freetdm: Added new OOB event FTDM_OOB_POLARITY_REVERSE

Added new channel command FTDM_COMMAND_SET_POLARITY
         ftmod_wanpipe - Added support to enqueue polarity events on FXO lines
	 ftmod_wanpipe - Added support to set polarity on FXS lines
	 ftmod_analog - Added support to answer and hangup FXO lines on polarity reverse
	 ftmod_analog - Added support to reverse polarity in the FXS line on answer and hangup
	 mod_freetdm - Added parameters answer-on-polarity, hangup-on-polarity and polarity-delay
                       to enable those analog features

libs/freetdm/conf/freetdm.conf.xml

@@ -12,31 +12,81 @@ with the signaling protocols that you can run on top of your I/O interfaces.
 	<settings>
 		<param name="debug" value="0"/>
 		<!--<param name="hold-music" value="$${moh_uri}"/>-->
+		<!-- Analog global options (they apply to all spans) 
+		     Remember you can only choose between either call-swap
+		     or 3-way, not both!
+		-->
 		<!--<param name="enable-analog-option" value="call-swap"/>-->
 		<!--<param name="enable-analog-option" value="3-way"/>-->
 	</settings>
 
-	<!-- Sample analog configuration -->
+	<!-- Sample analog configuration (The analog_spans tag is for ftmod_analog) -->
 	<analog_spans>
 		<!-- The span name must match the name in your freetdm.conf -->
 		<span name="myAnalog">
 			<!--<param name="hold-music" value="$${moh_uri}"/>-->
-			<!--<param name="enable-analog-option" value="call-swap"/>-->
+			<!--
-			<!--<param name="enable-analog-option" value="3-way"/>-->
+			     3-way allows you to flash your FXS line and dial
+			     another number and put all the parties in a conference
+
+			     call-swap allows you to flash your FXS line and swap
+			     between one call and another
+
+			     Remember you can only choose between either call-swap
+			     or 3-way, not both!
+
+			<param name="enable-analog-option" value="call-swap"/>
+			<param name="enable-analog-option" value="3-way"/>
+			-->
+
+			<!-- Tones are defined in tones.conf
+			     This setting is very important for analog lines to
+			     work properly
+		       	-->
 			<param name="tonegroup" value="us"/>
+
+			<!-- How much time to wait for digits (in FXS lines) -->
 			<param name="digit-timeout" value="2000"/>
+
+			<!-- Maximum number of digits to wait for (in FXS lines) -->
 			<param name="max-digits" value="11"/>
-			<param name="dialplan" value="XML"/>
+
-			<param name="context" value="default"/>
+			<!-- whether you want to wait for caller id -->
 			<param name="enable-callerid" value="true"/>
+
+			<!-- whether you want to enable callwaiting feature -->
+			<!--<param name="callwaiting" value="true"/>-->
+
+			<!-- whether you want to answer/hangup on polarity reverse for outgoing calls in FXO devices 
+			     and send polarity reverse on answer/hangup for incoming calls in FXS devices -->
+			<!--<param name="answer-polarity-reverse" value="false"/>-->
+			<!--<param name="hangup-polarity-reverse" value="false"/>-->
+			<!--
+			Minimum delay (in milliseconds) required between an answer polarity reverse
+			and hangup polarity reverse in order to assume the second polarity reverse is a real hangup
+			<param name="polarity-delay" value="600"/>
+			-->
+
 			<!-- regex to stop dialing when it matches -->
 			<!--<param name="dial-regex" value="5555"/>-->
+
 			<!-- regex to stop dialing when it does not match -->
 			<!--<param name="fail-dial-regex" value="^5"/>-->
+
+			<!-- FreeSWITCH dialplan type and context to send the calls -->
+			<param name="dialplan" value="XML"/>
+			<param name="context" value="default"/>
 		</span>
 	</analog_spans>
 
-	<!-- openr2 (MFC-R2 signaling) spans 
+	<!-- 
+	
+ 	openr2 (MFC-R2 signaling) spans (ftmod_r2)
+	
+	In order to use this type of spans your FreeTDM must have been compiled with ftmod_r2 module.
+	The module is compiled if the openr2 library is present when running the ./configure script
+	in the FreeTDM source code
+
 	MFC-R2 signaling has lots of variants from country to country and even sometimes
 	minor variants inside the same country. The only mandatory parameters here are:
 	variant, but typically you also want to set max_ani and max_dnis.
@@ -46,6 +96,7 @@ with the signaling protocols that you can run on top of your I/O interfaces.
 	best defaults for your country.  If you want to contribute your configs for a particular 
 	country send them to the e-mail of the primary OpenR2 developer that you can find in the 
 	AUTHORS file of the OpenR2 package, they will be added to the samples directory of openr2.
+
 	-->
 	<r2_spans>
 		<span name="wp1" cfgprofile="testr2">

