IPCThreadState.cpp revision c5b2c0bf8007562536b822eb060fc54a01f8e08b
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#include <binder/IPCThreadState.h>
18
19#include <binder/Binder.h>
20#include <binder/BpBinder.h>
21#include <utils/Debug.h>
22#include <utils/Log.h>
23#include <utils/TextOutput.h>
24#include <utils/threads.h>
25
26#include <private/binder/binder_module.h>
27#include <private/binder/Static.h>
28
29#include <sys/ioctl.h>
30#include <signal.h>
31#include <errno.h>
32#include <stdio.h>
33#include <unistd.h>
34
35#ifdef HAVE_PTHREADS
36#include <pthread.h>
37#include <sched.h>
38#include <sys/resource.h>
39#endif
40#ifdef HAVE_WIN32_THREADS
41#include <windows.h>
42#endif
43
44
45#if LOG_NDEBUG
46
47#define IF_LOG_TRANSACTIONS() if (false)
48#define IF_LOG_COMMANDS() if (false)
49#define LOG_REMOTEREFS(...)
50#define IF_LOG_REMOTEREFS() if (false)
51#define LOG_THREADPOOL(...)
52#define LOG_ONEWAY(...)
53
54#else
55
56#define IF_LOG_TRANSACTIONS() IF_LOG(LOG_VERBOSE, "transact")
57#define IF_LOG_COMMANDS() IF_LOG(LOG_VERBOSE, "ipc")
58#define LOG_REMOTEREFS(...) LOG(LOG_DEBUG, "remoterefs", __VA_ARGS__)
59#define IF_LOG_REMOTEREFS() IF_LOG(LOG_DEBUG, "remoterefs")
60#define LOG_THREADPOOL(...) LOG(LOG_DEBUG, "threadpool", __VA_ARGS__)
61#define LOG_ONEWAY(...) LOG(LOG_DEBUG, "ipc", __VA_ARGS__)
62
63#endif
64
65// ---------------------------------------------------------------------------
66
67namespace android {
68
69static const char* getReturnString(size_t idx);
70static const char* getCommandString(size_t idx);
71static const void* printReturnCommand(TextOutput& out, const void* _cmd);
72static const void* printCommand(TextOutput& out, const void* _cmd);
73
74// This will result in a missing symbol failure if the IF_LOG_COMMANDS()
75// conditionals don't get stripped...  but that is probably what we want.
76#if !LOG_NDEBUG
77static const char *kReturnStrings[] = {
78#if 1 /* TODO: error update strings */
79    "unknown",
80#else
81    "BR_OK",
82    "BR_TIMEOUT",
83    "BR_WAKEUP",
84    "BR_TRANSACTION",
85    "BR_REPLY",
86    "BR_ACQUIRE_RESULT",
87    "BR_DEAD_REPLY",
88    "BR_TRANSACTION_COMPLETE",
89    "BR_INCREFS",
90    "BR_ACQUIRE",
91    "BR_RELEASE",
92    "BR_DECREFS",
93    "BR_ATTEMPT_ACQUIRE",
94    "BR_EVENT_OCCURRED",
95    "BR_NOOP",
96    "BR_SPAWN_LOOPER",
97    "BR_FINISHED",
98    "BR_DEAD_BINDER",
99    "BR_CLEAR_DEATH_NOTIFICATION_DONE"
100#endif
101};
102
103static const char *kCommandStrings[] = {
104#if 1 /* TODO: error update strings */
105    "unknown",
106#else
107    "BC_NOOP",
108    "BC_TRANSACTION",
109    "BC_REPLY",
110    "BC_ACQUIRE_RESULT",
111    "BC_FREE_BUFFER",
112    "BC_TRANSACTION_COMPLETE",
113    "BC_INCREFS",
114    "BC_ACQUIRE",
115    "BC_RELEASE",
116    "BC_DECREFS",
117    "BC_INCREFS_DONE",
118    "BC_ACQUIRE_DONE",
119    "BC_ATTEMPT_ACQUIRE",
120    "BC_RETRIEVE_ROOT_OBJECT",
121    "BC_SET_THREAD_ENTRY",
122    "BC_REGISTER_LOOPER",
123    "BC_ENTER_LOOPER",
124    "BC_EXIT_LOOPER",
125    "BC_SYNC",
126    "BC_STOP_PROCESS",
127    "BC_STOP_SELF",
128    "BC_REQUEST_DEATH_NOTIFICATION",
129    "BC_CLEAR_DEATH_NOTIFICATION",
130    "BC_DEAD_BINDER_DONE"
131#endif
132};
133
134static const char* getReturnString(size_t idx)
135{
136    if (idx < sizeof(kReturnStrings) / sizeof(kReturnStrings[0]))
137        return kReturnStrings[idx];
138    else
139        return "unknown";
140}
141
142static const char* getCommandString(size_t idx)
143{
144    if (idx < sizeof(kCommandStrings) / sizeof(kCommandStrings[0]))
145        return kCommandStrings[idx];
146    else
147        return "unknown";
148}
149
150static const void* printBinderTransactionData(TextOutput& out, const void* data)
151{
152    const binder_transaction_data* btd =
153        (const binder_transaction_data*)data;
154    out << "target=" << btd->target.ptr << " (cookie " << btd->cookie << ")" << endl
155        << "code=" << TypeCode(btd->code) << ", flags=" << (void*)btd->flags << endl
156        << "data=" << btd->data.ptr.buffer << " (" << (void*)btd->data_size
157        << " bytes)" << endl
