IPCThreadState.cpp revision db1597a98958b78dc0d8eced19ae1406382b70d6 
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 <cutils/sched_policy.h>
24#include <utils/Debug.h>
25#include <utils/Log.h>
26#include <utils/TextOutput.h>
27#include <utils/threads.h>
28
29#include <private/binder/binder_module.h>
30#include <private/binder/Static.h>
31
32#include <sys/ioctl.h>
33#include <signal.h>
34#include <errno.h>
35#include <stdio.h>
36#include <unistd.h>
37
38#ifdef HAVE_PTHREADS
39#include <pthread.h>
40#include <sched.h>
41#include <sys/resource.h>
42#endif
43#ifdef HAVE_WIN32_THREADS
44#include <windows.h>
45#endif
46
47
48#if LOG_NDEBUG
49
50#define IF_LOG_TRANSACTIONS() if (false)
51#define IF_LOG_COMMANDS() if (false)
52#define LOG_REMOTEREFS(...)
53#define IF_LOG_REMOTEREFS() if (false)
54#define LOG_THREADPOOL(...)
55#define LOG_ONEWAY(...)
56
57#else
58
59#define IF_LOG_TRANSACTIONS() IF_ALOG(LOG_VERBOSE, "transact")
60#define IF_LOG_COMMANDS() IF_ALOG(LOG_VERBOSE, "ipc")
61#define LOG_REMOTEREFS(...) ALOG(LOG_DEBUG, "remoterefs", __VA_ARGS__)
62#define IF_LOG_REMOTEREFS() IF_ALOG(LOG_DEBUG, "remoterefs")
63#define LOG_THREADPOOL(...) ALOG(LOG_DEBUG, "threadpool", __VA_ARGS__)
64#define LOG_ONEWAY(...) ALOG(LOG_DEBUG, "ipc", __VA_ARGS__)
65
66#endif
67
68// ---------------------------------------------------------------------------
69
70namespace android {
71
72static const char* getReturnString(size_t idx);
73static const char* getCommandString(size_t idx);
74static const void* printReturnCommand(TextOutput& out, const void* _cmd);
75static const void* printCommand(TextOutput& out, const void* _cmd);
76
77// This will result in a missing symbol failure if the IF_LOG_COMMANDS()
78// conditionals don't get stripped...  but that is probably what we want.
79#if !LOG_NDEBUG
80static const char *kReturnStrings[] = {
81    "BR_ERROR",
82    "BR_OK",
83    "BR_TRANSACTION",
84    "BR_REPLY",
85    "BR_ACQUIRE_RESULT",
86    "BR_DEAD_REPLY",
87    "BR_TRANSACTION_COMPLETE",
88    "BR_INCREFS",
89    "BR_ACQUIRE",
90    "BR_RELEASE",
91    "BR_DECREFS",
92    "BR_ATTEMPT_ACQUIRE",
93    "BR_NOOP",
94    "BR_SPAWN_LOOPER",
95    "BR_FINISHED",
96    "BR_DEAD_BINDER",
97    "BR_CLEAR_DEATH_NOTIFICATION_DONE",
98    "BR_FAILED_REPLY"
99};
100
101static const char *kCommandStrings[] = {
102    "BC_TRANSACTION",
103    "BC_REPLY",
104    "BC_ACQUIRE_RESULT",
105    "BC_FREE_BUFFER",
106    "BC_INCREFS",
107    "BC_ACQUIRE",
108    "BC_RELEASE",
109    "BC_DECREFS",
110    "BC_INCREFS_DONE",
111    "BC_ACQUIRE_DONE",
112    "BC_ATTEMPT_ACQUIRE",
113    "BC_REGISTER_LOOPER",
114    "BC_ENTER_LOOPER",
115    "BC_EXIT_LOOPER",
116    "BC_REQUEST_DEATH_NOTIFICATION",
117    "BC_CLEAR_DEATH_NOTIFICATION",
118    "BC_DEAD_BINDER_DONE"
119};
120
121static const char* getReturnString(size_t idx)
122{
123    if (idx < sizeof(kReturnStrings) / sizeof(kReturnStrings[0]))
124        return kReturnStrings[idx];
125    else
126        return "unknown";
127}
128
129static const char* getCommandString(size_t idx)
130{
131    if (idx < sizeof(kCommandStrings) / sizeof(kCommandStrings[0]))
132        return kCommandStrings[idx];
133    else
134        return "unknown";
135}
136
137static const void* printBinderTransactionData(TextOutput& out, const void* data)
138{
139    const binder_transaction_data* btd =
140        (const binder_transaction_data*)data;
141    if (btd->target.handle < 1024) {
142        /* want to print descriptors in decimal; guess based on value */
143        out << "target.desc=" << btd->target.handle;
144    } else {
145        out << "target.ptr=" << btd->target.ptr;
146    }
147    out << " (cookie " << btd->cookie << ")" << endl
148        << "code=" << TypeCode(btd->code) << ", flags=" << (void*)btd->flags << endl
149        << "data=" << btd->data.ptr.buffer << " (" << (void*)btd->data_size
150        << " bytes)" << endl
151        << "offsets=" << btd->data.ptr.offsets << " (" << (void*)btd->offsets_size
152        << " bytes)";
153    return btd+1;
154}
155
156static const void* printReturnCommand(TextOutput& out, const void* _cmd)
157{
158    static const size_t N = sizeof(kReturnStrings)/sizeof(kReturnStrings[0]);
159    const int32_t* cmd = (const int32_t*)_cmd;
160    int32_t code = *cmd++;
161    size_t cmdIndex = code & 0xff;
162    if (code == (int32_t) BR_ERROR) {
163        out << "BR_ERROR: " << (void*)(*cmd++) << endl;
164        return cmd;
165    } else if (cmdIndex >= N) {
166        out << "Unknown reply: " << code << endl;
167        return cmd;
168    }
169    out << kReturnStrings[cmdIndex];
170
171    switch (code) {
172        case BR_TRANSACTION:
173        case BR_REPLY: {
174            out << ": " << indent;
175            cmd = (const int32_t *)printBinderTransactionData(out, cmd);
176            out << dedent;
