API CHANGE: Change the data callback in preparation for full-duplex.

This removes the two separate callbacks for sending and receiving data
to/from the device to a unified callback that's used for both input and
output. The new callback takes a pointer to both an input and output
buffer. When the device is opened in playback mode the input pointer
will be set to null. Likewise the output pointer will be set to null
for capture devices. Both input and output pointers will be non-null
for full-duplex devices.

examples/simple_capture.c

@@ -12,7 +12,7 @@ mal_uint32 capturedSampleCount = 0;
 mal_int16* pCapturedSamples = NULL;
 mal_uint32 playbackSample = 0;
 
-void on_recv_frames(mal_device* pDevice, mal_uint32 frameCount, const void* pSamples)
+void on_recv_frames(mal_device* pDevice, const void* pInput, void* pOutput, mal_uint32 frameCount)
 {
     mal_uint32 sampleCount = frameCount * pDevice->channels;
 
@@ -22,13 +22,15 @@ void on_recv_frames(mal_device* pDevice, mal_uint32 frameCount, const void* pSam
         return;
     }
 
-    memcpy(pNewCapturedSamples + capturedSampleCount, pSamples, sampleCount * sizeof(mal_int16));
+    memcpy(pNewCapturedSamples + capturedSampleCount, pInput, sampleCount * sizeof(mal_int16));
 
     pCapturedSamples = pNewCapturedSamples;
     capturedSampleCount = newCapturedSampleCount;
+
+    (void)pOutput;
 }
 
-mal_uint32 on_send_frames(mal_device* pDevice, mal_uint32 frameCount, void* pSamples)
+void on_send_frames(mal_device* pDevice, const void* pInput, void* pOutput, mal_uint32 frameCount)
 {
     mal_uint32 samplesToRead = frameCount * pDevice->channels;
     if (samplesToRead > capturedSampleCount-playbackSample) {
@@ -36,26 +38,27 @@ mal_uint32 on_send_frames(mal_device* pDevice, mal_uint32 frameCount, void* pSam
     }
 
     if (samplesToRead == 0) {
-        return 0;
+        return;
     }
 
-    memcpy(pSamples, pCapturedSamples + playbackSample, samplesToRead * sizeof(mal_int16));
+    memcpy(pOutput, pCapturedSamples + playbackSample, samplesToRead * sizeof(mal_int16));
     playbackSample += samplesToRead;
 
-    return samplesToRead / pDevice->channels;
+    (void)pInput;
 }
 
 int main()
 {
+    mal_device_config config;
+
     mal_context context;
     if (mal_context_init(NULL, 0, NULL, &context) != MAL_SUCCESS) {
         printf("Failed to initialize context.");
         return -1;
     }
 
-    mal_device_config config = mal_device_config_init(mal_format_s16, 2, 48000, on_recv_frames, on_send_frames, NULL);
-
     printf("Recording...\n");
+    config = mal_device_config_init(mal_format_s16, 2, 48000, on_recv_frames, NULL);
     mal_device captureDevice;
     if (mal_device_init(&context, mal_device_type_capture, NULL, &config, &captureDevice) != MAL_SUCCESS) {
         mal_context_uninit(&context);
@@ -78,6 +81,7 @@ int main()
 
 
     printf("Playing...\n");
+    config = mal_device_config_init(mal_format_s16, 2, 48000, on_send_frames, NULL);
     mal_device playbackDevice;
     if (mal_device_init(&context, mal_device_type_playback, NULL, &config, &playbackDevice) != MAL_SUCCESS) {
         mal_context_uninit(&context);

examples/simple_playback.c

@@ -11,14 +11,16 @@
 #include <stdio.h>
 
 // This is the function that's used for sending more data to the device for playback.
-mal_uint32 on_send_frames_to_device(mal_device* pDevice, mal_uint32 frameCount, void* pSamples)
+void on_send_frames_to_device(mal_device* pDevice, const void* pInput, void* pOutput, mal_uint32 frameCount)
 {
     mal_decoder* pDecoder = (mal_decoder*)pDevice->pUserData;
     if (pDecoder == NULL) {
-        return 0;
+        return;
     }
 
-    return (mal_uint32)mal_decoder_read_pcm_frames(pDecoder, frameCount, pSamples);
+    mal_decoder_read_pcm_frames(pDecoder, frameCount, pOutput);
+
+    (void)pInput;
 }
 
 int main(int argc, char** argv)
@@ -34,7 +36,7 @@ int main(int argc, char** argv)
         return -2;
     }
 
