android_media_AudioRecord.cpp revision 283a9d9e15e095493a7d9800667e49169143e7e3 
1/*
2 * Copyright (C) 2008 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 *      http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17//#define LOG_NDEBUG 0
18
19#define LOG_TAG "AudioRecord-JNI"
20
21#include <inttypes.h>
22#include <jni.h>
23#include <JNIHelp.h>
24#include <android_runtime/AndroidRuntime.h>
25
26#include <utils/Log.h>
27#include <media/AudioRecord.h>
28
29#include "android_media_AudioFormat.h"
30#include "android_media_AudioErrors.h"
31
32// ----------------------------------------------------------------------------
33
34using namespace android;
35
36// ----------------------------------------------------------------------------
37static const char* const kClassPathName = "android/media/AudioRecord";
38static const char* const kAudioAttributesClassPathName = "android/media/AudioAttributes";
39
40struct audio_record_fields_t {
41    // these fields provide access from C++ to the...
42    jmethodID postNativeEventInJava; //... event post callback method
43    jfieldID  nativeRecorderInJavaObj; // provides access to the C++ AudioRecord object
44    jfieldID  nativeCallbackCookie;    // provides access to the AudioRecord callback data
45};
46struct audio_attributes_fields_t {
47    jfieldID  fieldRecSource;    // AudioAttributes.mSource
48    jfieldID  fieldFlags;        // AudioAttributes.mFlags
49    jfieldID  fieldFormattedTags;// AudioAttributes.mFormattedTags
50};
51static audio_attributes_fields_t javaAudioAttrFields;
52static audio_record_fields_t     javaAudioRecordFields;
53
54struct audiorecord_callback_cookie {
55    jclass      audioRecord_class;
56    jobject     audioRecord_ref;
57    bool        busy;
58    Condition   cond;
59};
60
61static Mutex sLock;
62static SortedVector <audiorecord_callback_cookie *> sAudioRecordCallBackCookies;
63
64// ----------------------------------------------------------------------------
65
66#define AUDIORECORD_ERROR_SETUP_ZEROFRAMECOUNT      -16
67#define AUDIORECORD_ERROR_SETUP_INVALIDCHANNELMASK -17
68#define AUDIORECORD_ERROR_SETUP_INVALIDFORMAT       -18
69#define AUDIORECORD_ERROR_SETUP_INVALIDSOURCE       -19
70#define AUDIORECORD_ERROR_SETUP_NATIVEINITFAILED    -20
71
72// ----------------------------------------------------------------------------
73static void recorderCallback(int event, void* user, void *info) {
74
75    audiorecord_callback_cookie *callbackInfo = (audiorecord_callback_cookie *)user;
76    {
77        Mutex::Autolock l(sLock);
78        if (sAudioRecordCallBackCookies.indexOf(callbackInfo) < 0) {
79            return;
80        }
81        callbackInfo->busy = true;
82    }
83
84    switch (event) {
85    case AudioRecord::EVENT_MARKER: {
86        JNIEnv *env = AndroidRuntime::getJNIEnv();
87        if (user != NULL && env != NULL) {
88            env->CallStaticVoidMethod(
89                callbackInfo->audioRecord_class,
90                javaAudioRecordFields.postNativeEventInJava,
91                callbackInfo->audioRecord_ref, event, 0,0, NULL);
92            if (env->ExceptionCheck()) {
93                env->ExceptionDescribe();
94                env->ExceptionClear();
95            }
96        }
97        } break;
98
99    case AudioRecord::EVENT_NEW_POS: {
100        JNIEnv *env = AndroidRuntime::getJNIEnv();
101        if (user != NULL && env != NULL) {
102            env->CallStaticVoidMethod(
103                callbackInfo->audioRecord_class,
104                javaAudioRecordFields.postNativeEventInJava,
105                callbackInfo->audioRecord_ref, event, 0,0, NULL);
106            if (env->ExceptionCheck()) {
107                env->ExceptionDescribe();
108                env->ExceptionClear();
109            }
110        }
111        } break;
112    }
113
114    {
115        Mutex::Autolock l(sLock);
116        callbackInfo->busy = false;