177        } break;
178
179        case BR_ACQUIRE_RESULT: {
180            const int32_t res = *cmd++;
181            out << ": " << res << (res ? " (SUCCESS)" : " (FAILURE)");
182        } break;
183
184        case BR_INCREFS:
185        case BR_ACQUIRE:
186        case BR_RELEASE:
187        case BR_DECREFS: {
188            const int32_t b = *cmd++;
189            const int32_t c = *cmd++;
190            out << ": target=" << (void*)b << " (cookie " << (void*)c << ")";
191        } break;
192
193        case BR_ATTEMPT_ACQUIRE: {
194            const int32_t p = *cmd++;
195            const int32_t b = *cmd++;
196            const int32_t c = *cmd++;
197            out << ": target=" << (void*)b << " (cookie " << (void*)c
198                << "), pri=" << p;
199        } break;
200
201        case BR_DEAD_BINDER:
202        case BR_CLEAR_DEATH_NOTIFICATION_DONE: {
203            const int32_t c = *cmd++;
204            out << ": death cookie " << (void*)c;
205        } break;
206
207        default:
208            // no details to show for: BR_OK, BR_DEAD_REPLY,
209            // BR_TRANSACTION_COMPLETE, BR_FINISHED
210            break;
211    }
212
213    out << endl;
214    return cmd;
215}
216
217static const void* printCommand(TextOutput& out, const void* _cmd)
218{
219    static const size_t N = sizeof(kCommandStrings)/sizeof(kCommandStrings[0]);
220    const int32_t* cmd = (const int32_t*)_cmd;
221    int32_t code = *cmd++;
222    size_t cmdIndex = code & 0xff;
223
224    if (cmdIndex >= N) {
225        out << "Unknown command: " << code << endl;
226        return cmd;
227    }
228    out << kCommandStrings[cmdIndex];
229
230    switch (code) {
231        case BC_TRANSACTION:
232        case BC_REPLY: {
233            out << ": " << indent;
234            cmd = (const int32_t *)printBinderTransactionData(out, cmd);
235            out << dedent;
236        } break;
237
238        case BC_ACQUIRE_RESULT: {
239            const int32_t res = *cmd++;
240            out << ": " << res << (res ? " (SUCCESS)" : " (FAILURE)");
241        } break;
242
243        case BC_FREE_BUFFER: {
244            const int32_t buf = *cmd++;
245            out << ": buffer=" << (void*)buf;
246        } break;
247
248        case BC_INCREFS:
249        case BC_ACQUIRE:
250        case BC_RELEASE:
251        case BC_DECREFS: {
252            const int32_t d = *cmd++;
253            out << ": desc=" << d;
254        } break;
255
256        case BC_INCREFS_DONE:
257        case BC_ACQUIRE_DONE: {
258            const int32_t b = *cmd++;
259            const int32_t c = *cmd++;
260            out << ": target=" << (void*)b << " (cookie " << (void*)c << ")";
261        } break;
262
263        case BC_ATTEMPT_ACQUIRE: {
264            const int32_t p = *cmd++;
265            const int32_t d = *cmd++;
266            out << ": desc=" << d << ", pri=" << p;
267        } break;
268
269        case BC_REQUEST_DEATH_NOTIFICATION:
270        case BC_CLEAR_DEATH_NOTIFICATION: {
271            const int32_t h = *cmd++;
272            const int32_t c = *cmd++;
273            out << ": handle=" << h << " (death cookie " << (void*)c << ")";
274        } break;
275
276        case BC_DEAD_BINDER_DONE: {
277            const int32_t c = *cmd++;
278            out << ": death cookie " << (void*)c;
279        } break;
280
281        default:
282            // no details to show for: BC_REGISTER_LOOPER, BC_ENTER_LOOPER,
283            // BC_EXIT_LOOPER
284            break;
285    }
286
287    out << endl;
288    return cmd;
289}
290#endif
291
292static pthread_mutex_t gTLSMutex = PTHREAD_MUTEX_INITIALIZER;
293static bool gHaveTLS = false;
294static pthread_key_t gTLS = 0;
295static bool gShutdown = false;
296static bool gDisableBackgroundScheduling = false;
297
298IPCThreadState* IPCThreadState::self()
299{
300    if (gHaveTLS) {
301restart:
302        const pthread_key_t k = gTLS;
303        IPCThreadState* st = (IPCThreadState*)pthread_getspecific(k);
304        if (st) return st;
305        return new IPCThreadState;
306    }
307
308    if (gShutdown) return NULL;
309
310    pthread_mutex_lock(&gTLSMutex);
311    if (!gHaveTLS) {
312        if (pthread_key_create(&gTLS, threadDestructor) != 0) {
313            pthread_mutex_unlock(&gTLSMutex);
314            return NULL;
315        }
316        gHaveTLS = true;
317    }
318    pthread_mutex_unlock(&gTLSMutex);
319    goto restart;
320}
321
322IPCThreadState* IPCThreadState::selfOrNull()
323{
324    if (gHaveTLS) {
325        const pthread_key_t k = gTLS;
326        IPCThreadState* st = (IPCThreadState*)pthread_getspecific(k);
327        return st;
328    }
329    return NULL;
330}
331
332void IPCThreadState::shutdown()
333{
334    gShutdown = true;
335
336    if (gHaveTLS) {
337        // XXX Need to wait for all thread pool threads to exit!
