Prevent duplicate jobs for same download.

Before this CL, we could have started duplicate jobs for the same
download ID in parallel.  Now, we ignore duplicate jobs for the same
download.  This requires us to only reschedule a job after removing
it from mActiveThreads, so slight refactoring there.

Test: bit DownloadProviderTests:*
Bug: 36227864
Change-Id: I3103480859c5eb9488817165187c5dae05b2d843

2 files changed, 14 insertions, 3 deletions

diff --git a/src/com/android/providers/downloads/DownloadJobService.java b/src/com/android/providers/downloads/DownloadJobService.java
index 0ce4266a..d09738c2 100644
--- a/src/com/android/providers/downloads/DownloadJobService.java
+++ b/src/com/android/providers/downloads/DownloadJobService.java
@@ -66,6 +66,10 @@ public class DownloadJobService extends JobService {
 
         final DownloadThread thread;
         synchronized (mActiveThreads) {
+            if (mActiveThreads.indexOfKey(id) >= 0) {
+                Log.w(TAG, "Odd, already running download " + id);
+                return false;
+            }
             thread = new DownloadThread(this, params, info);
             mActiveThreads.put(id, thread);
         }
@@ -93,14 +97,20 @@ public class DownloadJobService extends JobService {
     }
 
     public void jobFinishedInternal(JobParameters params, boolean needsReschedule) {
+        final int id = params.getJobId();
+
         synchronized (mActiveThreads) {
             mActiveThreads.remove(params.getJobId());
         }
+        if (needsReschedule) {
+            Helpers.scheduleJob(this, DownloadInfo.queryDownloadInfo(this, id));
+        }
 
         // Update notifications one last time while job is protecting us
         mObserver.onChange(false);
 
-        jobFinished(params, needsReschedule);
+        // We do our own rescheduling above
+        jobFinished(params, false);
     }
 
     private ContentObserver mObserver = new ContentObserver(Helpers.getAsyncHandler()) {
diff --git a/src/com/android/providers/downloads/DownloadThread.java b/src/com/android/providers/downloads/DownloadThread.java
index 9c920053..1476f4a0 100644
--- a/src/com/android/providers/downloads/DownloadThread.java
+++ b/src/com/android/providers/downloads/DownloadThread.java
@@ -384,6 +384,7 @@ public class DownloadThread extends Thread {
             mNetworkPolicy.unregisterListener(mPolicyListener);
         }
 
+        boolean needsReschedule = false;
         if (Downloads.Impl.isStatusCompleted(mInfoDelta.mStatus)) {
             if (mInfo.shouldScanFile(mInfoDelta.mStatus)) {
                 DownloadScanner.requestScanBlocking(mContext, mInfo.mId, mInfoDelta.mFileName,
@@ -392,10 +393,10 @@ public class DownloadThread extends Thread {
         } else if (mInfoDelta.mStatus == STATUS_WAITING_TO_RETRY
                 || mInfoDelta.mStatus == STATUS_WAITING_FOR_NETWORK
                 || mInfoDelta.mStatus == STATUS_QUEUED_FOR_WIFI) {
-            Helpers.scheduleJob(mContext, DownloadInfo.queryDownloadInfo(mContext, mId));
+            needsReschedule = true;
         }
 
-        mJobService.jobFinishedInternal(mParams, false);
+        mJobService.jobFinishedInternal(mParams, needsReschedule);
     }
 
     public void requestShutdown() {