libs/freetdm/mod_freetdm/mod_freetdm.c

@@ -2717,6 +2717,9 @@ static switch_status_t load_config(void)
 			char *hold_music = NULL;
 			char *fail_dial_regex = NULL;
 			const char *enable_callerid = "true";
+			const char *answer_polarity = "false";
+			const char *hangup_polarity = "false";
+			int polarity_delay = 600;
 			int callwaiting = 1;
 
 			uint32_t span_id = 0, to = 0, max = 0;
@@ -2788,6 +2791,12 @@ static switch_status_t load_config(void)
 					dial_regex = val;
 				} else if (!strcasecmp(var, "enable-callerid")) {
 					enable_callerid = val;
+				} else if (!strcasecmp(var, "answer-polarity-reverse")) {
+					answer_polarity = val;
+				} else if (!strcasecmp(var, "hangup-polarity-reverse")) {
+					hangup_polarity = val;
+				} else if (!strcasecmp(var, "polarity-delay")) {
+					polarity_delay = atoi(val);
 				} else if (!strcasecmp(var, "fail-dial-regex")) {
 					fail_dial_regex = val;
 				} else if (!strcasecmp(var, "hold-music")) {
@@ -2848,6 +2857,9 @@ static switch_status_t load_config(void)
 								   "max_dialstr", &max,
 								   "hotline", hotline ? hotline : "",
 								   "enable_callerid", enable_callerid,
+								   "answer_polarity_reverse", answer_polarity,
+								   "hangup_polarity_reverse", hangup_polarity,
+								   "polarity_delay", &polarity_delay,
 								   "callwaiting", &callwaiting,
 								   FTDM_TAG_END) != FTDM_SUCCESS) {
 				ftdm_log(FTDM_LOG_ERROR, "Error configuring FreeTDM analog span %s\n", ftdm_span_get_name(span));

libs/freetdm/src/ftdm_io.c

@@ -1541,6 +1541,7 @@ end:
 		ftdm_mutex_unlock(ftdmchan->span->mutex);
 	} else {
 		ftdm_log_chan_ex(ftdmchan, file, func, line, FTDM_LOG_LEVEL_WARNING, "VETO state change from %s to %s\n", ftdm_channel_state2str(ftdmchan->state), ftdm_channel_state2str(state));
+		goto done;
 	}
 
 	/* there is an inherent race here between set and check of the change flag but we do not care because
@@ -1570,7 +1571,7 @@ end:
 		ftdm_log_chan_ex(ftdmchan, file, func, line, FTDM_LOG_LEVEL_WARNING, "state change from %s to %s was most likely not processed after aprox %dms\n",
 				ftdm_channel_state2str(ftdmchan->last_state), ftdm_channel_state2str(state), DEFAULT_WAIT_TIME);
 	}
-
+done:
 	return ok ? FTDM_SUCCESS : FTDM_FAIL;
 }
 
@@ -2289,8 +2290,15 @@ static ftdm_status_t call_hangup(ftdm_channel_t *chan, const char *file, const c
 		ftdm_channel_set_state(file, func, line, chan, FTDM_CHANNEL_STATE_HANGUP, 1);
 	} else {
 		/* the signaling stack did not touch the state, 
-		 * core is responsible from clearing flags and stuff */
+		 * core is responsible from clearing flags and stuff, however, because ftmod_analog
-		ftdm_channel_close(&chan);
+		 * is a bitch in a serious need of refactoring, we also check whether the channel is open
+		 * to avoid an spurious warning about the channel not being open. This is because ftmod_analog
+		 * does not follow our convention of sending SIGEVENT_STOP and waiting for the user to move
+		 * to HANGUP (implicitly through ftdm_channel_call_hangup(), as soon as ftmod_analog is fixed
+		 * this check can be removed */
+		if (ftdm_test_flag(chan, FTDM_CHANNEL_OPEN)) {
+			ftdm_channel_close(&chan);
+		}
 	}
 	return FTDM_SUCCESS;
 }
@@ -3933,7 +3941,7 @@ FT_DECLARE(ftdm_status_t) ftdm_channel_write(ftdm_channel_t *ftdmchan, void *dat
 
 
 	if (!ftdm_test_flag(ftdmchan, FTDM_CHANNEL_OPEN)) {
-		ftdm_log_chan_msg(ftdmchan, FTDM_LOG_ERROR, "cannot write in channel not open\n");
+		ftdm_log_chan_msg(ftdmchan, FTDM_LOG_WARNING, "cannot write in channel not open\n");
 		snprintf(ftdmchan->last_error, sizeof(ftdmchan->last_error), "channel not open");
 		status = FTDM_FAIL;
 		goto done;

libs/freetdm/src/ftmod/ftmod_analog/ftdm_analog.h

@@ -37,7 +37,9 @@
 
 typedef enum {
 	FTDM_ANALOG_RUNNING = (1 << 0),
-	FTDM_ANALOG_CALLERID = (1 << 1)
+	FTDM_ANALOG_CALLERID = (1 << 1),
+	FTDM_ANALOG_ANSWER_POLARITY_REVERSE = (1 << 2),
+	FTDM_ANALOG_HANGUP_POLARITY_REVERSE = (1 << 3)
 } ftdm_analog_flag_t;
 