338        IPCThreadState* st = (IPCThreadState*)pthread_getspecific(gTLS);
339        if (st) {
340            delete st;
341            pthread_setspecific(gTLS, NULL);
342        }
343        gHaveTLS = false;
344    }
345}
346
347void IPCThreadState::disableBackgroundScheduling(bool disable)
348{
349    gDisableBackgroundScheduling = disable;
350}
351
352sp<ProcessState> IPCThreadState::process()
353{
354    return mProcess;
355}
356
357status_t IPCThreadState::clearLastError()
358{
359    const status_t err = mLastError;
360    mLastError = NO_ERROR;
361    return err;
362}
363
364int IPCThreadState::getCallingPid()
365{
366    return mCallingPid;
367}
368
369int IPCThreadState::getCallingUid()
370{
371    return mCallingUid;
372}
373
374int IPCThreadState::getOrigCallingUid()
375{
376    return mOrigCallingUid;
377}
378
379int64_t IPCThreadState::clearCallingIdentity()
380{
381    int64_t token = ((int64_t)mCallingUid<<32) | mCallingPid;
382    clearCaller();
383    return token;
384}
385
386void IPCThreadState::setStrictModePolicy(int32_t policy)
387{
388    mStrictModePolicy = policy;
389}
390
391int32_t IPCThreadState::getStrictModePolicy() const
392{
393    return mStrictModePolicy;
394}
395
396void IPCThreadState::setLastTransactionBinderFlags(int32_t flags)
397{
398    mLastTransactionBinderFlags = flags;
399}
400
401int32_t IPCThreadState::getLastTransactionBinderFlags() const
402{
403    return mLastTransactionBinderFlags;
404}
405
406void IPCThreadState::restoreCallingIdentity(int64_t token)
407{
408    mCallingUid = (int)(token>>32);
409    mCallingPid = (int)token;
410}
411
412void IPCThreadState::clearCaller()
413{
414    mCallingPid = getpid();
415    mCallingUid = getuid();
416}
417
418void IPCThreadState::flushCommands()
419{
420    if (mProcess->mDriverFD <= 0)
421        return;
422    talkWithDriver(false);
423}
424
425void IPCThreadState::joinThreadPool(bool isMain)
426{
427    LOG_THREADPOOL("**** THREAD %p (PID %d) IS JOINING THE THREAD POOL\n", (void*)pthread_self(), getpid());
428
429    mOut.writeInt32(isMain ? BC_ENTER_LOOPER : BC_REGISTER_LOOPER);
430
431    // This thread may have been spawned by a thread that was in the background
432    // scheduling group, so first we will make sure it is in the foreground
433    // one to avoid performing an initial transaction in the background.
434    set_sched_policy(mMyThreadId, SP_FOREGROUND);
435
436    status_t result;
437    do {
438        int32_t cmd;
439
440        // When we've cleared the incoming command queue, process any pending derefs
441        if (mIn.dataPosition() >= mIn.dataSize()) {
442            size_t numPending = mPendingWeakDerefs.size();
443            if (numPending > 0) {
444                for (size_t i = 0; i < numPending; i++) {
445                    RefBase::weakref_type* refs = mPendingWeakDerefs[i];
446                    refs->decWeak(mProcess.get());
447                }
448                mPendingWeakDerefs.clear();
449            }
450
451            numPending = mPendingStrongDerefs.size();
452            if (numPending > 0) {
453                for (size_t i = 0; i < numPending; i++) {
454                    BBinder* obj = mPendingStrongDerefs[i];
455                    obj->decStrong(mProcess.get());
456                }
457                mPendingStrongDerefs.clear();
458            }
459        }
460
461        // now get the next command to be processed, waiting if necessary
462        result = talkWithDriver();
463        if (result >= NO_ERROR) {
464            size_t IN = mIn.dataAvail();
465            if (IN < sizeof(int32_t)) continue;
466            cmd = mIn.readInt32();
467            IF_LOG_COMMANDS() {
468                alog << "Processing top-level Command: "
469                    << getReturnString(cmd) << endl;
470            }
471
472
473            result = executeCommand(cmd);
474        }
475
476        // After executing the command, ensure that the thread is returned to the
477        // foreground cgroup before rejoining the pool.  The driver takes care of
478        // restoring the priority, but doesn't do anything with cgroups so we
479        // need to take care of that here in userspace.  Note that we do make
480        // sure to go in the foreground after executing a transaction, but
481        // there are other callbacks into user code that could have changed
482        // our group so we want to make absolutely sure it is put back.
