audio: new routing strategies and stream types

Added new routing strategies and stream type for internal use
by audio policy manager and audio flinger:
- One for accessibility to allow different routing than media
- One for re-routing (remote submix) in preparation of dynamic
policies
- Added stream type for "internal" audio flinger tracks used
for audio patches and duplication.

Bug: 18067208.
Change-Id: I88f884b552e51e4a49c29125e5a1204cf58ff434

5 files changed, 40 insertions, 18 deletions

diff --git a/services/audioflinger/AudioFlinger.cpp b/services/audioflinger/AudioFlinger.cpp
index ea9d7d3..8acfc07 100644
--- a/services/audioflinger/AudioFlinger.cpp
+++ b/services/audioflinger/AudioFlinger.cpp
@@ -891,6 +891,21 @@ bool AudioFlinger::masterMute_l() const
     return mMasterMute;
 }
 
+status_t AudioFlinger::checkStreamType(audio_stream_type_t stream) const
+{
+    if (uint32_t(stream) >= AUDIO_STREAM_CNT) {
+        ALOGW("setStreamVolume() invalid stream %d", stream);
+        return BAD_VALUE;
+    }
+    pid_t caller = IPCThreadState::self()->getCallingPid();
+    if (uint32_t(stream) >= AUDIO_STREAM_PUBLIC_CNT && caller != getpid_cached) {
+        ALOGW("setStreamVolume() pid %d cannot use internal stream type %d", caller, stream);
+        return PERMISSION_DENIED;
+    }
+
+    return NO_ERROR;
+}
+
 status_t AudioFlinger::setStreamVolume(audio_stream_type_t stream, float value,
         audio_io_handle_t output)
 {
@@ -899,10 +914,11 @@ status_t AudioFlinger::setStreamVolume(audio_stream_type_t stream, float value,
         return PERMISSION_DENIED;
     }
 
-    if (uint32_t(stream) >= AUDIO_STREAM_CNT) {
-        ALOGE("setStreamVolume() invalid stream %d", stream);
-        return BAD_VALUE;
+    status_t status = checkStreamType(stream);
+    if (status != NO_ERROR) {
+        return status;
     }
+    ALOG_ASSERT(stream != AUDIO_STREAM_PATCH, "attempt to change AUDIO_STREAM_PATCH volume");
 
     AutoMutex lock(mLock);
     PlaybackThread *thread = NULL;
@@ -933,8 +949,13 @@ status_t AudioFlinger::setStreamMute(audio_stream_type_t stream, bool muted)
         return PERMISSION_DENIED;
     }
 
-    if (uint32_t(stream) >= AUDIO_STREAM_CNT ||
-        uint32_t(stream) == AUDIO_STREAM_ENFORCED_AUDIBLE) {
+    status_t status = checkStreamType(stream);
+    if (status != NO_ERROR) {
+        return status;
+    }
+    ALOG_ASSERT(stream != AUDIO_STREAM_PATCH, "attempt to mute AUDIO_STREAM_PATCH");
+
+    if (uint32_t(stream) == AUDIO_STREAM_ENFORCED_AUDIBLE) {
         ALOGE("setStreamMute() invalid stream %d", stream);
         return BAD_VALUE;
     }
@@ -949,7 +970,8 @@ status_t AudioFlinger::setStreamMute(audio_stream_type_t stream, bool muted)
 
 float AudioFlinger::streamVolume(audio_stream_type_t stream, audio_io_handle_t output) const
 {
-    if (uint32_t(stream) >= AUDIO_STREAM_CNT) {
+    status_t status = checkStreamType(stream);
+    if (status != NO_ERROR) {
         return 0.0f;
     }
 
@@ -970,7 +992,8 @@ float AudioFlinger::streamVolume(audio_stream_type_t stream, audio_io_handle_t o
 
 bool AudioFlinger::streamMute(audio_stream_type_t stream) const
 {
-    if (uint32_t(stream) >= AUDIO_STREAM_CNT) {
+    status_t status = checkStreamType(stream);
+    if (status != NO_ERROR) {
         return true;
     }
 
diff --git a/services/audioflinger/AudioFlinger.h b/services/audioflinger/AudioFlinger.h
index 4fb372d..aa0af1f 100644
--- a/services/audioflinger/AudioFlinger.h
+++ b/services/audioflinger/AudioFlinger.h
@@ -745,6 +745,8 @@ private:
     void        closeInputInternal_l(sp<RecordThread> thread);
     void        setAudioHwSyncForSession_l(PlaybackThread *thread, audio_session_t sessionId);
 