117        callbackInfo->cond.broadcast();
118    }
119}
120
121// ----------------------------------------------------------------------------
122static sp<AudioRecord> getAudioRecord(JNIEnv* env, jobject thiz)
123{
124    Mutex::Autolock l(sLock);
125    AudioRecord* const ar =
126            (AudioRecord*)env->GetLongField(thiz, javaAudioRecordFields.nativeRecorderInJavaObj);
127    return sp<AudioRecord>(ar);
128}
129
130static sp<AudioRecord> setAudioRecord(JNIEnv* env, jobject thiz, const sp<AudioRecord>& ar)
131{
132    Mutex::Autolock l(sLock);
133    sp<AudioRecord> old =
134            (AudioRecord*)env->GetLongField(thiz, javaAudioRecordFields.nativeRecorderInJavaObj);
135    if (ar.get()) {
136        ar->incStrong((void*)setAudioRecord);
137    }
138    if (old != 0) {
139        old->decStrong((void*)setAudioRecord);
140    }
141    env->SetLongField(thiz, javaAudioRecordFields.nativeRecorderInJavaObj, (jlong)ar.get());
142    return old;
143}
144
145// ----------------------------------------------------------------------------
146static jint
147android_media_AudioRecord_setup(JNIEnv *env, jobject thiz, jobject weak_this,
148        jobject jaa, jint sampleRateInHertz, jint channelMask,
149                // Java channel masks map directly to the native definition
150        jint audioFormat, jint buffSizeInBytes, jintArray jSession)
151{
152    //ALOGV(">> Entering android_media_AudioRecord_setup");
153    //ALOGV("sampleRate=%d, audioFormat=%d, channel mask=%x, buffSizeInBytes=%d",
154    //     sampleRateInHertz, audioFormat, channelMask, buffSizeInBytes);
155
156    if (jaa == 0) {
157        ALOGE("Error creating AudioRecord: invalid audio attributes");
158        return (jint) AUDIO_JAVA_ERROR;
159    }
160
161    if (!audio_is_input_channel(channelMask)) {
162        ALOGE("Error creating AudioRecord: channel mask %#x is not valid.", channelMask);
163        return (jint) AUDIORECORD_ERROR_SETUP_INVALIDCHANNELMASK;
164    }
165    uint32_t channelCount = audio_channel_count_from_in_mask(channelMask);
166
167    // compare the format against the Java constants
168    audio_format_t format = audioFormatToNative(audioFormat);
169    if (format == AUDIO_FORMAT_INVALID) {
170        ALOGE("Error creating AudioRecord: unsupported audio format %d.", audioFormat);
171        return (jint) AUDIORECORD_ERROR_SETUP_INVALIDFORMAT;
172    }
173
174    size_t bytesPerSample = audio_bytes_per_sample(format);
175
176    if (buffSizeInBytes == 0) {
177         ALOGE("Error creating AudioRecord: frameCount is 0.");
178        return (jint) AUDIORECORD_ERROR_SETUP_ZEROFRAMECOUNT;
179    }
180    size_t frameSize = channelCount * bytesPerSample;
181    size_t frameCount = buffSizeInBytes / frameSize;
182
183    jclass clazz = env->GetObjectClass(thiz);
184    if (clazz == NULL) {
185        ALOGE("Can't find %s when setting up callback.", kClassPathName);
186        return (jint) AUDIORECORD_ERROR_SETUP_NATIVEINITFAILED;
187    }
188
189    if (jSession == NULL) {
190        ALOGE("Error creating AudioRecord: invalid session ID pointer");
191        return (jint) AUDIO_JAVA_ERROR;
192    }
193
194    jint* nSession = (jint *) env->GetPrimitiveArrayCritical(jSession, NULL);
195    if (nSession == NULL) {
196        ALOGE("Error creating AudioRecord: Error retrieving session id pointer");
197        return (jint) AUDIO_JAVA_ERROR;
198    }
199    int sessionId = nSession[0];
200    env->ReleasePrimitiveArrayCritical(jSession, nSession, 0);
201    nSession = NULL;
202
203    // create an uninitialized AudioRecord object
204    sp<AudioRecord> lpRecorder = new AudioRecord();
205
206    audio_attributes_t *paa = NULL;
207    // read the AudioAttributes values
208    paa = (audio_attributes_t *) calloc(1, sizeof(audio_attributes_t));
209    const jstring jtags =
210            (jstring) env->GetObjectField(jaa, javaAudioAttrFields.fieldFormattedTags);
