;
@@ -5544,11 +5552,11 @@ FT_DECLARE(int) ftdm_load_module(const char *name)
 
 		if (mod->io_load(&interface1) != FTDM_SUCCESS || !interface1 || !interface1->name) {
 			ftdm_log(FTDM_LOG_ERROR, "Error loading %s\n", path);
+			load_proceed = FTDM_FALSE;
 		} else {
 			ftdm_log(FTDM_LOG_INFO, "Loading IO from %s [%s]\n", path, interface1->name);
 			if (ftdm_global_add_io_interface(interface1) == FTDM_SUCCESS) {
 				process_module_config(interface1);
-				x++;
 			}
 		}
 	}
@@ -5556,13 +5564,13 @@ FT_DECLARE(int) ftdm_load_module(const char *name)
 	if (mod->sig_load) {
 		if (mod->sig_load() != FTDM_SUCCESS) {
 			ftdm_log(FTDM_LOG_ERROR, "Error loading %s\n", path);
+			load_proceed = FTDM_FALSE;
 		} else {
 			ftdm_log(FTDM_LOG_INFO, "Loading SIG from %s\n", path);
-			x++;
 		}
 	}
 
-	if (x) {
+	if (load_proceed) {
 		char *p;
 		mod->lib = lib;
 		ftdm_set_string(mod->path, path);
@@ -5583,7 +5591,7 @@ FT_DECLARE(int) ftdm_load_module(const char *name)
 		}
 		ftdm_mutex_unlock(globals.mutex);
 	} else {
-		ftdm_log(FTDM_LOG_ERROR, "Unloading %s\n", path);
+		ftdm_log(FTDM_LOG_ERROR, "Errors during module load. Unloading %s\n", path);
 		ftdm_dso_destroy(&lib);
 	}
 	

libs/freetdm/src/include/private/ftdm_core.h

@@ -512,6 +512,7 @@ struct ftdm_span {
 	fio_channel_request_t channel_request;
 	ftdm_span_start_t start;
 	ftdm_span_stop_t stop;
+	ftdm_span_destroy_t destroy;
 	ftdm_channel_sig_read_t sig_read;
 	ftdm_channel_sig_write_t sig_write;
 	ftdm_channel_sig_dtmf_t sig_queue_dtmf;

libs/freetdm/src/include/private/ftdm_types.h

@@ -348,6 +348,7 @@ typedef struct ftdm_bitstream ftdm_bitstream_t;
 typedef struct ftdm_fsk_modulator ftdm_fsk_modulator_t;
 typedef ftdm_status_t (*ftdm_span_start_t)(ftdm_span_t *span);
 typedef ftdm_status_t (*ftdm_span_stop_t)(ftdm_span_t *span);
+typedef ftdm_status_t (*ftdm_span_destroy_t)(ftdm_span_t *span);
 typedef ftdm_status_t (*ftdm_channel_sig_read_t)(ftdm_channel_t *ftdmchan, void *data, ftdm_size_t size);
 typedef ftdm_status_t (*ftdm_channel_sig_write_t)(ftdm_channel_t *ftdmchan, void *data, ftdm_size_t size);
 typedef ftdm_status_t (*ftdm_channel_sig_dtmf_t)(ftdm_channel_t *ftdmchan, const char *dtmf);