Revert "Revert "AudioTrack: Add getUnderrunCount()""

This reverts commit 0ac70888d3f08b694e3e31939f2cfb90ce5e0f58.

The first revert was not needed. It was made to fix a broken build. But the break was from a different CL. SO I am reverting the revert.

Change-Id: Iad30209a38f9a0af18d684e44f033a49f32af778

diff --git a/core/jni/android_media_AudioTrack.cpp b/core/jni/android_media_AudioTrack.cpp
index 42f3fb0..bc83b7f 100644 (file)
--- a/core/jni/android_media_AudioTrack.cpp
+++ b/core/jni/android_media_AudioTrack.cpp
@@ -857,6 +857,17 @@ static jint android_media_AudioTrack_get_latency(JNIEnv *env,  jobject thiz) {
     return (jint)lpTrack->latency();
 }
 
+// ----------------------------------------------------------------------------
+static jint android_media_AudioTrack_get_underrun_count(JNIEnv *env,  jobject thiz) {
+    sp<AudioTrack> lpTrack = getAudioTrack(env, thiz);
+
+    if (lpTrack == NULL) {
+        jniThrowException(env, "java/lang/IllegalStateException",
+            "Unable to retrieve AudioTrack pointer for getUnderrunCount()");
+        return (jint)AUDIO_JAVA_ERROR;
+    }
+    return (jint)lpTrack->getUnderrunCount();
+}
 
 // ----------------------------------------------------------------------------
 static jint android_media_AudioTrack_get_timestamp(JNIEnv *env,  jobject thiz, jlongArray jTimestamp) {
@@ -1094,6 +1105,7 @@ static const JNINativeMethod gMethods[] = {
     {"native_set_position",  "(I)I",     (void *)android_media_AudioTrack_set_position},
     {"native_get_position",  "()I",      (void *)android_media_AudioTrack_get_position},
     {"native_get_latency",   "()I",      (void *)android_media_AudioTrack_get_latency},
+    {"native_get_underrun_count", "()I",      (void *)android_media_AudioTrack_get_underrun_count},
     {"native_get_timestamp", "([J)I",    (void *)android_media_AudioTrack_get_timestamp},
     {"native_set_loop",      "(III)I",   (void *)android_media_AudioTrack_set_loop},
     {"native_reload_static", "()I",      (void *)android_media_AudioTrack_reload},

diff --git a/media/java/android/media/AudioTrack.java b/media/java/android/media/AudioTrack.java
index c110ce8..775d05b 100644 (file)
--- a/media/java/android/media/AudioTrack.java
+++ b/media/java/android/media/AudioTrack.java
@@ -42,7 +42,6 @@ import android.util.Log;
 
 import com.android.internal.app.IAppOpsService;
 
-
 /**
  * The AudioTrack class manages and plays a single audio resource for Java applications.
  * It allows streaming of PCM audio buffers to the audio sink for playback. This is
@@ -1132,6 +1131,25 @@ public class AudioTrack implements AudioRouting
     }
 
     /**
+     * Returns the number of underrun occurrences in the application-level write buffer
+     * since the AudioTrack was created.
+     * An underrun occurs if the application does not write audio
+     * data quickly enough, causing the buffer to underflow
+     * and a potential audio glitch or pop.
+     * Underruns are less likely when buffer sizes are large.
+     * <p> Though the "int" type is signed 32-bits, the value should be reinterpreted
+     * as if it is unsigned 32-bits.
+     * That is, the next position after 0x7FFFFFFF is (int) 0x80000000.
+     * This is a continuously advancing counter. It can wrap around to zero
+     * if there are too many underruns. If there were, for example, 68 underruns per
+     * second then the counter would wrap in 2 years.
+     * @hide
+     */
+    public int getUnderrunCount() {
+        return native_get_underrun_count();
+    }
+
+    /**
      *  Returns the output sample rate in Hz for the specified stream type.
      */
     static public int getNativeOutputSampleRate(int streamType) {
@@ -2722,6 +2740,8 @@ public class AudioTrack implements AudioRouting
 
     private native final int native_get_latency();
 
+    private native final int native_get_underrun_count();
+
     // longArray must be a non-null array of length >= 2
     // [0] is assigned the frame position
     // [1] is assigned the time in CLOCK_MONOTONIC nanoseconds