From 733d322cf594bb29a57e5e44c5c8100c4cf3ffcc Mon Sep 17 00:00:00 2001
From: "Philip P. Moltmann" <moltmann@google.com>
Date: Mon, 28 Nov 2016 16:37:47 -0800
Subject: [PATCH] Consider priority when launching a USB app

If there are differnet priorities only consider the acitities with the
highest priorities. Esp, if there is only one app with the highest
priority launch it directly.

This enables an interesting use case:
If a priviledged app wants to always be launched for a device it can
just set the priority to >0. As it is also on system/ the user
_will_not_ get a confirmation dialog and the app will always be directly
launched.

Test: Added app with higher priority to device and saw it to get
auto-selected.
Fixes: 28595282

Change-Id: Ia2c9afa00b5a6e8a00b30a01442da62dd0e33961
---
 .../usb/UsbProfileGroupSettingsManager.java   | 64 +++++++++++++++++--
 1 file changed, 58 insertions(+), 6 deletions(-)

diff --git a/services/usb/java/com/android/server/usb/UsbProfileGroupSettingsManager.java b/services/usb/java/com/android/server/usb/UsbProfileGroupSettingsManager.java
index e03a14f41ce24..d44005268683f 100644
--- a/services/usb/java/com/android/server/usb/UsbProfileGroupSettingsManager.java
+++ b/services/usb/java/com/android/server/usb/UsbProfileGroupSettingsManager.java
@@ -16,6 +16,8 @@
 
 package com.android.server.usb;
 
+import static com.android.internal.app.IntentForwarderActivity.FORWARD_INTENT_TO_MANAGED_PROFILE;
+
 import android.annotation.NonNull;
 import android.annotation.Nullable;
 import android.content.ActivityNotFoundException;
@@ -41,6 +43,8 @@ import android.os.UserManager;
 import android.util.AtomicFile;
 import android.util.Log;
 import android.util.Slog;
+import android.util.SparseArray;
+import android.util.SparseIntArray;
 import android.util.Xml;
 
 import com.android.internal.annotations.GuardedBy;
@@ -50,6 +54,8 @@ import com.android.internal.util.FastXmlSerializer;
 import com.android.internal.util.IndentingPrintWriter;
 import com.android.internal.util.XmlUtils;
 
+import libcore.io.IoUtils;
+
 import org.xmlpull.v1.XmlPullParser;
 import org.xmlpull.v1.XmlPullParserException;
 import org.xmlpull.v1.XmlSerializer;
@@ -66,10 +72,6 @@ import java.util.Iterator;
 import java.util.List;
 import java.util.Map;
 
-import libcore.io.IoUtils;
-
-import static com.android.internal.app.IntentForwarderActivity.FORWARD_INTENT_TO_MANAGED_PROFILE;
-
 class UsbProfileGroupSettingsManager {
     private static final String TAG = UsbProfileGroupSettingsManager.class.getSimpleName();
     private static final boolean DEBUG = false;
@@ -873,6 +875,56 @@ class UsbProfileGroupSettingsManager {
         return resolveInfos;
     }
 
+    /**
+     * Only return those matches with the highest priority.
+     *
+     * @param matches All matches, some might have lower priority
+     *
+     * @return The matches with the highest priority
+     */
+    @NonNull
+    private ArrayList<ResolveInfo> preferHighPriority(
+            @NonNull ArrayList<ResolveInfo> matches) {
+        SparseArray<ArrayList<ResolveInfo>> highestPriorityMatchesByUserId = new SparseArray<>();
+        SparseIntArray highestPriorityByUserId = new SparseIntArray();
+
+        // Create list of highest priority matches per user in highestPriorityMatchesByUserId
+        int numMatches = matches.size();
+        for (int matchNum = 0; matchNum < numMatches; matchNum++) {
+            ResolveInfo match = matches.get(matchNum);
+
+            // If this a previously unknown user?
+            if (highestPriorityByUserId.indexOfKey(match.targetUserId) < 0) {
+                highestPriorityByUserId.put(match.targetUserId, Integer.MIN_VALUE);
+                highestPriorityMatchesByUserId.put(match.targetUserId, new ArrayList<>());
+            }
+
+            // Find current highest priority matches for the current user
+            int highestPriority = highestPriorityByUserId.get(match.targetUserId);
+            ArrayList<ResolveInfo> highestPriorityMatches = highestPriorityMatchesByUserId.get(
+                    match.targetUserId);
+
+            if (match.priority == highestPriority) {
+                highestPriorityMatches.add(match);
+            } else if (match.priority > highestPriority) {
+                highestPriorityByUserId.put(match.targetUserId, match.priority);
+
+                highestPriorityMatches.clear();
+                highestPriorityMatches.add(match);
+            }
+        }
+
+        // Combine all users back together. This means that all matches have the same priority for a
+        // user. Matches for different users might have different priority.
+        ArrayList<ResolveInfo> combinedMatches = new ArrayList<>();
+        int numMatchArrays = highestPriorityMatchesByUserId.size();
+        for (int matchArrayNum = 0; matchArrayNum < numMatchArrays; matchArrayNum++) {
+            combinedMatches.addAll(highestPriorityMatchesByUserId.valueAt(matchArrayNum));
+        }
+
+        return combinedMatches;
+    }
+
     private final ArrayList<ResolveInfo> getDeviceMatchesLocked(UsbDevice device, Intent intent) {
         ArrayList<ResolveInfo> matches = new ArrayList<ResolveInfo>();
         List<ResolveInfo> resolveInfos = queryIntentActivitiesForAllProfiles(intent);
@@ -883,7 +935,7 @@ class UsbProfileGroupSettingsManager {
                 matches.add(resolveInfo);
             }
         }
-        return matches;
+        return preferHighPriority(matches);
     }
 
     private final ArrayList<ResolveInfo> getAccessoryMatchesLocked(
@@ -897,7 +949,7 @@ class UsbProfileGroupSettingsManager {
                 matches.add(resolveInfo);
             }
         }
-        return matches;
+        return preferHighPriority(matches);
     }
 
     public void deviceAttached(UsbDevice device) {