483        set_sched_policy(mMyThreadId, SP_FOREGROUND);
484
485        // Let this thread exit the thread pool if it is no longer
486        // needed and it is not the main process thread.
487        if(result == TIMED_OUT && !isMain) {
488            break;
489        }
490    } while (result != -ECONNREFUSED && result != -EBADF);
491
492    LOG_THREADPOOL("**** THREAD %p (PID %d) IS LEAVING THE THREAD POOL err=%p\n",
493        (void*)pthread_self(), getpid(), (void*)result);
494
495    mOut.writeInt32(BC_EXIT_LOOPER);
496    talkWithDriver(false);
497}
498
499void IPCThreadState::stopProcess(bool immediate)
500{
501    //ALOGI("**** STOPPING PROCESS");
502    flushCommands();
503    int fd = mProcess->mDriverFD;
504    mProcess->mDriverFD = -1;
505    close(fd);
506    //kill(getpid(), SIGKILL);
507}
508
509status_t IPCThreadState::transact(int32_t handle,
510                                  uint32_t code, const Parcel& data,
511                                  Parcel* reply, uint32_t flags)
512{
513    status_t err = data.errorCheck();
514
515    flags |= TF_ACCEPT_FDS;
516
517    IF_LOG_TRANSACTIONS() {
518        TextOutput::Bundle _b(alog);
519        alog << "BC_TRANSACTION thr " << (void*)pthread_self() << " / hand "
520            << handle << " / code " << TypeCode(code) << ": "
521            << indent << data << dedent << endl;
522    }
523
524    if (err == NO_ERROR) {
525        LOG_ONEWAY(">>>> SEND from pid %d uid %d %s", getpid(), getuid(),
526            (flags & TF_ONE_WAY) == 0 ? "READ REPLY" : "ONE WAY");
527        err = writeTransactionData(BC_TRANSACTION, flags, handle, code, data, NULL);
528    }
529
530    if (err != NO_ERROR) {
531        if (reply) reply->setError(err);
532        return (mLastError = err);
533    }
534
535    if ((flags & TF_ONE_WAY) == 0) {
536        #if 0
537        if (code == 4) { // relayout
538            ALOGI(">>>>>> CALLING transaction 4");
539        } else {
540            ALOGI(">>>>>> CALLING transaction %d", code);
541        }
542        #endif
543        if (reply) {
544            err = waitForResponse(reply);
545        } else {
546            Parcel fakeReply;
547            err = waitForResponse(&fakeReply);
548        }
549        #if 0
550        if (code == 4) { // relayout
551            ALOGI("<<<<<< RETURNING transaction 4");
552        } else {
553            ALOGI("<<<<<< RETURNING transaction %d", code);
554        }
555        #endif
556
557        IF_LOG_TRANSACTIONS() {
558            TextOutput::Bundle _b(alog);
559            alog << "BR_REPLY thr " << (void*)pthread_self() << " / hand "
560                << handle << ": ";
561            if (reply) alog << indent << *reply << dedent << endl;
562            else alog << "(none requested)" << endl;
563        }
564    } else {
565        err = waitForResponse(NULL, NULL);
566    }
567
568    return err;
569}
570
571void IPCThreadState::incStrongHandle(int32_t handle)
572{
573    LOG_REMOTEREFS("IPCThreadState::incStrongHandle(%d)\n", handle);
574    mOut.writeInt32(BC_ACQUIRE);
575    mOut.writeInt32(handle);
576}
577
578void IPCThreadState::decStrongHandle(int32_t handle)
579{
580    LOG_REMOTEREFS("IPCThreadState::decStrongHandle(%d)\n", handle);
581    mOut.writeInt32(BC_RELEASE);
582    mOut.writeInt32(handle);
583}
584
585void IPCThreadState::incWeakHandle(int32_t handle)
586{
587    LOG_REMOTEREFS("IPCThreadState::incWeakHandle(%d)\n", handle);
588    mOut.writeInt32(BC_INCREFS);
589    mOut.writeInt32(handle);
590}
591
592void IPCThreadState::decWeakHandle(int32_t handle)
593{
594    LOG_REMOTEREFS("IPCThreadState::decWeakHandle(%d)\n", handle);
595    mOut.writeInt32(BC_DECREFS);
596    mOut.writeInt32(handle);
597}
598
599status_t IPCThreadState::attemptIncStrongHandle(int32_t handle)
600{
601    LOG_REMOTEREFS("IPCThreadState::attemptIncStrongHandle(%d)\n", handle);
602    mOut.writeInt32(BC_ATTEMPT_ACQUIRE);
603    mOut.writeInt32(0); // xxx was thread priority
604    mOut.writeInt32(handle);
605    status_t result = UNKNOWN_ERROR;
606
607    waitForResponse(NULL, &result);
608
609#if LOG_REFCOUNTS
610    printf("IPCThreadState::attemptIncStrongHandle(%ld) = %s\n",
611        handle, result == NO_ERROR ? "SUCCESS" : "FAILURE");
612#endif
613
614    return result;
615}
616
617void IPCThreadState::expungeHandle(int32_t handle, IBinder* binder)
618{
619#if LOG_REFCOUNTS
620    printf("IPCThreadState::expungeHandle(%ld)\n", handle);
621#endif
622    self()->mProcess->expungeHandle(handle, binder);
623}
624
625status_t IPCThreadState::requestDeathNotification(int32_t handle, BpBinder* proxy)
626{