 #define FTDM_MAX_HOTLINE_STR		20
@@ -47,11 +49,13 @@ struct ftdm_analog_data {
 	uint32_t flags;
 	uint32_t max_dialstr;
 	uint32_t wait_dialtone_timeout;
+	uint32_t polarity_delay;
 	uint32_t digit_timeout;
 	char hotline[FTDM_MAX_HOTLINE_STR];
 };
 
-
+/* Analog flags to be set in the sflags (signaling flags) channel memeber */
+#define AF_POLARITY_REVERSE (1 << 0)
 
 static void *ftdm_analog_run(ftdm_thread_t *me, void *obj);
 typedef struct ftdm_analog_data ftdm_analog_data_t;

libs/freetdm/src/ftmod/ftmod_analog/ftmod_analog.c

@@ -184,6 +184,7 @@ static FIO_SIG_CONFIGURE_FUNCTION(ftdm_analog_configure_span)
 	uint32_t digit_timeout = 10;
 	uint32_t wait_dialtone_timeout = 30000;
 	uint32_t max_dialstr = MAX_DTMF;
+	uint32_t polarity_delay = 600;
 	const char *var, *val;
 	int *intval;
 	uint32_t flags = FTDM_ANALOG_CALLERID;
@@ -236,6 +237,29 @@ static FIO_SIG_CONFIGURE_FUNCTION(ftdm_analog_configure_span)
 			} else {
 				flags &= ~FTDM_ANALOG_CALLERID;
 			}
+		} else if (!strcasecmp(var, "answer_polarity_reverse")) {
+			if (!(val = va_arg(ap, char *))) {
+                		break;
+            		}
+			if (ftdm_true(val)) {
+				flags |= FTDM_ANALOG_ANSWER_POLARITY_REVERSE;
+			} else {
+				flags &= ~FTDM_ANALOG_ANSWER_POLARITY_REVERSE;
+			}
+		} else if (!strcasecmp(var, "hangup_polarity_reverse")) {
+			if (!(val = va_arg(ap, char *))) {
+                		break;
+            		}
+			if (ftdm_true(val)) {
+				flags |= FTDM_ANALOG_HANGUP_POLARITY_REVERSE;
+			} else {
+				flags &= ~FTDM_ANALOG_HANGUP_POLARITY_REVERSE;
+			}
+		} else if (!strcasecmp(var, "polarity_delay")) {
+			if (!(intval = va_arg(ap, int *))) {
+                		break;
+            		}
+			polarity_delay = *intval;
 		} else if (!strcasecmp(var, "callwaiting")) {
 			if (!(intval = va_arg(ap, int *))) {
                 		break;
@@ -276,6 +300,7 @@ static FIO_SIG_CONFIGURE_FUNCTION(ftdm_analog_configure_span)
 	analog_data->flags = flags;
 	analog_data->digit_timeout = digit_timeout;
 	analog_data->wait_dialtone_timeout = wait_dialtone_timeout;
+	analog_data->polarity_delay = polarity_delay;
 	analog_data->max_dialstr = max_dialstr;
 	span->signal_cb = sig_cb;
 	strncpy(analog_data->hotline, hotline, sizeof(analog_data->hotline));
@@ -399,6 +424,7 @@ static void *ftdm_analog_channel_run(ftdm_thread_t *me, void *obj)
 	ftdm_analog_data_t *analog_data = ftdmchan->span->signal_data;
 	ftdm_channel_t *closed_chan;
 	uint32_t state_counter = 0, elapsed = 0, collecting = 0, interval = 0, last_digit = 0, indicate = 0, dial_timeout = analog_data->wait_dialtone_timeout;
+	uint32_t answer_on_polarity_counter = 0;
 	ftdm_sigmsg_t sig;
 	ftdm_status_t status;
 	
