Support for posting messages and synchronously waiting for a response.

Change-Id: Id6c7a08c34fd5cb6c4632f78ece9e7898b29e52c

2 files changed, 23 insertions, 1 deletions

diff --git a/include/media/stagefright/foundation/ALooperRoster.h b/include/media/stagefright/foundation/ALooperRoster.h
index c1bd4ed..2e5fd73 100644
--- a/include/media/stagefright/foundation/ALooperRoster.h
+++ b/include/media/stagefright/foundation/ALooperRoster.h
@@ -31,9 +31,14 @@ struct ALooperRoster {
 
     void unregisterHandler(ALooper::handler_id handlerID);
 
-    void postMessage(const sp<AMessage> &msg, int64_t delayUs = 0);
+    status_t postMessage(const sp<AMessage> &msg, int64_t delayUs = 0);
     void deliverMessage(const sp<AMessage> &msg);
 
+    status_t postAndAwaitResponse(
+            const sp<AMessage> &msg, sp<AMessage> *response);
+
+    void postReply(uint32_t replyID, const sp<AMessage> &reply);
+
     sp<ALooper> findLooper(ALooper::handler_id handlerID);
 
 private:
@@ -45,6 +50,12 @@ private:
     Mutex mLock;
     KeyedVector<ALooper::handler_id, HandlerInfo> mHandlers;
     ALooper::handler_id mNextHandlerID;
+    uint32_t mNextReplyID;
+    Condition mRepliesCondition;
+
+    KeyedVector<uint32_t, sp<AMessage> > mReplies;
+
+    status_t postMessage_l(const sp<AMessage> &msg, int64_t delayUs);
 
     DISALLOW_EVIL_CONSTRUCTORS(ALooperRoster);
 };
diff --git a/include/media/stagefright/foundation/AMessage.h b/include/media/stagefright/foundation/AMessage.h
index 72dc730..7ec54aa 100644
--- a/include/media/stagefright/foundation/AMessage.h
+++ b/include/media/stagefright/foundation/AMessage.h
@@ -72,6 +72,17 @@ struct AMessage : public RefBase {
 
     void post(int64_t delayUs = 0);
 
+    // Posts the message to its target and waits for a response (or error)
+    // before returning.
+    status_t postAndAwaitResponse(sp<AMessage> *response);
+
+    // If this returns true, the sender of this message is synchronously
+    // awaiting a response, the "replyID" can be used to send the response
+    // via "postReply" below.
+    bool senderAwaitsResponse(uint32_t *replyID) const;
+
+    void postReply(uint32_t replyID);
+
     // Performs a deep-copy of "this", contained messages are in turn "dup'ed".
     // Warning: RefBase items, i.e. "objects" are _not_ copied but only have
     // their refcount incremented.