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      1 /*
      2  * Copyright (C) 2010 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 "MtpDeviceJNI"
     20 #include "utils/Log.h"
     21 
     22 #include <stdio.h>
     23 #include <assert.h>
     24 #include <limits.h>
     25 #include <unistd.h>
     26 #include <fcntl.h>
     27 
     28 #include "jni.h"
     29 #include "JNIHelp.h"
     30 #include "android_runtime/AndroidRuntime.h"
     31 #include "android_runtime/Log.h"
     32 #include "private/android_filesystem_config.h"
     33 
     34 #include "MtpTypes.h"
     35 #include "MtpDevice.h"
     36 #include "MtpDeviceInfo.h"
     37 #include "MtpStorageInfo.h"
     38 #include "MtpObjectInfo.h"
     39 
     40 using namespace android;
     41 
     42 // ----------------------------------------------------------------------------
     43 
     44 static jfieldID field_context;
     45 
     46 jclass clazz_deviceInfo;
     47 jclass clazz_storageInfo;
     48 jclass clazz_objectInfo;
     49 
     50 jmethodID constructor_deviceInfo;
     51 jmethodID constructor_storageInfo;
     52 jmethodID constructor_objectInfo;
     53 
     54 // MtpDeviceInfo fields
     55 static jfieldID field_deviceInfo_manufacturer;
     56 static jfieldID field_deviceInfo_model;
     57 static jfieldID field_deviceInfo_version;
     58 static jfieldID field_deviceInfo_serialNumber;
     59 
     60 // MtpStorageInfo fields
     61 static jfieldID field_storageInfo_storageId;
     62 static jfieldID field_storageInfo_maxCapacity;
     63 static jfieldID field_storageInfo_freeSpace;
     64 static jfieldID field_storageInfo_description;
     65 static jfieldID field_storageInfo_volumeIdentifier;
     66 
     67 // MtpObjectInfo fields
     68 static jfieldID field_objectInfo_handle;
     69 static jfieldID field_objectInfo_storageId;
     70 static jfieldID field_objectInfo_format;
     71 static jfieldID field_objectInfo_protectionStatus;
     72 static jfieldID field_objectInfo_compressedSize;
     73 static jfieldID field_objectInfo_thumbFormat;
     74 static jfieldID field_objectInfo_thumbCompressedSize;
     75 static jfieldID field_objectInfo_thumbPixWidth;
     76 static jfieldID field_objectInfo_thumbPixHeight;
     77 static jfieldID field_objectInfo_imagePixWidth;
     78 static jfieldID field_objectInfo_imagePixHeight;
     79 static jfieldID field_objectInfo_imagePixDepth;
     80 static jfieldID field_objectInfo_parent;
     81 static jfieldID field_objectInfo_associationType;
     82 static jfieldID field_objectInfo_associationDesc;
     83 static jfieldID field_objectInfo_sequenceNumber;
     84 static jfieldID field_objectInfo_name;
     85 static jfieldID field_objectInfo_dateCreated;
     86 static jfieldID field_objectInfo_dateModified;
     87 static jfieldID field_objectInfo_keywords;
     88 
     89 MtpDevice* get_device_from_object(JNIEnv* env, jobject javaDevice)
     90 {
     91     return (MtpDevice*)env->GetIntField(javaDevice, field_context);
     92 }
     93 
     94 static void checkAndClearExceptionFromCallback(JNIEnv* env, const char* methodName) {
     95     if (env->ExceptionCheck()) {
     96         ALOGE("An exception was thrown by callback '%s'.", methodName);
     97         LOGE_EX(env);
     98         env->ExceptionClear();
     99     }
    100 }
    101 
    102 // ----------------------------------------------------------------------------
    103 
    104 static jboolean
    105 android_mtp_MtpDevice_open(JNIEnv *env, jobject thiz, jstring deviceName, jint fd)
    106 {
    107     const char *deviceNameStr = env->GetStringUTFChars(deviceName, NULL);
    108     if (deviceNameStr == NULL) {
    109         return false;
    110     }
    111 
    112     MtpDevice* device = MtpDevice::open(deviceNameStr, fd);
    113     env->ReleaseStringUTFChars(deviceName, deviceNameStr);
    114 
    115     if (device)
    116         env->SetIntField(thiz, field_context, (int)device);
    117     return (device != NULL);
    118 }
    119 
    120 static void
    121 android_mtp_MtpDevice_close(JNIEnv *env, jobject thiz)
    122 {
    123     MtpDevice* device = get_device_from_object(env, thiz);
    124     if (device) {
    125         device->close();
    126         delete device;
    127         env->SetIntField(thiz, field_context, 0);
    128     }
    129 }
    130 
