aaudio: AAudio_setMMapPolicy()

Controls whether MMAP data path is used NEVER, AUTO or ALWAYS
For testing only. To improve code coverage in CTS.

Bug: 38268547
Test: write_sine.cpp
Change-Id: Iad97876fb6f1d0c653262161b7b5519d83d16ac5
Signed-off-by: Phil Burk <philburk@google.com>
diff --git a/media/libaaudio/examples/write_sine/src/write_sine.cpp b/media/libaaudio/examples/write_sine/src/write_sine.cpp
index 27c6128..4cf5ef5 100644
--- a/media/libaaudio/examples/write_sine/src/write_sine.cpp
+++ b/media/libaaudio/examples/write_sine/src/write_sine.cpp
@@ -20,15 +20,22 @@
 #include <stdlib.h>
 #include <math.h>
 #include <aaudio/AAudio.h>
+#include <aaudio/AAudioTesting.h>
 #include "AAudioExampleUtils.h"
 #include "AAudioSimplePlayer.h"
 
 #define SAMPLE_RATE           48000
 #define NUM_SECONDS           20
 
-#define REQUESTED_FORMAT  AAUDIO_FORMAT_PCM_I16
-#define REQUESTED_SHARING_MODE  AAUDIO_SHARING_MODE_SHARED
-//#define REQUESTED_SHARING_MODE  AAUDIO_SHARING_MODE_EXCLUSIVE
+#define MMAP_POLICY              AAUDIO_UNSPECIFIED
+//#define MMAP_POLICY              AAUDIO_POLICY_NEVER
+//#define MMAP_POLICY              AAUDIO_POLICY_AUTO
+//#define MMAP_POLICY              AAUDIO_POLICY_ALWAYS
+
+#define REQUESTED_FORMAT         AAUDIO_FORMAT_PCM_I16
+
+#define REQUESTED_SHARING_MODE   AAUDIO_SHARING_MODE_SHARED
+//#define REQUESTED_SHARING_MODE   AAUDIO_SHARING_MODE_EXCLUSIVE
 
 
 int main(int argc, char **argv)
@@ -64,6 +71,9 @@
 
     printf("%s - Play a sine wave using AAudio\n", argv[0]);
 
+    AAudio_setMMapPolicy(MMAP_POLICY);
+    printf("requested MMapPolicy = %d\n", AAudio_getMMapPolicy());
+
     player.setSharingMode(REQUESTED_SHARING_MODE);
 
     result = player.open(requestedChannelCount, requestedSampleRate, requestedDataFormat,
@@ -98,7 +108,7 @@
     // This is the number of frames that are read in one chunk by a DMA controller
     // or a DSP or a mixer.
     framesPerBurst = AAudioStream_getFramesPerBurst(aaudioStream);
-    printf("Buffer: bufferSize = %d\n", AAudioStream_getBufferSizeInFrames(aaudioStream));
+    printf("Buffer: bufferSize     = %d\n", AAudioStream_getBufferSizeInFrames(aaudioStream));
     bufferCapacity = AAudioStream_getBufferCapacityInFrames(aaudioStream);
     printf("Buffer: bufferCapacity = %d, remainder = %d\n",
            bufferCapacity, bufferCapacity % framesPerBurst);
@@ -112,11 +122,12 @@
     printf("Buffer: framesPerBurst = %d\n",framesPerBurst);
     printf("Buffer: framesPerWrite = %d\n",framesPerWrite);
 
-    actualDataFormat = AAudioStream_getFormat(aaudioStream);
-    printf("DataFormat: requested = %d, actual = %d\n", REQUESTED_FORMAT, actualDataFormat);
-    // TODO handle other data formats
+    printf("PerformanceMode        = %d\n", AAudioStream_getPerformanceMode(aaudioStream));
+    printf("is MMAP used?          = %s\n", AAudioStream_isMMapUsed(aaudioStream) ? "yes" : "no");
 
-    printf("PerformanceMode: %d\n", AAudioStream_getPerformanceMode(aaudioStream));
+    actualDataFormat = AAudioStream_getFormat(aaudioStream);
+    printf("DataFormat: requested  = %d, actual = %d\n", REQUESTED_FORMAT, actualDataFormat);
+    // TODO handle other data formats
 