211    const char* tags = env->GetStringUTFChars(jtags, NULL);
212    // copying array size -1, char array for tags was calloc'd, no need to NULL-terminate it
213    strncpy(paa->tags, tags, AUDIO_ATTRIBUTES_TAGS_MAX_SIZE - 1);
214    env->ReleaseStringUTFChars(jtags, tags);
215    paa->source = (audio_source_t) env->GetIntField(jaa, javaAudioAttrFields.fieldRecSource);
216    paa->flags = (audio_flags_mask_t)env->GetIntField(jaa, javaAudioAttrFields.fieldFlags);
217    ALOGV("AudioRecord_setup for source=%d tags=%s flags=%08x", paa->source, paa->tags, paa->flags);
218
219    audio_input_flags_t flags = AUDIO_INPUT_FLAG_NONE;
220    if (paa->flags & AUDIO_FLAG_HW_HOTWORD) {
221        flags = AUDIO_INPUT_FLAG_HW_HOTWORD;
222    }
223    // create the callback information:
224    // this data will be passed with every AudioRecord callback
225    audiorecord_callback_cookie *lpCallbackData = new audiorecord_callback_cookie;
226    lpCallbackData->audioRecord_class = (jclass)env->NewGlobalRef(clazz);
227    // we use a weak reference so the AudioRecord object can be garbage collected.
228    lpCallbackData->audioRecord_ref = env->NewGlobalRef(weak_this);
229    lpCallbackData->busy = false;
230
231    const status_t status = lpRecorder->set(paa->source,
232        sampleRateInHertz,
233        format,        // word length, PCM
234        channelMask,
235        frameCount,
236        recorderCallback,// callback_t
237        lpCallbackData,// void* user
238        0,             // notificationFrames,
239        true,          // threadCanCallJava
240        sessionId,
241        AudioRecord::TRANSFER_DEFAULT,
242        flags);
243
244    if (status != NO_ERROR) {
245        ALOGE("Error creating AudioRecord instance: initialization check failed with status %d.",
246                status);
247        goto native_init_failure;
248    }
249
250    nSession = (jint *) env->GetPrimitiveArrayCritical(jSession, NULL);
251    if (nSession == NULL) {
252        ALOGE("Error creating AudioRecord: Error retrieving session id pointer");
253        goto native_init_failure;
254    }
255    // read the audio session ID back from AudioRecord in case a new session was created during set()
256    nSession[0] = lpRecorder->getSessionId();
257    env->ReleasePrimitiveArrayCritical(jSession, nSession, 0);
258    nSession = NULL;
259
260    {   // scope for the lock
261        Mutex::Autolock l(sLock);
262        sAudioRecordCallBackCookies.add(lpCallbackData);
263    }
264    // save our newly created C++ AudioRecord in the "nativeRecorderInJavaObj" field
265    // of the Java object
266    setAudioRecord(env, thiz, lpRecorder);
267
268    // save our newly created callback information in the "nativeCallbackCookie" field
269    // of the Java object (in mNativeCallbackCookie) so we can free the memory in finalize()
270    env->SetLongField(thiz, javaAudioRecordFields.nativeCallbackCookie, (jlong)lpCallbackData);
271
272    return (jint) AUDIO_JAVA_SUCCESS;
273
274    // failure:
275native_init_failure:
276    env->DeleteGlobalRef(lpCallbackData->audioRecord_class);
277    env->DeleteGlobalRef(lpCallbackData->audioRecord_ref);
278    delete lpCallbackData;
279    env->SetLongField(thiz, javaAudioRecordFields.nativeCallbackCookie, 0);
280
281    return (jint) AUDIORECORD_ERROR_SETUP_NATIVEINITFAILED;
282}
283
284
285
286// ----------------------------------------------------------------------------
287static jint
288android_media_AudioRecord_start(JNIEnv *env, jobject thiz, jint event, jint triggerSession)
289{
290    sp<AudioRecord> lpRecorder = getAudioRecord(env, thiz);
291    if (lpRecorder == NULL ) {
292        jniThrowException(env, "java/lang/IllegalStateException", NULL);
293        return (jint) AUDIO_JAVA_ERROR;
294    }
295
296    return nativeToJavaStatus(
297            lpRecorder->start((AudioSystem::sync_event_t)event, triggerSession));
298}
299