158        << "offsets=" << btd->data.ptr.offsets << " (" << (void*)btd->offsets_size
159        << " bytes)" << endl;
160    return btd+1;
161}
162
163static const void* printReturnCommand(TextOutput& out, const void* _cmd)
164{
165    static const int32_t N = sizeof(kReturnStrings)/sizeof(kReturnStrings[0]);
166
167    const int32_t* cmd = (const int32_t*)_cmd;
168    int32_t code = *cmd++;
169    if (code == BR_ERROR) {
170        out << "BR_ERROR: " << (void*)(*cmd++) << endl;
171        return cmd;
172    } else if (code < 0 || code >= N) {
173        out << "Unknown reply: " << code << endl;
174        return cmd;
175    }
176
177    out << kReturnStrings[code];
178    switch (code) {
179        case BR_TRANSACTION:
180        case BR_REPLY: {
181            out << ": " << indent;
182            cmd = (const int32_t *)printBinderTransactionData(out, cmd);
183            out << dedent;
184        } break;
185
186        case BR_ACQUIRE_RESULT: {
187            const int32_t res = *cmd++;
188            out << ": " << res << (res ? " (SUCCESS)" : " (FAILURE)");
189        } break;
190
191        case BR_INCREFS:
192        case BR_ACQUIRE:
193        case BR_RELEASE:
194        case BR_DECREFS: {
195            const int32_t b = *cmd++;
196            const int32_t c = *cmd++;
197            out << ": target=" << (void*)b << " (cookie " << (void*)c << ")";
198        } break;
199
200        case BR_ATTEMPT_ACQUIRE: {
201            const int32_t p = *cmd++;
202            const int32_t b = *cmd++;
203            const int32_t c = *cmd++;
204            out << ": target=" << (void*)b << " (cookie " << (void*)c
205                << "), pri=" << p;
206        } break;
207
208        case BR_DEAD_BINDER:
209        case BR_CLEAR_DEATH_NOTIFICATION_DONE: {
210            const int32_t c = *cmd++;
211            out << ": death cookie " << (void*)c;
212        } break;
213    }
214
215    out << endl;
216    return cmd;
217}
218
219static const void* printCommand(TextOutput& out, const void* _cmd)
220{
221    static const int32_t N = sizeof(kCommandStrings)/sizeof(kCommandStrings[0]);
222
223    const int32_t* cmd = (const int32_t*)_cmd;
224    int32_t code = *cmd++;
225    if (code < 0 || code >= N) {
226        out << "Unknown command: " << code << endl;
227        return cmd;
228    }
229
230    out << kCommandStrings[code];
231    switch (code) {
232        case BC_TRANSACTION:
233        case BC_REPLY: {
234            out << ": " << indent;
235            cmd = (const int32_t *)printBinderTransactionData(out, cmd);
236            out << dedent;
237        } break;
238
239        case BC_ACQUIRE_RESULT: {
240            const int32_t res = *cmd++;
241            out << ": " << res << (res ? " (SUCCESS)" : " (FAILURE)");
242        } break;
243
244        case BC_FREE_BUFFER: {
245            const int32_t buf = *cmd++;
246            out << ": buffer=" << (void*)buf;
247        } break;
248
249        case BC_INCREFS:
250        case BC_ACQUIRE:
251        case BC_RELEASE:
252        case BC_DECREFS: {
253            const int32_t d = *cmd++;
254            out << ": descriptor=" << (void*)d;
255        } break;
256
257        case BC_INCREFS_DONE:
258        case BC_ACQUIRE_DONE: {
259            const int32_t b = *cmd++;
260            const int32_t c = *cmd++;
261            out << ": target=" << (void*)b << " (cookie " << (void*)c << ")";
262        } break;
263
264        case BC_ATTEMPT_ACQUIRE: {
265            const int32_t p = *cmd++;
266            const int32_t d = *cmd++;
267            out << ": decriptor=" << (void*)d << ", pri=" << p;
268        } break;
269
270        case BC_REQUEST_DEATH_NOTIFICATION:
271        case BC_CLEAR_DEATH_NOTIFICATION: {
272            const int32_t h = *cmd++;
273            const int32_t c = *cmd++;
274            out << ": handle=" << h << " (death cookie " << (void*)c << ")";
275        } break;
276
277        case BC_DEAD_BINDER_DONE: {
278            const int32_t c = *cmd++;
279            out << ": death cookie " << (void*)c;
280        } break;
281    }
282
283    out << endl;
284    return cmd;
285}
286#endif
287