     // Allocate a buffer for the audio data.
     if (actualDataFormat == AAUDIO_FORMAT_PCM_FLOAT) {
diff --git a/media/libaaudio/include/aaudio/AAudioTesting.h b/media/libaaudio/include/aaudio/AAudioTesting.h
new file mode 100644
index 0000000..02ec411
--- /dev/null
+++ b/media/libaaudio/include/aaudio/AAudioTesting.h
@@ -0,0 +1,94 @@
+/*
+ * Copyright (C) 2017 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+/**
+ * This is test support for AAudio.
+ */
+#ifndef AAUDIO_AAUDIO_TESTING_H
+#define AAUDIO_AAUDIO_TESTING_H
+
+#include <aaudio/AAudio.h>
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/************************************************************************************
+ * The definitions below are only for testing. Do not use them in an application.
+ * They may change or be removed at any time.
+ ************************************************************************************/
+
+enum {
+    /**
+     * Related feature is disabled and never used.
+     */
+    AAUDIO_POLICY_NEVER = 1,
+
+    /**
+     * If related feature works then use it. Otherwise fall back to something else.
+     */
+     AAUDIO_POLICY_AUTO,
+
+    /**
+     * Related feature must be used. If not available then fail.
+     */
+    AAUDIO_POLICY_ALWAYS
+};
+typedef int32_t aaudio_policy_t;
+
+/**
+ * Control whether AAudioStreamBuilder_openStream() will use the new MMAP data path
+ * or the older "Legacy" data path.
+ *
+ * This will only affect the current process.
+ *
+ * If unspecified then the policy will be based on system properties or configuration.
+ *
+ * @note This is only for testing. Do not use this in an application.
+ * It may change or be removed at any time.
+ *
+ * @param policy AAUDIO_UNSPECIFIED, AAUDIO_POLICY_NEVER, AAUDIO_POLICY_AUTO, or AAUDIO_POLICY_ALWAYS
+ * @return AAUDIO_OK or a negative error
+ */
+AAUDIO_API aaudio_result_t AAudio_setMMapPolicy(aaudio_policy_t policy);
+
+/**
+ * Get the current MMAP policy set by AAudio_setMMapPolicy().
+ *
+ * @note This is only for testing. Do not use this in an application.
+ * It may change or be removed at any time.
+ *
+ * @return current policy
+ */
+AAUDIO_API aaudio_policy_t AAudio_getMMapPolicy();
+
+/**
+ * Return true if the stream uses the MMAP data path versus the legacy path.
+ *
+ * @note This is only for testing. Do not use this in an application.
+ * It may change or be removed at any time.
+ *
+ * @return true if the stream uses ther MMAP data path
+ */
+AAUDIO_API bool AAudioStream_isMMapUsed(AAudioStream* stream);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif //AAUDIO_AAUDIO_TESTING_H
+
+/** @} */
diff --git a/media/libaaudio/libaaudio.map.txt b/media/libaaudio/libaaudio.map.txt
index 8f74800..2ba5250 100644
--- a/media/libaaudio/libaaudio.map.txt
+++ b/media/libaaudio/libaaudio.map.txt
@@ -3,6 +3,8 @@
     AAudio_convertResultToText;
     AAudio_convertStreamStateToText;
     AAudio_createStreamBuilder;
+    AAudio_getMMapPolicy;
+    AAudio_setMMapPolicy;
     AAudioStreamBuilder_setPerformanceMode;
     AAudioStreamBuilder_setDeviceId;
     AAudioStreamBuilder_setDataCallback;
@@ -43,6 +45,7 @@
     AAudioStream_getFramesWritten;
     AAudioStream_getFramesRead;
     AAudioStream_getTimestamp;
+    AAudioStream_isMMapUsed;
   local:
     *;
 };
diff --git a/media/libaaudio/src/core/AAudioAudio.cpp b/media/libaaudio/src/core/AAudioAudio.cpp
index c644ee5..d22ad32 100644
--- a/media/libaaudio/src/core/AAudioAudio.cpp
+++ b/media/libaaudio/src/core/AAudioAudio.cpp
@@ -22,6 +22,7 @@
 #include <pthread.h>
 
 #include <aaudio/AAudio.h>
+#include <aaudio/AAudioTesting.h>
 
 #include "AudioStreamBuilder.h"
 #include "AudioStream.h"
@@ -94,6 +95,13 @@
 
 #undef AAUDIO_CASE_ENUM
 
+
+/******************************************
+ * Static globals.
+ */
+static aaudio_policy_t s_MMapPolicy = AAUDIO_UNSPECIFIED;
+
+
 static AudioStream *convertAAudioStreamToAudioStream(AAudioStream* stream)
 {
     return (AudioStream*) stream;
@@ -454,3 +462,29 @@
 
