[mutter/gnome-3-14] monitor-config: Prevent a crash applying config for a closed lid

[Rui Matos <rtcm src gnome org>]

commit c98686da9225dc020da698c1437880963e850479
Author: Rui Matos <tiagomatos gmail com>
Date:   Fri Oct 31 15:02:05 2014 +0100

    monitor-config: Prevent a crash applying config for a closed lid
    
    When a laptop's lid is closed we try to build and apply a temporary
    configuration that disables the laptop's display if we have other
    outputs.
    
    This isn't enough though, we must also check if at least one of these
    other outputs is enabled otherwise we'll try to resize the screen to
    0x0 which (rightfully) hits an assertion.
    
    https://bugzilla.gnome.org/show_bug.cgi?id=739450

 src/backends/meta-monitor-config.c |   21 +++++++++++++++++----
 1 files changed, 17 insertions(+), 4 deletions(-)
---
diff --git a/src/backends/meta-monitor-config.c b/src/backends/meta-monitor-config.c
index c97505d..8dc6b50 100644
--- a/src/backends/meta-monitor-config.c
+++ b/src/backends/meta-monitor-config.c
@@ -945,6 +945,19 @@ laptop_display_is_on (MetaConfiguration *config)
   return FALSE;
 }
 
+static gboolean
+multiple_outputs_are_enabled (MetaConfiguration *config)
+{
+  unsigned int i, enabled;
+
+  enabled = 0;
+  for (i = 0; i < config->n_outputs; i++)
+    if (config->outputs[i].enabled)
+      enabled++;
+
+  return enabled > 1;
+}
+
 static MetaConfiguration *
 make_laptop_lid_config (MetaConfiguration  *reference)
 {
@@ -954,7 +967,7 @@ make_laptop_lid_config (MetaConfiguration  *reference)
   int x_after, y_after;
   int x_offset, y_offset;
 
-  g_assert (reference->n_outputs > 1);
+  g_assert (multiple_outputs_are_enabled (reference));
 
   new = g_slice_new0 (MetaConfiguration);
   new->n_outputs = reference->n_outputs;
@@ -1025,7 +1038,7 @@ meta_monitor_config_apply_stored (MetaMonitorConfig  *self,
   if (stored)
     {
       if (self->lid_is_closed &&
-          stored->n_outputs > 1 &&
+          multiple_outputs_are_enabled (stored) &&
           laptop_display_is_on (stored))
         {
           if (apply_configuration (self, make_laptop_lid_config (stored),
@@ -1287,7 +1300,7 @@ meta_monitor_config_make_default (MetaMonitorConfig  *self,
   if (default_config != NULL)
     {
       if (self->lid_is_closed &&
-          default_config->n_outputs > 1 &&
+          multiple_outputs_are_enabled (default_config) &&
           laptop_display_is_on (default_config))
         {
           ok = apply_configuration (self, make_laptop_lid_config (default_config),
@@ -1378,7 +1391,7 @@ turn_off_laptop_display (MetaMonitorConfig  *self,
 {
   MetaConfiguration *new;
 
-  if (self->current->n_outputs == 1)
+  if (!multiple_outputs_are_enabled (self->current))
     return;
 
   new = make_laptop_lid_config (self->current);