627    mOut.writeInt32(BC_REQUEST_DEATH_NOTIFICATION);
628    mOut.writeInt32((int32_t)handle);
629    mOut.writeInt32((int32_t)proxy);
630    return NO_ERROR;
631}
632
633status_t IPCThreadState::clearDeathNotification(int32_t handle, BpBinder* proxy)
634{
635    mOut.writeInt32(BC_CLEAR_DEATH_NOTIFICATION);
636    mOut.writeInt32((int32_t)handle);
637    mOut.writeInt32((int32_t)proxy);
638    return NO_ERROR;
639}
640
641IPCThreadState::IPCThreadState()
642    : mProcess(ProcessState::self()),
643      mMyThreadId(androidGetTid()),
644      mStrictModePolicy(0),
645      mLastTransactionBinderFlags(0)
646{
647    pthread_setspecific(gTLS, this);
648    clearCaller();
649    mOrigCallingUid = mCallingUid;
650    mIn.setDataCapacity(256);
651    mOut.setDataCapacity(256);
652}
653
654IPCThreadState::~IPCThreadState()
655{
656}
657
658status_t IPCThreadState::sendReply(const Parcel& reply, uint32_t flags)
659{
660    status_t err;
661    status_t statusBuffer;
662    err = writeTransactionData(BC_REPLY, flags, -1, 0, reply, &statusBuffer);
663    if (err < NO_ERROR) return err;
664
665    return waitForResponse(NULL, NULL);
666}
667
668status_t IPCThreadState::waitForResponse(Parcel *reply, status_t *acquireResult)
669{
670    int32_t cmd;
671    int32_t err;
672
673    while (1) {
674        if ((err=talkWithDriver()) < NO_ERROR) break;
675        err = mIn.errorCheck();
676        if (err < NO_ERROR) break;
677        if (mIn.dataAvail() == 0) continue;
678
679        cmd = mIn.readInt32();
680
681        IF_LOG_COMMANDS() {
682            alog << "Processing waitForResponse Command: "
683                << getReturnString(cmd) << endl;
684        }
685
686        switch (cmd) {
687        case BR_TRANSACTION_COMPLETE:
688            if (!reply && !acquireResult) goto finish;
689            break;
690
691        case BR_DEAD_REPLY:
692            err = DEAD_OBJECT;
693            goto finish;
694
695        case BR_FAILED_REPLY:
696            err = FAILED_TRANSACTION;
697            goto finish;
698
699        case BR_ACQUIRE_RESULT:
700            {
701                ALOG_ASSERT(acquireResult != NULL, "Unexpected brACQUIRE_RESULT");
702                const int32_t result = mIn.readInt32();
703                if (!acquireResult) continue;
704                *acquireResult = result ? NO_ERROR : INVALID_OPERATION;
705            }
706            goto finish;
707
708        case BR_REPLY:
709            {
710                binder_transaction_data tr;
711                err = mIn.read(&tr, sizeof(tr));
712                ALOG_ASSERT(err == NO_ERROR, "Not enough command data for brREPLY");
713                if (err != NO_ERROR) goto finish;
714
715                if (reply) {
716                    if ((tr.flags & TF_STATUS_CODE) == 0) {
717                        reply->ipcSetDataReference(
718                            reinterpret_cast<const uint8_t*>(tr.data.ptr.buffer),
719                            tr.data_size,
720                            reinterpret_cast<const size_t*>(tr.data.ptr.offsets),
721                            tr.offsets_size/sizeof(size_t),
722                            freeBuffer, this);
723                    } else {
724                        err = *static_cast<const status_t*>(tr.data.ptr.buffer);
725                        freeBuffer(NULL,
726                            reinterpret_cast<const uint8_t*>(tr.data.ptr.buffer),
727                            tr.data_size,
728                            reinterpret_cast<const size_t*>(tr.data.ptr.offsets),
729                            tr.offsets_size/sizeof(size_t), this);
730                    }
731                } else {
732                    freeBuffer(NULL,
733                        reinterpret_cast<const uint8_t*>(tr.data.ptr.buffer),
734                        tr.data_size,
735                        reinterpret_cast<const size_t*>(tr.data.ptr.offsets),
736                        tr.offsets_size/sizeof(size_t), this);
737                    continue;
738                }
739            }
740            goto finish;
741
742        default:
743            err = executeCommand(cmd);
744            if (err != NO_ERROR) goto finish;
745            break;
746        }
747    }
748
749finish:
750    if (err != NO_ERROR) {
751        if (acquireResult) *acquireResult = err;
752        if (reply) reply->setError(err);
753        mLastError = err;
754    }
755
756    return err;
757}
758
759status_t IPCThreadState::talkWithDriver(bool doReceive)
760{
761    if (mProcess->mDriverFD <= 0) {
762        return -EBADF;
763    }
764
765    binder_write_read bwr;
766
767    // Is the read buffer empty?