     return audioStream->getTimestamp(clockid, framePosition, timeNanoseconds);
 }
+
+AAUDIO_API aaudio_policy_t AAudio_getMMapPolicy() {
+    return s_MMapPolicy;
+}
+
+AAUDIO_API aaudio_result_t AAudio_setMMapPolicy(aaudio_policy_t policy) {
+    aaudio_result_t result = AAUDIO_OK;
+    switch(policy) {
+        case AAUDIO_UNSPECIFIED:
+        case AAUDIO_POLICY_NEVER:
+        case AAUDIO_POLICY_AUTO:
+        case AAUDIO_POLICY_ALWAYS:
+            s_MMapPolicy = policy;
+            break;
+        default:
+            result = AAUDIO_ERROR_ILLEGAL_ARGUMENT;
+            break;
+    }
+    return result;
+}
+
+AAUDIO_API bool AAudioStream_isMMapUsed(AAudioStream* stream)
+{
+    AudioStream *audioStream = convertAAudioStreamToAudioStream(stream);
+    return audioStream->isMMap();
+}
diff --git a/media/libaaudio/src/core/AudioStreamBuilder.cpp b/media/libaaudio/src/core/AudioStreamBuilder.cpp
index e6d5d74..4262f27 100644
--- a/media/libaaudio/src/core/AudioStreamBuilder.cpp
+++ b/media/libaaudio/src/core/AudioStreamBuilder.cpp
@@ -22,6 +22,7 @@
 #include <stdint.h>
 
 #include <aaudio/AAudio.h>
+#include <aaudio/AAudioTesting.h>
 
 #include "binding/AAudioBinderClient.h"
 #include "client/AudioStreamInternalCapture.h"
@@ -33,6 +34,9 @@
 
 using namespace aaudio;
 
+#define AAUDIO_MMAP_POLICY_DEFAULT             AAUDIO_POLICY_NEVER
+#define AAUDIO_MMAP_EXCLUSIVE_POLICY_DEFAULT   AAUDIO_POLICY_NEVER
+
 /*
  * AudioStreamBuilder
  */
@@ -76,25 +80,41 @@
     return result;
 }
 
-// Try to open using MMAP path if that is enabled.
-// Fall back to Legacy path is MMAP not available.
+// Try to open using MMAP path if that is allowed.
+// Fall back to Legacy path if MMAP not available.
+// Exact behavior is controlled by MMapPolicy.
 aaudio_result_t AudioStreamBuilder::build(AudioStream** streamPtr) {
     AudioStream *audioStream = nullptr;
     *streamPtr = nullptr;
 
-    int32_t mmapEnabled = AAudioProperty_getMMapEnabled();
-    int32_t mmapExclusiveEnabled = AAudioProperty_getMMapExclusiveEnabled();
+    // The API setting is the highest priority.
+    aaudio_policy_t mmapPolicy = AAudio_getMMapPolicy();
+    // If not specified then get from a system property.
+    if (mmapPolicy == AAUDIO_UNSPECIFIED) {
+        mmapPolicy = AAudioProperty_getMMapPolicy();
+    }
+    // If still not specified then use the default.
+    if (mmapPolicy == AAUDIO_UNSPECIFIED) {
+        mmapPolicy = AAUDIO_MMAP_POLICY_DEFAULT;
+    }
+
+    int32_t mapExclusivePolicy = AAudioProperty_getMMapExclusivePolicy();
+    if (mapExclusivePolicy == AAUDIO_UNSPECIFIED) {
+        mapExclusivePolicy = AAUDIO_MMAP_EXCLUSIVE_POLICY_DEFAULT;
+    }
+    ALOGD("AudioStreamBuilder(): mmapPolicy = %d, mapExclusivePolicy = %d",
+          mmapPolicy, mapExclusivePolicy);
 
     aaudio_sharing_mode_t sharingMode = getSharingMode();
     if ((sharingMode == AAUDIO_SHARING_MODE_EXCLUSIVE)
-        && (mmapExclusiveEnabled == AAUDIO_USE_NEVER)) {
+        && (mapExclusivePolicy == AAUDIO_POLICY_NEVER)) {
         ALOGW("AudioStreamBuilder(): EXCLUSIVE sharing mode not supported. Use SHARED.");
         sharingMode = AAUDIO_SHARING_MODE_SHARED;
         setSharingMode(sharingMode);
     }
 
-    bool allowMMap = mmapEnabled != AAUDIO_USE_NEVER;
-    bool allowLegacy = mmapEnabled != AAUDIO_USE_ALWAYS;
+    bool allowMMap = mmapPolicy != AAUDIO_POLICY_NEVER;
+    bool allowLegacy = mmapPolicy != AAUDIO_POLICY_ALWAYS;
 
     aaudio_result_t result = builder_createStream(getDirection(), sharingMode,
                                                   allowMMap, &audioStream);
diff --git a/media/libaaudio/src/utility/AAudioUtilities.cpp b/media/libaaudio/src/utility/AAudioUtilities.cpp
index 38ad59f..3fbcae9 100644
--- a/media/libaaudio/src/utility/AAudioUtilities.cpp
+++ b/media/libaaudio/src/utility/AAudioUtilities.cpp
@@ -24,7 +24,9 @@
 #include <utils/Errors.h>
 