300
301// ----------------------------------------------------------------------------
302static void
303android_media_AudioRecord_stop(JNIEnv *env, jobject thiz)
304{
305    sp<AudioRecord> lpRecorder = getAudioRecord(env, thiz);
306    if (lpRecorder == NULL ) {
307        jniThrowException(env, "java/lang/IllegalStateException", NULL);
308        return;
309    }
310
311    lpRecorder->stop();
312    //ALOGV("Called lpRecorder->stop()");
313}
314
315
316// ----------------------------------------------------------------------------
317
318#define CALLBACK_COND_WAIT_TIMEOUT_MS 1000
319static void android_media_AudioRecord_release(JNIEnv *env,  jobject thiz) {
320    sp<AudioRecord> lpRecorder = setAudioRecord(env, thiz, 0);
321    if (lpRecorder == NULL) {
322        return;
323    }
324    ALOGV("About to delete lpRecorder: %p", lpRecorder.get());
325    lpRecorder->stop();
326
327    audiorecord_callback_cookie *lpCookie = (audiorecord_callback_cookie *)env->GetLongField(
328        thiz, javaAudioRecordFields.nativeCallbackCookie);
329
330    // reset the native resources in the Java object so any attempt to access
331    // them after a call to release fails.
332    env->SetLongField(thiz, javaAudioRecordFields.nativeCallbackCookie, 0);
333
334    // delete the callback information
335    if (lpCookie) {
336        Mutex::Autolock l(sLock);
337        ALOGV("deleting lpCookie: %p", lpCookie);
338        while (lpCookie->busy) {
339            if (lpCookie->cond.waitRelative(sLock,
340                                            milliseconds(CALLBACK_COND_WAIT_TIMEOUT_MS)) !=
341                                                    NO_ERROR) {
342                break;
343            }
344        }
345        sAudioRecordCallBackCookies.remove(lpCookie);
346        env->DeleteGlobalRef(lpCookie->audioRecord_class);
347        env->DeleteGlobalRef(lpCookie->audioRecord_ref);
348        delete lpCookie;
349    }
350}
351
352
353// ----------------------------------------------------------------------------
354static void android_media_AudioRecord_finalize(JNIEnv *env,  jobject thiz) {
355    android_media_AudioRecord_release(env, thiz);
356}
357
358
359// ----------------------------------------------------------------------------
360static jint android_media_AudioRecord_readInByteArray(JNIEnv *env,  jobject thiz,
361                                                        jbyteArray javaAudioData,
362                                                        jint offsetInBytes, jint sizeInBytes) {
363    jbyte* recordBuff = NULL;
364    // get the audio recorder from which we'll read new audio samples
365    sp<AudioRecord> lpRecorder = getAudioRecord(env, thiz);
366    if (lpRecorder == NULL) {
367        ALOGE("Unable to retrieve AudioRecord object, can't record");
368        return 0;
369    }
370
371    if (!javaAudioData) {
372        ALOGE("Invalid Java array to store recorded audio, can't record");
373        return 0;
374    }
375
376    // get the pointer to where we'll record the audio
377    // NOTE: We may use GetPrimitiveArrayCritical() when the JNI implementation changes in such
378    // a way that it becomes much more efficient. When doing so, we will have to prevent the
379    // AudioSystem callback to be called while in critical section (in case of media server
380    // process crash for instance)
381    recordBuff = (jbyte *)env->GetByteArrayElements(javaAudioData, NULL);
382
383    if (recordBuff == NULL) {
384        ALOGE("Error retrieving destination for recorded audio data, can't record");
385        return 0;
386    }
387
388    // read the new audio data from the native AudioRecord object
389    ssize_t recorderBuffSize = lpRecorder->frameCount()*lpRecorder->frameSize();
390    ssize_t readSize = lpRecorder->read(recordBuff + offsetInBytes,
391                                        sizeInBytes > (jint)recorderBuffSize ?