768    const bool needRead = mIn.dataPosition() >= mIn.dataSize();
769
770    // We don't want to write anything if we are still reading
771    // from data left in the input buffer and the caller
772    // has requested to read the next data.
773    const size_t outAvail = (!doReceive || needRead) ? mOut.dataSize() : 0;
774
775    bwr.write_size = outAvail;
776    bwr.write_buffer = (long unsigned int)mOut.data();
777
778    // This is what we'll read.
779    if (doReceive && needRead) {
780        bwr.read_size = mIn.dataCapacity();
781        bwr.read_buffer = (long unsigned int)mIn.data();
782    } else {
783        bwr.read_size = 0;
784        bwr.read_buffer = 0;
785    }
786
787    IF_LOG_COMMANDS() {
788        TextOutput::Bundle _b(alog);
789        if (outAvail != 0) {
790            alog << "Sending commands to driver: " << indent;
791            const void* cmds = (const void*)bwr.write_buffer;
792            const void* end = ((const uint8_t*)cmds)+bwr.write_size;
793            alog << HexDump(cmds, bwr.write_size) << endl;
794            while (cmds < end) cmds = printCommand(alog, cmds);
795            alog << dedent;
796        }
797        alog << "Size of receive buffer: " << bwr.read_size
798            << ", needRead: " << needRead << ", doReceive: " << doReceive << endl;
799    }
800
801    // Return immediately if there is nothing to do.
802    if ((bwr.write_size == 0) && (bwr.read_size == 0)) return NO_ERROR;
803
804    bwr.write_consumed = 0;
805    bwr.read_consumed = 0;
806    status_t err;
807    do {
808        IF_LOG_COMMANDS() {
809            alog << "About to read/write, write size = " << mOut.dataSize() << endl;
810        }
811#if defined(HAVE_ANDROID_OS)
812        if (ioctl(mProcess->mDriverFD, BINDER_WRITE_READ, &bwr) >= 0)
813            err = NO_ERROR;
814        else
815            err = -errno;
816#else
817        err = INVALID_OPERATION;
818#endif
819        if (mProcess->mDriverFD <= 0) {
820            err = -EBADF;
821        }
822        IF_LOG_COMMANDS() {
823            alog << "Finished read/write, write size = " << mOut.dataSize() << endl;
824        }
825    } while (err == -EINTR);
826
827    IF_LOG_COMMANDS() {
828        alog << "Our err: " << (void*)err << ", write consumed: "
829            << bwr.write_consumed << " (of " << mOut.dataSize()
830			<< "), read consumed: " << bwr.read_consumed << endl;
831    }
832
833    if (err >= NO_ERROR) {
834        if (bwr.write_consumed > 0) {
835            if (bwr.write_consumed < (ssize_t)mOut.dataSize())
836                mOut.remove(0, bwr.write_consumed);
837            else
838                mOut.setDataSize(0);
839        }
840        if (bwr.read_consumed > 0) {
841            mIn.setDataSize(bwr.read_consumed);
842            mIn.setDataPosition(0);
843        }
844        IF_LOG_COMMANDS() {
845            TextOutput::Bundle _b(alog);
846            alog << "Remaining data size: " << mOut.dataSize() << endl;
847            alog << "Received commands from driver: " << indent;
848            const void* cmds = mIn.data();
849            const void* end = mIn.data() + mIn.dataSize();
850            alog << HexDump(cmds, mIn.dataSize()) << endl;
851            while (cmds < end) cmds = printReturnCommand(alog, cmds);
852            alog << dedent;
853        }
854        return NO_ERROR;
855    }
856
857    return err;
858}
859
860status_t IPCThreadState::writeTransactionData(int32_t cmd, uint32_t binderFlags,
861    int32_t handle, uint32_t code, const Parcel& data, status_t* statusBuffer)
862{
863    binder_transaction_data tr;
864
865    tr.target.handle = handle;
866    tr.code = code;
867    tr.flags = binderFlags;
868    tr.cookie = 0;
869    tr.sender_pid = 0;
870    tr.sender_euid = 0;
871
872    const status_t err = data.errorCheck();
873    if (err == NO_ERROR) {
874        tr.data_size = data.ipcDataSize();
875        tr.data.ptr.buffer = data.ipcData();
876        tr.offsets_size = data.ipcObjectsCount()*sizeof(size_t);
877        tr.data.ptr.offsets = data.ipcObjects();
878    } else if (statusBuffer) {
879        tr.flags |= TF_STATUS_CODE;
880        *statusBuffer = err;
881        tr.data_size = sizeof(status_t);
882        tr.data.ptr.buffer = statusBuffer;
883        tr.offsets_size = 0;
884        tr.data.ptr.offsets = NULL;
885    } else {
886        return (mLastError = err);
887    }
888
889    mOut.writeInt32(cmd);
890    mOut.write(&tr, sizeof(tr));
891
892    return NO_ERROR;
893}