@@ -470,7 +496,12 @@ static void *ftdm_analog_channel_run(ftdm_thread_t *me, void *obj)
 						if (ftdmchan->needed_tones[FTDM_TONEMAP_DIAL]) {
 							ftdm_set_state_locked(ftdmchan, FTDM_CHANNEL_STATE_BUSY);
 						} else {
-							ftdm_set_state_locked(ftdmchan, FTDM_CHANNEL_STATE_UP);
+							/* do not go up if we're waiting for polarity reversal */
+							if (ftdm_test_flag(analog_data, FTDM_ANALOG_ANSWER_POLARITY_REVERSE)) {
+								ftdm_set_state_locked(ftdmchan, FTDM_CHANNEL_STATE_PROGRESS_MEDIA);
+							} else {
+								ftdm_set_state_locked(ftdmchan, FTDM_CHANNEL_STATE_UP);
+							}
 						}
 					}
 				}
@@ -561,8 +592,30 @@ static void *ftdm_analog_channel_run(ftdm_thread_t *me, void *obj)
 				}
 			case FTDM_CHANNEL_STATE_UP:
 			case FTDM_CHANNEL_STATE_RING:
+			case FTDM_CHANNEL_STATE_PROGRESS_MEDIA:
 				{
-					ftdm_sleep(interval);
+					if (ftdm_test_flag(ftdmchan, FTDM_CHANNEL_OUTBOUND) &&
+					    ftdmchan->state == FTDM_CHANNEL_STATE_PROGRESS_MEDIA && 
+					    ftdm_test_sflag(ftdmchan, AF_POLARITY_REVERSE)) {
+						ftdm_log_chan_msg(ftdmchan, FTDM_LOG_NOTICE, "Answering on polarity reverse\n");
+						ftdm_clear_sflag(ftdmchan, AF_POLARITY_REVERSE);
+						ftdm_set_state_locked(ftdmchan, FTDM_CHANNEL_STATE_UP);
+						answer_on_polarity_counter = state_counter;
+					} else if (ftdmchan->state == FTDM_CHANNEL_STATE_UP
+						   && ftdm_test_sflag(ftdmchan, AF_POLARITY_REVERSE)){
+						/* if this polarity reverse is close to the answer polarity reverse, ignore it */
+						if (answer_on_polarity_counter 
+						&& (state_counter - answer_on_polarity_counter) > analog_data->polarity_delay) {
+							ftdm_log_chan_msg(ftdmchan, FTDM_LOG_NOTICE, "Hanging up on polarity reverse\n");
+							ftdm_set_state_locked(ftdmchan, FTDM_CHANNEL_STATE_HANGUP);
+						} else {
+							ftdm_log_chan_msg(ftdmchan, FTDM_LOG_WARNING, 
+							"Not hanging up on polarity reverse, too close to Answer reverse\n");
+						}
+						ftdm_clear_sflag(ftdmchan, AF_POLARITY_REVERSE);
+					} else {
+						ftdm_sleep(interval);
+					}
 					continue;
 				}
 				break;
@@ -615,6 +668,18 @@ static void *ftdm_analog_channel_run(ftdm_thread_t *me, void *obj)
 						sig.event_id = FTDM_SIGEVENT_UP;
 					}
 
+					if (ftdmchan->type == FTDM_CHAN_TYPE_FXS &&
+					    !ftdm_test_flag(ftdmchan, FTDM_CHANNEL_OUTBOUND) &&
+					    ftdm_test_flag(analog_data, FTDM_ANALOG_ANSWER_POLARITY_REVERSE)) {
+						ftdm_polarity_t polarity = FTDM_POLARITY_REVERSE;
+						if (ftdmchan->polarity != FTDM_POLARITY_FORWARD) {
+							ftdm_log_chan_msg(ftdmchan, FTDM_LOG_ERROR, "Polarity is already reversed on answer??\n");
+						} else {
+							ftdm_log_chan_msg(ftdmchan, FTDM_LOG_DEBUG, "Reversing polarity on answer\n");
+							ftdm_channel_command(ftdmchan, FTDM_COMMAND_SET_POLARITY, &polarity);
+						}
+					}
+
 					ftdm_span_send_signal(ftdmchan->span, &sig);
 					continue;
 				}
@@ -639,6 +704,22 @@ static void *ftdm_analog_channel_run(ftdm_thread_t *me, void *obj)
 					continue;
 				}
 				break;
+
+			case FTDM_CHANNEL_STATE_HANGUP:
+				/* this state is only used when the user hangup, if the device hang up (onhook) we currently
+				 * go straight to DOWN. If we ever change this (as other signaling modules do) by using this
+				 * state for both user and device hangup, we should check here for the type of hangup since
+				 * some actions (polarity reverse) do not make sense if the device hung up */
+				if (ftdmchan->type == FTDM_CHAN_TYPE_FXS &&
+				    ftdmchan->last_state == FTDM_CHANNEL_STATE_UP &&
+				    ftdm_test_flag(analog_data, FTDM_ANALOG_HANGUP_POLARITY_REVERSE)) {
+					ftdm_polarity_t polarity = ftdmchan->polarity == FTDM_POLARITY_REVERSE 
+						                 ? FTDM_POLARITY_FORWARD : FTDM_POLARITY_REVERSE;
+					ftdm_log_chan_msg(ftdmchan, FTDM_LOG_DEBUG, "Reversing polarity on hangup\n");
+					ftdm_channel_command(ftdmchan, FTDM_COMMAND_SET_POLARITY, &polarity);
+				}
+				break;
+
 			case FTDM_CHANNEL_STATE_DOWN:
 				{
 					sig.event_id = FTDM_SIGEVENT_STOP;
@@ -847,6 +928,9 @@ static void *ftdm_analog_channel_run(ftdm_thread_t *me, void *obj)
 
  done:
 