    131 static jobject
    132 android_mtp_MtpDevice_get_device_info(JNIEnv *env, jobject thiz)
    133 {
    134     MtpDevice* device = get_device_from_object(env, thiz);
    135     if (!device) {
    136         ALOGD("android_mtp_MtpDevice_get_device_info device is null");
    137         return NULL;
    138     }
    139     MtpDeviceInfo* deviceInfo = device->getDeviceInfo();
    140     if (!deviceInfo) {
    141         ALOGD("android_mtp_MtpDevice_get_device_info deviceInfo is null");
    142         return NULL;
    143     }
    144     jobject info = env->NewObject(clazz_deviceInfo, constructor_deviceInfo);
    145     if (info == NULL) {
    146         ALOGE("Could not create a MtpDeviceInfo object");
    147         delete deviceInfo;
    148         return NULL;
    149     }
    150 
    151     if (deviceInfo->mManufacturer)
    152         env->SetObjectField(info, field_deviceInfo_manufacturer,
    153             env->NewStringUTF(deviceInfo->mManufacturer));
    154     if (deviceInfo->mModel)
    155         env->SetObjectField(info, field_deviceInfo_model,
    156             env->NewStringUTF(deviceInfo->mModel));
    157     if (deviceInfo->mVersion)
    158         env->SetObjectField(info, field_deviceInfo_version,
    159             env->NewStringUTF(deviceInfo->mVersion));
    160     if (deviceInfo->mSerial)
    161         env->SetObjectField(info, field_deviceInfo_serialNumber,
    162             env->NewStringUTF(deviceInfo->mSerial));
    163 
    164     delete deviceInfo;
    165     return info;
    166 }
    167 
    168 static jintArray
    169 android_mtp_MtpDevice_get_storage_ids(JNIEnv *env, jobject thiz)
    170 {
    171     MtpDevice* device = get_device_from_object(env, thiz);
    172     if (!device)
    173         return NULL;
    174     MtpStorageIDList* storageIDs = device->getStorageIDs();
    175     if (!storageIDs)
    176         return NULL;
    177 
    178     int length = storageIDs->size();
    179     jintArray array = env->NewIntArray(length);
    180     // FIXME is this cast safe?
    181     env->SetIntArrayRegion(array, 0, length, (const jint *)storageIDs->array());
    182 
    183     delete storageIDs;
    184     return array;
    185 }
    186 
    187 static jobject
    188 android_mtp_MtpDevice_get_storage_info(JNIEnv *env, jobject thiz, jint storageID)
    189 {
    190     MtpDevice* device = get_device_from_object(env, thiz);
    191     if (!device)
    192         return NULL;
    193     MtpStorageInfo* storageInfo = device->getStorageInfo(storageID);
    194     if (!storageInfo)
    195         return NULL;
    196 
    197     jobject info = env->NewObject(clazz_storageInfo, constructor_storageInfo);
    198     if (info == NULL) {
    199         ALOGE("Could not create a MtpStorageInfo object");
    200         delete storageInfo;
    201         return NULL;
    202     }
    203 
    204     if (storageInfo->mStorageID)
    205         env->SetIntField(info, field_storageInfo_storageId, storageInfo->mStorageID);
    206     if (storageInfo->mMaxCapacity)
    207         env->SetLongField(info, field_storageInfo_maxCapacity, storageInfo->mMaxCapacity);
    208     if (storageInfo->mFreeSpaceBytes)
    209         env->SetLongField(info, field_storageInfo_freeSpace, storageInfo->mFreeSpaceBytes);
    210     if (storageInfo->mStorageDescription)
    211         env->SetObjectField(info, field_storageInfo_description,
    212             env->NewStringUTF(storageInfo->mStorageDescription));
    213     if (storageInfo->mVolumeIdentifier)
    214         env->SetObjectField(info, field_storageInfo_volumeIdentifier,
    215             env->NewStringUTF(storageInfo->mVolumeIdentifier));
    216 
    217     delete storageInfo;
    218     return info;
    219 }
    220 
    221 static jintArray
    222 android_mtp_MtpDevice_get_object_handles(JNIEnv *env, jobject thiz,
    223         jint storageID, jint format, jint objectID)
    224 {
    225     MtpDevice* device = get_device_from_object(env, thiz);
    226     if (!device)
    227         return NULL;
    228     MtpObjectHandleList* handles = device->getObjectHandles(storageID, format, objectID);
    229     if (!handles)
    230         return NULL;
    231 
    232     int length = handles->size();
    233     jintArray array = env->NewIntArray(length);
    234     // FIXME is this cast safe?
