AudioPolicyManager: distinguish between mirroring and rerouting

In the screen mirroring case, the notification manager queries
 the policy to see if media "is playing remotely": if yes, it
 will not request audio focus before playing a notification.
This is the correct behavior for screen mirroring, but doesn't
 work when audio is rerouted to an external policy.
This change consists in not reporting "remote" activity when
 playing to a mix of an external policy by looking at the address
 of the output on which playback is active for the given stream
 type.

Bug 16009464

Change-Id: Iebbf5a8c738ab36c1cf2055e921c0a3472503125

2 files changed, 8 insertions, 2 deletions

diff --git a/services/audiopolicy/AudioPolicyManager.cpp b/services/audiopolicy/AudioPolicyManager.cpp
index 68f3802..9918b6f 100644
--- a/services/audiopolicy/AudioPolicyManager.cpp
+++ b/services/audiopolicy/AudioPolicyManager.cpp
@@ -921,7 +921,6 @@ status_t AudioPolicyManager::getOutputForAttr(const audio_attributes_t *attr,
     ALOGV("getOutputForAttr() usage=%d, content=%d, tag=%s flags=%08x",
             attributes.usage, attributes.content_type, attributes.tags, attributes.flags);
 
-    // TODO this is where filtering for custom policies (rerouting, dynamic sources) will go
     routing_strategy strategy = (routing_strategy) getStrategyForAttr(&attributes);
     audio_devices_t device = getDeviceForStrategy(strategy, false /*fromCache*/);
 
@@ -1962,7 +1961,12 @@ bool AudioPolicyManager::isStreamActiveRemotely(audio_stream_type_t stream,
         const sp<AudioOutputDescriptor> outputDesc = mOutputs.valueAt(i);
         if (((outputDesc->device() & APM_AUDIO_OUT_DEVICE_REMOTE_ALL) != 0) &&
                 outputDesc->isStreamActive(stream, inPastMs, sysTime)) {
-            return true;
+            // only consider empty or "0" address to only qualify the screen mirroring case
+            // as "remote playback" (vs rerouting when the output is going to a dynamic policy)
+            if (outputDesc->mPolicyMixAddress == String8("")
+                    || outputDesc->mPolicyMixAddress == String8("0")) {
+                return true;
+            }
         }
     }
     return false;
diff --git a/services/audiopolicy/AudioPolicyManager.h b/services/audiopolicy/AudioPolicyManager.h
index 4214131..3eef8fe 100644
--- a/services/audiopolicy/AudioPolicyManager.h
+++ b/services/audiopolicy/AudioPolicyManager.h
@@ -155,6 +155,8 @@ public:
         // return whether a stream is playing remotely, override to change the definition of
         //   local/remote playback, used for instance by notification manager to not make
         //   media players lose audio focus when not playing locally
+        //   For the base implementation, "remotely" means playing during screen mirroring which
+        //   uses an output for playback with a non-empty, non "0" address.
         virtual bool isStreamActiveRemotely(audio_stream_type_t stream, uint32_t inPastMs = 0) const;
         virtual bool isSourceActive(audio_source_t source) const;