android_os_HwBinder.cpp revision 0382be2f32a78c3ee5f1601bb0a4cef8ae9c0903 
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
132    ScopedLocalRef<jobject> requestObj(env, JHwParcel::NewObject(env));
133    JHwParcel::GetNativeContext(env, requestObj.get())->setParcel(
134            const_cast<hardware::Parcel *>(&data), false /* assumeOwnership */);
135
136    ScopedLocalRef<jobject> replyObj(env, JHwParcel::NewObject(env));
137
138    sp<JHwParcel> replyContext =
139        JHwParcel::GetNativeContext(env, replyObj.get());
140
141    replyContext->setParcel(reply, false /* assumeOwnership */);
142    replyContext->setTransactCallback(callback);
143
144    env->CallVoidMethod(
145            mObject,
146            gFields.onTransactID,
147            code,
148            requestObj.get(),
149            replyObj.get(),
150            flags);
151
152    if (env->ExceptionCheck()) {
153        jthrowable excep = env->ExceptionOccurred();
154        env->ExceptionDescribe();
155
156        if (env->IsInstanceOf(excep, gErrorClass)) {
157            /* It's an error */
158            LOG(ERROR) << "Forcefully exiting";
159            exit(1);
160        } else {
161            env->ExceptionClear();
162            LOG(ERROR) << "Uncaught exception!";
163        }
164
165        env->DeleteLocalRef(excep);
166    }
167
168    status_t err = OK;
169
170    if (!replyContext->wasSent()) {
171        // The implementation never finished the transaction.
172        err = UNKNOWN_ERROR;  // XXX special error code instead?
173
174        reply->setDataPosition(0 /* pos */);
175    }
176
177    // Release all temporary storage now that scatter-gather data
178    // has been consolidated, either by calling the TransactCallback,
179    // if wasSent() == true or clearing the reply parcel (setDataOffset above).
180    replyContext->getStorage()->release(env);
181
182    // We cannot permanently pass ownership of "data" and "reply" over to their
183    // Java object wrappers (we don't own them ourselves).
184
185    JHwParcel::GetNativeContext(env, requestObj.get())->setParcel(
186            NULL /* parcel */, false /* assumeOwnership */);
187
188    replyContext->setParcel(
189            NULL /* parcel */, false /* assumeOwnership */);
190
191    return err;
192}
193
194}  // namespace android
195
196////////////////////////////////////////////////////////////////////////////////
197
198using namespace android;
199
200static void releaseNativeContext(void *nativeContext) {
201    sp<JHwBinder> binder = (JHwBinder *)nativeContext;
202
203    if (binder != NULL) {
204        binder->decStrong(NULL /* id */);
205    }
206}
207
208static jlong JHwBinder_native_init(JNIEnv *env) {
209    JHwBinder::InitClass(env);
210
211    return reinterpret_cast<jlong>(&releaseNativeContext);
212}
213
214static void JHwBinder_native_setup(JNIEnv *env, jobject thiz) {
215    sp<JHwBinder> context = new JHwBinder(env, thiz);
216
217    JHwBinder::SetNativeContext(env, thiz, context);
218}
219
220static void JHwBinder_native_transact(
221        JNIEnv * /* env */,
222        jobject /* thiz */,
223        jint /* code */,
224        jobject /* requestObj */,
225        jobject /* replyObj */,
226        jint /* flags */) {
227    CHECK(!"Should not be here");
228}
229
230static void JHwBinder_native_registerService(
231        JNIEnv *env,
232        jobject thiz,
233        jobject interfaceChainArrayList,
234        jstring serviceNameObj) {
235    if (serviceNameObj == NULL) {
236        jniThrowException(env, "java/lang/NullPointerException", NULL);
237        return;
238    }
239
240    const char *serviceName = env->GetStringUTFChars(serviceNameObj, NULL);
241    if (serviceName == NULL) {
242        return;  // XXX exception already pending?