    235     env->SetIntArrayRegion(array, 0, length, (const jint *)handles->array());
    236 
    237     delete handles;
    238     return array;
    239 }
    240 
    241 static jobject
    242 android_mtp_MtpDevice_get_object_info(JNIEnv *env, jobject thiz, jint objectID)
    243 {
    244     MtpDevice* device = get_device_from_object(env, thiz);
    245     if (!device)
    246         return NULL;
    247     MtpObjectInfo* objectInfo = device->getObjectInfo(objectID);
    248     if (!objectInfo)
    249         return NULL;
    250     jobject info = env->NewObject(clazz_objectInfo, constructor_objectInfo);
    251     if (info == NULL) {
    252         ALOGE("Could not create a MtpObjectInfo object");
    253         delete objectInfo;
    254         return NULL;
    255     }
    256 
    257     if (objectInfo->mHandle)
    258         env->SetIntField(info, field_objectInfo_handle, objectInfo->mHandle);
    259     if (objectInfo->mStorageID)
    260         env->SetIntField(info, field_objectInfo_storageId, objectInfo->mStorageID);
    261     if (objectInfo->mFormat)
    262         env->SetIntField(info, field_objectInfo_format, objectInfo->mFormat);
    263     if (objectInfo->mProtectionStatus)
    264         env->SetIntField(info, field_objectInfo_protectionStatus, objectInfo->mProtectionStatus);
    265     if (objectInfo->mCompressedSize)
    266         env->SetIntField(info, field_objectInfo_compressedSize, objectInfo->mCompressedSize);
    267     if (objectInfo->mThumbFormat)
    268         env->SetIntField(info, field_objectInfo_thumbFormat, objectInfo->mThumbFormat);
    269     if (objectInfo->mThumbCompressedSize)
    270         env->SetIntField(info, field_objectInfo_thumbCompressedSize, objectInfo->mThumbCompressedSize);
    271     if (objectInfo->mThumbPixWidth)
    272         env->SetIntField(info, field_objectInfo_thumbPixWidth, objectInfo->mThumbPixWidth);
    273     if (objectInfo->mThumbPixHeight)
    274         env->SetIntField(info, field_objectInfo_thumbPixHeight, objectInfo->mThumbPixHeight);
    275     if (objectInfo->mImagePixWidth)
    276         env->SetIntField(info, field_objectInfo_imagePixWidth, objectInfo->mImagePixWidth);
    277     if (objectInfo->mImagePixHeight)
    278         env->SetIntField(info, field_objectInfo_imagePixHeight, objectInfo->mImagePixHeight);
    279     if (objectInfo->mImagePixDepth)
    280         env->SetIntField(info, field_objectInfo_imagePixDepth, objectInfo->mImagePixDepth);
    281     if (objectInfo->mParent)
    282         env->SetIntField(info, field_objectInfo_parent, objectInfo->mParent);
    283     if (objectInfo->mAssociationType)
    284         env->SetIntField(info, field_objectInfo_associationType, objectInfo->mAssociationType);
    285     if (objectInfo->mAssociationDesc)
    286         env->SetIntField(info, field_objectInfo_associationDesc, objectInfo->mAssociationDesc);
    287     if (objectInfo->mSequenceNumber)
    288         env->SetIntField(info, field_objectInfo_sequenceNumber, objectInfo->mSequenceNumber);
    289     if (objectInfo->mName)
    290         env->SetObjectField(info, field_objectInfo_name, env->NewStringUTF(objectInfo->mName));
    291     if (objectInfo->mDateCreated)
    292         env->SetLongField(info, field_objectInfo_dateCreated, objectInfo->mDateCreated * 1000LL);
    293     if (objectInfo->mDateModified)
    294         env->SetLongField(info, field_objectInfo_dateModified, objectInfo->mDateModified * 1000LL);
    295     if (objectInfo->mKeywords)
    296         env->SetObjectField(info, field_objectInfo_keywords,
    297             env->NewStringUTF(objectInfo->mKeywords));
    298 
    299     delete objectInfo;
    300     return info;
    301 }