288static pthread_mutex_t gTLSMutex = PTHREAD_MUTEX_INITIALIZER;
289static bool gHaveTLS = false;
290static pthread_key_t gTLS = 0;
291static bool gShutdown = false;
292
293IPCThreadState* IPCThreadState::self()
294{
295    if (gHaveTLS) {
296restart:
297        const pthread_key_t k = gTLS;
298        IPCThreadState* st = (IPCThreadState*)pthread_getspecific(k);
299        if (st) return st;
300        return new IPCThreadState;
301    }
302
303    if (gShutdown) return NULL;
304
305    pthread_mutex_lock(&gTLSMutex);
306    if (!gHaveTLS) {
307        if (pthread_key_create(&gTLS, threadDestructor) != 0) {
308            pthread_mutex_unlock(&gTLSMutex);
309            return NULL;
310        }
311        gHaveTLS = true;
312    }
313    pthread_mutex_unlock(&gTLSMutex);
314    goto restart;
315}
316
317void IPCThreadState::shutdown()
318{
319    gShutdown = true;
320
321    if (gHaveTLS) {
322        // XXX Need to wait for all thread pool threads to exit!
323        IPCThreadState* st = (IPCThreadState*)pthread_getspecific(gTLS);
324        if (st) {
325            delete st;
326            pthread_setspecific(gTLS, NULL);
327        }
328        gHaveTLS = false;
329    }
330}
331
332sp<ProcessState> IPCThreadState::process()
333{
334    return mProcess;
335}
336
337status_t IPCThreadState::clearLastError()
338{
339    const status_t err = mLastError;
340    mLastError = NO_ERROR;
341    return err;
342}
343
344int IPCThreadState::getCallingPid()
345{
346    return mCallingPid;
347}
348
349int IPCThreadState::getCallingUid()
350{
351    return mCallingUid;
352}
353
354int64_t IPCThreadState::clearCallingIdentity()
355{
356    int64_t token = ((int64_t)mCallingUid<<32) | mCallingPid;
357    clearCaller();
358    return token;
359}
360
361void IPCThreadState::restoreCallingIdentity(int64_t token)
362{
363    mCallingUid = (int)(token>>32);
364    mCallingPid = (int)token;
365}
366
367void IPCThreadState::clearCaller()
368{
369    if (mProcess->supportsProcesses()) {
370        mCallingPid = getpid();
371        mCallingUid = getuid();
372    } else {
373        mCallingPid = -1;
374        mCallingUid = -1;
375    }
376}
377
378void IPCThreadState::flushCommands()
379{
380    if (mProcess->mDriverFD <= 0)
381        return;
382    talkWithDriver(false);
383}
384
385void IPCThreadState::joinThreadPool(bool isMain)
386{
387    LOG_THREADPOOL("**** THREAD %p (PID %d) IS JOINING THE THREAD POOL\n", (void*)pthread_self(), getpid());
388
389    mOut.writeInt32(isMain ? BC_ENTER_LOOPER : BC_REGISTER_LOOPER);
390
391    status_t result;
392    do {
393        int32_t cmd;
394
395        // When we've cleared the incoming command queue, process any pending derefs
396        if (mIn.dataPosition() >= mIn.dataSize()) {
397            size_t numPending = mPendingWeakDerefs.size();
398            if (numPending > 0) {
399                for (size_t i = 0; i < numPending; i++) {
400                    RefBase::weakref_type* refs = mPendingWeakDerefs[i];
401                    refs->decWeak(mProcess.get());
402                }
403                mPendingWeakDerefs.clear();
404            }
405
406            numPending = mPendingStrongDerefs.size();
407            if (numPending > 0) {
408                for (size_t i = 0; i < numPending; i++) {
409                    BBinder* obj = mPendingStrongDerefs[i];
410                    obj->decStrong(mProcess.get());
411                }
412                mPendingStrongDerefs.clear();
413            }
414        }
415
416        // now get the next command to be processed, waiting if necessary
417        result = talkWithDriver();
418        if (result >= NO_ERROR) {
419            size_t IN = mIn.dataAvail();
420            if (IN < sizeof(int32_t)) continue;
421            cmd = mIn.readInt32();
422            IF_LOG_COMMANDS() {
423                alog << "Processing top-level Command: "
424                    << getReturnString(cmd) << endl;
425            }
426            result = executeCommand(cmd);
427        }
428
429        // Let this thread exit the thread pool if it is no longer
430        // needed and it is not the main process thread.
