From 339229e4c698c61e20a28bfc33d8501490891427 Mon Sep 17 00:00:00 2001
From: Gary Ching-Pang Lin <chingpang@gmail.com>
Date: Tue, 20 Sep 2011 16:36:35 +0800
Subject: [PATCH] core: improving handling of rfkill (bgo #655773)

This commit improves the handling of rfkill.

- The original two passes check gathers the states of platform
  and non-platform switches in two separate loops. Now we gather
  the both states in one loop and determine the final states later.

- A new rule is used to determine the states of switches.

  if (platform_state == UNBLOCKED)
          choose non_platform_state;
  else
          choose platform_state;

  The state is UNBLOCKED if and only if both the platform and
  non-platform switches are unblocked, so the ambiguous state in
  bgo#655773 will not happen.

  Original code always preferred the platform switch state over
  the device switch state, so if the platform switch was UNBLOCKED
  but the device was BLOCKED, NM would treat the device as
  UNBLOCKED and try to activate it, and obviously fail.
---
 src/nm-udev-manager.c | 70 +++++++++++++------------------------------
 1 file changed, 21 insertions(+), 49 deletions(-)

diff --git a/src/nm-udev-manager.c b/src/nm-udev-manager.c
index 72501c280d..3e855b787a 100644
--- a/src/nm-udev-manager.c
+++ b/src/nm-udev-manager.c
@@ -195,78 +195,50 @@ recheck_killswitches (NMUdevManager *self)
 	NMUdevManagerPrivate *priv = NM_UDEV_MANAGER_GET_PRIVATE (self);
 	GSList *iter;
 	RfKillState poll_states[RFKILL_TYPE_MAX];
+	RfKillState platform_states[RFKILL_TYPE_MAX];
 	gboolean platform_checked[RFKILL_TYPE_MAX];
 	int i;
 
 	/* Default state is unblocked */
 	for (i = 0; i < RFKILL_TYPE_MAX; i++) {
 		poll_states[i] = RFKILL_UNBLOCKED;
+		platform_states[i] = RFKILL_UNBLOCKED;
 		platform_checked[i] = FALSE;
 	}
 
-	/* Perform two passes here; the first pass is for non-platform switches,
-	 * which typically if hardkilled cannot be changed except by a physical
-	 * hardware switch.  The second pass checks platform killswitches, which
-	 * take precedence over device killswitches, because typically platform
-	 * killswitches control device killswitches.  That is, a hardblocked device
-	 * switch can often be unblocked by a platform switch.  Thus if we have
-	 * a hardblocked device switch and a softblocked platform switch, the
-	 * combined state should be softblocked since the platform switch can be
-	 * unblocked to change the device switch.
-	 */
-
-	/* Device switches first */
+	/* Poll the states of all killswitches */
 	for (iter = priv->killswitches; iter; iter = g_slist_next (iter)) {
 		Killswitch *ks = iter->data;
 		GUdevDevice *device;
 		RfKillState dev_state;
 		int sysfs_state;
 
-		if (ks->platform == FALSE) {
-			device = g_udev_client_query_by_subsystem_and_name (priv->client, "rfkill", ks->name);
-			if (device) {
-				sysfs_state = g_udev_device_get_property_as_int (device, "RFKILL_STATE");
-				dev_state = sysfs_state_to_nm_state (sysfs_state);
+		device = g_udev_client_query_by_subsystem_and_name (priv->client, "rfkill", ks->name);
+		if (device) {
+			sysfs_state = g_udev_device_get_property_as_int (device, "RFKILL_STATE");
+			dev_state = sysfs_state_to_nm_state (sysfs_state);
+			if (ks->platform == FALSE) {
 				if (dev_state > poll_states[ks->rtype])
 					poll_states[ks->rtype] = dev_state;
-				g_object_unref (device);
-			}
-		}
-	}
-
-	/* Platform switches next; their state overwrites device state */
-	for (iter = priv->killswitches; iter; iter = g_slist_next (iter)) {
-		Killswitch *ks = iter->data;
-		GUdevDevice *device;
-		RfKillState dev_state;
-		int sysfs_state;
-
-		if (ks->platform == TRUE) {
-			device = g_udev_client_query_by_subsystem_and_name (priv->client, "rfkill", ks->name);
-			if (device) {
-				sysfs_state = g_udev_device_get_property_as_int (device, "RFKILL_STATE");
-				dev_state = sysfs_state_to_nm_state (sysfs_state);
-
-				if (platform_checked[ks->rtype] == FALSE) {
-					/* Overwrite device state with platform state for first
-					 * platform switch found.
-					 */
-					poll_states[ks->rtype] = dev_state;
-					platform_checked[ks->rtype] = TRUE;
-				} else {
-					/* If there are multiple platform switches of the same type,
-					 * take the "worst" state for all of that type.
-					 */
-					if (dev_state > poll_states[ks->rtype])
-						poll_states[ks->rtype] = dev_state;
-				}
-				g_object_unref (device);
+			} else {
+				platform_checked[ks->rtype] = TRUE;
+				if (dev_state > platform_states[ks->rtype])
+					platform_states[ks->rtype] = dev_state;
 			}
+			g_object_unref (device);
 		}
 	}
 
 	/* Log and emit change signal for final rfkill states */
 	for (i = 0; i < RFKILL_TYPE_MAX; i++) {
+		if (platform_checked[i] == TRUE) {
+			/* blocked platform switch state overrides device state, otherwise
+			 * let the device state stand. (bgo #655773)
+			 */
+			if (platform_states[i] != RFKILL_UNBLOCKED)
+				poll_states[i] = platform_states[i];
+		}
+
 		if (poll_states[i] != priv->rfkill_states[i]) {
 			nm_log_dbg (LOGD_RFKILL, "%s rfkill state now '%s'",
 			            rfkill_type_to_desc (i),