From 3f7b652cd3ebced09e1d33d7683361bcedef2792 Mon Sep 17 00:00:00 2001
From: David Christie <dnchrist@google.com>
Date: Tue, 6 Aug 2013 19:19:08 -0700
Subject: [PATCH] Add helper methods to set/query the location master switch.
 Consolidates the logic of exactly what the master switch means so that if we
 change in the future, we don't have to find all the different parts of the
 code that use it (location settings, location quick settings, power widget,
 etc).

Change-Id: Ib918143b82e16541f0873c4d9141adb11fb815fc
(cherry picked from commit db3720d42dcaa1d26022a392d24f60d0b711f3b7)
---
 core/java/android/provider/Settings.java | 56 ++++++++++++++++++++----
 1 file changed, 47 insertions(+), 9 deletions(-)

diff --git a/core/java/android/provider/Settings.java b/core/java/android/provider/Settings.java
index 130123fb9d2cb..1ba39b3165a39 100644
--- a/core/java/android/provider/Settings.java
+++ b/core/java/android/provider/Settings.java
@@ -33,6 +33,7 @@ import android.content.res.Configuration;
 import android.content.res.Resources;
 import android.database.Cursor;
 import android.database.SQLException;
+import android.location.LocationManager;
 import android.net.ConnectivityManager;
 import android.net.Uri;
 import android.net.wifi.WifiManager;
@@ -737,6 +738,10 @@ public final class Settings {
     private static final String TAG = "Settings";
     private static final boolean LOCAL_LOGV = false;
 
+    // Lock ensures that when enabling/disabling the master location switch, we don't end up
+    // with a partial enable/disable state in multi-threaded situations.
+    private static final Object mLocationSettingsLock = new Object();
+
     public static class SettingNotFoundException extends AndroidException {
         public SettingNotFoundException(String msg) {
             super(msg);
@@ -4302,6 +4307,20 @@ public final class Settings {
             return isLocationProviderEnabledForUser(cr, provider, UserHandle.myUserId());
         }
 
+        /**
+         * Helper method for determining if the location master switch is enabled.
+         * @param cr the content resolver to use
+         * @return true if the master switch is enabled
+         * @hide
+         */
+        public static final boolean isLocationMasterSwitchEnabled(ContentResolver cr) {
+            int uid = UserHandle.myUserId();
+            synchronized (mLocationSettingsLock) {
+                return isLocationProviderEnabledForUser(cr, LocationManager.NETWORK_PROVIDER, uid)
+                        || isLocationProviderEnabledForUser(cr, LocationManager.GPS_PROVIDER, uid);
+            }
+        }
+
         /**
          * Helper method for determining if a location provider is enabled.
          * @param cr the content resolver to use
@@ -4327,6 +4346,23 @@ public final class Settings {
             setLocationProviderEnabledForUser(cr, provider, enabled, UserHandle.myUserId());
         }
 
+        /**
+         * Thread-safe method for enabling or disabling the location master switch.
+         *
+         * @param cr the content resolver to use
+         * @param enabled true if master switch should be enabled
+         * @hide
+         */
+        public static final void setLocationMasterSwitchEnabled(ContentResolver cr,
+                boolean enabled) {
+            int uid = UserHandle.myUserId();
+            synchronized (mLocationSettingsLock) {
+                setLocationProviderEnabledForUser(cr, LocationManager.GPS_PROVIDER, enabled, uid);
+                setLocationProviderEnabledForUser(cr, LocationManager.NETWORK_PROVIDER, enabled,
+                        uid);
+            }
+        }
+
         /**
          * Thread-safe method for enabling or disabling a single location provider.
          * @param cr the content resolver to use
@@ -4337,16 +4373,18 @@ public final class Settings {
          */
         public static final void setLocationProviderEnabledForUser(ContentResolver cr,
                 String provider, boolean enabled, int userId) {
-            // to ensure thread safety, we write the provider name with a '+' or '-'
-            // and let the SettingsProvider handle it rather than reading and modifying
-            // the list of enabled providers.
-            if (enabled) {
-                provider = "+" + provider;
-            } else {
-                provider = "-" + provider;
+            synchronized (mLocationSettingsLock) {
+                // to ensure thread safety, we write the provider name with a '+' or '-'
+                // and let the SettingsProvider handle it rather than reading and modifying
+                // the list of enabled providers.
+                if (enabled) {
+                    provider = "+" + provider;
+                } else {
+                    provider = "-" + provider;
+                }
+                putStringForUser(cr, Settings.Secure.LOCATION_PROVIDERS_ALLOWED, provider,
+                        userId);
             }
-            putStringForUser(cr, Settings.Secure.LOCATION_PROVIDERS_ALLOWED, provider,
-                    userId);
         }
     }