431        if(result == TIMED_OUT && !isMain) {
432            break;
433        }
434    } while (result != -ECONNREFUSED && result != -EBADF);
435
436    LOG_THREADPOOL("**** THREAD %p (PID %d) IS LEAVING THE THREAD POOL err=%p\n",
437        (void*)pthread_self(), getpid(), (void*)result);
438
439    mOut.writeInt32(BC_EXIT_LOOPER);
440    talkWithDriver(false);
441}
442
443void IPCThreadState::stopProcess(bool immediate)
444{
445    //LOGI("**** STOPPING PROCESS");
446    flushCommands();
447    int fd = mProcess->mDriverFD;
448    mProcess->mDriverFD = -1;
449    close(fd);
450    //kill(getpid(), SIGKILL);
451}
452
453status_t IPCThreadState::transact(int32_t handle,
454                                  uint32_t code, const Parcel& data,
455                                  Parcel* reply, uint32_t flags)
456{
457    status_t err = data.errorCheck();
458
459    flags |= TF_ACCEPT_FDS;
460
461    IF_LOG_TRANSACTIONS() {
462        TextOutput::Bundle _b(alog);
463        alog << "BC_TRANSACTION thr " << (void*)pthread_self() << " / hand "
464            << handle << " / code " << TypeCode(code) << ": "
465            << indent << data << dedent << endl;
466    }
467
468    if (err == NO_ERROR) {
469        LOG_ONEWAY(">>>> SEND from pid %d uid %d %s", getpid(), getuid(),
470            (flags & TF_ONE_WAY) == 0 ? "READ REPLY" : "ONE WAY");
471        err = writeTransactionData(BC_TRANSACTION, flags, handle, code, data, NULL);
472    }
473
474    if (err != NO_ERROR) {
475        if (reply) reply->setError(err);
476        return (mLastError = err);
477    }
478
479    if ((flags & TF_ONE_WAY) == 0) {
480        if (reply) {
481            err = waitForResponse(reply);
482        } else {
483            Parcel fakeReply;
484            err = waitForResponse(&fakeReply);
485        }
486
487        IF_LOG_TRANSACTIONS() {
488            TextOutput::Bundle _b(alog);
489            alog << "BR_REPLY thr " << (void*)pthread_self() << " / hand "
490                << handle << ": ";
491            if (reply) alog << indent << *reply << dedent << endl;
492            else alog << "(none requested)" << endl;
493        }
494    } else {
495        err = waitForResponse(NULL, NULL);
496    }
497
498    return err;
499}
500
501void IPCThreadState::incStrongHandle(int32_t handle)
502{
503    LOG_REMOTEREFS("IPCThreadState::incStrongHandle(%d)\n", handle);
504    mOut.writeInt32(BC_ACQUIRE);
505    mOut.writeInt32(handle);
506}
507
508void IPCThreadState::decStrongHandle(int32_t handle)
509{
510    LOG_REMOTEREFS("IPCThreadState::decStrongHandle(%d)\n", handle);
511    mOut.writeInt32(BC_RELEASE);
512    mOut.writeInt32(handle);
513}
514
515void IPCThreadState::incWeakHandle(int32_t handle)
516{
517    LOG_REMOTEREFS("IPCThreadState::incWeakHandle(%d)\n", handle);
518    mOut.writeInt32(BC_INCREFS);
519    mOut.writeInt32(handle);
520}
521
522void IPCThreadState::decWeakHandle(int32_t handle)
523{
524    LOG_REMOTEREFS("IPCThreadState::decWeakHandle(%d)\n", handle);
525    mOut.writeInt32(BC_DECREFS);
526    mOut.writeInt32(handle);
527}
528
529status_t IPCThreadState::attemptIncStrongHandle(int32_t handle)
530{
531    mOut.writeInt32(BC_ATTEMPT_ACQUIRE);
532    mOut.writeInt32(0); // xxx was thread priority
533    mOut.writeInt32(handle);
534    status_t result = UNKNOWN_ERROR;
535
536    waitForResponse(NULL, &result);
537
538#if LOG_REFCOUNTS
539    printf("IPCThreadState::attemptIncStrongHandle(%ld) = %s\n",
540        handle, result == NO_ERROR ? "SUCCESS" : "FAILURE");
541#endif
542
543    return result;
544}
545
546void IPCThreadState::expungeHandle(int32_t handle, IBinder* binder)
547{
548#if LOG_REFCOUNTS
549    printf("IPCThreadState::expungeHandle(%ld)\n", handle);
550#endif
551    self()->mProcess->expungeHandle(handle, binder);
552}
553
554status_t IPCThreadState::requestDeathNotification(int32_t handle, BpBinder* proxy)
555{
556    mOut.writeInt32(BC_REQUEST_DEATH_NOTIFICATION);
557    mOut.writeInt32((int32_t)handle);
558    mOut.writeInt32((int32_t)proxy);
559    return NO_ERROR;
560}
561
562status_t IPCThreadState::clearDeathNotification(int32_t handle, BpBinder* proxy)
563{
564    mOut.writeInt32(BC_CLEAR_DEATH_NOTIFICATION);