+	closed_chan = ftdmchan;
+
+	ftdm_channel_lock(closed_chan);
 
 	if (ftdmchan->type == FTDM_CHAN_TYPE_FXO && ftdm_test_flag(ftdmchan, FTDM_CHANNEL_OFFHOOK)) {
 		ftdm_channel_command(ftdmchan, FTDM_COMMAND_ONHOOK, NULL);
@@ -857,7 +941,8 @@ static void *ftdm_analog_channel_run(ftdm_thread_t *me, void *obj)
 	}
 
 	
-	closed_chan = ftdmchan;
+	ftdm_clear_sflag(ftdmchan, AF_POLARITY_REVERSE);
+
 	ftdm_channel_close(&ftdmchan);
 
 	ftdm_channel_command(closed_chan, FTDM_COMMAND_SET_NATIVE_CODEC, NULL);
@@ -875,8 +960,11 @@ static void *ftdm_analog_channel_run(ftdm_thread_t *me, void *obj)
 	}
 
 	ftdm_log_chan(closed_chan, FTDM_LOG_DEBUG, "ANALOG CHANNEL %d:%d thread ended.\n", closed_chan->span_id, closed_chan->chan_id);
+
 	ftdm_clear_flag(closed_chan, FTDM_CHANNEL_INTHREAD);
 
+	ftdm_channel_unlock(closed_chan);
+
 	return NULL;
 }
 
@@ -903,6 +991,19 @@ static __inline__ ftdm_status_t process_event(ftdm_span_t *span, ftdm_event_t *e
 	ftdm_mutex_lock(event->channel->mutex);
 	locked++;
 
+	/* MAINTENANCE WARNING: 
+	 * 1. Be aware you are working on the locked channel
+	 * 2. We should not be calling ftdm_span_send_signal or ftdm_set_state when there is already a channel thread running
+	 *    however, since this is old code I am not changing it now, but new code should adhere to that convention
+	 *    otherwise, we have possible races where we compete with the user for state changes, ie, the user requests
+	 *    a state change and then we process an event, the state change from the user is pending so our ftdm_set_state
+	 *    operation will fail. In cases where we win the race, our state change will be accepted but if a user requests
+	 *    a state change before the state change we requested here is processed by the channel thread, we'll end up
+	 *    rejecting the user request.
+	 *
+	 *    See docs/locking.txt for further information about what guarantees should signaling modules provide when
+	 *    locking/unlocking a channel
+	 * */
 	switch(event->enum_id) {
 	case FTDM_OOB_RING_START:
 		{
@@ -940,7 +1041,11 @@ static __inline__ ftdm_status_t process_event(ftdm_span_t *span, ftdm_event_t *e
 				}
 				ftdm_set_state(event->channel, FTDM_CHANNEL_STATE_DOWN);
 			}
-
+			if (event->channel->type == FTDM_CHAN_TYPE_FXS) {
+				/* we always return to forward when the device goes onhook */
+				ftdm_polarity_t forward_polarity = FTDM_POLARITY_FORWARD;
+				ftdm_channel_command(event->channel, FTDM_COMMAND_SET_POLARITY, &forward_polarity);
+			}
 		}
 		break;
 	case FTDM_OOB_FLASH:
@@ -1004,6 +1109,35 @@ static __inline__ ftdm_status_t process_event(ftdm_span_t *span, ftdm_event_t *e
 			ftdm_span_send_signal(span, &sig);
 		}
 		break;
+	case FTDM_OOB_POLARITY_REVERSE:
+		{
+			if (event->channel->type != FTDM_CHAN_TYPE_FXO) {
+				ftdm_log_chan_msg(event->channel, FTDM_LOG_WARNING, 
+						"Ignoring polarity reversal, this should not happen in non-FXO channels!\n");
+				break;
+			}
+			if (!ftdm_test_flag(event->channel, FTDM_CHANNEL_INTHREAD) &&
+			     ftdm_test_flag(event->channel, FTDM_CHANNEL_OFFHOOK)) {
+				ftdm_log_chan_msg(event->channel, FTDM_LOG_WARNING, 
+					"Forcing onhook in channel not in thread after polarity reversal\n");
+				ftdm_channel_command(event->channel, FTDM_COMMAND_ONHOOK, NULL);
+				break;
+			}
+			if (!ftdm_test_flag(analog_data, FTDM_ANALOG_ANSWER_POLARITY_REVERSE) 
+			 && !ftdm_test_flag(analog_data, FTDM_ANALOG_HANGUP_POLARITY_REVERSE)) {
+				ftdm_log_chan_msg(event->channel, FTDM_LOG_DEBUG, 
+					"Ignoring polarity reversal because this channel is not configured for it\n");
+				break;
+			}
+			if (event->channel->state == FTDM_CHANNEL_STATE_DOWN) {
+				ftdm_log_chan_msg(event->channel, FTDM_LOG_DEBUG, 
+					"Ignoring polarity reversal because this channel is down\n");
+				break;
+			}
+			/* we have a good channel, set the polarity flag and let the channel thread deal with it */
+			ftdm_set_sflag(event->channel, AF_POLARITY_REVERSE);
+		}
+		break;
 	default:
 		{
 			ftdm_log_chan(event->channel, FTDM_LOG_DEBUG, "Ignoring event [%s] in state [%s]\n", ftdm_oob_event2str(event->enum_id), ftdm_channel_state2str(event->channel->state));

