android_view_InputChannel.cpp revision b93a03f841d93498bfea6cc92a22faa34bce1337 
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 <androidfw/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        ALOGW("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    if (inputChannelObj) {
115        android_view_InputChannel_setNativeInputChannel(env, inputChannelObj, nativeInputChannel);
116    }
117    return inputChannelObj;
118}
119
120static jobjectArray android_view_InputChannel_nativeOpenInputChannelPair(JNIEnv* env,
121        jclass clazz, jstring nameObj) {
122    const char* nameChars = env->GetStringUTFChars(nameObj, NULL);
123    String8 name(nameChars);
124    env->ReleaseStringUTFChars(nameObj, nameChars);
125
126    sp<InputChannel> serverChannel;
127    sp<InputChannel> clientChannel;
128    status_t result = InputChannel::openInputChannelPair(name, serverChannel, clientChannel);
129
130    if (result) {
131        String8 message;
132        message.appendFormat("Could not open input channel pair.  status=%d", result);
133        jniThrowRuntimeException(env, message.string());
134        return NULL;
135    }
136
137    jobjectArray channelPair = env->NewObjectArray(2, gInputChannelClassInfo.clazz, NULL);
138    if (env->ExceptionCheck()) {
139        return NULL;
140    }
141
142    jobject serverChannelObj = android_view_InputChannel_createInputChannel(env,
143            new NativeInputChannel(serverChannel));
144    if (env->ExceptionCheck()) {
145        return NULL;
146    }
147
148    jobject clientChannelObj = android_view_InputChannel_createInputChannel(env,
149            new NativeInputChannel(clientChannel));
150    if (env->ExceptionCheck()) {
151        return NULL;
152    }
153
154    env->SetObjectArrayElement(channelPair, 0, serverChannelObj);
155    env->SetObjectArrayElement(channelPair, 1, clientChannelObj);
156    return channelPair;
157}
158
159static void android_view_InputChannel_nativeDispose(JNIEnv* env, jobject obj, jboolean finalized) {
160    NativeInputChannel* nativeInputChannel =
161            android_view_InputChannel_getNativeInputChannel(env, obj);
162    if (nativeInputChannel) {
163        if (finalized) {
164            ALOGW("Input channel object '%s' was finalized without being disposed!",
165                    nativeInputChannel->getInputChannel()->getName().string());
166        }
167
168        nativeInputChannel->invokeAndRemoveDisposeCallback(env, obj);
169
170        android_view_InputChannel_setNativeInputChannel(env, obj, NULL);
171        delete nativeInputChannel;
172    }
173}
174
175static void android_view_InputChannel_nativeTransferTo(JNIEnv* env, jobject obj,
176        jobject otherObj) {
177    if (android_view_InputChannel_getNativeInputChannel(env, otherObj) != NULL) {
178        jniThrowException(env, "java/lang/IllegalStateException",
179                "Other object already has a native input channel.");
180        return;
181    }
182
183    NativeInputChannel* nativeInputChannel =
184            android_view_InputChannel_getNativeInputChannel(env, obj);
185    android_view_InputChannel_setNativeInputChannel(env, otherObj, nativeInputChannel);
186    android_view_InputChannel_setNativeInputChannel(env, obj, NULL);
187}
188
189static void android_view_InputChannel_nativeReadFromParcel(JNIEnv* env, jobject obj,
190        jobject parcelObj) {
191    if (android_view_InputChannel_getNativeInputChannel(env, obj) != NULL) {
192        jniThrowException(env, "java/lang/IllegalStateException",
193                "This object already has a native input channel.");
194        return;
195    }
196
197    Parcel* parcel = parcelForJavaObject(env, parcelObj);
198    if (parcel) {
199        bool isInitialized = parcel->readInt32();
200        if (isInitialized) {
201            String8 name = parcel->readString8();
202            int rawFd = parcel->readFileDescriptor();
203            int dupFd = dup(rawFd);
