Alc/android.c

   1 /**
   2  * OpenAL cross platform audio library
   3  * Copyright (C) 2010 by Chris Robinson
   4  * This library is free software; you can redistribute it and/or
   5  *  modify it under the terms of the GNU Library General Public
   6  *  License as published by the Free Software Foundation; either
   7  *  version 2 of the License, or (at your option) any later version.
   8  *
   9  * This library is distributed in the hope that it will be useful,
  10  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  12  *  Library General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU Library General Public
  15  *  License along with this library; if not, write to the
  16  *  Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  17  *  Boston, MA  02111-1307, USA.
  18  * Or go to http://www.gnu.org/copyleft/lgpl.html
  19  */
  20
  21 #include "config.h"
  22
  23 #include <stdlib.h>
  24 #include <jni.h>
  25 #include <pthread.h>
  26 #include "alMain.h"
  27 #include "AL/al.h"
  28 #include "AL/alc.h"
  29
  30 static const ALCchar android_device[] = "Android Default";
  31
  32 static JavaVM* javaVM = NULL;
  33
  34 static jclass cAudioTrack = NULL;
  35
  36 static jmethodID mAudioTrack;
  37 static jmethodID mGetMinBufferSize;
  38 static jmethodID mPlay;
  39 static jmethodID mStop;
  40 static jmethodID mRelease;
  41 static jmethodID mWrite;
  42
  43 jint JNI_OnLoad(JavaVM* vm, void* reserved)
  44 {
  45     javaVM = vm;
  46     return JNI_VERSION_1_2;
  47 }
  48
  49 static JNIEnv* GetEnv()
  50 {
  51     JNIEnv* env = NULL;
  52     if (javaVM) (*javaVM)->GetEnv(javaVM, (void**)&env, JNI_VERSION_1_2);
  53     return env;
  54 }
  55
  56 typedef struct
  57 {
  58     pthread_t thread;
  59     volatile int running;
  60 } AndroidData;
  61
  62 #define STREAM_MUSIC 3
  63 #define CHANNEL_CONFIGURATION_MONO 2
  64 #define CHANNEL_CONFIGURATION_STEREO 3
  65 #define ENCODING_PCM_8BIT 3
  66 #define ENCODING_PCM_16BIT 2
  67 #define MODE_STREAM 1
  68
  69 static void* thread_function(void* arg)
  70 {
  71     ALCdevice* device = (ALCdevice*)arg;
  72     AndroidData* data = (AndroidData*)device->ExtraData;
  73
  74     JNIEnv* env;
  75     (*javaVM)->AttachCurrentThread(javaVM, &env, NULL);
  76
  77     (*env)->PushLocalFrame(env, 2);
  78
  79     int sampleRateInHz = device->Frequency;
  80     int channelConfig = aluChannelsFromFormat(device->Format) == 1 ? CHANNEL_CONFIGURATION_MONO : CHANNEL_CONFIGURATION_STEREO;
  81     int audioFormat = aluBytesFromFormat(device->Format) == 1 ? ENCODING_PCM_8BIT : ENCODING_PCM_16BIT;
  82
  83     int bufferSizeInBytes = (*env)->CallStaticIntMethod(env, cAudioTrack,
  84         mGetMinBufferSize, sampleRateInHz, channelConfig, audioFormat);
  85
  86     int bufferSizeInSamples = bufferSizeInBytes / aluFrameSizeFromFormat(device->Format);
  87
  88     jobject track = (*env)->NewObject(env, cAudioTrack, mAudioTrack,
  89         STREAM_MUSIC, sampleRateInHz, channelConfig, audioFormat, device->NumUpdates * bufferSizeInBytes, MODE_STREAM);
  90
  91     (*env)->CallNonvirtualVoidMethod(env, track, cAudioTrack, mPlay);
  92
  93     jarray buffer = (*env)->NewByteArray(env, bufferSizeInBytes);
  94
  95     while (data->running)
  96     {
  97         void* pBuffer = (*env)->GetPrimitiveArrayCritical(env, buffer, NULL);
  98
  99         if (pBuffer)
 100         {
 101             aluMixData(device, pBuffer, bufferSizeInSamples);
 102             (*env)->ReleasePrimitiveArrayCritical(env, buffer, pBuffer, 0);
 103
 104             (*env)->CallNonvirtualIntMethod(env, track, cAudioTrack, mWrite, buffer, 0, bufferSizeInBytes);
 105         }
 106         else
 107         {
 108             AL_PRINT("Failed to get pointer to array bytes");
 109         }
 110     }
 111
 112     (*env)->CallNonvirtualVoidMethod(env, track, cAudioTrack, mStop);
 113     (*env)->CallNonvirtualVoidMethod(env, track, cAudioTrack, mRelease);
 114
 115     (*env)->PopLocalFrame(env, NULL);
 116
 117     (*javaVM)->DetachCurrentThread(javaVM);
 118     return NULL;
 119 }
 120
 121 static ALCboolean android_open_playback(ALCdevice *device, const ALCchar *deviceName)
 122 {
 123     JNIEnv* env = GetEnv();
 124     AndroidData* data;
 125     int channels;
 126     int bytes;
 127
 128     if (!cAudioTrack)
 129     {
 130         /* Cache AudioTrack class and it's method id's
 131          * And do this only once!
