From aa69927b8fec99064da113bd6181dd38e82e0d46 Mon Sep 17 00:00:00 2001
From: Moises Silva <moy@sangoma.com>
Date: Fri, 17 Dec 2010 20:04:30 -0500
Subject: [PATCH] freetdm: OPENZAP-124 - Add round robin hunting direction
 (Patched by Ric)

---
 libs/freetdm/mod_freetdm/mod_freetdm.c       |  4 ++
 libs/freetdm/src/ftdm_io.c                   | 41 +++++++++++++++++++-
 libs/freetdm/src/include/freetdm.h           |  4 +-
 libs/freetdm/src/include/private/ftdm_core.h |  1 +
 4 files changed, 48 insertions(+), 2 deletions(-)

diff --git a/libs/freetdm/mod_freetdm/mod_freetdm.c b/libs/freetdm/mod_freetdm/mod_freetdm.c
index 0615b3821b..7637932b79 100755
--- a/libs/freetdm/mod_freetdm/mod_freetdm.c
+++ b/libs/freetdm/mod_freetdm/mod_freetdm.c
@@ -1136,6 +1136,10 @@ static switch_call_cause_t channel_outgoing_channel(switch_core_session_t *sessi
 		direction = FTDM_BOTTOM_UP;
 	} else if (*argv[1] == 'a') {
 		direction =  FTDM_TOP_DOWN;
+	} else if (*argv[1] == 'r') {
+		direction =  FTDM_RR_DOWN;
+	} else if (*argv[1] == 'R') {
+		direction =  FTDM_RR_UP;
 	} else {
 		chan_id = atoi(argv[1]);
 	}
diff --git a/libs/freetdm/src/ftdm_io.c b/libs/freetdm/src/ftdm_io.c
index 36b7632cb3..94a01aa7ba 100644
--- a/libs/freetdm/src/ftdm_io.c
+++ b/libs/freetdm/src/ftdm_io.c
@@ -1706,6 +1706,21 @@ static ftdm_status_t __inline__ get_best_rated(ftdm_channel_t **fchan, ftdm_chan
 	return FTDM_SUCCESS;
 }
 
+static uint32_t __inline__ rr_next(uint32_t last, uint32_t min, uint32_t max, ftdm_direction_t direction)
+{
+	uint32_t next = min;
+
+	ftdm_log(FTDM_LOG_DEBUG, "last = %d, min = %d, max = %d\n", last, min, max);
+
+	if (direction == FTDM_RR_DOWN) {
+		next = (last >= max) ? min : ++last;
+	} else {
+		next = (last <= min) ? max : --last;
+	}
+	return next;
+}
+
+
 FT_DECLARE(int) ftdm_channel_get_availability(ftdm_channel_t *ftdmchan)
 {
 	int availability = -1;
@@ -1748,6 +1763,8 @@ FT_DECLARE(ftdm_status_t) ftdm_channel_open_by_group(uint32_t group_id, ftdm_dir
 	
 	if (direction == FTDM_TOP_DOWN) {
 		i = 0;
+	} else if (direction == FTDM_RR_DOWN || direction == FTDM_RR_UP) {
+		i = rr_next(group->last_used_index, 0, group->chan_count - 1, direction);
 	} else {
 		i = group->chan_count-1;
 	}
@@ -1762,16 +1779,24 @@ FT_DECLARE(ftdm_status_t) ftdm_channel_open_by_group(uint32_t group_id, ftdm_dir
 
 		if (request_voice_channel(check, ftdmchan, caller_data, direction)) {
 			status = FTDM_SUCCESS;
+			if (direction == FTDM_RR_UP || direction == FTDM_RR_DOWN) {
+				group->last_used_index = i;
+			}
 			break;
 		}
 
 		calculate_best_rate(check, &best_rated, &best_rate);
 
 		if (direction == FTDM_TOP_DOWN) {
-			if (i >= group->chan_count) {
+			if (i >= (group->chan_count - 1)) {
 				break;
 			}
 			i++;
+		} else if (direction == FTDM_RR_DOWN || direction == FTDM_RR_UP) {
+			if (check == best_rated) {
+				group->last_used_index = i;
+			}
+			i = rr_next(i, 0, group->chan_count - 1, direction);
 		} else {
 			if (i == 0) {
 				break;
@@ -1850,6 +1875,8 @@ FT_DECLARE(ftdm_status_t) ftdm_channel_open_by_span(uint32_t span_id, ftdm_direc
 	
 	if (direction == FTDM_TOP_DOWN) {
 		i = 1;
+	} else if (direction == FTDM_RR_DOWN || direction == FTDM_RR_UP) {
+		i = rr_next(span->last_used_index, 1, span->chan_count, direction);
 	} else {
 		i = span->chan_count;
 	}	
@@ -1860,6 +1887,10 @@ FT_DECLARE(ftdm_status_t) ftdm_channel_open_by_span(uint32_t span_id, ftdm_direc
 			if (i > span->chan_count) {
 				break;
 			}
+		} else if (direction == FTDM_RR_DOWN || direction == FTDM_RR_UP) {
+			if (i == span->last_used_index) {
+				break;
+			}
 		} else {
 			if (i == 0) {
 				break;
@@ -1873,6 +1904,9 @@ FT_DECLARE(ftdm_status_t) ftdm_channel_open_by_span(uint32_t span_id, ftdm_direc
 
 		if (request_voice_channel(check, ftdmchan, caller_data, direction)) {
 			status = FTDM_SUCCESS;
+			if (direction == FTDM_RR_UP || direction == FTDM_RR_DOWN) {
+				span->last_used_index = i;
+			}
 			break;
 		}
 			
@@ -1880,6 +1914,11 @@ FT_DECLARE(ftdm_status_t) ftdm_channel_open_by_span(uint32_t span_id, ftdm_direc
 
 		if (direction == FTDM_TOP_DOWN) {
 			i++;
+		} else if (direction == FTDM_RR_DOWN || direction == FTDM_RR_UP) {
+			if (check == best_rated) {
+				span->last_used_index = i;
+			}
+			i = rr_next(i, 1, span->chan_count, direction);
 		} else {
 			i--;
 		}
diff --git a/libs/freetdm/src/include/freetdm.h b/libs/freetdm/src/include/freetdm.h
index dce130f5be..69b90f1acd 100644
--- a/libs/freetdm/src/include/freetdm.h
+++ b/libs/freetdm/src/include/freetdm.h
@@ -144,7 +144,9 @@ typedef enum {
 /*! \brief Hunting direction (when hunting for free channels) */
 typedef enum {
 	FTDM_TOP_DOWN,
-	FTDM_BOTTOM_UP
+	FTDM_BOTTOM_UP,
+	FTDM_RR_DOWN,
+	FTDM_RR_UP,
 } ftdm_direction_t;
 
 /*! \brief I/O channel type */
diff --git a/libs/freetdm/src/include/private/ftdm_core.h b/libs/freetdm/src/include/private/ftdm_core.h
index 9222da3a42..e8ee7156f8 100644
--- a/libs/freetdm/src/include/private/ftdm_core.h
+++ b/libs/freetdm/src/include/private/ftdm_core.h
@@ -493,6 +493,7 @@ struct ftdm_span {
 	ftdm_trunk_type_t trunk_type;
 	ftdm_analog_start_type_t start_type;
 	ftdm_signal_type_t signal_type;
+	uint32_t last_used_index;
 	/* Private signaling data. Do not touch unless you are a signaling module */
 	void *signal_data;
 	fio_signal_cb_t signal_cb;