---

stalar · michaelbausor · commit af13f62938c3 · 2017-07-06T13:50:37.000-07:00
yaml --- r: 8157 b: refs/heads/tswast-patch-1 c: 797d665 h: refs/heads/master i: 8155: 08b838f
diff --git a/[refs] b/[refs]
@@ -57,5 +57,5 @@ refs/tags/v0.18.0: 9d193c4c4b9d1c6f21515dd8e50836b9194ec9bb
 refs/tags/v0.19.0: e67b56e4d8dad5f9a7b38c9b2107c23c828f2ed5
 refs/tags/v0.20.0: 839f7fb7156535146aa1cb2c5aadd8d375d854e8
 refs/tags/v0.20.1: 370471f437f1f4f68a11e068df5cd6bf39edb1fa
-refs/heads/tswast-patch-1: 2a922078f60e5e6c70d14a556b600f93d8b05b77
+refs/heads/tswast-patch-1: 797d665b84c9a518629a150365d98b846668a548
 refs/heads/pubsub-streaming-pull: 19262b752ee874eb2ca3b950eb2aef44d5a5267b
diff --git a/branches/tswast-patch-1/google-cloud-logging/src/main/java/com/google/cloud/logging/LoggingImpl.java b/branches/tswast-patch-1/google-cloud-logging/src/main/java/com/google/cloud/logging/LoggingImpl.java
@@ -580,7 +580,9 @@ public void onFailure(Throwable t) {
                 }
               }
             });
-        pendingWrites.add(writeFuture);
+        synchronized (writeLock) {
+          pendingWrites.add(writeFuture);
+        }
         break;
     }
   }
diff --git a/branches/tswast-patch-1/google-cloud-logging/src/test/java/com/google/cloud/logging/LoggingImplTest.java b/branches/tswast-patch-1/google-cloud-logging/src/test/java/com/google/cloud/logging/LoggingImplTest.java
@@ -70,6 +70,7 @@
 import java.util.List;
 import java.util.Map;
 import java.util.concurrent.ExecutionException;
+import java.util.concurrent.atomic.AtomicInteger;
 import org.easymock.EasyMock;
 import org.junit.After;
 import org.junit.Before;
@@ -1448,5 +1449,43 @@ public void run() {
     flushWaiter.join(1000);
     assertFalse(flushWaiter.isAlive());
   }
+
+  @Test
+  public void testFlushStress() throws InterruptedException {
+    SettableApiFuture<WriteLogEntriesResponse> mockRpcResponse = SettableApiFuture.create();
+    mockRpcResponse.set(null);
+    replay(rpcFactoryMock);
+    logging = options.getService();
+    WriteLogEntriesRequest request = WriteLogEntriesRequest.newBuilder()
+        .addAllEntries(Iterables.transform(ImmutableList.of(LOG_ENTRY1),
+            LogEntry.toPbFunction(PROJECT)))
+        .build();
+
+    Thread[] threads = new Thread[100];
+    EasyMock.expect(loggingRpcMock.write(request)).andReturn(mockRpcResponse).times(threads.length);
+    EasyMock.replay(loggingRpcMock);
+
+    // log and flush concurrently in many threads to trigger a ConcurrentModificationException
+    final AtomicInteger exceptions = new AtomicInteger(0);
+    for (int i = 0; i < threads.length; i++) {
+      threads[i] = new Thread() {
+        @Override
+        public void run() {
+          try {
+            logging.write(ImmutableList.of(LOG_ENTRY1));
+            logging.flush();
+          } catch (Exception ex) {
+            exceptions.incrementAndGet();
+          }
+        }
+      };
+      threads[i].start();
+    }
+    for (int i = 0; i < threads.length; i++) {
+      threads[i].join();
+    }
+    assertSame(0, exceptions.get());
+  }
+
 }
 

Original file line number	Diff line number	Diff line change
`@@ -580,7 +580,9 @@ public void onFailure(Throwable t) {`
`580`	`580`	`}`
`581`	`581`	`}`
`582`	`582`	`});`
`583`		`- pendingWrites.add(writeFuture);`
	`583`	`+ synchronized (writeLock) {`
	`584`	`+ pendingWrites.add(writeFuture);`
	`585`	`+ }`
`584`	`586`	`break;`
`585`	`587`	`}`
`586`	`588`	`}`