IPCThreadState.cpp revision 2b6317436d2035ce98331906aaaca87e6026c9c8 
1/*
2 * Copyright (C) 2005 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 "IPCThreadState"
18
19#include <binder/IPCThreadState.h>
20
21#include <binder/Binder.h>
22#include <binder/BpBinder.h>
23#include <binder/TextOutput.h>
24
25#include <cutils/sched_policy.h>
26#include <utils/Log.h>
27#include <utils/SystemClock.h>
28#include <utils/threads.h>
29
30#include <private/binder/binder_module.h>
31#include <private/binder/Static.h>
32
33#include <errno.h>
34#include <inttypes.h>
35#include <pthread.h>
36#include <sched.h>
37#include <signal.h>
38#include <stdio.h>
39#include <sys/ioctl.h>
40#include <sys/resource.h>
41#include <unistd.h>
42
43#if LOG_NDEBUG
44
45#define IF_LOG_TRANSACTIONS() if (false)
46#define IF_LOG_COMMANDS() if (false)
47#define LOG_REMOTEREFS(...)
48#define IF_LOG_REMOTEREFS() if (false)
49
50#define LOG_THREADPOOL(...)
51#define LOG_ONEWAY(...)
52
53#else
54
55#define IF_LOG_TRANSACTIONS() IF_ALOG(LOG_VERBOSE, "transact")
56#define IF_LOG_COMMANDS() IF_ALOG(LOG_VERBOSE, "ipc")
57#define LOG_REMOTEREFS(...) ALOG(LOG_DEBUG, "remoterefs", __VA_ARGS__)
58#define IF_LOG_REMOTEREFS() IF_ALOG(LOG_DEBUG, "remoterefs")
59#define LOG_THREADPOOL(...) ALOG(LOG_DEBUG, "threadpool", __VA_ARGS__)
60#define LOG_ONEWAY(...) ALOG(LOG_DEBUG, "ipc", __VA_ARGS__)
61
62#endif
63
64// ---------------------------------------------------------------------------
65
66namespace android {
67
68// Static const and functions will be optimized out if not used,
69// when LOG_NDEBUG and references in IF_LOG_COMMANDS() are optimized out.
70static const char *kReturnStrings[] = {
71    "BR_ERROR",
72    "BR_OK",
73    "BR_TRANSACTION",
74    "BR_REPLY",
75    "BR_ACQUIRE_RESULT",
76    "BR_DEAD_REPLY",
77    "BR_TRANSACTION_COMPLETE",
78    "BR_INCREFS",
79    "BR_ACQUIRE",
80    "BR_RELEASE",
81    "BR_DECREFS",
82    "BR_ATTEMPT_ACQUIRE",
83    "BR_NOOP",
84    "BR_SPAWN_LOOPER",
85    "BR_FINISHED",
86    "BR_DEAD_BINDER",
87    "BR_CLEAR_DEATH_NOTIFICATION_DONE",
88    "BR_FAILED_REPLY"
89};
90
91static const char *kCommandStrings[] = {
92    "BC_TRANSACTION",
93    "BC_REPLY",
94    "BC_ACQUIRE_RESULT",
95    "BC_FREE_BUFFER",
96    "BC_INCREFS",
97    "BC_ACQUIRE",
98    "BC_RELEASE",
99    "BC_DECREFS",
100    "BC_INCREFS_DONE",
101    "BC_ACQUIRE_DONE",
102    "BC_ATTEMPT_ACQUIRE",
103    "BC_REGISTER_LOOPER",
104    "BC_ENTER_LOOPER",
105    "BC_EXIT_LOOPER",
106    "BC_REQUEST_DEATH_NOTIFICATION",
107    "BC_CLEAR_DEATH_NOTIFICATION",
108    "BC_DEAD_BINDER_DONE"
109};
110
111static const char* getReturnString(uint32_t cmd)
112{
113    size_t idx = cmd & 0xff;
114    if (idx < sizeof(kReturnStrings) / sizeof(kReturnStrings[0]))
115        return kReturnStrings[idx];
116    else
117        return "unknown";
118}
119
120static const void* printBinderTransactionData(TextOutput& out, const void* data)
121{
122    const binder_transaction_data* btd =
123        (const binder_transaction_data*)data;
124    if (btd->target.handle < 1024) {
125        /* want to print descriptors in decimal; guess based on value */
126        out << "target.desc=" << btd->target.handle;
127    } else {
128        out << "target.ptr=" << btd->target.ptr;
129    }
130    out << " (cookie " << btd->cookie << ")" << endl
131        << "code=" << TypeCode(btd->code) << ", flags=" << (void*)(long)btd->flags << endl
132        << "data=" << btd->data.ptr.buffer << " (" << (void*)btd->data_size
133        << " bytes)" << endl
134        << "offsets=" << btd->data.ptr.offsets << " (" << (void*)btd->offsets_size
135        << " bytes)";
136    return btd+1;
137}
138
139static const void* printReturnCommand(TextOutput& out, const void* _cmd)
140{
141    static const size_t N = sizeof(kReturnStrings)/sizeof(kReturnStrings[0]);
142    const int32_t* cmd = (const int32_t*)_cmd;
143    uint32_t code = (uint32_t)*cmd++;
144    size_t cmdIndex = code & 0xff;
145    if (code == BR_ERROR) {
146        out << "BR_ERROR: " << (void*)(long)(*cmd++) << endl;
147        return cmd;
148    } else if (cmdIndex >= N) {
149        out << "Unknown reply: " << code << endl;
150        return cmd;
151    }
152    out << kReturnStrings[cmdIndex];
153
154    switch (code) {
155        case BR_TRANSACTION:
156        case BR_REPLY: {
157            out << ": " << indent;
158            cmd = (const int32_t *)printBinderTransactionData(out, cmd);
159            out << dedent;
160        } break;
161
162        case BR_ACQUIRE_RESULT: {
163            const int32_t res = *cmd++;
164            out << ": " << res << (res ? " (SUCCESS)" : " (FAILURE)");
165        } break;
166
167        case BR_INCREFS:
168        case BR_ACQUIRE:
169        case BR_RELEASE:
170        case BR_DECREFS: {
171            const int32_t b = *cmd++;
172            const int32_t c = *cmd++;