392                                            (jint)recorderBuffSize : sizeInBytes );
393    env->ReleaseByteArrayElements(javaAudioData, recordBuff, 0);
394
395    if (readSize < 0) {
396        readSize = (jint)AUDIO_JAVA_INVALID_OPERATION;
397    }
398    return (jint) readSize;
399}
400
401// ----------------------------------------------------------------------------
402static jint android_media_AudioRecord_readInShortArray(JNIEnv *env,  jobject thiz,
403                                                        jshortArray javaAudioData,
404                                                        jint offsetInShorts, jint sizeInShorts) {
405
406    jshort* recordBuff = NULL;
407    // get the audio recorder from which we'll read new audio samples
408    sp<AudioRecord> lpRecorder = getAudioRecord(env, thiz);
409    if (lpRecorder == NULL) {
410        ALOGE("Unable to retrieve AudioRecord object, can't record");
411        return 0;
412    }
413
414    if (!javaAudioData) {
415        ALOGE("Invalid Java array to store recorded audio, can't record");
416        return 0;
417    }
418
419    // get the pointer to where we'll record the audio
420    // NOTE: We may use GetPrimitiveArrayCritical() when the JNI implementation changes in such
421    // a way that it becomes much more efficient. When doing so, we will have to prevent the
422    // AudioSystem callback to be called while in critical section (in case of media server
423    // process crash for instance)
424    recordBuff = (jshort *)env->GetShortArrayElements(javaAudioData, NULL);
425
426    if (recordBuff == NULL) {
427        ALOGE("Error retrieving destination for recorded audio data, can't record");
428        return 0;
429    }
430
431    // read the new audio data from the native AudioRecord object
432    const size_t recorderBuffSize = lpRecorder->frameCount()*lpRecorder->frameSize();
433    const size_t sizeInBytes = sizeInShorts * sizeof(short);
434    ssize_t readSize = lpRecorder->read(recordBuff + offsetInShorts,
435                                        sizeInBytes > recorderBuffSize ?
436                                            recorderBuffSize : sizeInBytes);
437
438    env->ReleaseShortArrayElements(javaAudioData, recordBuff, 0);
439
440    if (readSize < 0) {
441        readSize = (jint)AUDIO_JAVA_INVALID_OPERATION;
442    } else {
443        readSize /= sizeof(short);
444    }
445    return (jint) readSize;
446}
447
448// ----------------------------------------------------------------------------
449static jint android_media_AudioRecord_readInDirectBuffer(JNIEnv *env,  jobject thiz,
450                                                  jobject jBuffer, jint sizeInBytes) {
451    // get the audio recorder from which we'll read new audio samples
452    sp<AudioRecord> lpRecorder = getAudioRecord(env, thiz);
453    if (lpRecorder==NULL)
454        return 0;
455
456    // direct buffer and direct access supported?
457    long capacity = env->GetDirectBufferCapacity(jBuffer);
458    if (capacity == -1) {
459        // buffer direct access is not supported
460        ALOGE("Buffer direct access is not supported, can't record");
461        return 0;
462    }
463    //ALOGV("capacity = %ld", capacity);
464    jbyte* nativeFromJavaBuf = (jbyte*) env->GetDirectBufferAddress(jBuffer);
465    if (nativeFromJavaBuf==NULL) {
466        ALOGE("Buffer direct access is not supported, can't record");
467        return 0;
468    }
469
470    // read new data from the recorder
471    ssize_t readSize = lpRecorder->read(nativeFromJavaBuf,
472                                   capacity < sizeInBytes ? capacity : sizeInBytes);
473    if (readSize < 0) {
474        readSize = (jint)AUDIO_JAVA_INVALID_OPERATION;
475    }
476    return (jint)readSize;
477}
478
479
480// ----------------------------------------------------------------------------
481static jint android_media_AudioRecord_set_marker_pos(JNIEnv *env,  jobject thiz,
482        jint markerPos) {
483
484    sp<AudioRecord> lpRecorder = getAudioRecord(env, thiz);
485    if (lpRecorder == NULL) {
486        jniThrowException(env, "java/lang/IllegalStateException",