-    mal_device_config config = mal_device_config_init_playback(
+    mal_device_config config = mal_device_config_init(
         decoder.outputFormat,
         decoder.outputChannels,
         decoder.outputSampleRate,

tests/mal_dithering.c

@@ -30,16 +30,18 @@ mal_uint32 on_convert_samples_out(mal_format_converter* pConverter, mal_uint32 f
     return (mal_uint32)mal_format_converter_read(pConverterIn, frameCount, pFrames, NULL);
 }
 
-mal_uint32 on_send_to_device__original(mal_device* pDevice, mal_uint32 frameCount, void* pFrames)
+void on_send_to_device__original(mal_device* pDevice, const void* pInput, void* pOutput, mal_uint32 frameCount)
 {
-    (void)pDevice;
     mal_assert(pDevice->format == mal_format_f32);
     mal_assert(pDevice->channels == 1);
 
-    return (mal_uint32)mal_sine_wave_read_f32(&sineWave, frameCount, (float*)pFrames);
+    mal_sine_wave_read_f32(&sineWave, frameCount, (float*)pOutput);
+
+    (void)pDevice;
+    (void)pInput;
 }
 
-mal_uint32 on_send_to_device__dithered(mal_device* pDevice, mal_uint32 frameCount, void* pFrames)
+void on_send_to_device__dithered(mal_device* pDevice, const void* pInput, void* pOutput, mal_uint32 frameCount)
 {
     mal_assert(pDevice->channels == 1);
 
@@ -47,12 +49,14 @@ mal_uint32 on_send_to_device__dithered(mal_device* pDevice, mal_uint32 frameCoun
     mal_assert(pConverter != NULL);
     mal_assert(pDevice->format == pConverter->config.formatOut);
 
-    return (mal_uint32)mal_format_converter_read(pConverter, frameCount, pFrames, NULL);
+    mal_format_converter_read(pConverter, frameCount, pOutput, NULL);
+
+    (void)pInput;
 }
 
 int do_dithering_test()
 {
-    mal_device_config config = mal_device_config_init_playback(mal_format_f32, 1, 0, on_send_to_device__original, NULL);
+    mal_device_config config = mal_device_config_init(mal_format_f32, 1, 0, on_send_to_device__original, NULL);
     mal_device device;
     mal_result result;
 
@@ -102,7 +106,7 @@ int do_dithering_test()
         return -3;
     }
 
-    config = mal_device_config_init_playback(converterOutConfig.formatOut, 1, 0, on_send_to_device__dithered, &converterOut);
+    config = mal_device_config_init(converterOutConfig.formatOut, 1, 0, on_send_to_device__dithered, &converterOut);
 
     result = mal_device_init(NULL, mal_device_type_playback, NULL, &config, &device);
     if (result != MAL_SUCCESS) {

tests/mal_stop.c

+#include <stdio.h>
+
+#define MINI_AL_IMPLEMENTATION
+#include "../mini_al.h"
+
+mal_sine_wave sineWave;
+mal_uint32 framesWritten;
+mal_event stopEvent;
+mal_bool32 isInitialRun = MAL_TRUE;
+
+void on_stop(mal_device* pDevice)
+{
+    (void)pDevice;
+    printf("STOPPED\n");
+}
+
+void data_callback(mal_device* pDevice, const void* pInput, void* pOutput, mal_uint32 frameCount)
+{
+    (void)pInput;   /* Not used yet. */
+
+    /* It's important to initialize the buffer with silence to ensure exactly a second worth of data is actually output to the speakers. */
+    mal_zero_memory(pOutput, frameCount * mal_get_bytes_per_frame(pDevice->format, pDevice->channels));
+
+    /* Output exactly one second of data. Pad the end with silence. */
+    mal_uint32 framesRemaining = pDevice->sampleRate - framesWritten;
+    mal_uint32 framesToProcess = frameCount;
+    if (framesToProcess > framesRemaining && isInitialRun) {
+        framesToProcess = framesRemaining;
+    }
+
+    mal_sine_wave_read_f32_ex(&sineWave, framesToProcess, pDevice->channels, mal_stream_layout_interleaved, (float**)&pOutput);
+    if (isInitialRun) {
+        framesWritten += framesToProcess;
+    }
+
+    mal_assert(framesWritten <= pDevice->sampleRate);
+    if (framesWritten >= pDevice->sampleRate) {
+        if (isInitialRun) {
+            printf("STOPPING [AUDIO THREAD]...\n");
+            mal_event_signal(&stopEvent);
+            isInitialRun = MAL_FALSE;
+        }
+    }
+}
+
+int main(int argc, char** argv)
+{
+    mal_result result;
+
+    (void)argc;
+    (void)argv;
+
+    mal_backend backend = mal_backend_wasapi;
+
+    mal_sine_wave_init(0.25, 400, 44100, &sineWave);
+
+    mal_device_config config = mal_device_config_init_default(data_callback, NULL);
+    config.format = mal_format_f32;
+    config.channels = 2;
+    config.sampleRate = 44100;
+    config.onStopCallback = on_stop;
+    config.bufferSizeInFrames = 16384*4;
+
+    mal_device device;
+    result = mal_device_init_ex(&backend, 1, NULL, mal_device_type_playback, NULL, &config, &device);
+    if (result != MAL_SUCCESS) {
+        printf("Failed to initialize device.\n");
+        return result;
+    }
+
+    result = mal_event_init(device.pContext, &stopEvent);
+    if (result != MAL_SUCCESS) {
+        printf("Failed to initialize stop event.\n");
+        return result;
+    }
+
+    mal_device_start(&device);
+
+    /* We wait for the stop event, stop the device, then ask the user to press any key to restart. This checks that the device can restart after stopping. */
+    mal_event_wait(&stopEvent);
+
+    printf("STOPPING [MAIN THREAD]...\n");
+    mal_device_stop(&device);
+
+    printf("Press Enter to restart...\n");
+    getchar();
+
+    result = mal_device_start(&device);
+    if (result != MAL_SUCCESS) {
+        printf("Failed to restart the device.\n");
+        mal_device_uninit(&device);
+        return -1;
+    }
+
+    printf("Press Enter to quit...\n");
+    getchar();
+
+    mal_device_uninit(&device);
+    return 0;
+}
\ No newline at end of file