173            out << ": target=" << (void*)(long)b << " (cookie " << (void*)(long)c << ")";
174        } break;
175
176        case BR_ATTEMPT_ACQUIRE: {
177            const int32_t p = *cmd++;
178            const int32_t b = *cmd++;
179            const int32_t c = *cmd++;
180            out << ": target=" << (void*)(long)b << " (cookie " << (void*)(long)c
181                << "), pri=" << p;
182        } break;
183
184        case BR_DEAD_BINDER:
185        case BR_CLEAR_DEATH_NOTIFICATION_DONE: {
186            const int32_t c = *cmd++;
187            out << ": death cookie " << (void*)(long)c;
188        } break;
189
190        default:
191            // no details to show for: BR_OK, BR_DEAD_REPLY,
192            // BR_TRANSACTION_COMPLETE, BR_FINISHED
193            break;
194    }
195
196    out << endl;
197    return cmd;
198}
199
200static const void* printCommand(TextOutput& out, const void* _cmd)
201{
202    static const size_t N = sizeof(kCommandStrings)/sizeof(kCommandStrings[0]);
203    const int32_t* cmd = (const int32_t*)_cmd;
204    uint32_t code = (uint32_t)*cmd++;
205    size_t cmdIndex = code & 0xff;
206
207    if (cmdIndex >= N) {
208        out << "Unknown command: " << code << endl;
209        return cmd;
210    }
211    out << kCommandStrings[cmdIndex];
212
213    switch (code) {
214        case BC_TRANSACTION:
215        case BC_REPLY: {
216            out << ": " << indent;
217            cmd = (const int32_t *)printBinderTransactionData(out, cmd);
218            out << dedent;
219        } break;
220
221        case BC_ACQUIRE_RESULT: {
222            const int32_t res = *cmd++;
223            out << ": " << res << (res ? " (SUCCESS)" : " (FAILURE)");
224        } break;
225
226        case BC_FREE_BUFFER: {
227            const int32_t buf = *cmd++;
228            out << ": buffer=" << (void*)(long)buf;
229        } break;
230
231        case BC_INCREFS:
232        case BC_ACQUIRE:
233        case BC_RELEASE:
234        case BC_DECREFS: {
235            const int32_t d = *cmd++;
236            out << ": desc=" << d;
237        } break;
238
239        case BC_INCREFS_DONE:
240        case BC_ACQUIRE_DONE: {
241            const int32_t b = *cmd++;
242            const int32_t c = *cmd++;
243            out << ": target=" << (void*)(long)b << " (cookie " << (void*)(long)c << ")";
244        } break;
245
246        case BC_ATTEMPT_ACQUIRE: {
247            const int32_t p = *cmd++;
248            const int32_t d = *cmd++;
249            out << ": desc=" << d << ", pri=" << p;
250        } break;
251
252        case BC_REQUEST_DEATH_NOTIFICATION:
253        case BC_CLEAR_DEATH_NOTIFICATION: {
254            const int32_t h = *cmd++;
255            const int32_t c = *cmd++;
256            out << ": handle=" << h << " (death cookie " << (void*)(long)c << ")";
257        } break;
258
259        case BC_DEAD_BINDER_DONE: {
260            const int32_t c = *cmd++;
261            out << ": death cookie " << (void*)(long)c;
262        } break;
263
264        default:
265            // no details to show for: BC_REGISTER_LOOPER, BC_ENTER_LOOPER,
266            // BC_EXIT_LOOPER
267            break;
268    }
269
270    out << endl;
271    return cmd;
272}
273
274static pthread_mutex_t gTLSMutex = PTHREAD_MUTEX_INITIALIZER;
275static bool gHaveTLS = false;
276static pthread_key_t gTLS = 0;
277static bool gShutdown = false;
278static bool gDisableBackgroundScheduling = false;
279
280IPCThreadState* IPCThreadState::self()
281{
282    if (gHaveTLS) {
283restart:
284        const pthread_key_t k = gTLS;
285        IPCThreadState* st = (IPCThreadState*)pthread_getspecific(k);
286        if (st) return st;
287        return new IPCThreadState;
288    }
289
290    if (gShutdown) {
291        ALOGW("Calling IPCThreadState::self() during shutdown is dangerous, expect a crash.\n");
292        return NULL;
293    }
294
295    pthread_mutex_lock(&gTLSMutex);
296    if (!gHaveTLS) {
297        int key_create_value = pthread_key_create(&gTLS, threadDestructor);
298        if (key_create_value != 0) {
299            pthread_mutex_unlock(&gTLSMutex);
300            ALOGW("IPCThreadState::self() unable to create TLS key, expect a crash: %s\n",
301                    strerror(key_create_value));
302            return NULL;
303        }
304        gHaveTLS = true;
305    }
306    pthread_mutex_unlock(&gTLSMutex);
307    goto restart;
308}
309
310IPCThreadState* IPCThreadState::selfOrNull()
311{
312    if (gHaveTLS) {
313        const pthread_key_t k = gTLS;
314        IPCThreadState* st = (IPCThreadState*)pthread_getspecific(k);
315        return st;
316    }
317    return NULL;
318}
319
320void IPCThreadState::shutdown()
321{
322    gShutdown = true;
323
324    if (gHaveTLS) {
325        // XXX Need to wait for all thread pool threads to exit!
