android_view_InputChannel.cpp revision 5c225b1680e696ae8bbf505a1997d6f720672f74 
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 <ui/InputTransport.h>
25#include "android_view_InputChannel.h"
26#include "android_util_Binder.h"
27
28namespace android {
29
30// ----------------------------------------------------------------------------
31
32static struct {
33    jclass clazz;
34
35    jfieldID mPtr;   // native object attached to the DVM InputChannel
36    jmethodID ctor;
37} gInputChannelClassInfo;
38
39// ----------------------------------------------------------------------------
40
41class NativeInputChannel {
42public:
43    NativeInputChannel(const sp<InputChannel>& inputChannel);
44    ~NativeInputChannel();
45
46    inline sp<InputChannel> getInputChannel() { return mInputChannel; }
47
48    void setDisposeCallback(InputChannelObjDisposeCallback callback, void* data);
49    void invokeAndRemoveDisposeCallback(JNIEnv* env, jobject obj);
50
51private:
52    sp<InputChannel> mInputChannel;
53    InputChannelObjDisposeCallback mDisposeCallback;
54    void* mDisposeData;
55};
56
57// ----------------------------------------------------------------------------
58
59NativeInputChannel::NativeInputChannel(const sp<InputChannel>& inputChannel) :
60    mInputChannel(inputChannel), mDisposeCallback(NULL) {
61}
62
63NativeInputChannel::~NativeInputChannel() {
64}
65
66void NativeInputChannel::setDisposeCallback(InputChannelObjDisposeCallback callback, void* data) {
67    mDisposeCallback = callback;
68    mDisposeData = data;
69}
70
71void NativeInputChannel::invokeAndRemoveDisposeCallback(JNIEnv* env, jobject obj) {
72    if (mDisposeCallback) {
73        mDisposeCallback(env, obj, mInputChannel, mDisposeData);
74        mDisposeCallback = NULL;
75        mDisposeData = NULL;
76    }
77}
78
79// ----------------------------------------------------------------------------
80
81static NativeInputChannel* android_view_InputChannel_getNativeInputChannel(JNIEnv* env,
82        jobject inputChannelObj) {
83    jint intPtr = env->GetIntField(inputChannelObj, gInputChannelClassInfo.mPtr);
84    return reinterpret_cast<NativeInputChannel*>(intPtr);
85}
86
87static void android_view_InputChannel_setNativeInputChannel(JNIEnv* env, jobject inputChannelObj,
88        NativeInputChannel* nativeInputChannel) {
89    env->SetIntField(inputChannelObj, gInputChannelClassInfo.mPtr,
90             reinterpret_cast<jint>(nativeInputChannel));
91}
92
93sp<InputChannel> android_view_InputChannel_getInputChannel(JNIEnv* env, jobject inputChannelObj) {
94    NativeInputChannel* nativeInputChannel =
95            android_view_InputChannel_getNativeInputChannel(env, inputChannelObj);
96    return nativeInputChannel != NULL ? nativeInputChannel->getInputChannel() : NULL;
97}
98
99void android_view_InputChannel_setDisposeCallback(JNIEnv* env, jobject inputChannelObj,
100        InputChannelObjDisposeCallback callback, void* data) {
101    NativeInputChannel* nativeInputChannel =
102            android_view_InputChannel_getNativeInputChannel(env, inputChannelObj);
103    if (nativeInputChannel == NULL) {
104        LOGW("Cannot set dispose callback because input channel object has not been initialized.");
105    } else {
106        nativeInputChannel->setDisposeCallback(callback, data);
107    }
108}
109
110static jobject android_view_InputChannel_createInputChannel(JNIEnv* env,
111        NativeInputChannel* nativeInputChannel) {
112    jobject inputChannelObj = env->NewObject(gInputChannelClassInfo.clazz,
113            gInputChannelClassInfo.ctor);
114    android_view_InputChannel_setNativeInputChannel(env, inputChannelObj, nativeInputChannel);
115    return inputChannelObj;
116}
117
118static jobjectArray android_view_InputChannel_nativeOpenInputChannelPair(JNIEnv* env,