    302 
    303 struct get_object_callback_data {
    304     JNIEnv *env;
    305     jbyteArray array;
    306 };
    307 
    308 static bool get_object_callback(void* data, int offset, int length, void* clientData)
    309 {
    310     get_object_callback_data* cbData = (get_object_callback_data *)clientData;
    311     cbData->env->SetByteArrayRegion(cbData->array, offset, length, (jbyte *)data);
    312     return true;
    313 }
    314 
    315 static jbyteArray
    316 android_mtp_MtpDevice_get_object(JNIEnv *env, jobject thiz, jint objectID, jint objectSize)
    317 {
    318     MtpDevice* device = get_device_from_object(env, thiz);
    319     if (!device)
    320         return NULL;
    321 
    322     jbyteArray array = env->NewByteArray(objectSize);
    323     if (!array) {
    324         jniThrowException(env, "java/lang/OutOfMemoryError", NULL);
    325         return NULL;
    326     }
    327 
    328     get_object_callback_data data;
    329     data.env = env;
    330     data.array = array;
    331 
    332     if (device->readObject(objectID, get_object_callback, objectSize, &data))
    333         return array;
    334     return NULL;
    335 }
    336 
    337 static jbyteArray
    338 android_mtp_MtpDevice_get_thumbnail(JNIEnv *env, jobject thiz, jint objectID)
    339 {
    340     MtpDevice* device = get_device_from_object(env, thiz);
    341     if (!device)
    342         return NULL;
    343 
    344     int length;
    345     void* thumbnail = device->getThumbnail(objectID, length);
    346     if (! thumbnail)
    347         return NULL;
    348     jbyteArray array = env->NewByteArray(length);
    349     env->SetByteArrayRegion(array, 0, length, (const jbyte *)thumbnail);
    350 
    351     free(thumbnail);
    352     return array;
    353 }
    354 
    355 static jboolean
    356 android_mtp_MtpDevice_delete_object(JNIEnv *env, jobject thiz, jint object_id)
    357 {
    358     MtpDevice* device = get_device_from_object(env, thiz);
    359     if (device)
    360         return device->deleteObject(object_id);
    361     else
    362         return NULL;
    363 }
    364 
    365 static jlong
    366 android_mtp_MtpDevice_get_parent(JNIEnv *env, jobject thiz, jint object_id)
    367 {
    368     MtpDevice* device = get_device_from_object(env, thiz);
    369     if (device)
    370         return device->getParent(object_id);
    371     else
    372         return -1;
    373 }
    374 
    375 static jlong
    376 android_mtp_MtpDevice_get_storage_id(JNIEnv *env, jobject thiz, jint object_id)
    377 {
    378     MtpDevice* device = get_device_from_object(env, thiz);
    379     if (device)
    380         return device->getStorageID(object_id);
    381     else
    382         return -1;
    383 }
    384 
    385 static jboolean
    386 android_mtp_MtpDevice_import_file(JNIEnv *env, jobject thiz, jint object_id, jstring dest_path)
    387 {
    388     MtpDevice* device = get_device_from_object(env, thiz);
    389     if (device) {
    390         const char *destPathStr = env->GetStringUTFChars(dest_path, NULL);
    391         if (destPathStr == NULL) {
    392             return false;
    393         }
    394 
    395         bool result = device->readObject(object_id, destPathStr, AID_SDCARD_RW, 0664);
    396         env->ReleaseStringUTFChars(dest_path, destPathStr);
    397         return result;
    398     }
    399 
    400     return false;
    401 }
    402 
    403 // ----------------------------------------------------------------------------
    404 
    405 static JNINativeMethod gMethods[] = {
    406     {"native_open",             "(Ljava/lang/String;I)Z",
    407                                         (void *)android_mtp_MtpDevice_open},