487            "Unable to retrieve AudioRecord pointer for setMarkerPosition()");
488        return (jint)AUDIO_JAVA_ERROR;
489    }
490    return nativeToJavaStatus( lpRecorder->setMarkerPosition(markerPos) );
491}
492
493
494// ----------------------------------------------------------------------------
495static jint android_media_AudioRecord_get_marker_pos(JNIEnv *env,  jobject thiz) {
496
497    sp<AudioRecord> lpRecorder = getAudioRecord(env, thiz);
498    uint32_t markerPos = 0;
499
500    if (lpRecorder == NULL) {
501        jniThrowException(env, "java/lang/IllegalStateException",
502            "Unable to retrieve AudioRecord pointer for getMarkerPosition()");
503        return (jint)AUDIO_JAVA_ERROR;
504    }
505    lpRecorder->getMarkerPosition(&markerPos);
506    return (jint)markerPos;
507}
508
509
510// ----------------------------------------------------------------------------
511static jint android_media_AudioRecord_set_pos_update_period(JNIEnv *env,  jobject thiz,
512        jint period) {
513
514    sp<AudioRecord> lpRecorder = getAudioRecord(env, thiz);
515
516    if (lpRecorder == NULL) {
517        jniThrowException(env, "java/lang/IllegalStateException",
518            "Unable to retrieve AudioRecord pointer for setPositionUpdatePeriod()");
519        return (jint)AUDIO_JAVA_ERROR;
520    }
521    return nativeToJavaStatus( lpRecorder->setPositionUpdatePeriod(period) );
522}
523
524
525// ----------------------------------------------------------------------------
526static jint android_media_AudioRecord_get_pos_update_period(JNIEnv *env,  jobject thiz) {
527
528    sp<AudioRecord> lpRecorder = getAudioRecord(env, thiz);
529    uint32_t period = 0;
530
531    if (lpRecorder == NULL) {
532        jniThrowException(env, "java/lang/IllegalStateException",
533            "Unable to retrieve AudioRecord pointer for getPositionUpdatePeriod()");
534        return (jint)AUDIO_JAVA_ERROR;
535    }
536    lpRecorder->getPositionUpdatePeriod(&period);
537    return (jint)period;
538}
539
540
541// ----------------------------------------------------------------------------
542// returns the minimum required size for the successful creation of an AudioRecord instance.
543// returns 0 if the parameter combination is not supported.
544// return -1 if there was an error querying the buffer size.
545static jint android_media_AudioRecord_get_min_buff_size(JNIEnv *env,  jobject thiz,
546    jint sampleRateInHertz, jint channelCount, jint audioFormat) {
547
548    ALOGV(">> android_media_AudioRecord_get_min_buff_size(%d, %d, %d)",
549          sampleRateInHertz, channelCount, audioFormat);
550
551    size_t frameCount = 0;
552    audio_format_t format = audioFormatToNative(audioFormat);
553    status_t result = AudioRecord::getMinFrameCount(&frameCount,
554            sampleRateInHertz,
555            format,
556            audio_channel_in_mask_from_count(channelCount));
557
558    if (result == BAD_VALUE) {
559        return 0;
560    }
561    if (result != NO_ERROR) {
562        return -1;
563    }
564    return frameCount * channelCount * audio_bytes_per_sample(format);
565}
566
567
568// ----------------------------------------------------------------------------
569// ----------------------------------------------------------------------------
570static JNINativeMethod gMethods[] = {
571    // name,               signature,  funcPtr
572    {"native_start",         "(II)I",    (void *)android_media_AudioRecord_start},
573    {"native_stop",          "()V",    (void *)android_media_AudioRecord_stop},
574    {"native_setup",         "(Ljava/lang/Object;Ljava/lang/Object;IIII[I)I",
575                                       (void *)android_media_AudioRecord_setup},
576    {"native_finalize",      "()V",    (void *)android_media_AudioRecord_finalize},
577    {"native_release",       "()V",    (void *)android_media_AudioRecord_release},
578    {"native_read_in_byte_array",
579                             "([BII)I", (void *)android_media_AudioRecord_readInByteArray},
580    {"native_read_in_short_array",