326        IPCThreadState* st = (IPCThreadState*)pthread_getspecific(gTLS);
327        if (st) {
328            delete st;
329            pthread_setspecific(gTLS, NULL);
330        }
331        pthread_key_delete(gTLS);
332        gHaveTLS = false;
333    }
334}
335
336void IPCThreadState::disableBackgroundScheduling(bool disable)
337{
338    gDisableBackgroundScheduling = disable;
339}
340
341bool IPCThreadState::backgroundSchedulingDisabled()
342{
343    return gDisableBackgroundScheduling;
344}
345
346sp<ProcessState> IPCThreadState::process()
347{
348    return mProcess;
349}
350
351status_t IPCThreadState::clearLastError()
352{
353    const status_t err = mLastError;
354    mLastError = NO_ERROR;
355    return err;
356}
357
358pid_t IPCThreadState::getCallingPid() const
359{
360    return mCallingPid;
361}
362
363uid_t IPCThreadState::getCallingUid() const
364{
365    return mCallingUid;
366}
367
368int64_t IPCThreadState::clearCallingIdentity()
369{
370    int64_t token = ((int64_t)mCallingUid<<32) | mCallingPid;
371    clearCaller();
372    return token;
373}
374
375void IPCThreadState::setStrictModePolicy(int32_t policy)
376{
377    mStrictModePolicy = policy;
378}
379
380int32_t IPCThreadState::getStrictModePolicy() const
381{
382    return mStrictModePolicy;
383}
384
385void IPCThreadState::setLastTransactionBinderFlags(int32_t flags)
386{
387    mLastTransactionBinderFlags = flags;
388}
389
390int32_t IPCThreadState::getLastTransactionBinderFlags() const
391{
392    return mLastTransactionBinderFlags;
393}
394
395void IPCThreadState::restoreCallingIdentity(int64_t token)
396{
397    mCallingUid = (int)(token>>32);
398    mCallingPid = (int)token;
399}
400
401void IPCThreadState::clearCaller()
402{
403    mCallingPid = getpid();
404    mCallingUid = getuid();
405}
406
407void IPCThreadState::flushCommands()
408{
409    if (mProcess->mDriverFD <= 0)
410        return;
411    talkWithDriver(false);
412}
413
414void IPCThreadState::blockUntilThreadAvailable()
415{
416    pthread_mutex_lock(&mProcess->mThreadCountLock);
417    while (mProcess->mExecutingThreadsCount >= mProcess->mMaxThreads) {
418        ALOGW("Waiting for thread to be free. mExecutingThreadsCount=%lu mMaxThreads=%lu\n",
419                static_cast<unsigned long>(mProcess->mExecutingThreadsCount),
420                static_cast<unsigned long>(mProcess->mMaxThreads));
421        pthread_cond_wait(&mProcess->mThreadCountDecrement, &mProcess->mThreadCountLock);
422    }
423    pthread_mutex_unlock(&mProcess->mThreadCountLock);
424}
425
426status_t IPCThreadState::getAndExecuteCommand()
427{
428    status_t result;
429    int32_t cmd;
430
431    result = talkWithDriver();
432    if (result >= NO_ERROR) {
433        size_t IN = mIn.dataAvail();
434        if (IN < sizeof(int32_t)) return result;
435        cmd = mIn.readInt32();
436        IF_LOG_COMMANDS() {
437            alog << "Processing top-level Command: "
438                 << getReturnString(cmd) << endl;
439        }
440
441        pthread_mutex_lock(&mProcess->mThreadCountLock);
442        mProcess->mExecutingThreadsCount++;
443        if (mProcess->mExecutingThreadsCount >= mProcess->mMaxThreads &&
444                mProcess->mStarvationStartTimeMs == 0) {
445            mProcess->mStarvationStartTimeMs = uptimeMillis();
446        }
447        pthread_mutex_unlock(&mProcess->mThreadCountLock);
448
449        result = executeCommand(cmd);
450
451        pthread_mutex_lock(&mProcess->mThreadCountLock);
452        mProcess->mExecutingThreadsCount--;
453        if (mProcess->mExecutingThreadsCount < mProcess->mMaxThreads &&
454                mProcess->mStarvationStartTimeMs != 0) {
455            int64_t starvationTimeMs = uptimeMillis() - mProcess->mStarvationStartTimeMs;
456            if (starvationTimeMs > 100) {
457                ALOGE("binder thread pool (%zu threads) starved for %" PRId64 " ms",
458                      mProcess->mMaxThreads, starvationTimeMs);
459            }
460            mProcess->mStarvationStartTimeMs = 0;
461        }
462        pthread_cond_broadcast(&mProcess->mThreadCountDecrement);
463        pthread_mutex_unlock(&mProcess->mThreadCountLock);
464    }
465
466    return result;
467}
468
469// When we've cleared the incoming command queue, process any pending derefs
470void IPCThreadState::processPendingDerefs()
471{
472    if (mIn.dataPosition() >= mIn.dataSize()) {
473        size_t numPending = mPendingWeakDerefs.size();
474        if (numPending > 0) {
475            for (size_t i = 0; i < numPending; i++) {
476                RefBase::weakref_type* refs = mPendingWeakDerefs[i];
477                refs->decWeak(mProcess.get());
478            }
479            mPendingWeakDerefs.clear();
480        }
481
482        numPending = mPendingStrongDerefs.size();
483        if (numPending > 0) {
484            for (size_t i = 0; i < numPending; i++) {
485                BBinder* obj = mPendingStrongDerefs[i];
486                obj->decStrong(mProcess.get());
487            }
488            mPendingStrongDerefs.clear();
489        }
490    }
491}
492
493void IPCThreadState::joinThreadPool(bool isMain)
494{
495    LOG_THREADPOOL("**** THREAD %p (PID %d) IS JOINING THE THREAD POOL\n", (void*)pthread_self(), getpid());