243    }
244
245    jint numInterfaces = env->CallIntMethod(interfaceChainArrayList,
246                                            gArrayListMethods.size);
247    hidl_string *strings = new hidl_string[numInterfaces];
248
249    for (jint i = 0; i < numInterfaces; i++) {
250        jstring strObj = static_cast<jstring>(
251            env->CallObjectMethod(interfaceChainArrayList,
252                                  gArrayListMethods.get,
253                                  i)
254        );
255        const char * str = env->GetStringUTFChars(strObj, nullptr);
256        strings[i] = hidl_string(str);
257        env->ReleaseStringUTFChars(strObj, str);
258    }
259
260    hidl_vec<hidl_string> interfaceChain;
261    interfaceChain.setToExternal(strings, numInterfaces, true /* shouldOwn */);
262
263    sp<hardware::IBinder> binder = JHwBinder::GetNativeContext(env, thiz);
264
265    /* TODO(b/33440494) this is not right */
266    sp<hidl::base::V1_0::IBase> base = new hidl::base::V1_0::BpHwBase(binder);
267
268    auto manager = hardware::defaultServiceManager();
269
270    if (manager == nullptr) {
271        LOG(ERROR) << "Could not get hwservicemanager.";
272        signalExceptionForError(env, UNKNOWN_ERROR, true /* canThrowRemoteException */);
273        return;
274    }
275
276    Return<bool> ret = manager->add(interfaceChain, serviceName, base);
277
278    env->ReleaseStringUTFChars(serviceNameObj, serviceName);
279    serviceName = NULL;
280
281    bool ok = ret.isOk() && ret;
282
283    if (ok) {
284        LOG(INFO) << "Starting thread pool.";
285        ::android::hardware::ProcessState::self()->startThreadPool();
286    }
287
288    signalExceptionForError(env, (ok ? OK : UNKNOWN_ERROR), true /* canThrowRemoteException */);
289}
290
291static jobject JHwBinder_native_getService(
292        JNIEnv *env,
293        jclass /* clazzObj */,
294        jstring ifaceNameObj,
295        jstring serviceNameObj) {
296
297    using ::android::vintf::operator<<;
298
299    if (ifaceNameObj == NULL) {
300        jniThrowException(env, "java/lang/NullPointerException", NULL);
301        return NULL;
302    }
303    if (serviceNameObj == NULL) {
304        jniThrowException(env, "java/lang/NullPointerException", NULL);
305        return NULL;
306    }
307
308    auto manager = hardware::defaultServiceManager();
309
310    if (manager == nullptr) {
311        LOG(ERROR) << "Could not get hwservicemanager.";
312        signalExceptionForError(env, UNKNOWN_ERROR, true /* canThrowRemoteException */);
313        return NULL;
314    }
315
316    const char *ifaceNameCStr = env->GetStringUTFChars(ifaceNameObj, NULL);
317    if (ifaceNameCStr == NULL) {
318        return NULL; // XXX exception already pending?
319    }
320    std::string ifaceName(ifaceNameCStr);
321    env->ReleaseStringUTFChars(ifaceNameObj, ifaceNameCStr);
322    ::android::hardware::hidl_string ifaceNameHStr;
323    ifaceNameHStr.setToExternal(ifaceName.c_str(), ifaceName.size());
324
325    const char *serviceNameCStr = env->GetStringUTFChars(serviceNameObj, NULL);
326    if (serviceNameCStr == NULL) {
327        return NULL; // XXX exception already pending?
328    }
329    std::string serviceName(serviceNameCStr);
330    env->ReleaseStringUTFChars(serviceNameObj, serviceNameCStr);
331    ::android::hardware::hidl_string serviceNameHStr;
332    serviceNameHStr.setToExternal(serviceName.c_str(), serviceName.size());
333
334    LOG(INFO) << "Looking for service "
335              << ifaceName
336              << "/"
337              << serviceName;
338
339    ::android::vintf::Transport transport =
340            ::android::hardware::getTransport(ifaceName);
341    if (   transport != ::android::vintf::Transport::EMPTY
342        && transport != ::android::vintf::Transport::HWBINDER) {
343        LOG(ERROR) << "service " << ifaceName << " declares transport method "
344                   << transport << " but framework expects "
345                   << ::android::vintf::Transport::HWBINDER;
346        signalExceptionForError(env, UNKNOWN_ERROR, true /* canThrowRemoteException */);
347        return NULL;
348    }
349
350    Return<sp<hidl::base::V1_0::IBase>> ret = manager->get(ifaceNameHStr, serviceNameHStr);
351
352    if (!ret.isOk()) {
353        signalExceptionForError(env, UNKNOWN_ERROR, true /* canThrowRemoteException */);
354        return NULL;
355    }
356
357    sp<hardware::IBinder> service = hardware::toBinder<
358            hidl::base::V1_0::IBase, hidl::base::V1_0::BpHwBase>(ret);
359
360    if (service == NULL) {
361        signalExceptionForError(env, NAME_NOT_FOUND);
362        return NULL;
363    }
364
365    LOG(INFO) << "Starting thread pool.";
366    ::android::hardware::ProcessState::self()->startThreadPool();
367
368    return JHwRemoteBinder::NewObject(env, service);
369}
370
371static JNINativeMethod gMethods[] = {
372    { "native_init", "()J", (void *)JHwBinder_native_init },
373    { "native_setup", "()V", (void *)JHwBinder_native_setup },
374
375    { "transact",
376        "(IL" PACKAGE_PATH "/HwParcel;L" PACKAGE_PATH "/HwParcel;I)V",
377        (void *)JHwBinder_native_transact },
378
379    { "registerService", "(Ljava/util/ArrayList;Ljava/lang/String;)V",
380        (void *)JHwBinder_native_registerService },
381
382    { "getService", "(Ljava/lang/String;Ljava/lang/String;)L" PACKAGE_PATH "/IHwBinder;",
383        (void *)JHwBinder_native_getService },
384};
385
386namespace android {
387
388int register_android_os_HwBinder(JNIEnv *env) {
389    jclass arrayListClass = FindClassOrDie(env, "java/util/ArrayList");
390    gArrayListClass = MakeGlobalRefOrDie(env, arrayListClass);
391    gArrayListMethods.size = GetMethodIDOrDie(env, arrayListClass, "size", "()I");
392    gArrayListMethods.get = GetMethodIDOrDie(env, arrayListClass, "get", "(I)Ljava/lang/Object;");
393
394    jclass errorClass = FindClassOrDie(env, "java/lang/Error");
395    gErrorClass = MakeGlobalRefOrDie(env, errorClass);
396
397    return RegisterMethodsOrDie(env, CLASS_PATH, gMethods, NELEM(gMethods));
398}
399
400}  // namespace android
401