565    mOut.writeInt32((int32_t)handle);
566    mOut.writeInt32((int32_t)proxy);
567    return NO_ERROR;
568}
569
570IPCThreadState::IPCThreadState()
571    : mProcess(ProcessState::self())
572{
573    pthread_setspecific(gTLS, this);
574        clearCaller();
575    mIn.setDataCapacity(256);
576    mOut.setDataCapacity(256);
577}
578
579IPCThreadState::~IPCThreadState()
580{
581}
582
583status_t IPCThreadState::sendReply(const Parcel& reply, uint32_t flags)
584{
585    status_t err;
586    status_t statusBuffer;
587    err = writeTransactionData(BC_REPLY, flags, -1, 0, reply, &statusBuffer);
588    if (err < NO_ERROR) return err;
589
590    return waitForResponse(NULL, NULL);
591}
592
593status_t IPCThreadState::waitForResponse(Parcel *reply, status_t *acquireResult)
594{
595    int32_t cmd;
596    int32_t err;
597
598    while (1) {
599        if ((err=talkWithDriver()) < NO_ERROR) break;
600        err = mIn.errorCheck();
601        if (err < NO_ERROR) break;
602        if (mIn.dataAvail() == 0) continue;
603
604        cmd = mIn.readInt32();
605
606        IF_LOG_COMMANDS() {
607            alog << "Processing waitForResponse Command: "
608                << getReturnString(cmd) << endl;
609        }
610
611        switch (cmd) {
612        case BR_TRANSACTION_COMPLETE:
613            if (!reply && !acquireResult) goto finish;
614            break;
615
616        case BR_DEAD_REPLY:
617            err = DEAD_OBJECT;
618            goto finish;
619
620        case BR_FAILED_REPLY:
621            err = FAILED_TRANSACTION;
622            goto finish;
623
624        case BR_ACQUIRE_RESULT:
625            {
626                LOG_ASSERT(acquireResult != NULL, "Unexpected brACQUIRE_RESULT");
627                const int32_t result = mIn.readInt32();
628                if (!acquireResult) continue;
629                *acquireResult = result ? NO_ERROR : INVALID_OPERATION;
630            }
631            goto finish;
632
633        case BR_REPLY:
634            {
635                binder_transaction_data tr;
636                err = mIn.read(&tr, sizeof(tr));
637                LOG_ASSERT(err == NO_ERROR, "Not enough command data for brREPLY");
638                if (err != NO_ERROR) goto finish;
639
640                if (reply) {
641                    if ((tr.flags & TF_STATUS_CODE) == 0) {
642                        reply->ipcSetDataReference(
643                            reinterpret_cast<const uint8_t*>(tr.data.ptr.buffer),
644                            tr.data_size,
645                            reinterpret_cast<const size_t*>(tr.data.ptr.offsets),
646                            tr.offsets_size/sizeof(size_t),
647                            freeBuffer, this);
648                    } else {
649                        err = *static_cast<const status_t*>(tr.data.ptr.buffer);
650                        freeBuffer(NULL,
651                            reinterpret_cast<const uint8_t*>(tr.data.ptr.buffer),
652                            tr.data_size,
653                            reinterpret_cast<const size_t*>(tr.data.ptr.offsets),
654                            tr.offsets_size/sizeof(size_t), this);
655                    }
656                } else {
657                    freeBuffer(NULL,
658                        reinterpret_cast<const uint8_t*>(tr.data.ptr.buffer),
659                        tr.data_size,
660                        reinterpret_cast<const size_t*>(tr.data.ptr.offsets),
661                        tr.offsets_size/sizeof(size_t), this);
662                    continue;
663                }
664            }
665            goto finish;
666
667        default:
668            err = executeCommand(cmd);
669            if (err != NO_ERROR) goto finish;
670            break;
671        }
672    }
673
674finish:
675    if (err != NO_ERROR) {
676        if (acquireResult) *acquireResult = err;
677        if (reply) reply->setError(err);
678        mLastError = err;
679    }
680
681    return err;
682}
683
684status_t IPCThreadState::talkWithDriver(bool doReceive)
685{
686    LOG_ASSERT(mProcess->mDriverFD >= 0, "Binder driver is not opened");
687
688    binder_write_read bwr;
689
690    // Is the read buffer empty?
