android_os_HwBinder.cpp revision 01f374c635f2f3595d4119f19d5c4eecdda698f9 
1/*
2 * Copyright (C) 2016 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#define LOG_TAG "android_os_HwBinder"
19#include <android-base/logging.h>
20
21#include "android_os_HwBinder.h"
22
23#include "android_os_HwParcel.h"
24#include "android_os_HwRemoteBinder.h"
25
26#include <JNIHelp.h>
27#include <android/hidl/manager/1.0/IServiceManager.h>
28#include <android/hidl/base/1.0/IBase.h>
29#include <android/hidl/base/1.0/BpHwBase.h>
30#include <android_runtime/AndroidRuntime.h>
31#include <hidl/ServiceManagement.h>
32#include <hidl/Status.h>
33#include <hidl/HidlTransportSupport.h>
34#include <hwbinder/ProcessState.h>
35#include <nativehelper/ScopedLocalRef.h>
36#include <vintf/parse_string.h>
37
38#include "core_jni_helpers.h"
39
40using android::AndroidRuntime;
41using android::hardware::hidl_vec;
42using android::hardware::hidl_string;
43template<typename T>
44using Return = android::hardware::Return<T>;
45
46#define PACKAGE_PATH    "android/os"
47#define CLASS_NAME      "HwBinder"
48#define CLASS_PATH      PACKAGE_PATH "/" CLASS_NAME
49
50namespace android {
51
52static jclass gArrayListClass;
53static struct {
54    jmethodID size;
55    jmethodID get;
56} gArrayListMethods;
57
58static jclass gErrorClass;
59
60static struct fields_t {
61    jfieldID contextID;
62    jmethodID onTransactID;
63} gFields;
64
65// static
66void JHwBinder::InitClass(JNIEnv *env) {
67    ScopedLocalRef<jclass> clazz(
68            env, FindClassOrDie(env, CLASS_PATH));
69
70    gFields.contextID =
71        GetFieldIDOrDie(env, clazz.get(), "mNativeContext", "J");
72
73    gFields.onTransactID =
74        GetMethodIDOrDie(
75                env,
76                clazz.get(),
77                "onTransact",
78                "(IL" PACKAGE_PATH "/HwParcel;L" PACKAGE_PATH "/HwParcel;I)V");
79}
80
81// static
82sp<JHwBinder> JHwBinder::SetNativeContext(
83        JNIEnv *env, jobject thiz, const sp<JHwBinder> &context) {
84    sp<JHwBinder> old =
85        (JHwBinder *)env->GetLongField(thiz, gFields.contextID);
86
87    if (context != NULL) {
88        context->incStrong(NULL /* id */);
89    }
90
91    if (old != NULL) {
92        old->decStrong(NULL /* id */);
93    }
94
95    env->SetLongField(thiz, gFields.contextID, (long)context.get());
96
97    return old;
98}
99
100// static
101sp<JHwBinder> JHwBinder::GetNativeContext(
102        JNIEnv *env, jobject thiz) {
103    return (JHwBinder *)env->GetLongField(thiz, gFields.contextID);
104}
105
106JHwBinder::JHwBinder(JNIEnv *env, jobject thiz) {
107    jclass clazz = env->GetObjectClass(thiz);
108    CHECK(clazz != NULL);
109
110    mClass = (jclass)env->NewGlobalRef(clazz);
111    mObject = env->NewWeakGlobalRef(thiz);
112}
113
114JHwBinder::~JHwBinder() {
115    JNIEnv *env = AndroidRuntime::getJNIEnv();
116
117    env->DeleteWeakGlobalRef(mObject);
118    mObject = NULL;
119
120    env->DeleteGlobalRef(mClass);
121    mClass = NULL;
122}
123
124status_t JHwBinder::onTransact(
125        uint32_t code,
126        const hardware::Parcel &data,
127        hardware::Parcel *reply,
128        uint32_t flags,
129        TransactCallback callback) {
130    JNIEnv *env = AndroidRuntime::getJNIEnv();
131    bool isOneway = (flags & TF_ONE_WAY) != 0;
132    ScopedLocalRef<jobject> replyObj(env, nullptr);
133    sp<JHwParcel> replyContext = nullptr;
134
135    ScopedLocalRef<jobject> requestObj(env, JHwParcel::NewObject(env));
136    JHwParcel::GetNativeContext(env, requestObj.get())->setParcel(
137            const_cast<hardware::Parcel *>(&data), false /* assumeOwnership */);
138
139
140    if (!isOneway) {
141        replyObj.reset(JHwParcel::NewObject(env));
142
143        replyContext = JHwParcel::GetNativeContext(env, replyObj.get());
144
145        replyContext->setParcel(reply, false /* assumeOwnership */);
146        replyContext->setTransactCallback(callback);
147    }
148
149    env->CallVoidMethod(
150            mObject,
151            gFields.onTransactID,
152            code,
153            requestObj.get(),
154            replyObj.get(),
155            flags);
156
157    if (env->ExceptionCheck()) {
158        jthrowable excep = env->ExceptionOccurred();
159        env->ExceptionDescribe();
160
161        if (env->IsInstanceOf(excep, gErrorClass)) {
162            /* It's an error */
163            LOG(ERROR) << "Forcefully exiting";
164            exit(1);
165        } else {
166            env->ExceptionClear();
167            LOG(ERROR) << "Uncaught exception!";
168        }
169
170        env->DeleteLocalRef(excep);
171    }
172
173    status_t err = OK;
174
175    if (!isOneway) {
176        if (!replyContext->wasSent()) {
177            // The implementation never finished the transaction.
