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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_TAG "InputChannel-JNI"
     18 
     19 #include "JNIHelp.h"
     20 
     21 #include <android_runtime/AndroidRuntime.h>
     22 #include <binder/Parcel.h>
     23 #include <utils/Log.h>
     24 #include <input/InputTransport.h>
     25 #include "android_view_InputChannel.h"
     26 #include "android_os_Parcel.h"
     27 #include "android_util_Binder.h"
     28 
     29 namespace android {
     30 
     31 // ----------------------------------------------------------------------------
     32 
     33 static struct {
     34     jclass clazz;
     35 
     36     jfieldID mPtr;   // native object attached to the DVM InputChannel
     37     jmethodID ctor;
     38 } gInputChannelClassInfo;
     39 
     40 // ----------------------------------------------------------------------------
     41 
     42 class NativeInputChannel {
     43 public:
     44     NativeInputChannel(const sp<InputChannel>& inputChannel);
     45     ~NativeInputChannel();
     46 
     47     inline sp<InputChannel> getInputChannel() { return mInputChannel; }
     48 
     49     void setDisposeCallback(InputChannelObjDisposeCallback callback, void* data);
     50     void invokeAndRemoveDisposeCallback(JNIEnv* env, jobject obj);
     51 
     52 private:
     53     sp<InputChannel> mInputChannel;
     54     InputChannelObjDisposeCallback mDisposeCallback;
     55     void* mDisposeData;
     56 };
     57 
     58 // ----------------------------------------------------------------------------
     59 
     60 NativeInputChannel::NativeInputChannel(const sp<InputChannel>& inputChannel) :
     61     mInputChannel(inputChannel), mDisposeCallback(NULL) {
     62 }
     63 
     64 NativeInputChannel::~NativeInputChannel() {
     65 }
     66 
     67 void NativeInputChannel::setDisposeCallback(InputChannelObjDisposeCallback callback, void* data) {
     68     mDisposeCallback = callback;
     69     mDisposeData = data;
     70 }
     71 
     72 void NativeInputChannel::invokeAndRemoveDisposeCallback(JNIEnv* env, jobject obj) {
     73     if (mDisposeCallback) {
     74         mDisposeCallback(env, obj, mInputChannel, mDisposeData);
     75         mDisposeCallback = NULL;
     76         mDisposeData = NULL;
     77     }
     78 }
     79 
     80 // ----------------------------------------------------------------------------
     81 
     82 static NativeInputChannel* android_view_InputChannel_getNativeInputChannel(JNIEnv* env,
     83         jobject inputChannelObj) {
     84     jlong longPtr = env->GetLongField(inputChannelObj, gInputChannelClassInfo.mPtr);
     85     return reinterpret_cast<NativeInputChannel*>(longPtr);
     86 }
     87 
     88 static void android_view_InputChannel_setNativeInputChannel(JNIEnv* env, jobject inputChannelObj,
     89         NativeInputChannel* nativeInputChannel) {
     90     env->SetLongField(inputChannelObj, gInputChannelClassInfo.mPtr,
     91              reinterpret_cast<jlong>(nativeInputChannel));
     92 }
     93 
     94 sp<InputChannel> android_view_InputChannel_getInputChannel(JNIEnv* env, jobject inputChannelObj) {
     95     NativeInputChannel* nativeInputChannel =
     96             android_view_InputChannel_getNativeInputChannel(env, inputChannelObj);
     97     return nativeInputChannel != NULL ? nativeInputChannel->getInputChannel() : NULL;
     98 }
     99 
    100 void android_view_InputChannel_setDisposeCallback(JNIEnv* env, jobject inputChannelObj,
    101         InputChannelObjDisposeCallback callback, void* data) {
    102     NativeInputChannel* nativeInputChannel =
    103             android_view_InputChannel_getNativeInputChannel(env, inputChannelObj);
    104     if (nativeInputChannel == NULL) {
    105         ALOGW("Cannot set dispose callback because input channel object has not been initialized.");
    106     } else {
    107         nativeInputChannel->setDisposeCallback(callback, data);
    108     }
    109 }
    110 
    111 static jobject android_view_InputChannel_createInputChannel(JNIEnv* env,
    112         NativeInputChannel* nativeInputChannel) {
    113     jobject inputChannelObj = env->NewObject(gInputChannelClassInfo.clazz,
    114             gInputChannelClassInfo.ctor);
    115     if (inputChannelObj) {
    116         android_view_InputChannel_setNativeInputChannel(env, inputChannelObj, nativeInputChannel);
    117     }