691    const bool needRead = mIn.dataPosition() >= mIn.dataSize();
692
693    // We don't want to write anything if we are still reading
694    // from data left in the input buffer and the caller
695    // has requested to read the next data.
696    const size_t outAvail = (!doReceive || needRead) ? mOut.dataSize() : 0;
697
698    bwr.write_size = outAvail;
699    bwr.write_buffer = (long unsigned int)mOut.data();
700
701    // This is what we'll read.
702    if (doReceive && needRead) {
703        bwr.read_size = mIn.dataCapacity();
704        bwr.read_buffer = (long unsigned int)mIn.data();
705    } else {
706        bwr.read_size = 0;
707    }
708
709    IF_LOG_COMMANDS() {
710        TextOutput::Bundle _b(alog);
711        if (outAvail != 0) {
712            alog << "Sending commands to driver: " << indent;
713            const void* cmds = (const void*)bwr.write_buffer;
714            const void* end = ((const uint8_t*)cmds)+bwr.write_size;
715            alog << HexDump(cmds, bwr.write_size) << endl;
716            while (cmds < end) cmds = printCommand(alog, cmds);
717            alog << dedent;
718        }
719        alog << "Size of receive buffer: " << bwr.read_size
720            << ", needRead: " << needRead << ", doReceive: " << doReceive << endl;
721    }
722
723    // Return immediately if there is nothing to do.
724    if ((bwr.write_size == 0) && (bwr.read_size == 0)) return NO_ERROR;
725
726    bwr.write_consumed = 0;
727    bwr.read_consumed = 0;
728    status_t err;
729    do {
730        IF_LOG_COMMANDS() {
731            alog << "About to read/write, write size = " << mOut.dataSize() << endl;
732        }
733#if defined(HAVE_ANDROID_OS)
734        if (ioctl(mProcess->mDriverFD, BINDER_WRITE_READ, &bwr) >= 0)
735            err = NO_ERROR;
736        else
737            err = -errno;
738#else
739        err = INVALID_OPERATION;
740#endif
741        IF_LOG_COMMANDS() {
742            alog << "Finished read/write, write size = " << mOut.dataSize() << endl;
743        }
744    } while (err == -EINTR);
745
746    IF_LOG_COMMANDS() {
747        alog << "Our err: " << (void*)err << ", write consumed: "
748            << bwr.write_consumed << " (of " << mOut.dataSize()
749			<< "), read consumed: " << bwr.read_consumed << endl;
750    }
751
752    if (err >= NO_ERROR) {
753        if (bwr.write_consumed > 0) {
754            if (bwr.write_consumed < (ssize_t)mOut.dataSize())
755                mOut.remove(0, bwr.write_consumed);
756            else
757                mOut.setDataSize(0);
758        }
759        if (bwr.read_consumed > 0) {
760            mIn.setDataSize(bwr.read_consumed);
761            mIn.setDataPosition(0);
762        }
763        IF_LOG_COMMANDS() {
764            TextOutput::Bundle _b(alog);
765            alog << "Remaining data size: " << mOut.dataSize() << endl;
766            alog << "Received commands from driver: " << indent;
767            const void* cmds = mIn.data();
768            const void* end = mIn.data() + mIn.dataSize();
769            alog << HexDump(cmds, mIn.dataSize()) << endl;
770            while (cmds < end) cmds = printReturnCommand(alog, cmds);
771            alog << dedent;
772        }
773        return NO_ERROR;
774    }
775
776    return err;
777}