 132          */
 133
 134         cAudioTrack = (*env)->FindClass(env, "android/media/AudioTrack");
 135         if (!cAudioTrack)
 136         {
 137             AL_PRINT("android.media.AudioTrack class is not found. Are you running at least 1.5 version?");
 138             return ALC_FALSE;
 139         }
 140
 141         cAudioTrack = (*env)->NewGlobalRef(env, cAudioTrack);
 142
 143         mAudioTrack = (*env)->GetMethodID(env, cAudioTrack, "<init>", "(IIIIII)V");
 144         mGetMinBufferSize = (*env)->GetStaticMethodID(env, cAudioTrack, "getMinBufferSize", "(III)I");
 145         mPlay = (*env)->GetMethodID(env, cAudioTrack, "play", "()V");
 146         mStop = (*env)->GetMethodID(env, cAudioTrack, "stop", "()V");
 147         mRelease = (*env)->GetMethodID(env, cAudioTrack, "release", "()V");
 148         mWrite = (*env)->GetMethodID(env, cAudioTrack, "write", "([BII)I");
 149     }
 150
 151     if (!deviceName)
 152     {
 153         deviceName = android_device;
 154     }
 155     else if (strcmp(deviceName, android_device) != 0)
 156     {
 157         return ALC_FALSE;
 158     }
 159
 160     data = (AndroidData*)calloc(1, sizeof(*data));
 161     device->szDeviceName = strdup(deviceName);
 162     device->ExtraData = data;
 163     return ALC_TRUE;
 164 }
 165
 166 static void android_close_playback(ALCdevice *device)
 167 {
 168     AndroidData* data = (AndroidData*)device->ExtraData;
 169     if (data != NULL)
 170     {
 171         free(data);
 172         device->ExtraData = NULL;
 173     }
 174 }
 175
 176 static ALCboolean android_reset_playback(ALCdevice *device)
 177 {
 178     AndroidData* data = (AndroidData*)device->ExtraData;
 179
 180     if (aluChannelsFromFormat(device->Format) >= 2)
 181     {
 182         device->Format = aluBytesFromFormat(device->Format) >= 2 ? AL_FORMAT_STEREO16 : AL_FORMAT_STEREO8;
 183     }
 184     else
 185     {
 186         device->Format = aluBytesFromFormat(device->Format) >= 2 ? AL_FORMAT_MONO16 : AL_FORMAT_MONO8;
 187     }
 188
 189     SetDefaultChannelOrder(device);
 190
 191     data->running = 1;
 192     pthread_create(&data->thread, NULL, thread_function, device);
 193
 194     return ALC_TRUE;
 195 }
 196
 197 static void android_stop_playback(ALCdevice *device)
 198 {
 199     AndroidData* data = (AndroidData*)device->ExtraData;
 200
 201     if (data->running)
 202     {
 203         data->running = 0;
 204         pthread_join(data->thread, NULL);
 205     }
 206 }
 207
 208 static ALCboolean android_open_capture(ALCdevice *pDevice, const ALCchar *deviceName)
 209 {
 210     (void)pDevice;
 211     (void)deviceName;
 212     return ALC_FALSE;
 213 }
 214
 215 static void android_close_capture(ALCdevice *pDevice)
 216 {
 217     (void)pDevice;
 218 }
 219
 220 static void android_start_capture(ALCdevice *pDevice)
 221 {
 222     (void)pDevice;
 223 }
 224
 225 static void android_stop_capture(ALCdevice *pDevice)
 226 {
 227     (void)pDevice;
 228 }
 229
 230 static void android_capture_samples(ALCdevice *pDevice, ALCvoid *pBuffer, ALCuint lSamples)
 231 {
 232     (void)pDevice;
 233     (void)pBuffer;
 234     (void)lSamples;
 235 }
 236
 237 static ALCuint android_available_samples(ALCdevice *pDevice)
 238 {
 239     (void)pDevice;
 240     return 0;
 241 }
 242
 243 static const BackendFuncs android_funcs = {
 244     android_open_playback,
 245     android_close_playback,
 246     android_reset_playback,
 247     android_stop_playback,
 248     android_open_capture,
 249     android_close_capture,
 250     android_start_capture,
 251     android_stop_capture,
 252     android_capture_samples,
 253     android_available_samples
 254 };
 255
 256 void alc_android_init(BackendFuncs *func_list)
 257 {
 258     *func_list = android_funcs;
 259 }
 260
 261 void alc_android_deinit(void)
 262 {
 263     JNIEnv* env = GetEnv();
 264
 265     /* release cached AudioTrack class */
 266     (*env)->DeleteGlobalRef(env, cAudioTrack);
 267 }
 268
 269 void alc_android_probe(int type)
 270 {
 271     if (type == DEVICE_PROBE)
 272     {
 273         AppendDeviceList(android_device);
 274     }
 275     else if (type == ALL_DEVICE_PROBE)
 276     {
 277         AppendAllDeviceList(android_device);
 278     }
 279 }