    118     return inputChannelObj;
    119 }
    120 
    121 static jobjectArray android_view_InputChannel_nativeOpenInputChannelPair(JNIEnv* env,
    122         jclass clazz, jstring nameObj) {
    123     const char* nameChars = env->GetStringUTFChars(nameObj, NULL);
    124     String8 name(nameChars);
    125     env->ReleaseStringUTFChars(nameObj, nameChars);
    126 
    127     sp<InputChannel> serverChannel;
    128     sp<InputChannel> clientChannel;
    129     status_t result = InputChannel::openInputChannelPair(name, serverChannel, clientChannel);
    130 
    131     if (result) {
    132         String8 message;
    133         message.appendFormat("Could not open input channel pair.  status=%d", result);
    134         jniThrowRuntimeException(env, message.string());
    135         return NULL;
    136     }
    137 
    138     jobjectArray channelPair = env->NewObjectArray(2, gInputChannelClassInfo.clazz, NULL);
    139     if (env->ExceptionCheck()) {
    140         return NULL;
    141     }
    142 
    143     jobject serverChannelObj = android_view_InputChannel_createInputChannel(env,
    144             new NativeInputChannel(serverChannel));
    145     if (env->ExceptionCheck()) {
    146         return NULL;
    147     }
    148 
    149     jobject clientChannelObj = android_view_InputChannel_createInputChannel(env,
    150             new NativeInputChannel(clientChannel));
    151     if (env->ExceptionCheck()) {
    152         return NULL;
    153     }
    154 
    155     env->SetObjectArrayElement(channelPair, 0, serverChannelObj);
    156     env->SetObjectArrayElement(channelPair, 1, clientChannelObj);
    157     return channelPair;
    158 }
    159 
    160 static void android_view_InputChannel_nativeDispose(JNIEnv* env, jobject obj, jboolean finalized) {
    161     NativeInputChannel* nativeInputChannel =
    162             android_view_InputChannel_getNativeInputChannel(env, obj);
    163     if (nativeInputChannel) {
    164         if (finalized) {
    165             ALOGW("Input channel object '%s' was finalized without being disposed!",
    166                     nativeInputChannel->getInputChannel()->getName().string());
    167         }
    168 
    169         nativeInputChannel->invokeAndRemoveDisposeCallback(env, obj);
    170 
    171         android_view_InputChannel_setNativeInputChannel(env, obj, NULL);
    172         delete nativeInputChannel;
    173     }
    174 }
    175 
    176 static void android_view_InputChannel_nativeTransferTo(JNIEnv* env, jobject obj,
    177         jobject otherObj) {
    178     if (android_view_InputChannel_getNativeInputChannel(env, otherObj) != NULL) {
    179         jniThrowException(env, "java/lang/IllegalStateException",
    180                 "Other object already has a native input channel.");
    181         return;
    182     }
    183 
    184     NativeInputChannel* nativeInputChannel =
    185             android_view_InputChannel_getNativeInputChannel(env, obj);
    186     android_view_InputChannel_setNativeInputChannel(env, otherObj, nativeInputChannel);
    187     android_view_InputChannel_setNativeInputChannel(env, obj, NULL);
    188 }
    189 
    190 static void android_view_InputChannel_nativeReadFromParcel(JNIEnv* env, jobject obj,
    191         jobject parcelObj) {
    192     if (android_view_InputChannel_getNativeInputChannel(env, obj) != NULL) {
    193         jniThrowException(env, "java/lang/IllegalStateException",
    194                 "This object already has a native input channel.");
    195         return;
    196     }
    197 
    198     Parcel* parcel = parcelForJavaObject(env, parcelObj);
    199     if (parcel) {
    200         bool isInitialized = parcel->readInt32();
    201         if (isInitialized) {
    202             String8 name = parcel->readString8();
    203             int rawFd = parcel->readFileDescriptor();
    204             int dupFd = dup(rawFd);
    205             if (dupFd < 0) {
    206                 ALOGE("Error %d dup channel fd %d.", errno, rawFd);
    207                 jniThrowRuntimeException(env,
    208                         "Could not read input channel file descriptors from parcel.");
    209                 return;
    210             }
    211 
    212             InputChannel* inputChannel = new InputChannel(name, dupFd);
    213             NativeInputChannel* nativeInputChannel = new NativeInputChannel(inputChannel);
    214 