    408     {"native_close",            "()V",  (void *)android_mtp_MtpDevice_close},
    409     {"native_get_device_info",  "()Landroid/mtp/MtpDeviceInfo;",
    410                                         (void *)android_mtp_MtpDevice_get_device_info},
    411     {"native_get_storage_ids",  "()[I", (void *)android_mtp_MtpDevice_get_storage_ids},
    412     {"native_get_storage_info", "(I)Landroid/mtp/MtpStorageInfo;",
    413                                         (void *)android_mtp_MtpDevice_get_storage_info},
    414     {"native_get_object_handles","(III)[I",
    415                                         (void *)android_mtp_MtpDevice_get_object_handles},
    416     {"native_get_object_info",  "(I)Landroid/mtp/MtpObjectInfo;",
    417                                         (void *)android_mtp_MtpDevice_get_object_info},
    418     {"native_get_object",       "(II)[B",(void *)android_mtp_MtpDevice_get_object},
    419     {"native_get_thumbnail",    "(I)[B",(void *)android_mtp_MtpDevice_get_thumbnail},
    420     {"native_delete_object",    "(I)Z", (void *)android_mtp_MtpDevice_delete_object},
    421     {"native_get_parent",       "(I)J", (void *)android_mtp_MtpDevice_get_parent},
    422     {"native_get_storage_id",   "(I)J", (void *)android_mtp_MtpDevice_get_storage_id},
    423     {"native_import_file",     "(ILjava/lang/String;)Z",
    424                                         (void *)android_mtp_MtpDevice_import_file},
    425 };
    426 
    427 static const char* const kClassPathName = "android/mtp/MtpDevice";
    428 
    429 int register_android_mtp_MtpDevice(JNIEnv *env)
    430 {
    431     jclass clazz;
    432 
    433     ALOGD("register_android_mtp_MtpDevice\n");
    434 
    435     clazz = env->FindClass("android/mtp/MtpDeviceInfo");
    436     if (clazz == NULL) {
    437         ALOGE("Can't find android/mtp/MtpDeviceInfo");
    438         return -1;
    439     }
    440     constructor_deviceInfo = env->GetMethodID(clazz, "<init>", "()V");
    441     if (constructor_deviceInfo == NULL) {
    442         ALOGE("Can't find android/mtp/MtpDeviceInfo constructor");
    443         return -1;
    444     }
    445     field_deviceInfo_manufacturer = env->GetFieldID(clazz, "mManufacturer", "Ljava/lang/String;");
    446     if (field_deviceInfo_manufacturer == NULL) {
    447         ALOGE("Can't find MtpDeviceInfo.mManufacturer");
    448         return -1;
    449     }
    450     field_deviceInfo_model = env->GetFieldID(clazz, "mModel", "Ljava/lang/String;");
    451     if (field_deviceInfo_model == NULL) {
    452         ALOGE("Can't find MtpDeviceInfo.mModel");
    453         return -1;
    454     }
    455     field_deviceInfo_version = env->GetFieldID(clazz, "mVersion", "Ljava/lang/String;");
    456     if (field_deviceInfo_version == NULL) {
    457         ALOGE("Can't find MtpDeviceInfo.mVersion");
    458         return -1;
    459     }
    460     field_deviceInfo_serialNumber = env->GetFieldID(clazz, "mSerialNumber", "Ljava/lang/String;");
    461     if (field_deviceInfo_serialNumber == NULL) {
    462         ALOGE("Can't find MtpDeviceInfo.mSerialNumber");
    463         return -1;
    464     }
    465     clazz_deviceInfo = (jclass)env->NewGlobalRef(clazz);
    466 
    467     clazz = env->FindClass("android/mtp/MtpStorageInfo");
    468     if (clazz == NULL) {
    469         ALOGE("Can't find android/mtp/MtpStorageInfo");
    470         return -1;
    471     }
    472     constructor_storageInfo = env->GetMethodID(clazz, "<init>", "()V");
    473     if (constructor_storageInfo == NULL) {
    474         ALOGE("Can't find android/mtp/MtpStorageInfo constructor");
    475         return -1;
    476     }