libs/freetdm/src/ftmod/ftmod_wanpipe/ftmod_wanpipe.c

@@ -784,17 +784,27 @@ static FIO_COMMAND_FUNCTION(wanpipe_command)
 			err = sangoma_set_tx_queue_sz(ftdmchan->sockfd, &tdm_api, queue_size);
 		}
 		break;
+	case FTDM_COMMAND_SET_POLARITY:
+		{
+			ftdm_polarity_t polarity = FTDM_COMMAND_OBJ_INT;
+			err = sangoma_tdm_set_polarity(ftdmchan->sockfd, &tdm_api, polarity);
+			if (!err) {
+				ftdmchan->polarity = polarity;
+			}
+		}
+		break;
 	default:
 		err = FTDM_NOTIMPL;
 		break;
 	};
 
 	if (err) {
-		snprintf(ftdmchan->last_error, sizeof(ftdmchan->last_error), "%s", strerror(errno));
+		int myerrno = errno;
+		ftdm_log_chan(ftdmchan, FTDM_LOG_ERROR, "Wanpipe failed to execute command %d: %s\n", command, strerror(myerrno));
+		errno = myerrno;
 		return err;
 	}
 
-
 	return FTDM_SUCCESS;
 }
 
@@ -1237,8 +1247,9 @@ FIO_CHANNEL_NEXT_EVENT_FUNCTION(wanpipe_channel_next_event)
 	wanpipe_tdm_api_t tdm_api;
 	ftdm_span_t *span = ftdmchan->span;
 
-	if (ftdm_test_flag(ftdmchan, FTDM_CHANNEL_EVENT))
+	if (ftdm_test_flag(ftdmchan, FTDM_CHANNEL_EVENT)) {
 		ftdm_clear_flag(ftdmchan, FTDM_CHANNEL_EVENT);
+	}
 
 	memset(&tdm_api, 0, sizeof(tdm_api));
 	status = sangoma_tdm_read_event(ftdmchan->sockfd, &tdm_api);
@@ -1251,7 +1262,7 @@ FIO_CHANNEL_NEXT_EVENT_FUNCTION(wanpipe_channel_next_event)
 	ftdm_log_chan(ftdmchan, FTDM_LOG_DEBUG, "read wanpipe event %d\n", tdm_api.wp_tdm_cmd.event.wp_tdm_api_event_type);
 	switch(tdm_api.wp_tdm_cmd.event.wp_tdm_api_event_type) {
 
-	case WP_TDMAPI_EVENT_LINK_STATUS:
+	case WP_API_EVENT_LINK_STATUS:
 		{
 			switch(tdm_api.wp_tdm_cmd.event.wp_tdm_api_event_link_status) {
 			case WP_TDMAPI_EVENT_LINK_STATUS_CONNECTED:
@@ -1264,7 +1275,7 @@ FIO_CHANNEL_NEXT_EVENT_FUNCTION(wanpipe_channel_next_event)
 		}
 		break;
 
