telephony: Add support for choosing a default APN

* Sometimes, the standard method of choosing the "first" available APN
   is not what we want. Consider the case where a certain provider has
   both a "normal" APN and an LTE APN. The LTE APN is what we want, but
   it's not chosen.
* Add a new overlayable value "config_preferred_apn" to handle this. A
   device can override this. The format is "apn,mcc,mnc".

Change-Id: Ia6ca4159491bee15b3f18ad7ad524b8b0ffce2f2

2 files changed, 69 insertions, 1 deletions

diff --git a/res/values/config.xml b/res/values/config.xml
new file mode 100644
index 0000000..a8807c6
--- /dev/null
+++ b/res/values/config.xml
@@ -0,0 +1,22 @@
+<?xml version="1.0" encoding="utf-8"?>
+<!-- Copyright (C) 2012 The CyanogenMod Project
+
+     Licensed under the Apache License, Version 2.0 (the "License");
+     you may not use this file except in compliance with the License.
+     You may obtain a copy of the License at
+
+          http://www.apache.org/licenses/LICENSE-2.0
+
+     Unless required by applicable law or agreed to in writing, software
+     distributed under the License is distributed on an "AS IS" BASIS,
+     WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+     See the License for the specific language governing permissions and
+     limitations under the License.
+-->
+
+<resources xmlns:xliff="urn:oasis:names:tc:xliff:document:1.2">
+
+    <!-- The preferred APN to use, in the format name,mcc,mnc
+         Leave empty to choose automatically. -->
+    <string name="config_preferred_apn"></string>
+</resources>
diff --git a/src/com/android/providers/telephony/TelephonyProvider.java b/src/com/android/providers/telephony/TelephonyProvider.java
index 5e2ed90..90be05d 100644
--- a/src/com/android/providers/telephony/TelephonyProvider.java
+++ b/src/com/android/providers/telephony/TelephonyProvider.java
@@ -39,6 +39,7 @@ import android.os.UserHandle;
 import android.provider.Telephony;
 import android.telephony.SubscriptionManager;
 import android.telephony.TelephonyManager;
+import android.text.TextUtils;
 import android.util.Log;
 import android.util.Xml;
 
@@ -252,6 +253,24 @@ public class TelephonyProvider extends ContentProvider
             if (DBG) log("dbh.createCarriersTable:-");
         }
 
+        private int getDefaultPreferredApnId(SQLiteDatabase db) {
+            int id = -1;
+            String configPref = mContext.getResources().getString(R.string.config_preferred_apn, "");
+            if (!TextUtils.isEmpty(configPref)) {
+                String[] s = configPref.split(",");
+                if (s.length == 3) {
+                    Cursor c = db.query("carriers", new String[] { "_id" },
+                            "apn='" + s[0] + "' AND mcc='" + s[1] + "' AND mnc='" + s[2] + "'",
+                            null, null, null, null);
+                    if (c.moveToFirst()) {
+                        id = c.getInt(0);
+                    }
+                    c.close();
+                }
+            }
+            return id;
+        }
+
         private void initDatabase(SQLiteDatabase db) {
             if (VDBG) log("dbh.initDatabase:+ db=" + db);
             // Read internal APNS data
@@ -681,7 +700,33 @@ public class TelephonyProvider extends ContentProvider
     private long getPreferredApnId(int subId) {
         SharedPreferences sp = getContext().getSharedPreferences(
                 PREF_FILE + subId, Context.MODE_PRIVATE);
-        return sp.getLong(COLUMN_APN_ID, -1);
+        long id = sp.getLong(COLUMN_APN_ID, -1);
+        if (id == -1) {
+            id = getDefaultPreferredApnId();
+            if (id > -1) {
+                setPreferredApnId(id, subId);
+            }
+        }
+        return id;
+    }
+
+    private long getDefaultPreferredApnId() {
+        long id = -1;
+        String configPref = getContext().getResources().getString(R.string.config_preferred_apn, "");
+        if (!TextUtils.isEmpty(configPref)) {
+            String[] s = configPref.split(",");
+            if (s.length == 3) {
+                Cursor c = mOpenHelper.getReadableDatabase().query("carriers", new String[] { "_id" },
+                        "apn='" + s[0] + "' AND mcc='" + s[1] + "' AND mnc='" + s[2] + "'",
+                        null, null, null, null);
+                if (c.moveToFirst()) {
+                    id = c.getLong(0);
+                }
+                c.close();
+            }
+        }
+        Log.d(TAG, "Preferred APN: " + id);
+        return id;
     }
 
     @Override
@@ -1211,6 +1256,7 @@ public class TelephonyProvider extends ContentProvider
         }
         setPreferredApnId((long)-1, subId);
         mOpenHelper.initDatabase(db);
+        setPreferredApnId(getDefaultPreferredApnId(), subId);
     }
 
     /**