    477     field_storageInfo_storageId = env->GetFieldID(clazz, "mStorageId", "I");
    478     if (field_storageInfo_storageId == NULL) {
    479         ALOGE("Can't find MtpStorageInfo.mStorageId");
    480         return -1;
    481     }
    482     field_storageInfo_maxCapacity = env->GetFieldID(clazz, "mMaxCapacity", "J");
    483     if (field_storageInfo_maxCapacity == NULL) {
    484         ALOGE("Can't find MtpStorageInfo.mMaxCapacity");
    485         return -1;
    486     }
    487     field_storageInfo_freeSpace = env->GetFieldID(clazz, "mFreeSpace", "J");
    488     if (field_storageInfo_freeSpace == NULL) {
    489         ALOGE("Can't find MtpStorageInfo.mFreeSpace");
    490         return -1;
    491     }
    492     field_storageInfo_description = env->GetFieldID(clazz, "mDescription", "Ljava/lang/String;");
    493     if (field_storageInfo_description == NULL) {
    494         ALOGE("Can't find MtpStorageInfo.mDescription");
    495         return -1;
    496     }
    497     field_storageInfo_volumeIdentifier = env->GetFieldID(clazz, "mVolumeIdentifier", "Ljava/lang/String;");
    498     if (field_storageInfo_volumeIdentifier == NULL) {
    499         ALOGE("Can't find MtpStorageInfo.mVolumeIdentifier");
    500         return -1;
    501     }
    502     clazz_storageInfo = (jclass)env->NewGlobalRef(clazz);
    503 
    504     clazz = env->FindClass("android/mtp/MtpObjectInfo");
    505     if (clazz == NULL) {
    506         ALOGE("Can't find android/mtp/MtpObjectInfo");
    507         return -1;
    508     }
    509     constructor_objectInfo = env->GetMethodID(clazz, "<init>", "()V");
    510     if (constructor_objectInfo == NULL) {
    511         ALOGE("Can't find android/mtp/MtpObjectInfo constructor");
    512         return -1;
    513     }
    514     field_objectInfo_handle = env->GetFieldID(clazz, "mHandle", "I");
    515     if (field_objectInfo_handle == NULL) {
    516         ALOGE("Can't find MtpObjectInfo.mHandle");
    517         return -1;
    518     }
    519     field_objectInfo_storageId = env->GetFieldID(clazz, "mStorageId", "I");
    520     if (field_objectInfo_storageId == NULL) {
    521         ALOGE("Can't find MtpObjectInfo.mStorageId");
    522         return -1;
    523     }
    524     field_objectInfo_format = env->GetFieldID(clazz, "mFormat", "I");
    525     if (field_objectInfo_format == NULL) {
    526         ALOGE("Can't find MtpObjectInfo.mFormat");
    527         return -1;
    528     }
    529     field_objectInfo_protectionStatus = env->GetFieldID(clazz, "mProtectionStatus", "I");
    530     if (field_objectInfo_protectionStatus == NULL) {
    531         ALOGE("Can't find MtpObjectInfo.mProtectionStatus");
    532         return -1;
    533     }
    534     field_objectInfo_compressedSize = env->GetFieldID(clazz, "mCompressedSize", "I");
    535     if (field_objectInfo_compressedSize == NULL) {
    536         ALOGE("Can't find MtpObjectInfo.mCompressedSize");
    537         return -1;
    538     }
    539     field_objectInfo_thumbFormat = env->GetFieldID(clazz, "mThumbFormat", "I");
    540     if (field_objectInfo_thumbFormat == NULL) {
    541         ALOGE("Can't find MtpObjectInfo.mThumbFormat");
    542         return -1;
    543     }
    544     field_objectInfo_thumbCompressedSize = env->GetFieldID(clazz, "mThumbCompressedSize", "I");
    545     if (field_objectInfo_thumbCompressedSize == NULL) {
    546         ALOGE("Can't find MtpObjectInfo.mThumbCompressedSize");
    547         return -1;
    548     }
    549     field_objectInfo_thumbPixWidth = env->GetFieldID(clazz, "mThumbPixWidth", "I");
    550     if (field_objectInfo_thumbPixWidth == NULL) {
    551         ALOGE("Can't find MtpObjectInfo.mThumbPixWidth");