-	case WP_TDMAPI_EVENT_RXHOOK:
+	case WP_API_EVENT_RXHOOK:
 		{
 			if (ftdmchan->type == FTDM_CHAN_TYPE_FXS) {
 				event_id = tdm_api.wp_tdm_cmd.event.wp_tdm_api_event_hook_state & WP_TDMAPI_EVENT_RXHOOK_OFF ? FTDM_OOB_OFFHOOK : FTDM_OOB_ONHOOK;
@@ -1300,26 +1311,26 @@ FIO_CHANNEL_NEXT_EVENT_FUNCTION(wanpipe_channel_next_event)
 			}
 		}
 		break;
-	case WP_TDMAPI_EVENT_RING_DETECT:
+	case WP_API_EVENT_RING_DETECT:
 		{
 			event_id = tdm_api.wp_tdm_cmd.event.wp_tdm_api_event_ring_state == WP_TDMAPI_EVENT_RING_PRESENT ? FTDM_OOB_RING_START : FTDM_OOB_RING_STOP;
 		}
 		break;
 		/*
 		disabled this ones when configuring, we don't need them, do we?
-	case WP_TDMAPI_EVENT_RING_TRIP_DETECT:
+	case WP_API_EVENT_RING_TRIP_DETECT:
 		{
 			event_id = tdm_api.wp_tdm_cmd.event.wp_tdm_api_event_ring_state == WP_TDMAPI_EVENT_RING_PRESENT ? FTDM_OOB_ONHOOK : FTDM_OOB_OFFHOOK;
 		}
 		break;
 		*/
-	case WP_TDMAPI_EVENT_RBS:
+	case WP_API_EVENT_RBS:
 		{
 			event_id = FTDM_OOB_CAS_BITS_CHANGE;
 			ftdmchan->rx_cas_bits = wanpipe_swap_bits(tdm_api.wp_tdm_cmd.event.wp_tdm_api_event_rbs_bits);
 		}
 		break;
-	case WP_TDMAPI_EVENT_DTMF:
+	case WP_API_EVENT_DTMF:
 		{
 			char tmp_dtmf[2] = { tdm_api.wp_tdm_cmd.event.wp_tdm_api_event_dtmf_digit, 0 };
 			event_id = FTDM_OOB_NOOP;
@@ -1342,12 +1353,18 @@ FIO_CHANNEL_NEXT_EVENT_FUNCTION(wanpipe_channel_next_event)
 			} 
 		}
 		break;
-	case WP_TDMAPI_EVENT_ALARM:
+	case WP_API_EVENT_ALARM:
 		{
 			ftdm_log_chan(ftdmchan, FTDM_LOG_DEBUG, "Got wanpipe alarms %d\n", tdm_api.wp_tdm_cmd.event.wp_api_event_alarm);
 			event_id = FTDM_OOB_ALARM_TRAP;
 		}
 		break;
+	case WP_API_EVENT_POLARITY_REVERSE:
+		{
+			ftdm_log_chan_msg(ftdmchan, FTDM_LOG_DEBUG, "Got polarity reverse\n");
+			event_id = FTDM_OOB_POLARITY_REVERSE;
+		}
+		break;
 	default:
 		{
 			ftdm_log_chan(ftdmchan, FTDM_LOG_WARNING, "Unhandled wanpipe event %d\n", tdm_api.wp_tdm_cmd.event.wp_tdm_api_event_type);
@@ -1423,7 +1440,7 @@ FIO_SPAN_NEXT_EVENT_FUNCTION(wanpipe_span_next_event)
 			ftdm_log_chan(span->channels[i], FTDM_LOG_DEBUG, "read wanpipe event %d\n", tdm_api.wp_tdm_cmd.event.wp_tdm_api_event_type);
 			switch(tdm_api.wp_tdm_cmd.event.wp_tdm_api_event_type) {
 
-			case WP_TDMAPI_EVENT_LINK_STATUS:
+			case WP_API_EVENT_LINK_STATUS:
 				{
 					switch(tdm_api.wp_tdm_cmd.event.wp_tdm_api_event_link_status) {
 					case WP_TDMAPI_EVENT_LINK_STATUS_CONNECTED:
@@ -1436,7 +1453,7 @@ FIO_SPAN_NEXT_EVENT_FUNCTION(wanpipe_span_next_event)
 				}
 				break;
 
-			case WP_TDMAPI_EVENT_RXHOOK:
+			case WP_API_EVENT_RXHOOK:
 				{
 					if (span->channels[i]->type == FTDM_CHAN_TYPE_FXS) {
 						event_id = tdm_api.wp_tdm_cmd.event.wp_tdm_api_event_hook_state & WP_TDMAPI_EVENT_RXHOOK_OFF ? FTDM_OOB_OFFHOOK : FTDM_OOB_ONHOOK;
@@ -1472,26 +1489,26 @@ FIO_SPAN_NEXT_EVENT_FUNCTION(wanpipe_span_next_event)
 					}
 				}
 				break;
-			case WP_TDMAPI_EVENT_RING_DETECT:
+			case WP_API_EVENT_RING_DETECT:
 				{
 					event_id = tdm_api.wp_tdm_cmd.event.wp_tdm_api_event_ring_state == WP_TDMAPI_EVENT_RING_PRESENT ? FTDM_OOB_RING_START : FTDM_OOB_RING_STOP;
 				}
 				break;
 				/*
 				disabled this ones when configuring, we don't need them, do we?
-			case WP_TDMAPI_EVENT_RING_TRIP_DETECT:
+			case WP_API_EVENT_RING_TRIP_DETECT:
 				{
 					event_id = tdm_api.wp_tdm_cmd.event.wp_tdm_api_event_ring_state == WP_TDMAPI_EVENT_RING_PRESENT ? FTDM_OOB_ONHOOK : FTDM_OOB_OFFHOOK;
 				}
 				break;
 				*/
-			case WP_TDMAPI_EVENT_RBS:
+			case WP_API_EVENT_RBS:
 				{
 					event_id = FTDM_OOB_CAS_BITS_CHANGE;
 					span->channels[i]->rx_cas_bits = wanpipe_swap_bits(tdm_api.wp_tdm_cmd.event.wp_tdm_api_event_rbs_bits);
 				}
 				break;
-			case WP_TDMAPI_EVENT_DTMF:
+			case WP_API_EVENT_DTMF:
 				{
 					char tmp_dtmf[2] = { tdm_api.wp_tdm_cmd.event.wp_tdm_api_event_dtmf_digit, 0 };
 					event_id = FTDM_OOB_NOOP;
@@ -1514,12 +1531,18 @@ FIO_SPAN_NEXT_EVENT_FUNCTION(wanpipe_span_next_event)
 					} 
 				}
 				break;
-			case WP_TDMAPI_EVENT_ALARM:
+			case WP_API_EVENT_ALARM:
 				{
 					ftdm_log_chan(ftdmchan, FTDM_LOG_DEBUG, "Got wanpipe alarms %d\n", tdm_api.wp_tdm_cmd.event.wp_api_event_alarm);
 					event_id = FTDM_OOB_ALARM_TRAP;
 				}
 				break;
+			case WP_API_EVENT_POLARITY_REVERSE:
+				{
+					ftdm_log_chan_msg(ftdmchan, FTDM_LOG_DEBUG, "Got polarity reverse\n");
+					event_id = FTDM_OOB_POLARITY_REVERSE;
+				}
+				break;
 			default:
 				{
 					ftdm_log_chan(ftdmchan, FTDM_LOG_WARNING, "Unhandled wanpipe event %d\n", tdm_api.wp_tdm_cmd.event.wp_tdm_api_event_type);