894
895sp<BBinder> the_context_object;
896
897void setTheContextObject(sp<BBinder> obj)
898{
899    the_context_object = obj;
900}
901
902status_t IPCThreadState::executeCommand(int32_t cmd)
903{
904    BBinder* obj;
905    RefBase::weakref_type* refs;
906    status_t result = NO_ERROR;
907
908    switch (cmd) {
909    case BR_ERROR:
910        result = mIn.readInt32();
911        break;
912
913    case BR_OK:
914        break;
915
916    case BR_ACQUIRE:
917        refs = (RefBase::weakref_type*)mIn.readInt32();
918        obj = (BBinder*)mIn.readInt32();
919        ALOG_ASSERT(refs->refBase() == obj,
920                   "BR_ACQUIRE: object %p does not match cookie %p (expected %p)",
921                   refs, obj, refs->refBase());
922        obj->incStrong(mProcess.get());
923        IF_LOG_REMOTEREFS() {
924            LOG_REMOTEREFS("BR_ACQUIRE from driver on %p", obj);
925            obj->printRefs();
926        }
927        mOut.writeInt32(BC_ACQUIRE_DONE);
928        mOut.writeInt32((int32_t)refs);
929        mOut.writeInt32((int32_t)obj);
930        break;
931
932    case BR_RELEASE:
933        refs = (RefBase::weakref_type*)mIn.readInt32();
934        obj = (BBinder*)mIn.readInt32();
935        ALOG_ASSERT(refs->refBase() == obj,
936                   "BR_RELEASE: object %p does not match cookie %p (expected %p)",
937                   refs, obj, refs->refBase());
938        IF_LOG_REMOTEREFS() {
939            LOG_REMOTEREFS("BR_RELEASE from driver on %p", obj);
940            obj->printRefs();
941        }
942        mPendingStrongDerefs.push(obj);
943        break;
944
945    case BR_INCREFS:
946        refs = (RefBase::weakref_type*)mIn.readInt32();
947        obj = (BBinder*)mIn.readInt32();
948        refs->incWeak(mProcess.get());
949        mOut.writeInt32(BC_INCREFS_DONE);
950        mOut.writeInt32((int32_t)refs);
951        mOut.writeInt32((int32_t)obj);
952        break;
953
954    case BR_DECREFS:
955        refs = (RefBase::weakref_type*)mIn.readInt32();
956        obj = (BBinder*)mIn.readInt32();
957        // NOTE: This assertion is not valid, because the object may no
958        // longer exist (thus the (BBinder*)cast above resulting in a different
959        // memory address).
960        //ALOG_ASSERT(refs->refBase() == obj,
961        //           "BR_DECREFS: object %p does not match cookie %p (expected %p)",
962        //           refs, obj, refs->refBase());
963        mPendingWeakDerefs.push(refs);
964        break;
965
966    case BR_ATTEMPT_ACQUIRE:
967        refs = (RefBase::weakref_type*)mIn.readInt32();
968        obj = (BBinder*)mIn.readInt32();
969
970        {
971            const bool success = refs->attemptIncStrong(mProcess.get());
972            ALOG_ASSERT(success && refs->refBase() == obj,
973                       "BR_ATTEMPT_ACQUIRE: object %p does not match cookie %p (expected %p)",
974                       refs, obj, refs->refBase());
975
976            mOut.writeInt32(BC_ACQUIRE_RESULT);
977            mOut.writeInt32((int32_t)success);
978        }
979        break;
980
981    case BR_TRANSACTION:
982        {
983            binder_transaction_data tr;
984            result = mIn.read(&tr, sizeof(tr));
985            ALOG_ASSERT(result == NO_ERROR,
986                "Not enough command data for brTRANSACTION");
987            if (result != NO_ERROR) break;
988
989            Parcel buffer;
990            buffer.ipcSetDataReference(
991                reinterpret_cast<const uint8_t*>(tr.data.ptr.buffer),
992                tr.data_size,
993                reinterpret_cast<const size_t*>(tr.data.ptr.offsets),
994                tr.offsets_size/sizeof(size_t), freeBuffer, this);
995
996            const pid_t origPid = mCallingPid;
997            const uid_t origUid = mCallingUid;
998
999            mCallingPid = tr.sender_pid;
1000            mCallingUid = tr.sender_euid;
1001            mOrigCallingUid = tr.sender_euid;
1002
1003            int curPrio = getpriority(PRIO_PROCESS, mMyThreadId);
1004            if (gDisableBackgroundScheduling) {
1005                if (curPrio > ANDROID_PRIORITY_NORMAL) {
1006                    // We have inherited a reduced priority from the caller, but do not
1007                    // want to run in that state in this process.  The driver set our
1008                    // priority already (though not our scheduling class), so bounce
1009                    // it back to the default before invoking the transaction.