119        jclass clazz, jstring nameObj) {
120    const char* nameChars = env->GetStringUTFChars(nameObj, NULL);
121    String8 name(nameChars);
122    env->ReleaseStringUTFChars(nameObj, nameChars);
123
124    sp<InputChannel> serverChannel;
125    sp<InputChannel> clientChannel;
126    status_t result = InputChannel::openInputChannelPair(name, serverChannel, clientChannel);
127
128    if (result) {
129        LOGE("Could not open input channel pair.  status=%d", result);
130        jniThrowRuntimeException(env, "Could not open input channel pair.");
131        return NULL;
132    }
133
134    // TODO more robust error checking
135    jobject serverChannelObj = android_view_InputChannel_createInputChannel(env,
136            new NativeInputChannel(serverChannel));
137    jobject clientChannelObj = android_view_InputChannel_createInputChannel(env,
138            new NativeInputChannel(clientChannel));
139
140    jobjectArray channelPair = env->NewObjectArray(2, gInputChannelClassInfo.clazz, NULL);
141    env->SetObjectArrayElement(channelPair, 0, serverChannelObj);
142    env->SetObjectArrayElement(channelPair, 1, clientChannelObj);
143    return channelPair;
144}
145
146static void android_view_InputChannel_nativeDispose(JNIEnv* env, jobject obj, jboolean finalized) {
147    NativeInputChannel* nativeInputChannel =
148            android_view_InputChannel_getNativeInputChannel(env, obj);
149    if (nativeInputChannel) {
150        if (finalized) {
151            LOGW("Input channel object '%s' was finalized without being disposed!",
152                    nativeInputChannel->getInputChannel()->getName().string());
153        }
154
155        nativeInputChannel->invokeAndRemoveDisposeCallback(env, obj);
156
157        android_view_InputChannel_setNativeInputChannel(env, obj, NULL);
158        delete nativeInputChannel;
159    }
160}
161
162static void android_view_InputChannel_nativeTransferTo(JNIEnv* env, jobject obj,
163        jobject otherObj) {
164    if (android_view_InputChannel_getInputChannel(env, otherObj) != NULL) {
165        jniThrowException(env, "java/lang/IllegalStateException",
166                "Other object already has a native input channel.");
167        return;
168    }
169
170    NativeInputChannel* nativeInputChannel =
171            android_view_InputChannel_getNativeInputChannel(env, obj);
172    android_view_InputChannel_setNativeInputChannel(env, otherObj, nativeInputChannel);
173    android_view_InputChannel_setNativeInputChannel(env, obj, NULL);
174}
175
176static void android_view_InputChannel_nativeReadFromParcel(JNIEnv* env, jobject obj,
177        jobject parcelObj) {
178    if (android_view_InputChannel_getInputChannel(env, obj) != NULL) {
179        jniThrowException(env, "java/lang/IllegalStateException",
180                "This object already has a native input channel.");
181        return;
182    }
183
184    Parcel* parcel = parcelForJavaObject(env, parcelObj);
185    if (parcel) {
186        bool isInitialized = parcel->readInt32();
187        if (isInitialized) {
188            String8 name = parcel->readString8();
189            int32_t ashmemFd = dup(parcel->readFileDescriptor());
190            int32_t receivePipeFd = dup(parcel->readFileDescriptor());
191            int32_t sendPipeFd = dup(parcel->readFileDescriptor());
192            if (ashmemFd < 0 || receivePipeFd < 0 || sendPipeFd < 0) {
193                if (ashmemFd >= 0) ::close(ashmemFd);
194                if (receivePipeFd >= 0) ::close(receivePipeFd);
195                if (sendPipeFd >= 0) ::close(sendPipeFd);
196                jniThrowRuntimeException(env,
197                        "Could not read input channel file descriptors from parcel.");
198                return;
199            }
200
201            InputChannel* inputChannel = new InputChannel(name, ashmemFd,