778
779status_t IPCThreadState::writeTransactionData(int32_t cmd, uint32_t binderFlags,
780    int32_t handle, uint32_t code, const Parcel& data, status_t* statusBuffer)
781{
782    binder_transaction_data tr;
783
784    tr.target.handle = handle;
785    tr.code = code;
786    tr.flags = binderFlags;
787
788    const status_t err = data.errorCheck();
789    if (err == NO_ERROR) {
790        tr.data_size = data.ipcDataSize();
791        tr.data.ptr.buffer = data.ipcData();
792        tr.offsets_size = data.ipcObjectsCount()*sizeof(size_t);
793        tr.data.ptr.offsets = data.ipcObjects();
794    } else if (statusBuffer) {
795        tr.flags |= TF_STATUS_CODE;
796        *statusBuffer = err;
797        tr.data_size = sizeof(status_t);
798        tr.data.ptr.buffer = statusBuffer;
799        tr.offsets_size = 0;
800        tr.data.ptr.offsets = NULL;
801    } else {
802        return (mLastError = err);
803    }
804
805    mOut.writeInt32(cmd);
806    mOut.write(&tr, sizeof(tr));
807
808    return NO_ERROR;
809}
810
811sp<BBinder> the_context_object;
812
813void setTheContextObject(sp<BBinder> obj)
814{
815    the_context_object = obj;
816}
817
818status_t IPCThreadState::executeCommand(int32_t cmd)
819{
820    BBinder* obj;
821    RefBase::weakref_type* refs;
822    status_t result = NO_ERROR;
823
824    switch (cmd) {
825    case BR_ERROR:
826        result = mIn.readInt32();
827        break;
828
829    case BR_OK:
830        break;
831
832    case BR_ACQUIRE:
833        refs = (RefBase::weakref_type*)mIn.readInt32();
834        obj = (BBinder*)mIn.readInt32();
835        LOG_ASSERT(refs->refBase() == obj,
836                   "BR_ACQUIRE: object %p does not match cookie %p (expected %p)",
837                   refs, obj, refs->refBase());
838        obj->incStrong(mProcess.get());
839        IF_LOG_REMOTEREFS() {
840            LOG_REMOTEREFS("BR_ACQUIRE from driver on %p", obj);
841            obj->printRefs();
842        }
843        mOut.writeInt32(BC_ACQUIRE_DONE);
844        mOut.writeInt32((int32_t)refs);
845        mOut.writeInt32((int32_t)obj);
846        break;
847
848    case BR_RELEASE:
849        refs = (RefBase::weakref_type*)mIn.readInt32();
850        obj = (BBinder*)mIn.readInt32();
851        LOG_ASSERT(refs->refBase() == obj,
852                   "BR_RELEASE: object %p does not match cookie %p (expected %p)",
853                   refs, obj, refs->refBase());
854        IF_LOG_REMOTEREFS() {
855            LOG_REMOTEREFS("BR_RELEASE from driver on %p", obj);
856            obj->printRefs();
857        }
858        mPendingStrongDerefs.push(obj);
859        break;
860
861    case BR_INCREFS:
862        refs = (RefBase::weakref_type*)mIn.readInt32();
863        obj = (BBinder*)mIn.readInt32();
864        refs->incWeak(mProcess.get());
865        mOut.writeInt32(BC_INCREFS_DONE);
866        mOut.writeInt32((int32_t)refs);
867        mOut.writeInt32((int32_t)obj);
868        break;
869
870    case BR_DECREFS:
871        refs = (RefBase::weakref_type*)mIn.readInt32();
872        obj = (BBinder*)mIn.readInt32();
873        // NOTE: This assertion is not valid, because the object may no
874        // longer exist (thus the (BBinder*)cast above resulting in a different
875        // memory address).