1010                    setpriority(PRIO_PROCESS, mMyThreadId, ANDROID_PRIORITY_NORMAL);
1011                }
1012            } else {
1013                if (curPrio >= ANDROID_PRIORITY_BACKGROUND) {
1014                    // We want to use the inherited priority from the caller.
1015                    // Ensure this thread is in the background scheduling class,
1016                    // since the driver won't modify scheduling classes for us.
1017                    // The scheduling group is reset to default by the caller
1018                    // once this method returns after the transaction is complete.
1019                    set_sched_policy(mMyThreadId, SP_BACKGROUND);
1020                }
1021            }
1022
1023            //ALOGI(">>>> TRANSACT from pid %d uid %d\n", mCallingPid, mCallingUid);
1024
1025            Parcel reply;
1026            IF_LOG_TRANSACTIONS() {
1027                TextOutput::Bundle _b(alog);
1028                alog << "BR_TRANSACTION thr " << (void*)pthread_self()
1029                    << " / obj " << tr.target.ptr << " / code "
1030                    << TypeCode(tr.code) << ": " << indent << buffer
1031                    << dedent << endl
1032                    << "Data addr = "
1033                    << reinterpret_cast<const uint8_t*>(tr.data.ptr.buffer)
1034                    << ", offsets addr="
1035                    << reinterpret_cast<const size_t*>(tr.data.ptr.offsets) << endl;
1036            }
1037            if (tr.target.ptr) {
1038                sp<BBinder> b((BBinder*)tr.cookie);
1039                const status_t error = b->transact(tr.code, buffer, &reply, tr.flags);
1040                if (error < NO_ERROR) reply.setError(error);
1041
1042            } else {
1043                const status_t error = the_context_object->transact(tr.code, buffer, &reply, tr.flags);
1044                if (error < NO_ERROR) reply.setError(error);
1045            }
1046
1047            //ALOGI("<<<< TRANSACT from pid %d restore pid %d uid %d\n",
1048            //     mCallingPid, origPid, origUid);
1049
1050            if ((tr.flags & TF_ONE_WAY) == 0) {
1051                LOG_ONEWAY("Sending reply to %d!", mCallingPid);
1052                sendReply(reply, 0);
1053            } else {
1054                LOG_ONEWAY("NOT sending reply to %d!", mCallingPid);
1055            }
1056
1057            mCallingPid = origPid;
1058            mCallingUid = origUid;
1059            mOrigCallingUid = origUid;
1060
1061            IF_LOG_TRANSACTIONS() {
1062                TextOutput::Bundle _b(alog);
1063                alog << "BC_REPLY thr " << (void*)pthread_self() << " / obj "
1064                    << tr.target.ptr << ": " << indent << reply << dedent << endl;
1065            }
1066
1067        }
1068        break;
1069
1070    case BR_DEAD_BINDER:
1071        {
1072            BpBinder *proxy = (BpBinder*)mIn.readInt32();
1073            proxy->sendObituary();
1074            mOut.writeInt32(BC_DEAD_BINDER_DONE);
1075            mOut.writeInt32((int32_t)proxy);
1076        } break;
1077
1078    case BR_CLEAR_DEATH_NOTIFICATION_DONE:
1079        {
1080            BpBinder *proxy = (BpBinder*)mIn.readInt32();
1081            proxy->getWeakRefs()->decWeak(proxy);
1082        } break;
1083
1084    case BR_FINISHED:
1085        result = TIMED_OUT;
1086        break;
1087
1088    case BR_NOOP:
1089        break;
1090
1091    case BR_SPAWN_LOOPER:
1092        mProcess->spawnPooledThread(false);
1093        break;
1094
1095    default:
1096        printf("*** BAD COMMAND %d received from Binder driver\n", cmd);
1097        result = UNKNOWN_ERROR;
1098        break;
1099    }
1100
1101    if (result != NO_ERROR) {
1102        mLastError = result;
1103    }
1104
1105    return result;
1106}
1107
1108void IPCThreadState::threadDestructor(void *st)
1109{
1110	IPCThreadState* const self = static_cast<IPCThreadState*>(st);
1111	if (self) {
1112		self->flushCommands();
1113#if defined(HAVE_ANDROID_OS)
1114        if (self->mProcess->mDriverFD > 0) {
1115            ioctl(self->mProcess->mDriverFD, BINDER_THREAD_EXIT, 0);
1116        }
1117#endif
1118		delete self;
1119	}
1120}
1121
1122
1123void IPCThreadState::freeBuffer(Parcel* parcel, const uint8_t* data, size_t dataSize,
1124                                const size_t* objects, size_t objectsSize,
1125                                void* cookie)
1126{
1127    //ALOGI("Freeing parcel %p", &parcel);
1128    IF_LOG_COMMANDS() {
1129        alog << "Writing BC_FREE_BUFFER for " << data << endl;
1130    }
1131    ALOG_ASSERT(data != NULL, "Called with NULL data");
1132    if (parcel != NULL) parcel->closeFileDescriptors();
1133    IPCThreadState* state = self();
1134    state->mOut.writeInt32(BC_FREE_BUFFER);
1135    state->mOut.writeInt32((int32_t)data);
1136}
1137
1138}; // namespace android
1139