496
497    mOut.writeInt32(isMain ? BC_ENTER_LOOPER : BC_REGISTER_LOOPER);
498
499    status_t result;
500    do {
501        processPendingDerefs();
502        // now get the next command to be processed, waiting if necessary
503        result = getAndExecuteCommand();
504
505        if (result < NO_ERROR && result != TIMED_OUT && result != -ECONNREFUSED && result != -EBADF) {
506            ALOGE("getAndExecuteCommand(fd=%d) returned unexpected error %d, aborting",
507                  mProcess->mDriverFD, result);
508            abort();
509        }
510
511        // Let this thread exit the thread pool if it is no longer
512        // needed and it is not the main process thread.
513        if(result == TIMED_OUT && !isMain) {
514            break;
515        }
516    } while (result != -ECONNREFUSED && result != -EBADF);
517
518    LOG_THREADPOOL("**** THREAD %p (PID %d) IS LEAVING THE THREAD POOL err=%d\n",
519        (void*)pthread_self(), getpid(), result);
520
521    mOut.writeInt32(BC_EXIT_LOOPER);
522    talkWithDriver(false);
523}
524
525int IPCThreadState::setupPolling(int* fd)
526{
527    if (mProcess->mDriverFD <= 0) {
528        return -EBADF;
529    }
530
531    mOut.writeInt32(BC_ENTER_LOOPER);
532    *fd = mProcess->mDriverFD;
533    return 0;
534}
535
536status_t IPCThreadState::handlePolledCommands()
537{
538    status_t result;
539
540    do {
541        result = getAndExecuteCommand();
542    } while (mIn.dataPosition() < mIn.dataSize());
543
544    processPendingDerefs();
545    flushCommands();
546    return result;
547}
548
549void IPCThreadState::stopProcess(bool /*immediate*/)
550{
551    //ALOGI("**** STOPPING PROCESS");
552    flushCommands();
553    int fd = mProcess->mDriverFD;
554    mProcess->mDriverFD = -1;
555    close(fd);
556    //kill(getpid(), SIGKILL);
557}
558
559status_t IPCThreadState::transact(int32_t handle,
560                                  uint32_t code, const Parcel& data,
561                                  Parcel* reply, uint32_t flags)
562{
563    status_t err = data.errorCheck();
564
565    flags |= TF_ACCEPT_FDS;
566
567    IF_LOG_TRANSACTIONS() {
568        TextOutput::Bundle _b(alog);
569        alog << "BC_TRANSACTION thr " << (void*)pthread_self() << " / hand "
570            << handle << " / code " << TypeCode(code) << ": "
571            << indent << data << dedent << endl;
572    }
573
574    if (err == NO_ERROR) {
575        LOG_ONEWAY(">>>> SEND from pid %d uid %d %s", getpid(), getuid(),
576            (flags & TF_ONE_WAY) == 0 ? "READ REPLY" : "ONE WAY");
577        err = writeTransactionData(BC_TRANSACTION, flags, handle, code, data, NULL);
578    }
579
580    if (err != NO_ERROR) {
581        if (reply) reply->setError(err);
582        return (mLastError = err);
583    }
584
585    if ((flags & TF_ONE_WAY) == 0) {
586        #if 0
587        if (code == 4) { // relayout
588            ALOGI(">>>>>> CALLING transaction 4");
589        } else {
590            ALOGI(">>>>>> CALLING transaction %d", code);
591        }
592        #endif
593        if (reply) {
594            err = waitForResponse(reply);
595        } else {
596            Parcel fakeReply;
597            err = waitForResponse(&fakeReply);
598        }
599        #if 0
600        if (code == 4) { // relayout
601            ALOGI("<<<<<< RETURNING transaction 4");
602        } else {
603            ALOGI("<<<<<< RETURNING transaction %d", code);
604        }
605        #endif
606
607        IF_LOG_TRANSACTIONS() {
608            TextOutput::Bundle _b(alog);
609            alog << "BR_REPLY thr " << (void*)pthread_self() << " / hand "
610                << handle << ": ";
611            if (reply) alog << indent << *reply << dedent << endl;
612            else alog << "(none requested)" << endl;
613        }
614    } else {
615        err = waitForResponse(NULL, NULL);
616    }
617
618    return err;
619}
620
621void IPCThreadState::incStrongHandle(int32_t handle)
622{
623    LOG_REMOTEREFS("IPCThreadState::incStrongHandle(%d)\n", handle);
624    mOut.writeInt32(BC_ACQUIRE);
625    mOut.writeInt32(handle);
626}
627
628void IPCThreadState::decStrongHandle(int32_t handle)
629{
630    LOG_REMOTEREFS("IPCThreadState::decStrongHandle(%d)\n", handle);
631    mOut.writeInt32(BC_RELEASE);
632    mOut.writeInt32(handle);
633}
634
635void IPCThreadState::incWeakHandle(int32_t handle)
636{
637    LOG_REMOTEREFS("IPCThreadState::incWeakHandle(%d)\n", handle);
638    mOut.writeInt32(BC_INCREFS);
639    mOut.writeInt32(handle);
640}
641
642void IPCThreadState::decWeakHandle(int32_t handle)
643{
644    LOG_REMOTEREFS("IPCThreadState::decWeakHandle(%d)\n", handle);
645    mOut.writeInt32(BC_DECREFS);
646    mOut.writeInt32(handle);
647}
648
649status_t IPCThreadState::attemptIncStrongHandle(int32_t handle)
650{
651#if HAS_BC_ATTEMPT_ACQUIRE
652    LOG_REMOTEREFS("IPCThreadState::attemptIncStrongHandle(%d)\n", handle);
653    mOut.writeInt32(BC_ATTEMPT_ACQUIRE);
654    mOut.writeInt32(0); // xxx was thread priority
655    mOut.writeInt32(handle);
656    status_t result = UNKNOWN_ERROR;
657
658    waitForResponse(NULL, &result);
659
660#if LOG_REFCOUNTS
661    ALOGV("IPCThreadState::attemptIncStrongHandle(%ld) = %s\n",