tests/mal_test_0.c

@@ -2232,18 +2232,16 @@ typedef struct
     mal_event endOfPlaybackEvent;
 } playback_test_callback_data;
 
-mal_uint32 on_send__playback_test(mal_device* pDevice, mal_uint32 frameCount, void* pFrames)
+void on_send__playback_test(mal_device* pDevice, const void* pInput, void* pOutput, mal_uint32 frameCount)
 {
     playback_test_callback_data* pData = (playback_test_callback_data*)pDevice->pUserData;
     mal_assert(pData != NULL);
 
 #if !defined(__EMSCRIPTEN__)
-    mal_uint64 framesRead = mal_decoder_read_pcm_frames(pData->pDecoder, frameCount, pFrames);
+    mal_uint64 framesRead = mal_decoder_read_pcm_frames(pData->pDecoder, frameCount, pOutput);
     if (framesRead == 0) {
         mal_event_signal(&pData->endOfPlaybackEvent);
     }
-
-    return (mal_uint32)framesRead;
 #else
     if (pDevice->format == mal_format_f32) {
         for (mal_uint32 iFrame = 0; iFrame < frameCount; ++iFrame) {
@@ -2254,10 +2252,6 @@ mal_uint32 on_send__playback_test(mal_device* pDevice, mal_uint32 frameCount, vo
                 ((float*)pFrames)[iFrame*pDevice->channels + iChannel] = sample;
             }
         }
-
-        return frameCount;
-    } else {
-        return 0;
     }
 #endif
 }
@@ -2290,7 +2284,7 @@ int do_playback_test(mal_backend backend)
     printf("  Opening Device... ");
     {
         mal_context_config contextConfig = mal_context_config_init(on_log);
-        mal_device_config deviceConfig = mal_device_config_init_default_playback(on_send__playback_test, &callbackData);
+        mal_device_config deviceConfig = mal_device_config_init_default(on_send__playback_test, &callbackData);
         deviceConfig.onStopCallback = on_stop__playback_test;
 
     #if defined(__EMSCRIPTEN__)