178            err = UNKNOWN_ERROR;  // XXX special error code instead?
179
180            reply->setDataPosition(0 /* pos */);
181        }
182
183        // Release all temporary storage now that scatter-gather data
184        // has been consolidated, either by calling the TransactCallback,
185        // if wasSent() == true or clearing the reply parcel (setDataOffset above).
186        replyContext->getStorage()->release(env);
187
188        // We cannot permanently pass ownership of "data" and "reply" over to their
189        // Java object wrappers (we don't own them ourselves).
190        replyContext->setParcel(
191                NULL /* parcel */, false /* assumeOwnership */);
192
193    }
194
195    JHwParcel::GetNativeContext(env, requestObj.get())->setParcel(
196            NULL /* parcel */, false /* assumeOwnership */);
197
198    return err;
199}
200
201}  // namespace android
202
203////////////////////////////////////////////////////////////////////////////////
204
205using namespace android;
206
207static void releaseNativeContext(void *nativeContext) {
208    sp<JHwBinder> binder = (JHwBinder *)nativeContext;
209
210    if (binder != NULL) {
211        binder->decStrong(NULL /* id */);
212    }
213}
214
215static jlong JHwBinder_native_init(JNIEnv *env) {
216    JHwBinder::InitClass(env);
217
218    return reinterpret_cast<jlong>(&releaseNativeContext);
219}
220
221static void JHwBinder_native_setup(JNIEnv *env, jobject thiz) {
222    sp<JHwBinder> context = new JHwBinder(env, thiz);
223
224    JHwBinder::SetNativeContext(env, thiz, context);
225}
226
227static void JHwBinder_native_transact(
228        JNIEnv * /* env */,
229        jobject /* thiz */,
230        jint /* code */,
231        jobject /* requestObj */,
232        jobject /* replyObj */,
233        jint /* flags */) {
234    CHECK(!"Should not be here");
235}
236
237static void JHwBinder_native_registerService(
238        JNIEnv *env,
239        jobject thiz,
240        jobject interfaceChainArrayList,
241        jstring serviceNameObj) {
242    if (serviceNameObj == NULL) {
243        jniThrowException(env, "java/lang/NullPointerException", NULL);
244        return;
245    }
246
247    const char *serviceName = env->GetStringUTFChars(serviceNameObj, NULL);
248    if (serviceName == NULL) {
249        return;  // XXX exception already pending?
250    }
251
252    jint numInterfaces = env->CallIntMethod(interfaceChainArrayList,
253                                            gArrayListMethods.size);
254    hidl_string *strings = new hidl_string[numInterfaces];
255
256    for (jint i = 0; i < numInterfaces; i++) {
257        jstring strObj = static_cast<jstring>(
258            env->CallObjectMethod(interfaceChainArrayList,
259                                  gArrayListMethods.get,
260                                  i)
261        );
262        const char * str = env->GetStringUTFChars(strObj, nullptr);
263        strings[i] = hidl_string(str);
264        env->ReleaseStringUTFChars(strObj, str);
265    }
266
267    hidl_vec<hidl_string> interfaceChain;
268    interfaceChain.setToExternal(strings, numInterfaces, true /* shouldOwn */);
269
270    sp<hardware::IBinder> binder = JHwBinder::GetNativeContext(env, thiz);
271
272    /* TODO(b/33440494) this is not right */
273    sp<hidl::base::V1_0::IBase> base = new hidl::base::V1_0::BpHwBase(binder);
274
275    auto manager = hardware::defaultServiceManager();
276
277    if (manager == nullptr) {
278        LOG(ERROR) << "Could not get hwservicemanager.";
279        signalExceptionForError(env, UNKNOWN_ERROR, true /* canThrowRemoteException */);
280        return;
281    }
282
283    Return<bool> ret = manager->add(interfaceChain, serviceName, base);
284
285    env->ReleaseStringUTFChars(serviceNameObj, serviceName);
286    serviceName = NULL;
287
288    bool ok = ret.isOk() && ret;
289
290    if (ok) {
291        LOG(INFO) << "Starting thread pool.";
292        ::android::hardware::ProcessState::self()->startThreadPool();
293    }
294
295    signalExceptionForError(env, (ok ? OK : UNKNOWN_ERROR), true /* canThrowRemoteException */);
296}
297
298static jobject JHwBinder_native_getService(
299        JNIEnv *env,
300        jclass /* clazzObj */,
301        jstring ifaceNameObj,
302        jstring serviceNameObj) {
303
304    using ::android::vintf::operator<<;
305
306    if (ifaceNameObj == NULL) {
307        jniThrowException(env, "java/lang/NullPointerException", NULL);
308        return NULL;
309    }
310    if (serviceNameObj == NULL) {
311        jniThrowException(env, "java/lang/NullPointerException", NULL);
312        return NULL;
313    }
314
315    auto manager = hardware::defaultServiceManager();
316
317    if (manager == nullptr) {
318        LOG(ERROR) << "Could not get hwservicemanager.";
319        signalExceptionForError(env, UNKNOWN_ERROR, true /* canThrowRemoteException */);
320        return NULL;
321    }
322
323    const char *ifaceNameCStr = env->GetStringUTFChars(ifaceNameObj, NULL);
324    if (ifaceNameCStr == NULL) {
325        return NULL; // XXX exception already pending?