662        handle, result == NO_ERROR ? "SUCCESS" : "FAILURE");
663#endif
664
665    return result;
666#else
667    (void)handle;
668    ALOGE("%s(%d): Not supported\n", __func__, handle);
669    return INVALID_OPERATION;
670#endif
671}
672
673void IPCThreadState::expungeHandle(int32_t handle, IBinder* binder)
674{
675#if LOG_REFCOUNTS
676    ALOGV("IPCThreadState::expungeHandle(%ld)\n", handle);
677#endif
678    self()->mProcess->expungeHandle(handle, binder);
679}
680
681status_t IPCThreadState::requestDeathNotification(int32_t handle, BpBinder* proxy)
682{
683    mOut.writeInt32(BC_REQUEST_DEATH_NOTIFICATION);
684    mOut.writeInt32((int32_t)handle);
685    mOut.writePointer((uintptr_t)proxy);
686    return NO_ERROR;
687}
688
689status_t IPCThreadState::clearDeathNotification(int32_t handle, BpBinder* proxy)
690{
691    mOut.writeInt32(BC_CLEAR_DEATH_NOTIFICATION);
692    mOut.writeInt32((int32_t)handle);
693    mOut.writePointer((uintptr_t)proxy);
694    return NO_ERROR;
695}
696
697IPCThreadState::IPCThreadState()
698    : mProcess(ProcessState::self()),
699      mStrictModePolicy(0),
700      mLastTransactionBinderFlags(0)
701{
702    pthread_setspecific(gTLS, this);
703    clearCaller();
704    mIn.setDataCapacity(256);
705    mOut.setDataCapacity(256);
706}
707
708IPCThreadState::~IPCThreadState()
709{
710}
711
712status_t IPCThreadState::sendReply(const Parcel& reply, uint32_t flags)
713{
714    status_t err;
715    status_t statusBuffer;
716    err = writeTransactionData(BC_REPLY, flags, -1, 0, reply, &statusBuffer);
717    if (err < NO_ERROR) return err;
718
719    return waitForResponse(NULL, NULL);
720}
721
722status_t IPCThreadState::waitForResponse(Parcel *reply, status_t *acquireResult)
723{
724    uint32_t cmd;
725    int32_t err;
726
727    while (1) {
728        if ((err=talkWithDriver()) < NO_ERROR) break;
729        err = mIn.errorCheck();
730        if (err < NO_ERROR) break;
731        if (mIn.dataAvail() == 0) continue;
732
733        cmd = (uint32_t)mIn.readInt32();
734
735        IF_LOG_COMMANDS() {
736            alog << "Processing waitForResponse Command: "
737                << getReturnString(cmd) << endl;
738        }
739
740        switch (cmd) {
741        case BR_TRANSACTION_COMPLETE:
742            if (!reply && !acquireResult) goto finish;
743            break;
744
745        case BR_DEAD_REPLY:
746            err = DEAD_OBJECT;
747            goto finish;
748
749        case BR_FAILED_REPLY:
750            err = FAILED_TRANSACTION;
751            goto finish;
752
753        case BR_ACQUIRE_RESULT:
754            {
755                ALOG_ASSERT(acquireResult != NULL, "Unexpected brACQUIRE_RESULT");
756                const int32_t result = mIn.readInt32();
757                if (!acquireResult) continue;
758                *acquireResult = result ? NO_ERROR : INVALID_OPERATION;
759            }
760            goto finish;
761
762        case BR_REPLY:
763            {
764                binder_transaction_data tr;
765                err = mIn.read(&tr, sizeof(tr));
766                ALOG_ASSERT(err == NO_ERROR, "Not enough command data for brREPLY");
767                if (err != NO_ERROR) goto finish;
768
769                if (reply) {
770                    if ((tr.flags & TF_STATUS_CODE) == 0) {
771                        reply->ipcSetDataReference(
772                            reinterpret_cast<const uint8_t*>(tr.data.ptr.buffer),
773                            tr.data_size,
774                            reinterpret_cast<const binder_size_t*>(tr.data.ptr.offsets),
775                            tr.offsets_size/sizeof(binder_size_t),
776                            freeBuffer, this);
777                    } else {
778                        err = *reinterpret_cast<const status_t*>(tr.data.ptr.buffer);
779                        freeBuffer(NULL,
780                            reinterpret_cast<const uint8_t*>(tr.data.ptr.buffer),
781                            tr.data_size,
782                            reinterpret_cast<const binder_size_t*>(tr.data.ptr.offsets),
783                            tr.offsets_size/sizeof(binder_size_t), this);
784                    }
785                } else {
786                    freeBuffer(NULL,
787                        reinterpret_cast<const uint8_t*>(tr.data.ptr.buffer),
788                        tr.data_size,
789                        reinterpret_cast<const binder_size_t*>(tr.data.ptr.offsets),
790                        tr.offsets_size/sizeof(binder_size_t), this);
791                    continue;
792                }
793            }
794            goto finish;
795
796        default:
797            err = executeCommand(cmd);
798            if (err != NO_ERROR) goto finish;
799            break;
800        }
801    }
802
803finish:
804    if (err != NO_ERROR) {
805        if (acquireResult) *acquireResult = err;
806        if (reply) reply->setError(err);
807        mLastError = err;
808    }
809
810    return err;
811}
812
813status_t IPCThreadState::talkWithDriver(bool doReceive)
814{
815    if (mProcess->mDriverFD <= 0) {
816        return -EBADF;
817    }
818
819    binder_write_read bwr;
820
821    // Is the read buffer empty?