204            if (dupFd < 0) {
205                ALOGE("Error %d dup channel fd %d.", errno, rawFd);
206                jniThrowRuntimeException(env,
207                        "Could not read input channel file descriptors from parcel.");
208                return;
209            }
210
211            InputChannel* inputChannel = new InputChannel(name, dupFd);
212            NativeInputChannel* nativeInputChannel = new NativeInputChannel(inputChannel);
213
214            android_view_InputChannel_setNativeInputChannel(env, obj, nativeInputChannel);
215        }
216    }
217}
218
219static void android_view_InputChannel_nativeWriteToParcel(JNIEnv* env, jobject obj,
220        jobject parcelObj) {
221    Parcel* parcel = parcelForJavaObject(env, parcelObj);
222    if (parcel) {
223        NativeInputChannel* nativeInputChannel =
224                android_view_InputChannel_getNativeInputChannel(env, obj);
225        if (nativeInputChannel) {
226            sp<InputChannel> inputChannel = nativeInputChannel->getInputChannel();
227
228            parcel->writeInt32(1);
229            parcel->writeString8(inputChannel->getName());
230            parcel->writeDupFileDescriptor(inputChannel->getFd());
231        } else {
232            parcel->writeInt32(0);
233        }
234    }
235}
236
237static jstring android_view_InputChannel_nativeGetName(JNIEnv* env, jobject obj) {
238    NativeInputChannel* nativeInputChannel =
239            android_view_InputChannel_getNativeInputChannel(env, obj);
240    if (! nativeInputChannel) {
241        return NULL;
242    }
243
244    jstring name = env->NewStringUTF(nativeInputChannel->getInputChannel()->getName().string());
245    return name;
246}
247
248// ----------------------------------------------------------------------------
249
250static JNINativeMethod gInputChannelMethods[] = {
251    /* name, signature, funcPtr */
252    { "nativeOpenInputChannelPair", "(Ljava/lang/String;)[Landroid/view/InputChannel;",
253            (void*)android_view_InputChannel_nativeOpenInputChannelPair },
254    { "nativeDispose", "(Z)V",
255            (void*)android_view_InputChannel_nativeDispose },
256    { "nativeTransferTo", "(Landroid/view/InputChannel;)V",
257            (void*)android_view_InputChannel_nativeTransferTo },
258    { "nativeReadFromParcel", "(Landroid/os/Parcel;)V",
259            (void*)android_view_InputChannel_nativeReadFromParcel },
260    { "nativeWriteToParcel", "(Landroid/os/Parcel;)V",
261            (void*)android_view_InputChannel_nativeWriteToParcel },
262    { "nativeGetName", "()Ljava/lang/String;",
263            (void*)android_view_InputChannel_nativeGetName },
264};
265
266#define FIND_CLASS(var, className) \
267        var = env->FindClass(className); \
268        LOG_FATAL_IF(! var, "Unable to find class " className); \
269        var = jclass(env->NewGlobalRef(var));
270
271#define GET_METHOD_ID(var, clazz, methodName, methodDescriptor) \
272        var = env->GetMethodID(clazz, methodName, methodDescriptor); \
273        LOG_FATAL_IF(! var, "Unable to find method " methodName);
274
275#define GET_FIELD_ID(var, clazz, fieldName, fieldDescriptor) \
276        var = env->GetFieldID(clazz, fieldName, fieldDescriptor); \
277        LOG_FATAL_IF(! var, "Unable to find field " fieldName);
278
279int register_android_view_InputChannel(JNIEnv* env) {
280    int res = jniRegisterNativeMethods(env, "android/view/InputChannel",
281            gInputChannelMethods, NELEM(gInputChannelMethods));
282    LOG_FATAL_IF(res < 0, "Unable to register native methods.");
283
284    FIND_CLASS(gInputChannelClassInfo.clazz, "android/view/InputChannel");
285
286    GET_FIELD_ID(gInputChannelClassInfo.mPtr, gInputChannelClassInfo.clazz,
287            "mPtr", "I");
288
289    GET_METHOD_ID(gInputChannelClassInfo.ctor, gInputChannelClassInfo.clazz,
290            "<init>", "()V");
291
292    return 0;
293}
294
295} // namespace android
296