    552         return -1;
    553     }
    554     field_objectInfo_thumbPixHeight = env->GetFieldID(clazz, "mThumbPixHeight", "I");
    555     if (field_objectInfo_thumbPixHeight == NULL) {
    556         ALOGE("Can't find MtpObjectInfo.mThumbPixHeight");
    557         return -1;
    558     }
    559     field_objectInfo_imagePixWidth = env->GetFieldID(clazz, "mImagePixWidth", "I");
    560     if (field_objectInfo_imagePixWidth == NULL) {
    561         ALOGE("Can't find MtpObjectInfo.mImagePixWidth");
    562         return -1;
    563     }
    564     field_objectInfo_imagePixHeight = env->GetFieldID(clazz, "mImagePixHeight", "I");
    565     if (field_objectInfo_imagePixHeight == NULL) {
    566         ALOGE("Can't find MtpObjectInfo.mImagePixHeight");
    567         return -1;
    568     }
    569     field_objectInfo_imagePixDepth = env->GetFieldID(clazz, "mImagePixDepth", "I");
    570     if (field_objectInfo_imagePixDepth == NULL) {
    571         ALOGE("Can't find MtpObjectInfo.mImagePixDepth");
    572         return -1;
    573     }
    574     field_objectInfo_parent = env->GetFieldID(clazz, "mParent", "I");
    575     if (field_objectInfo_parent == NULL) {
    576         ALOGE("Can't find MtpObjectInfo.mParent");
    577         return -1;
    578     }
    579     field_objectInfo_associationType = env->GetFieldID(clazz, "mAssociationType", "I");
    580     if (field_objectInfo_associationType == NULL) {
    581         ALOGE("Can't find MtpObjectInfo.mAssociationType");
    582         return -1;
    583     }
    584     field_objectInfo_associationDesc = env->GetFieldID(clazz, "mAssociationDesc", "I");
    585     if (field_objectInfo_associationDesc == NULL) {
    586         ALOGE("Can't find MtpObjectInfo.mAssociationDesc");
    587         return -1;
    588     }
    589     field_objectInfo_sequenceNumber = env->GetFieldID(clazz, "mSequenceNumber", "I");
    590     if (field_objectInfo_sequenceNumber == NULL) {
    591         ALOGE("Can't find MtpObjectInfo.mSequenceNumber");
    592         return -1;
    593     }
    594     field_objectInfo_name = env->GetFieldID(clazz, "mName", "Ljava/lang/String;");
    595     if (field_objectInfo_name == NULL) {
    596         ALOGE("Can't find MtpObjectInfo.mName");
    597         return -1;
    598     }
    599     field_objectInfo_dateCreated = env->GetFieldID(clazz, "mDateCreated", "J");
    600     if (field_objectInfo_dateCreated == NULL) {
    601         ALOGE("Can't find MtpObjectInfo.mDateCreated");
    602         return -1;
    603     }
    604     field_objectInfo_dateModified = env->GetFieldID(clazz, "mDateModified", "J");
    605     if (field_objectInfo_dateModified == NULL) {
    606         ALOGE("Can't find MtpObjectInfo.mDateModified");
    607         return -1;
    608     }
    609     field_objectInfo_keywords = env->GetFieldID(clazz, "mKeywords", "Ljava/lang/String;");
    610     if (field_objectInfo_keywords == NULL) {
    611         ALOGE("Can't find MtpObjectInfo.mKeywords");
    612         return -1;
    613     }
    614     clazz_objectInfo = (jclass)env->NewGlobalRef(clazz);
    615 
    616     clazz = env->FindClass("android/mtp/MtpDevice");
    617     if (clazz == NULL) {
    618         ALOGE("Can't find android/mtp/MtpDevice");
    619         return -1;
    620     }
    621     field_context = env->GetFieldID(clazz, "mNativeContext", "I");
    622     if (field_context == NULL) {
    623         ALOGE("Can't find MtpDevice.mNativeContext");
    624         return -1;
    625     }
    626 
    627     return AndroidRuntime::registerNativeMethods(env,
    628                 "android/mtp/MtpDevice", gMethods, NELEM(gMethods));
    629 }
    630