822    const bool needRead = mIn.dataPosition() >= mIn.dataSize();
823
824    // We don't want to write anything if we are still reading
825    // from data left in the input buffer and the caller
826    // has requested to read the next data.
827    const size_t outAvail = (!doReceive || needRead) ? mOut.dataSize() : 0;
828
829    bwr.write_size = outAvail;
830    bwr.write_buffer = (uintptr_t)mOut.data();
831
832    // This is what we'll read.
833    if (doReceive && needRead) {
834        bwr.read_size = mIn.dataCapacity();
835        bwr.read_buffer = (uintptr_t)mIn.data();
836    } else {
837        bwr.read_size = 0;
838        bwr.read_buffer = 0;
839    }
840
841    IF_LOG_COMMANDS() {
842        TextOutput::Bundle _b(alog);
843        if (outAvail != 0) {
844            alog << "Sending commands to driver: " << indent;
845            const void* cmds = (const void*)bwr.write_buffer;
846            const void* end = ((const uint8_t*)cmds)+bwr.write_size;
847            alog << HexDump(cmds, bwr.write_size) << endl;
848            while (cmds < end) cmds = printCommand(alog, cmds);
849            alog << dedent;
850        }
851        alog << "Size of receive buffer: " << bwr.read_size
852            << ", needRead: " << needRead << ", doReceive: " << doReceive << endl;
853    }
854
855    // Return immediately if there is nothing to do.
856    if ((bwr.write_size == 0) && (bwr.read_size == 0)) return NO_ERROR;
857
858    bwr.write_consumed = 0;
859    bwr.read_consumed = 0;
860    status_t err;
861    do {
862        IF_LOG_COMMANDS() {
863            alog << "About to read/write, write size = " << mOut.dataSize() << endl;
864        }
865#if defined(__ANDROID__)
866        if (ioctl(mProcess->mDriverFD, BINDER_WRITE_READ, &bwr) >= 0)
867            err = NO_ERROR;
868        else
869            err = -errno;
870#else
871        err = INVALID_OPERATION;
872#endif
873        if (mProcess->mDriverFD <= 0) {
874            err = -EBADF;
875        }
876        IF_LOG_COMMANDS() {
877            alog << "Finished read/write, write size = " << mOut.dataSize() << endl;
878        }
879    } while (err == -EINTR);
880
881    IF_LOG_COMMANDS() {
882        alog << "Our err: " << (void*)(intptr_t)err << ", write consumed: "
883            << bwr.write_consumed << " (of " << mOut.dataSize()
884                        << "), read consumed: " << bwr.read_consumed << endl;
885    }
886
887    if (err >= NO_ERROR) {
888        if (bwr.write_consumed > 0) {
889            if (bwr.write_consumed < mOut.dataSize())
890                mOut.remove(0, bwr.write_consumed);
891            else
892                mOut.setDataSize(0);
893        }
894        if (bwr.read_consumed > 0) {
895            mIn.setDataSize(bwr.read_consumed);
896            mIn.setDataPosition(0);
897        }
898        IF_LOG_COMMANDS() {
899            TextOutput::Bundle _b(alog);
900            alog << "Remaining data size: " << mOut.dataSize() << endl;
901            alog << "Received commands from driver: " << indent;
902            const void* cmds = mIn.data();
903            const void* end = mIn.data() + mIn.dataSize();
904            alog << HexDump(cmds, mIn.dataSize()) << endl;
905            while (cmds < end) cmds = printReturnCommand(alog, cmds);
906            alog << dedent;
907        }
908        return NO_ERROR;
909    }
910
911    return err;
912}
913
914status_t IPCThreadState::writeTransactionData(int32_t cmd, uint32_t binderFlags,
915    int32_t handle, uint32_t code, const Parcel& data, status_t* statusBuffer)
916{
917    binder_transaction_data tr;
918
919    tr.target.ptr = 0; /* Don't pass uninitialized stack data to a remote process */
920    tr.target.handle = handle;
921    tr.code = code;
922    tr.flags = binderFlags;
923    tr.cookie = 0;
924    tr.sender_pid = 0;
925    tr.sender_euid = 0;
926
927    const status_t err = data.errorCheck();
928    if (err == NO_ERROR) {
929        tr.data_size = data.ipcDataSize();
930        tr.data.ptr.buffer = data.ipcData();
931        tr.offsets_size = data.ipcObjectsCount()*sizeof(binder_size_t);
932        tr.data.ptr.offsets = data.ipcObjects();
933    } else if (statusBuffer) {
934        tr.flags |= TF_STATUS_CODE;
935        *statusBuffer = err;
936        tr.data_size = sizeof(status_t);
937        tr.data.ptr.buffer = reinterpret_cast<uintptr_t>(statusBuffer);
938        tr.offsets_size = 0;
939        tr.data.ptr.offsets = 0;
940    } else {
941        return (mLastError = err);
942    }
943
944    mOut.writeInt32(cmd);
945    mOut.write(&tr, sizeof(tr));
946
947    return NO_ERROR;
948}
949
950sp<BBinder> the_context_object;
951
952void setTheContextObject(sp<BBinder> obj)
953{
954    the_context_object = obj;
955}
956
957status_t IPCThreadState::executeCommand(int32_t cmd)
958{
959    BBinder* obj;
960    RefBase::weakref_type* refs;
961    status_t result = NO_ERROR;
962
963    switch ((uint32_t)cmd) {