libs/freetdm/src/include/freetdm.h

@@ -557,8 +557,14 @@ typedef enum {
 	FTDM_COMMAND_COUNT,
 	FTDM_COMMAND_SET_RX_QUEUE_SIZE,
 	FTDM_COMMAND_SET_TX_QUEUE_SIZE,
+	FTDM_COMMAND_SET_POLARITY,
 } ftdm_command_t;
 
+typedef enum {
+	FTDM_POLARITY_FORWARD = 0,
+	FTDM_POLARITY_REVERSE = 1
+} ftdm_polarity_t;
+
 /*! \brief Custom memory handler hooks. Not recommended to use unless you need memory allocation customizations */
 typedef void *(*ftdm_malloc_func_t)(void *pool, ftdm_size_t len);
 typedef void *(*ftdm_calloc_func_t)(void *pool, ftdm_size_t elements, ftdm_size_t len);

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

@@ -143,7 +143,9 @@ extern "C" {
   \return true value if the object has the flags defined
 */
 #define ftdm_test_flag(obj, flag) ((obj)->flags & flag)
+/*!< Physical (IO) module specific flags */
 #define ftdm_test_pflag(obj, flag) ((obj)->pflags & flag)
+/*!< signaling module specific flags */
 #define ftdm_test_sflag(obj, flag) ((obj)->sflags & flag)
 
 #define ftdm_set_alarm_flag(obj, flag) (obj)->alarm_flags |= (flag)
@@ -456,6 +458,7 @@ struct ftdm_channel {
 	ftdm_fsk_data_state_t fsk;
 	uint8_t fsk_buf[80];
 	uint32_t ring_count;
+	ftdm_polarity_t polarity;
 	/* Private I/O data. Do not touch unless you are an I/O module */
 	void *io_data;
 	/* Private signaling data. Do not touch unless you are a signaling module */

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

@@ -123,6 +123,7 @@ typedef enum {
 FTDM_STR2ENUM_P(ftdm_str2ftdm_analog_start_type, ftdm_analog_start_type2str, ftdm_analog_start_type_t)
 
 typedef enum {
+	FTDM_OOB_NOOP,
 	FTDM_OOB_ONHOOK,
 	FTDM_OOB_OFFHOOK,
 	FTDM_OOB_WINK,
@@ -131,11 +132,11 @@ typedef enum {
 	FTDM_OOB_RING_STOP,
 	FTDM_OOB_ALARM_TRAP,
 	FTDM_OOB_ALARM_CLEAR,
-	FTDM_OOB_NOOP,
 	FTDM_OOB_CAS_BITS_CHANGE,
+	FTDM_OOB_POLARITY_REVERSE,
 	FTDM_OOB_INVALID
 } ftdm_oob_event_t;
-#define OOB_STRINGS "ONHOOK", "OFFHOOK", "WINK", "FLASH", "RING_START", "RING_STOP", "ALARM_TRAP", "ALARM_CLEAR", "NOOP", "CAS_BITS_CHANGE", "INVALID"
+#define OOB_STRINGS "NOOP", "ONHOOK", "OFFHOOK", "WINK", "FLASH", "RING_START", "RING_STOP", "ALARM_TRAP", "ALARM_CLEAR", "CAS_BITS_CHANGE", "POLARITY_REVERSE", "INVALID"
 FTDM_STR2ENUM_P(ftdm_str2ftdm_oob_event, ftdm_oob_event2str, ftdm_oob_event_t)
 
 /*! \brief Event types */