202                    receivePipeFd, sendPipeFd);
203            NativeInputChannel* nativeInputChannel = new NativeInputChannel(inputChannel);
204
205            android_view_InputChannel_setNativeInputChannel(env, obj, nativeInputChannel);
206        }
207    }
208}
209
210static void android_view_InputChannel_nativeWriteToParcel(JNIEnv* env, jobject obj,
211        jobject parcelObj) {
212    Parcel* parcel = parcelForJavaObject(env, parcelObj);
213    if (parcel) {
214        NativeInputChannel* nativeInputChannel =
215                android_view_InputChannel_getNativeInputChannel(env, obj);
216        if (nativeInputChannel) {
217            sp<InputChannel> inputChannel = nativeInputChannel->getInputChannel();
218
219            parcel->writeInt32(1);
220            parcel->writeString8(inputChannel->getName());
221            parcel->writeDupFileDescriptor(inputChannel->getAshmemFd());
222            parcel->writeDupFileDescriptor(inputChannel->getReceivePipeFd());
223            parcel->writeDupFileDescriptor(inputChannel->getSendPipeFd());
224        } else {
225            parcel->writeInt32(0);
226        }
227    }
228}
229
230static jstring android_view_InputChannel_nativeGetName(JNIEnv* env, jobject obj) {
231    NativeInputChannel* nativeInputChannel =
232            android_view_InputChannel_getNativeInputChannel(env, obj);
233    if (! nativeInputChannel) {
234        return NULL;
235    }
236
237    jstring name = env->NewStringUTF(nativeInputChannel->getInputChannel()->getName().string());
238    return name;
239}
240
241// ----------------------------------------------------------------------------
242
243static JNINativeMethod gInputChannelMethods[] = {
244    /* name, signature, funcPtr */
245    { "nativeOpenInputChannelPair", "(Ljava/lang/String;)[Landroid/view/InputChannel;",
246            (void*)android_view_InputChannel_nativeOpenInputChannelPair },
247    { "nativeDispose", "(Z)V",
248            (void*)android_view_InputChannel_nativeDispose },
249    { "nativeTransferTo", "(Landroid/view/InputChannel;)V",
250            (void*)android_view_InputChannel_nativeTransferTo },
251    { "nativeReadFromParcel", "(Landroid/os/Parcel;)V",
252            (void*)android_view_InputChannel_nativeReadFromParcel },
253    { "nativeWriteToParcel", "(Landroid/os/Parcel;)V",
254            (void*)android_view_InputChannel_nativeWriteToParcel },
255    { "nativeGetName", "()Ljava/lang/String;",
256            (void*)android_view_InputChannel_nativeGetName },
257};
258
259#define FIND_CLASS(var, className) \
260        var = env->FindClass(className); \
261        LOG_FATAL_IF(! var, "Unable to find class " className); \
262        var = jclass(env->NewGlobalRef(var));
263
264#define GET_METHOD_ID(var, clazz, methodName, methodDescriptor) \
265        var = env->GetMethodID(clazz, methodName, methodDescriptor); \
266        LOG_FATAL_IF(! var, "Unable to find method " methodName);
267
268#define GET_FIELD_ID(var, clazz, fieldName, fieldDescriptor) \
269        var = env->GetFieldID(clazz, fieldName, fieldDescriptor); \
270        LOG_FATAL_IF(! var, "Unable to find field " fieldName);
271
272int register_android_view_InputChannel(JNIEnv* env) {
273    int res = jniRegisterNativeMethods(env, "android/view/InputChannel",
274            gInputChannelMethods, NELEM(gInputChannelMethods));
275    LOG_FATAL_IF(res < 0, "Unable to register native methods.");
276
277    FIND_CLASS(gInputChannelClassInfo.clazz, "android/view/InputChannel");
278
279    GET_FIELD_ID(gInputChannelClassInfo.mPtr, gInputChannelClassInfo.clazz,
280            "mPtr", "I");
281
282    GET_METHOD_ID(gInputChannelClassInfo.ctor, gInputChannelClassInfo.clazz,
283            "<init>", "()V");
284
285    return 0;
286}
287
288} // namespace android
289