964    case BR_ERROR:
965        result = mIn.readInt32();
966        break;
967
968    case BR_OK:
969        break;
970
971    case BR_ACQUIRE:
972        refs = (RefBase::weakref_type*)mIn.readPointer();
973        obj = (BBinder*)mIn.readPointer();
974        ALOG_ASSERT(refs->refBase() == obj,
975                   "BR_ACQUIRE: object %p does not match cookie %p (expected %p)",
976                   refs, obj, refs->refBase());
977        obj->incStrong(mProcess.get());
978        IF_LOG_REMOTEREFS() {
979            LOG_REMOTEREFS("BR_ACQUIRE from driver on %p", obj);
980            obj->printRefs();
981        }
982        mOut.writeInt32(BC_ACQUIRE_DONE);
983        mOut.writePointer((uintptr_t)refs);
984        mOut.writePointer((uintptr_t)obj);
985        break;
986
987    case BR_RELEASE:
988        refs = (RefBase::weakref_type*)mIn.readPointer();
989        obj = (BBinder*)mIn.readPointer();
990        ALOG_ASSERT(refs->refBase() == obj,
991                   "BR_RELEASE: object %p does not match cookie %p (expected %p)",
992                   refs, obj, refs->refBase());
993        IF_LOG_REMOTEREFS() {
994            LOG_REMOTEREFS("BR_RELEASE from driver on %p", obj);
995            obj->printRefs();
996        }
997        mPendingStrongDerefs.push(obj);
998        break;
999
1000    case BR_INCREFS:
1001        refs = (RefBase::weakref_type*)mIn.readPointer();
1002        obj = (BBinder*)mIn.readPointer();
1003        refs->incWeak(mProcess.get());
1004        mOut.writeInt32(BC_INCREFS_DONE);
1005        mOut.writePointer((uintptr_t)refs);
1006        mOut.writePointer((uintptr_t)obj);
1007        break;
1008
1009    case BR_DECREFS:
1010        refs = (RefBase::weakref_type*)mIn.readPointer();
1011        obj = (BBinder*)mIn.readPointer();
1012        // NOTE: This assertion is not valid, because the object may no
1013        // longer exist (thus the (BBinder*)cast above resulting in a different
1014        // memory address).
1015        //ALOG_ASSERT(refs->refBase() == obj,
1016        //           "BR_DECREFS: object %p does not match cookie %p (expected %p)",
1017        //           refs, obj, refs->refBase());
1018        mPendingWeakDerefs.push(refs);
1019        break;
1020
1021    case BR_ATTEMPT_ACQUIRE:
1022        refs = (RefBase::weakref_type*)mIn.readPointer();
1023        obj = (BBinder*)mIn.readPointer();
1024
1025        {
1026            const bool success = refs->attemptIncStrong(mProcess.get());
1027            ALOG_ASSERT(success && refs->refBase() == obj,
1028                       "BR_ATTEMPT_ACQUIRE: object %p does not match cookie %p (expected %p)",
1029                       refs, obj, refs->refBase());
1030
1031            mOut.writeInt32(BC_ACQUIRE_RESULT);
1032            mOut.writeInt32((int32_t)success);
1033        }
1034        break;
1035
1036    case BR_TRANSACTION:
1037        {
1038            binder_transaction_data tr;
1039            result = mIn.read(&tr, sizeof(tr));
1040            ALOG_ASSERT(result == NO_ERROR,
1041                "Not enough command data for brTRANSACTION");
1042            if (result != NO_ERROR) break;
1043
1044            Parcel buffer;
1045            buffer.ipcSetDataReference(
1046                reinterpret_cast<const uint8_t*>(tr.data.ptr.buffer),
1047                tr.data_size,
1048                reinterpret_cast<const binder_size_t*>(tr.data.ptr.offsets),
1049                tr.offsets_size/sizeof(binder_size_t), freeBuffer, this);
1050
1051            const pid_t origPid = mCallingPid;
1052            const uid_t origUid = mCallingUid;
1053            const int32_t origStrictModePolicy = mStrictModePolicy;
1054            const int32_t origTransactionBinderFlags = mLastTransactionBinderFlags;
1055
1056            mCallingPid = tr.sender_pid;
1057            mCallingUid = tr.sender_euid;
1058            mLastTransactionBinderFlags = tr.flags;
1059
1060            //ALOGI(">>>> TRANSACT from pid %d uid %d\n", mCallingPid, mCallingUid);
1061
1062            Parcel reply;
1063            status_t error;
1064            IF_LOG_TRANSACTIONS() {
1065                TextOutput::Bundle _b(alog);
1066                alog << "BR_TRANSACTION thr " << (void*)pthread_self()
1067                    << " / obj " << tr.target.ptr << " / code "
1068                    << TypeCode(tr.code) << ": " << indent << buffer
1069                    << dedent << endl
1070                    << "Data addr = "
1071                    << reinterpret_cast<const uint8_t*>(tr.data.ptr.buffer)
1072                    << ", offsets addr="
1073                    << reinterpret_cast<const size_t*>(tr.data.ptr.offsets) << endl;
1074            }
1075            if (tr.target.ptr) {
1076                // We only have a weak reference on the target object, so we must first try to
1077                // safely acquire a strong reference before doing anything else with it.