581                             "([SII)I", (void *)android_media_AudioRecord_readInShortArray},
582    {"native_read_in_direct_buffer","(Ljava/lang/Object;I)I",
583                                       (void *)android_media_AudioRecord_readInDirectBuffer},
584    {"native_set_marker_pos","(I)I",   (void *)android_media_AudioRecord_set_marker_pos},
585    {"native_get_marker_pos","()I",    (void *)android_media_AudioRecord_get_marker_pos},
586    {"native_set_pos_update_period",
587                             "(I)I",   (void *)android_media_AudioRecord_set_pos_update_period},
588    {"native_get_pos_update_period",
589                             "()I",    (void *)android_media_AudioRecord_get_pos_update_period},
590    {"native_get_min_buff_size",
591                             "(III)I",   (void *)android_media_AudioRecord_get_min_buff_size},
592};
593
594// field names found in android/media/AudioRecord.java
595#define JAVA_POSTEVENT_CALLBACK_NAME  "postEventFromNative"
596#define JAVA_NATIVERECORDERINJAVAOBJ_FIELD_NAME  "mNativeRecorderInJavaObj"
597#define JAVA_NATIVECALLBACKINFO_FIELD_NAME       "mNativeCallbackCookie"
598
599// ----------------------------------------------------------------------------
600int register_android_media_AudioRecord(JNIEnv *env)
601{
602    javaAudioRecordFields.postNativeEventInJava = NULL;
603    javaAudioRecordFields.nativeRecorderInJavaObj = NULL;
604    javaAudioRecordFields.nativeCallbackCookie = NULL;
605
606
607    // Get the AudioRecord class
608    jclass audioRecordClass = env->FindClass(kClassPathName);
609    if (audioRecordClass == NULL) {
610        ALOGE("Can't find %s", kClassPathName);
611        return -1;
612    }
613    // Get the postEvent method
614    javaAudioRecordFields.postNativeEventInJava = env->GetStaticMethodID(
615            audioRecordClass,
616            JAVA_POSTEVENT_CALLBACK_NAME, "(Ljava/lang/Object;IIILjava/lang/Object;)V");
617    if (javaAudioRecordFields.postNativeEventInJava == NULL) {
618        ALOGE("Can't find AudioRecord.%s", JAVA_POSTEVENT_CALLBACK_NAME);
619        return -1;
620    }
621
622    // Get the variables
623    //    mNativeRecorderInJavaObj
624    javaAudioRecordFields.nativeRecorderInJavaObj =
625        env->GetFieldID(audioRecordClass,
626                        JAVA_NATIVERECORDERINJAVAOBJ_FIELD_NAME, "J");
627    if (javaAudioRecordFields.nativeRecorderInJavaObj == NULL) {
628        ALOGE("Can't find AudioRecord.%s", JAVA_NATIVERECORDERINJAVAOBJ_FIELD_NAME);
629        return -1;
630    }
631    //     mNativeCallbackCookie
632    javaAudioRecordFields.nativeCallbackCookie = env->GetFieldID(
633            audioRecordClass,
634            JAVA_NATIVECALLBACKINFO_FIELD_NAME, "J");
635    if (javaAudioRecordFields.nativeCallbackCookie == NULL) {
636        ALOGE("Can't find AudioRecord.%s", JAVA_NATIVECALLBACKINFO_FIELD_NAME);
637        return -1;
638    }
639
640    // Get the AudioAttributes class and fields
641    jclass audioAttrClass = env->FindClass(kAudioAttributesClassPathName);
642    if (audioAttrClass == NULL) {
643        ALOGE("Can't find %s", kAudioAttributesClassPathName);
644        return -1;
645    }
646    jclass audioAttributesClassRef = (jclass)env->NewGlobalRef(audioAttrClass);
647    javaAudioAttrFields.fieldRecSource = env->GetFieldID(audioAttributesClassRef, "mSource", "I");
648    javaAudioAttrFields.fieldFlags = env->GetFieldID(audioAttributesClassRef, "mFlags", "I");
649    javaAudioAttrFields.fieldFormattedTags =
650            env->GetFieldID(audioAttributesClassRef, "mFormattedTags", "Ljava/lang/String;");
651    env->DeleteGlobalRef(audioAttributesClassRef);
652    if (javaAudioAttrFields.fieldRecSource == NULL
653            || javaAudioAttrFields.fieldFlags == NULL
654            || javaAudioAttrFields.fieldFormattedTags == NULL) {
655        ALOGE("Can't initialize AudioAttributes fields");
656        return -1;
657    }
658
659    return AndroidRuntime::registerNativeMethods(env,
660            kClassPathName, gMethods, NELEM(gMethods));
661}
662
663// ----------------------------------------------------------------------------
664