 #include "aaudio/AAudio.h"
-#include "AAudioUtilities.h"
+#include <aaudio/AAudioTesting.h>
+
+#include "utility/AAudioUtilities.h"
 
 using namespace android;
 
@@ -329,9 +331,10 @@
                                               const char * caller) {
     int32_t prop = property_get_int32(propName, defaultValue);
     switch (prop) {
-        case AAUDIO_USE_NEVER:
-        case AAUDIO_USE_ALWAYS:
-        case AAUDIO_USE_AUTO:
+        case AAUDIO_UNSPECIFIED:
+        case AAUDIO_POLICY_NEVER:
+        case AAUDIO_POLICY_ALWAYS:
+        case AAUDIO_POLICY_AUTO:
             break;
         default:
             ALOGE("%s: invalid = %d", caller, prop);
@@ -341,14 +344,14 @@
     return prop;
 }
 
-int32_t AAudioProperty_getMMapEnabled() {
-    return AAudioProperty_getMMapProperty(AAUDIO_PROP_MMAP_ENABLED,
-                                          AAUDIO_USE_NEVER, __func__);
+int32_t AAudioProperty_getMMapPolicy() {
+    return AAudioProperty_getMMapProperty(AAUDIO_PROP_MMAP_POLICY,
+                                          AAUDIO_UNSPECIFIED, __func__);
 }
 
-int32_t AAudioProperty_getMMapExclusiveEnabled() {
-    return AAudioProperty_getMMapProperty(AAUDIO_PROP_MMAP_EXCLUSIVE_ENABLED,
-                                          AAUDIO_USE_NEVER, __func__);
+int32_t AAudioProperty_getMMapExclusivePolicy() {
+    return AAudioProperty_getMMapProperty(AAUDIO_PROP_MMAP_EXCLUSIVE_POLICY,
+                                          AAUDIO_UNSPECIFIED, __func__);
 }
 
 int32_t AAudioProperty_getMixerBursts() {
diff --git a/media/libaaudio/src/utility/AAudioUtilities.h b/media/libaaudio/src/utility/AAudioUtilities.h
index 7c383c7..7039ba2 100644
--- a/media/libaaudio/src/utility/AAudioUtilities.h
+++ b/media/libaaudio/src/utility/AAudioUtilities.h
@@ -173,30 +173,21 @@
 
 // Note that this code may be replaced by Settings or by some other system configuration tool.
 
-enum : int32_t {
-    // Related feature is disabled
-    AAUDIO_USE_NEVER = 0,
-    // If related feature works then use it. Otherwise fall back to something else.
-    AAUDIO_USE_AUTO = 1,
-    // Related feature must be used. If not available then fail.
-    AAUDIO_USE_ALWAYS = 2
-};
-
-#define AAUDIO_PROP_MMAP_ENABLED           "aaudio.mmap_enabled"
+#define AAUDIO_PROP_MMAP_POLICY           "aaudio.mmap_policy"
 
 /**
  * Read system property.
- * @return AAUDIO_USE_NEVER or AAUDIO_USE_AUTO or AAUDIO_USE_ALWAYS
+ * @return AAUDIO_UNSPECIFIED, AAUDIO_POLICY_NEVER or AAUDIO_POLICY_AUTO or AAUDIO_POLICY_ALWAYS
  */
-int32_t AAudioProperty_getMMapEnabled();
+int32_t AAudioProperty_getMMapPolicy();
 
-#define AAUDIO_PROP_MMAP_EXCLUSIVE_ENABLED "aaudio.mmap_exclusive_enabled"
+#define AAUDIO_PROP_MMAP_EXCLUSIVE_POLICY "aaudio.mmap_exclusive_policy"
 
 /**
  * Read system property.
- * @return AAUDIO_USE_NEVER or AAUDIO_USE_AUTO or AAUDIO_USE_ALWAYS
+ * @return AAUDIO_UNSPECIFIED, AAUDIO_POLICY_NEVER or AAUDIO_POLICY_AUTO or AAUDIO_POLICY_ALWAYS
  */
-int32_t AAudioProperty_getMMapExclusiveEnabled();
+int32_t AAudioProperty_getMMapExclusivePolicy();
 
 #define AAUDIO_PROP_MIXER_BURSTS           "aaudio.mixer_bursts"