+    status_t    checkStreamType(audio_stream_type_t stream) const;
+
 #ifdef TEE_SINK
     // all record threads serially share a common tee sink, which is re-created on format change
     sp<NBAIO_Sink>   mRecordTeeSink;
diff --git a/services/audioflinger/Threads.cpp b/services/audioflinger/Threads.cpp
index 0f11b34..792419f 100644
--- a/services/audioflinger/Threads.cpp
+++ b/services/audioflinger/Threads.cpp
@@ -1224,15 +1224,12 @@ AudioFlinger::PlaybackThread::PlaybackThread(const sp<AudioFlinger>& audioFlinge
 
     readOutputParameters_l();
 
-    // mStreamTypes[AUDIO_STREAM_CNT] is initialized by stream_type_t default constructor
-    // There is no AUDIO_STREAM_MIN, and ++ operator does not compile
+    // ++ operator does not compile
     for (audio_stream_type_t stream = AUDIO_STREAM_MIN; stream < AUDIO_STREAM_CNT;
             stream = (audio_stream_type_t) (stream + 1)) {
         mStreamTypes[stream].volume = mAudioFlinger->streamVolume_l(stream);
         mStreamTypes[stream].mute = mAudioFlinger->streamMute_l(stream);
     }
-    // mStreamTypes[AUDIO_STREAM_CNT] exists but isn't explicitly initialized here,
-    // because mAudioFlinger doesn't have one to copy from
 }
 
 AudioFlinger::PlaybackThread::~PlaybackThread()
@@ -4746,7 +4743,7 @@ void AudioFlinger::DuplicatingThread::addOutputTrack(MixerThread *thread)
                                             frameCount,
                                             IPCThreadState::self()->getCallingUid());
     if (outputTrack->cblk() != NULL) {
-        thread->setStreamVolume(AUDIO_STREAM_CNT, 1.0f);
+        thread->setStreamVolume(AUDIO_STREAM_PATCH, 1.0f);
         mOutputTracks.add(outputTrack);
         ALOGV("addOutputTrack() track %p, on thread %p", outputTrack, thread);
         updateWaitTime_l();
diff --git a/services/audioflinger/Threads.h b/services/audioflinger/Threads.h
index bb9aa18..119e495 100644
--- a/services/audioflinger/Threads.h
+++ b/services/audioflinger/Threads.h
@@ -727,9 +727,7 @@ private:
     void        dumpTracks(int fd, const Vector<String16>& args);
 
     SortedVector< sp<Track> >       mTracks;
-    // mStreamTypes[] uses 1 additional stream type internally for the OutputTrack used by
-    // DuplicatingThread
-    stream_type_t                   mStreamTypes[AUDIO_STREAM_CNT + 1];
+    stream_type_t                   mStreamTypes[AUDIO_STREAM_CNT];
     AudioStreamOut                  *mOutput;
 
     float                           mMasterVolume;
diff --git a/services/audioflinger/Tracks.cpp b/services/audioflinger/Tracks.cpp
index 037c73b..aa708ec 100644
--- a/services/audioflinger/Tracks.cpp
+++ b/services/audioflinger/Tracks.cpp
@@ -1657,8 +1657,9 @@ AudioFlinger::PlaybackThread::OutputTrack::OutputTrack(
             audio_channel_mask_t channelMask,
             size_t frameCount,
             int uid)
-    :   Track(playbackThread, NULL, AUDIO_STREAM_CNT, sampleRate, format, channelMask, frameCount,
-                NULL, 0, 0, uid, IAudioFlinger::TRACK_DEFAULT, TYPE_OUTPUT),
+    :   Track(playbackThread, NULL, AUDIO_STREAM_PATCH,
+              sampleRate, format, channelMask, frameCount,
+              NULL, 0, 0, uid, IAudioFlinger::TRACK_DEFAULT, TYPE_OUTPUT),
     mActive(false), mSourceThread(sourceThread), mClientProxy(NULL)
 {
 
@@ -1873,7 +1874,8 @@ AudioFlinger::PlaybackThread::PatchTrack::PatchTrack(PlaybackThread *playbackThr
                                                      size_t frameCount,
                                                      void *buffer,
                                                      IAudioFlinger::track_flags_t flags)
-    :   Track(playbackThread, NULL, AUDIO_STREAM_CNT, sampleRate, format, channelMask, frameCount,
+    :   Track(playbackThread, NULL, AUDIO_STREAM_PATCH,
+              sampleRate, format, channelMask, frameCount,
               buffer, 0, 0, getuid(), flags, TYPE_PATCH),
               mProxy(new ClientProxy(mCblk, mBuffer, frameCount, mFrameSize, true, true))
 {