Refactor common_audio/vad: Create now returns the handle directly instead of an error code

Changed the WebRtcVad_Create() function to the more conventional format of returning the handle directly instead of an error code to take care of.
In addition NULL was changed to nullptr in the files where it applied.

Affected components:
* AGC
* VAD
* NetEQ

BUG=441, 3347
TESTED=locally on Linux and trybots
R=kwiberg@webrtc.org

Review URL: https://webrtc-codereview.appspot.com/51919004

Cr-Commit-Position: refs/heads/master@{#9291}

webrtc/common_audio/vad/include/webrtc_vad.h

@@ -25,11 +25,8 @@ extern "C" {
 #endif
 
 // Creates an instance to the VAD structure.
-//
-// - handle [o] : Pointer to the VAD instance that should be created.
-//
-// returns      : 0 - (OK), -1 - (Error)
-int WebRtcVad_Create(VadInst** handle);
+// Returns a null pointer if create was unsuccessful.
+VadInst* WebRtcVad_Create();
 
 // Frees the dynamic memory of a specified VAD instance.
 //

webrtc/common_audio/vad/vad.cc

@@ -15,7 +15,8 @@
 namespace webrtc {
 
 Vad::Vad(enum Aggressiveness mode) {
-  CHECK_EQ(WebRtcVad_Create(&handle_), 0);
+  handle_ = WebRtcVad_Create();
+  CHECK(handle_);
   CHECK_EQ(WebRtcVad_Init(handle_), 0);
   CHECK_EQ(WebRtcVad_set_mode(handle_, mode), 0);
 }

webrtc/common_audio/vad/vad_unittest.cc

@@ -14,6 +14,7 @@
 
 #include "testing/gtest/include/gtest/gtest.h"
 
+#include "webrtc/base/checks.h"
 #include "webrtc/common_audio/signal_processing/include/signal_processing_library.h"
 #include "webrtc/common_audio/vad/include/webrtc_vad.h"
 #include "webrtc/typedefs.h"
@@ -57,7 +58,7 @@ TEST_F(VadTest, ApiTest) {
   // This API test runs through the APIs for all possible valid and invalid
   // combinations.
 
-  VadInst* handle = NULL;
+  VadInst* handle = WebRtcVad_Create();
   int16_t zeros[kMaxFrameLength] = { 0 };
 
   // Construct a speech signal that will trigger the VAD in all modes. It is
@@ -67,14 +68,14 @@ TEST_F(VadTest, ApiTest) {
     speech[i] = (i * i);
   }
 
-  // NULL instance tests
-  EXPECT_EQ(-1, WebRtcVad_Create(NULL));
-  EXPECT_EQ(-1, WebRtcVad_Init(NULL));
-  EXPECT_EQ(-1, WebRtcVad_set_mode(NULL, kModes[0]));
-  EXPECT_EQ(-1, WebRtcVad_Process(NULL, kRates[0], speech, kFrameLengths[0]));
+  // nullptr instance tests
+  EXPECT_EQ(-1, WebRtcVad_Init(nullptr));
+  EXPECT_EQ(-1, WebRtcVad_set_mode(nullptr, kModes[0]));
+  EXPECT_EQ(-1,
+            WebRtcVad_Process(nullptr, kRates[0], speech, kFrameLengths[0]));
 
   // WebRtcVad_Create()
-  ASSERT_EQ(0, WebRtcVad_Create(&handle));
+  CHECK(handle);
 
   // Not initialized tests
   EXPECT_EQ(-1, WebRtcVad_Process(handle, kRates[0], speech, kFrameLengths[0]));
@@ -93,8 +94,9 @@ TEST_F(VadTest, ApiTest) {
                                                          kModesSize) + 1));
 
   // WebRtcVad_Process() tests
-  // NULL speech pointer
-  EXPECT_EQ(-1, WebRtcVad_Process(handle, kRates[0], NULL, kFrameLengths[0]));
+  // nullptr as speech pointer
+  EXPECT_EQ(-1,
+            WebRtcVad_Process(handle, kRates[0], nullptr, kFrameLengths[0]));
   // Invalid sampling rate
   EXPECT_EQ(-1, WebRtcVad_Process(handle, 9999, speech, kFrameLengths[0]));
   // All zeros as input should work

webrtc/common_audio/vad/webrtc_vad.c

@@ -22,26 +22,16 @@ static const int kValidRates[] = { 8000, 16000, 32000, 48000 };
 static const size_t kRatesSize = sizeof(kValidRates) / sizeof(*kValidRates);
 static const int kMaxFrameLengthMs = 30;
 
-int WebRtcVad_Create(VadInst** handle) {
-  VadInstT* self = NULL;
-
-  if (handle == NULL) {
-    return -1;
-  }
-
-  *handle = NULL;
-  self = (VadInstT*) malloc(sizeof(VadInstT));
-  *handle = (VadInst*) self;
-
+VadInst* WebRtcVad_Create() {
+  VadInstT* self = (VadInstT*)malloc(sizeof(VadInstT));
   if (self == NULL) {
-    return -1;
+    return NULL;
   }
 
   WebRtcSpl_Init();
-
   self->init_flag = 0;
 
-  return 0;
+  return (VadInst*)self;
 }
 
 void WebRtcVad_Free(VadInst* handle) {

webrtc/modules/audio_coding/neteq/post_decode_vad.cc

@@ -20,7 +20,8 @@ PostDecodeVad::~PostDecodeVad() {
 void PostDecodeVad::Enable() {
   if (!vad_instance_) {
     // Create the instance.
-    if (WebRtcVad_Create(&vad_instance_) != 0) {
+    vad_instance_ = WebRtcVad_Create();
+    if (vad_instance_ == nullptr) {
       // Failed to create instance.
       Disable();
       return;

webrtc/modules/audio_coding/neteq/test/RTPencode.cc

@@ -908,8 +908,8 @@ int NetEQTest_init_coders(webrtc::NetEqDecoder coder, int enc_frameSize, int bit
 	
     for (int k = 0; k < numChannels; k++) 
     {
-        ok=WebRtcVad_Create(&VAD_inst[k]);
-        if (ok!=0) {
+        VAD_inst[k] = WebRtcVad_Create();
+        if (!VAD_inst[k]) {
             printf("Error: Couldn't allocate memory for VAD instance\n");
             exit(0);
         }

webrtc/modules/audio_processing/agc/standalone_vad.cc

@@ -31,15 +31,15 @@ StandaloneVad::~StandaloneVad() {
 }
 
 StandaloneVad* StandaloneVad::Create() {
-  VadInst* vad = NULL;
-  if (WebRtcVad_Create(&vad) < 0)
-    return NULL;
+  VadInst* vad = WebRtcVad_Create();
+  if (!vad)
+    return nullptr;
 
   int err = WebRtcVad_Init(vad);
   err |= WebRtcVad_set_mode(vad, kDefaultStandaloneVadMode);
   if (err != 0) {
     WebRtcVad_Free(vad);
-    return NULL;
+    return nullptr;
   }
   return new StandaloneVad(vad);
 }

webrtc/modules/audio_processing/voice_detection_impl.cc

@@ -148,14 +148,7 @@ int VoiceDetectionImpl::Initialize() {
 }
 
 void* VoiceDetectionImpl::CreateHandle() const {
-  Handle* handle = NULL;
-  if (WebRtcVad_Create(&handle) != apm_->kNoError) {
-    handle = NULL;
-  } else {
-    assert(handle != NULL);
-  }
-
-  return handle;
+  return WebRtcVad_Create();
 }
 
 void VoiceDetectionImpl::DestroyHandle(void* handle) const {