    215             android_view_InputChannel_setNativeInputChannel(env, obj, nativeInputChannel);
    216         }
    217     }
    218 }
    219 
    220 static void android_view_InputChannel_nativeWriteToParcel(JNIEnv* env, jobject obj,
    221         jobject parcelObj) {
    222     Parcel* parcel = parcelForJavaObject(env, parcelObj);
    223     if (parcel) {
    224         NativeInputChannel* nativeInputChannel =
    225                 android_view_InputChannel_getNativeInputChannel(env, obj);
    226         if (nativeInputChannel) {
    227             sp<InputChannel> inputChannel = nativeInputChannel->getInputChannel();
    228 
    229             parcel->writeInt32(1);
    230             parcel->writeString8(inputChannel->getName());
    231             parcel->writeDupFileDescriptor(inputChannel->getFd());
    232         } else {
    233             parcel->writeInt32(0);
    234         }
    235     }
    236 }
    237 
    238 static jstring android_view_InputChannel_nativeGetName(JNIEnv* env, jobject obj) {
    239     NativeInputChannel* nativeInputChannel =
    240             android_view_InputChannel_getNativeInputChannel(env, obj);
    241     if (! nativeInputChannel) {
    242         return NULL;
    243     }
    244 
    245     jstring name = env->NewStringUTF(nativeInputChannel->getInputChannel()->getName().string());
    246     return name;
    247 }
    248 
    249 static void android_view_InputChannel_nativeDup(JNIEnv* env, jobject obj, jobject otherObj) {
    250     NativeInputChannel* nativeInputChannel =
    251             android_view_InputChannel_getNativeInputChannel(env, obj);
    252     if (nativeInputChannel) {
    253         android_view_InputChannel_setNativeInputChannel(env, otherObj,
    254                 new NativeInputChannel(nativeInputChannel->getInputChannel()->dup()));
    255     }
    256 }
    257 
    258 // ----------------------------------------------------------------------------
    259 
    260 static JNINativeMethod gInputChannelMethods[] = {
    261     /* name, signature, funcPtr */
    262     { "nativeOpenInputChannelPair", "(Ljava/lang/String;)[Landroid/view/InputChannel;",
    263             (void*)android_view_InputChannel_nativeOpenInputChannelPair },
    264     { "nativeDispose", "(Z)V",
    265             (void*)android_view_InputChannel_nativeDispose },
    266     { "nativeTransferTo", "(Landroid/view/InputChannel;)V",
    267             (void*)android_view_InputChannel_nativeTransferTo },
    268     { "nativeReadFromParcel", "(Landroid/os/Parcel;)V",
    269             (void*)android_view_InputChannel_nativeReadFromParcel },
    270     { "nativeWriteToParcel", "(Landroid/os/Parcel;)V",
    271             (void*)android_view_InputChannel_nativeWriteToParcel },
    272     { "nativeGetName", "()Ljava/lang/String;",
    273             (void*)android_view_InputChannel_nativeGetName },
    274     { "nativeDup", "(Landroid/view/InputChannel;)V",
    275             (void*)android_view_InputChannel_nativeDup },
    276 };
    277 
    278 #define FIND_CLASS(var, className) \
    279         var = env->FindClass(className); \
    280         LOG_FATAL_IF(! var, "Unable to find class " className); \
    281         var = jclass(env->NewGlobalRef(var));
    282 
    283 #define GET_METHOD_ID(var, clazz, methodName, methodDescriptor) \
    284         var = env->GetMethodID(clazz, methodName, methodDescriptor); \
    285         LOG_FATAL_IF(! var, "Unable to find method " methodName);
    286 
    287 #define GET_FIELD_ID(var, clazz, fieldName, fieldDescriptor) \
    288         var = env->GetFieldID(clazz, fieldName, fieldDescriptor); \
    289         LOG_FATAL_IF(! var, "Unable to find field " fieldName);
    290 
    291 int register_android_view_InputChannel(JNIEnv* env) {
    292     int res = jniRegisterNativeMethods(env, "android/view/InputChannel",
    293             gInputChannelMethods, NELEM(gInputChannelMethods));
    294     LOG_FATAL_IF(res < 0, "Unable to register native methods.");
    295 
    296     FIND_CLASS(gInputChannelClassInfo.clazz, "android/view/InputChannel");
    297 
    298     GET_FIELD_ID(gInputChannelClassInfo.mPtr, gInputChannelClassInfo.clazz,
    299             "mPtr", "J");
    300 
    301     GET_METHOD_ID(gInputChannelClassInfo.ctor, gInputChannelClassInfo.clazz,
    302             "<init>", "()V");
    303 
    304     return 0;
    305 }
    306 
    307 } // namespace android
    308