tests/mal_test_0.vcxproj

@@ -270,7 +270,22 @@
       <ExcludedFromBuild Condition="'$(Configuration)|$(Platform)'=='Debug|x64'">true</ExcludedFromBuild>
       <ExcludedFromBuild Condition="'$(Configuration)|$(Platform)'=='Release|x64'">true</ExcludedFromBuild>
     </ClCompile>
-    <ClCompile Include="..\examples\simple_enumeration.c" />
+    <ClCompile Include="..\examples\simple_capture.c">
+      <ExcludedFromBuild Condition="'$(Configuration)|$(Platform)'=='Debug|Win32'">true</ExcludedFromBuild>
+      <ExcludedFromBuild Condition="'$(Configuration)|$(Platform)'=='Release|Win32'">true</ExcludedFromBuild>
+      <ExcludedFromBuild Condition="'$(Configuration)|$(Platform)'=='Debug|ARM'">true</ExcludedFromBuild>
+      <ExcludedFromBuild Condition="'$(Configuration)|$(Platform)'=='Release|ARM'">true</ExcludedFromBuild>
+      <ExcludedFromBuild Condition="'$(Configuration)|$(Platform)'=='Debug|x64'">true</ExcludedFromBuild>
+      <ExcludedFromBuild Condition="'$(Configuration)|$(Platform)'=='Release|x64'">true</ExcludedFromBuild>
+    </ClCompile>
+    <ClCompile Include="..\examples\simple_enumeration.c">
+      <ExcludedFromBuild Condition="'$(Configuration)|$(Platform)'=='Debug|Win32'">true</ExcludedFromBuild>
+      <ExcludedFromBuild Condition="'$(Configuration)|$(Platform)'=='Release|Win32'">true</ExcludedFromBuild>
+      <ExcludedFromBuild Condition="'$(Configuration)|$(Platform)'=='Debug|ARM'">true</ExcludedFromBuild>
+      <ExcludedFromBuild Condition="'$(Configuration)|$(Platform)'=='Release|ARM'">true</ExcludedFromBuild>
+      <ExcludedFromBuild Condition="'$(Configuration)|$(Platform)'=='Debug|x64'">true</ExcludedFromBuild>
+      <ExcludedFromBuild Condition="'$(Configuration)|$(Platform)'=='Release|x64'">true</ExcludedFromBuild>
+    </ClCompile>
     <ClCompile Include="..\examples\simple_playback.c">
       <ExcludedFromBuild Condition="'$(Configuration)|$(Platform)'=='Debug|Win32'">true</ExcludedFromBuild>
       <ExcludedFromBuild Condition="'$(Configuration)|$(Platform)'=='Release|Win32'">true</ExcludedFromBuild>
@@ -303,6 +318,14 @@
       <ExcludedFromBuild Condition="'$(Configuration)|$(Platform)'=='Debug|x64'">true</ExcludedFromBuild>
       <ExcludedFromBuild Condition="'$(Configuration)|$(Platform)'=='Release|x64'">true</ExcludedFromBuild>
     </ClCompile>
+    <ClCompile Include="mal_duplex.c">
+      <ExcludedFromBuild Condition="'$(Configuration)|$(Platform)'=='Debug|Win32'">true</ExcludedFromBuild>
+      <ExcludedFromBuild Condition="'$(Configuration)|$(Platform)'=='Release|Win32'">true</ExcludedFromBuild>
+      <ExcludedFromBuild Condition="'$(Configuration)|$(Platform)'=='Debug|ARM'">true</ExcludedFromBuild>
+      <ExcludedFromBuild Condition="'$(Configuration)|$(Platform)'=='Release|ARM'">true</ExcludedFromBuild>
+      <ExcludedFromBuild Condition="'$(Configuration)|$(Platform)'=='Debug|x64'">true</ExcludedFromBuild>
+      <ExcludedFromBuild Condition="'$(Configuration)|$(Platform)'=='Release|x64'">true</ExcludedFromBuild>
+    </ClCompile>
     <ClCompile Include="mal_no_device_io.c">
       <ExcludedFromBuild Condition="'$(Configuration)|$(Platform)'=='Debug|Win32'">true</ExcludedFromBuild>
       <ExcludedFromBuild Condition="'$(Configuration)|$(Platform)'=='Release|Win32'">true</ExcludedFromBuild>
@@ -327,6 +350,7 @@
       <ExcludedFromBuild Condition="'$(Configuration)|$(Platform)'=='Debug|x64'">true</ExcludedFromBuild>
       <ExcludedFromBuild Condition="'$(Configuration)|$(Platform)'=='Release|x64'">true</ExcludedFromBuild>
     </ClCompile>
+    <ClCompile Include="mal_stop.c" />
     <ClCompile Include="mal_test_0.c">
       <ExcludedFromBuild Condition="'$(Configuration)|$(Platform)'=='Debug|Win32'">true</ExcludedFromBuild>
       <ExcludedFromBuild Condition="'$(Configuration)|$(Platform)'=='Debug|ARM'">true</ExcludedFromBuild>

tests/mal_test_0.vcxproj.filters

@@ -51,6 +51,15 @@
     <ClCompile Include="..\examples\simple_enumeration.c">
       <Filter>Source Files</Filter>
     </ClCompile>
+    <ClCompile Include="mal_duplex.c">
+      <Filter>Source Files</Filter>
+    </ClCompile>
+    <ClCompile Include="mal_stop.c">
+      <Filter>Source Files</Filter>
+    </ClCompile>
+    <ClCompile Include="..\examples\simple_capture.c">
+      <Filter>Source Files</Filter>
+    </ClCompile>
   </ItemGroup>
   <ItemGroup>
     <ClInclude Include="..\mini_al.h">