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