1078                if (reinterpret_cast<RefBase::weakref_type*>(
1079                        tr.target.ptr)->attemptIncStrong(this)) {
1080                    error = reinterpret_cast<BBinder*>(tr.cookie)->transact(tr.code, buffer,
1081                            &reply, tr.flags);
1082                    reinterpret_cast<BBinder*>(tr.cookie)->decStrong(this);
1083                } else {
1084                    error = UNKNOWN_TRANSACTION;
1085                }
1086
1087            } else {
1088                error = the_context_object->transact(tr.code, buffer, &reply, tr.flags);
1089            }
1090
1091            //ALOGI("<<<< TRANSACT from pid %d restore pid %d uid %d\n",
1092            //     mCallingPid, origPid, origUid);
1093
1094            if ((tr.flags & TF_ONE_WAY) == 0) {
1095                LOG_ONEWAY("Sending reply to %d!", mCallingPid);
1096                if (error < NO_ERROR) reply.setError(error);
1097                sendReply(reply, 0);
1098            } else {
1099                LOG_ONEWAY("NOT sending reply to %d!", mCallingPid);
1100            }
1101
1102            mCallingPid = origPid;
1103            mCallingUid = origUid;
1104            mStrictModePolicy = origStrictModePolicy;
1105            mLastTransactionBinderFlags = origTransactionBinderFlags;
1106
1107            IF_LOG_TRANSACTIONS() {
1108                TextOutput::Bundle _b(alog);
1109                alog << "BC_REPLY thr " << (void*)pthread_self() << " / obj "
1110                    << tr.target.ptr << ": " << indent << reply << dedent << endl;
1111            }
1112
1113        }
1114        break;
1115
1116    case BR_DEAD_BINDER:
1117        {
1118            BpBinder *proxy = (BpBinder*)mIn.readPointer();
1119            proxy->sendObituary();
1120            mOut.writeInt32(BC_DEAD_BINDER_DONE);
1121            mOut.writePointer((uintptr_t)proxy);
1122        } break;
1123
1124    case BR_CLEAR_DEATH_NOTIFICATION_DONE:
1125        {
1126            BpBinder *proxy = (BpBinder*)mIn.readPointer();
1127            proxy->getWeakRefs()->decWeak(proxy);
1128        } break;
1129
1130    case BR_FINISHED:
1131        result = TIMED_OUT;
1132        break;
1133
1134    case BR_NOOP:
1135        break;
1136
1137    case BR_SPAWN_LOOPER:
1138        mProcess->spawnPooledThread(false);
1139        break;
1140
1141    default:
1142        ALOGE("*** BAD COMMAND %d received from Binder driver\n", cmd);
1143        result = UNKNOWN_ERROR;
1144        break;
1145    }
1146
1147    if (result != NO_ERROR) {
1148        mLastError = result;
1149    }
1150
1151    return result;
1152}
1153
1154void IPCThreadState::threadDestructor(void *st)
1155{
1156        IPCThreadState* const self = static_cast<IPCThreadState*>(st);
1157        if (self) {
1158                self->flushCommands();
1159#if defined(__ANDROID__)
1160        if (self->mProcess->mDriverFD > 0) {
1161            ioctl(self->mProcess->mDriverFD, BINDER_THREAD_EXIT, 0);
1162        }
1163#endif
1164                delete self;
1165        }
1166}
1167
1168
1169void IPCThreadState::freeBuffer(Parcel* parcel, const uint8_t* data,
1170                                size_t /*dataSize*/,
1171                                const binder_size_t* /*objects*/,
1172                                size_t /*objectsSize*/, void* /*cookie*/)
1173{
1174    //ALOGI("Freeing parcel %p", &parcel);
1175    IF_LOG_COMMANDS() {
1176        alog << "Writing BC_FREE_BUFFER for " << data << endl;
1177    }
1178    ALOG_ASSERT(data != NULL, "Called with NULL data");
1179    if (parcel != NULL) parcel->closeFileDescriptors();
1180    IPCThreadState* state = self();
1181    state->mOut.writeInt32(BC_FREE_BUFFER);
1182    state->mOut.writePointer((uintptr_t)data);
1183}
1184
1185}; // namespace android
1186