876        //LOG_ASSERT(refs->refBase() == obj,
877        //           "BR_DECREFS: object %p does not match cookie %p (expected %p)",
878        //           refs, obj, refs->refBase());
879        mPendingWeakDerefs.push(refs);
880        break;
881
882    case BR_ATTEMPT_ACQUIRE:
883        refs = (RefBase::weakref_type*)mIn.readInt32();
884        obj = (BBinder*)mIn.readInt32();
885
886        {
887            const bool success = refs->attemptIncStrong(mProcess.get());
888            LOG_ASSERT(success && refs->refBase() == obj,
889                       "BR_ATTEMPT_ACQUIRE: object %p does not match cookie %p (expected %p)",
890                       refs, obj, refs->refBase());
891
892            mOut.writeInt32(BC_ACQUIRE_RESULT);
893            mOut.writeInt32((int32_t)success);
894        }
895        break;
896
897    case BR_TRANSACTION:
898        {
899            binder_transaction_data tr;
900            result = mIn.read(&tr, sizeof(tr));
901            LOG_ASSERT(result == NO_ERROR,
902                "Not enough command data for brTRANSACTION");
903            if (result != NO_ERROR) break;
904
905            Parcel buffer;
906            buffer.ipcSetDataReference(
907                reinterpret_cast<const uint8_t*>(tr.data.ptr.buffer),
908                tr.data_size,
909                reinterpret_cast<const size_t*>(tr.data.ptr.offsets),
910                tr.offsets_size/sizeof(size_t), freeBuffer, this);
911
912            const pid_t origPid = mCallingPid;
913            const uid_t origUid = mCallingUid;
914
915            mCallingPid = tr.sender_pid;
916            mCallingUid = tr.sender_euid;
917
918            //LOGI(">>>> TRANSACT from pid %d uid %d\n", mCallingPid, mCallingUid);
919
920            Parcel reply;
921            IF_LOG_TRANSACTIONS() {
922                TextOutput::Bundle _b(alog);
923                alog << "BR_TRANSACTION thr " << (void*)pthread_self()
924                    << " / obj " << tr.target.ptr << " / code "
925                    << TypeCode(tr.code) << ": " << indent << buffer
926                    << dedent << endl
927                    << "Data addr = "
928                    << reinterpret_cast<const uint8_t*>(tr.data.ptr.buffer)
929                    << ", offsets addr="
930                    << reinterpret_cast<const size_t*>(tr.data.ptr.offsets) << endl;
931            }
932            if (tr.target.ptr) {
933                sp<BBinder> b((BBinder*)tr.cookie);
934                const status_t error = b->transact(tr.code, buffer, &reply, 0);
935                if (error < NO_ERROR) reply.setError(error);
936
937            } else {
938                const status_t error = the_context_object->transact(tr.code, buffer, &reply, 0);
939                if (error < NO_ERROR) reply.setError(error);
940            }
941
942            //LOGI("<<<< TRANSACT from pid %d restore pid %d uid %d\n",
943            //     mCallingPid, origPid, origUid);
944
945            if ((tr.flags & TF_ONE_WAY) == 0) {
946                LOG_ONEWAY("Sending reply to %d!", mCallingPid);
947                sendReply(reply, 0);
948            } else {
949                LOG_ONEWAY("NOT sending reply to %d!", mCallingPid);
950            }
951
952            mCallingPid = origPid;
953            mCallingUid = origUid;
954
955            IF_LOG_TRANSACTIONS() {
956                TextOutput::Bundle _b(alog);
957                alog << "BC_REPLY thr " << (void*)pthread_self() << " / obj "
958                    << tr.target.ptr << ": " << indent << reply << dedent << endl;
959            }
960
961        }
962        break;
963
964    case BR_DEAD_BINDER:
965        {
966            BpBinder *proxy = (BpBinder*)mIn.readInt32();
967            proxy->sendObituary();
968            mOut.writeInt32(BC_DEAD_BINDER_DONE);
969            mOut.writeInt32((int32_t)proxy);
970        } break;
971
972    case BR_CLEAR_DEATH_NOTIFICATION_DONE:
973        {
974            BpBinder *proxy = (BpBinder*)mIn.readInt32();
975            proxy->getWeakRefs()->decWeak(proxy);
976        } break;
977
978    case BR_FINISHED:
979        result = TIMED_OUT;
980        break;
981
982    case BR_NOOP:
983        break;
984
985    case BR_SPAWN_LOOPER:
986        mProcess->spawnPooledThread(false);
987        break;
988
989    default:
990        printf("*** BAD COMMAND %d received from Binder driver\n", cmd);
991        result = UNKNOWN_ERROR;
992        break;
993    }
994
995    if (result != NO_ERROR) {
996        mLastError = result;
997    }
998
999    return result;
1000}
1001
1002void IPCThreadState::threadDestructor(void *st)
1003{
1004	IPCThreadState* const self = static_cast<IPCThreadState*>(st);
1005	if (self) {
1006		self->flushCommands();
1007#if defined(HAVE_ANDROID_OS)
1008        ioctl(self->mProcess->mDriverFD, BINDER_THREAD_EXIT, 0);
1009#endif
1010		delete self;
1011	}
1012}
1013
1014
1015void IPCThreadState::freeBuffer(Parcel* parcel, const uint8_t* data, size_t dataSize,
1016                                const size_t* objects, size_t objectsSize,
1017                                void* cookie)
1018{
1019    //LOGI("Freeing parcel %p", &parcel);
1020    IF_LOG_COMMANDS() {
1021        alog << "Writing BC_FREE_BUFFER for " << data << endl;
1022    }
1023    LOG_ASSERT(data != NULL, "Called with NULL data");
1024    if (parcel != NULL) parcel->closeFileDescriptors();
1025    IPCThreadState* state = self();
1026    state->mOut.writeInt32(BC_FREE_BUFFER);
1027    state->mOut.writeInt32((int32_t)data);
1028}
1029
1030}; // namespace android
1031