326    }
327    std::string ifaceName(ifaceNameCStr);
328    env->ReleaseStringUTFChars(ifaceNameObj, ifaceNameCStr);
329    ::android::hardware::hidl_string ifaceNameHStr;
330    ifaceNameHStr.setToExternal(ifaceName.c_str(), ifaceName.size());
331
332    const char *serviceNameCStr = env->GetStringUTFChars(serviceNameObj, NULL);
333    if (serviceNameCStr == NULL) {
334        return NULL; // XXX exception already pending?
335    }
336    std::string serviceName(serviceNameCStr);
337    env->ReleaseStringUTFChars(serviceNameObj, serviceNameCStr);
338    ::android::hardware::hidl_string serviceNameHStr;
339    serviceNameHStr.setToExternal(serviceName.c_str(), serviceName.size());
340
341    LOG(INFO) << "Looking for service "
342              << ifaceName
343              << "/"
344              << serviceName;
345
346    ::android::vintf::Transport transport =
347            ::android::hardware::getTransport(ifaceName);
348    if (   transport != ::android::vintf::Transport::EMPTY
349        && transport != ::android::vintf::Transport::HWBINDER) {
350        LOG(ERROR) << "service " << ifaceName << " declares transport method "
351                   << transport << " but framework expects "
352                   << ::android::vintf::Transport::HWBINDER;
353        signalExceptionForError(env, UNKNOWN_ERROR, true /* canThrowRemoteException */);
354        return NULL;
355    }
356
357    Return<sp<hidl::base::V1_0::IBase>> ret = manager->get(ifaceNameHStr, serviceNameHStr);
358
359    if (!ret.isOk()) {
360        signalExceptionForError(env, UNKNOWN_ERROR, true /* canThrowRemoteException */);
361        return NULL;
362    }
363
364    sp<hardware::IBinder> service = hardware::toBinder<
365            hidl::base::V1_0::IBase, hidl::base::V1_0::BpHwBase>(ret);
366
367    if (service == NULL) {
368        signalExceptionForError(env, NAME_NOT_FOUND);
369        return NULL;
370    }
371
372    LOG(INFO) << "Starting thread pool.";
373    ::android::hardware::ProcessState::self()->startThreadPool();
374
375    return JHwRemoteBinder::NewObject(env, service);
376}
377
378static JNINativeMethod gMethods[] = {
379    { "native_init", "()J", (void *)JHwBinder_native_init },
380    { "native_setup", "()V", (void *)JHwBinder_native_setup },
381
382    { "transact",
383        "(IL" PACKAGE_PATH "/HwParcel;L" PACKAGE_PATH "/HwParcel;I)V",
384        (void *)JHwBinder_native_transact },
385
386    { "registerService", "(Ljava/util/ArrayList;Ljava/lang/String;)V",
387        (void *)JHwBinder_native_registerService },
388
389    { "getService", "(Ljava/lang/String;Ljava/lang/String;)L" PACKAGE_PATH "/IHwBinder;",
390        (void *)JHwBinder_native_getService },
391};
392
393namespace android {
394
395int register_android_os_HwBinder(JNIEnv *env) {
396    jclass arrayListClass = FindClassOrDie(env, "java/util/ArrayList");
397    gArrayListClass = MakeGlobalRefOrDie(env, arrayListClass);
398    gArrayListMethods.size = GetMethodIDOrDie(env, arrayListClass, "size", "()I");
399    gArrayListMethods.get = GetMethodIDOrDie(env, arrayListClass, "get", "(I)Ljava/lang/Object;");
400
401    jclass errorClass = FindClassOrDie(env, "java/lang/Error");
402    gErrorClass = MakeGlobalRefOrDie(env, errorClass);
403
404    return RegisterMethodsOrDie(env, CLASS_PATH, gMethods, NELEM(gMethods));
405}
406
407}  // namespace android
408