IPCThreadState.cpp revision a877cd85b5a026384542e3271fc310d6a8fe24c6 
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_LOG(LOG_VERBOSE, "transact")
60#define IF_LOG_COMMANDS() IF_LOG(LOG_VERBOSE, "ipc")
61#define LOG_REMOTEREFS(...) LOG(LOG_DEBUG, "remoterefs", __VA_ARGS__)
62#define IF_LOG_REMOTEREFS() IF_LOG(LOG_DEBUG, "remoterefs")
63#define LOG_THREADPOOL(...) LOG(LOG_DEBUG, "threadpool", __VA_ARGS__)
64#define LOG_ONEWAY(...) LOG(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#if 1 /* TODO: error update strings */
82    "unknown",
83#else
84    "BR_OK",
85    "BR_TIMEOUT",
86    "BR_WAKEUP",
87    "BR_TRANSACTION",
88    "BR_REPLY",
89    "BR_ACQUIRE_RESULT",
90    "BR_DEAD_REPLY",
91    "BR_TRANSACTION_COMPLETE",
92    "BR_INCREFS",
93    "BR_ACQUIRE",
94    "BR_RELEASE",
95    "BR_DECREFS",
96    "BR_ATTEMPT_ACQUIRE",
97    "BR_EVENT_OCCURRED",
98    "BR_NOOP",
99    "BR_SPAWN_LOOPER",
100    "BR_FINISHED",
101    "BR_DEAD_BINDER",
102    "BR_CLEAR_DEATH_NOTIFICATION_DONE"
103#endif
104};
105
106static const char *kCommandStrings[] = {
107#if 1 /* TODO: error update strings */
108    "unknown",
109#else
110    "BC_NOOP",
111    "BC_TRANSACTION",
112    "BC_REPLY",
113    "BC_ACQUIRE_RESULT",
114    "BC_FREE_BUFFER",
115    "BC_TRANSACTION_COMPLETE",
116    "BC_INCREFS",
117    "BC_ACQUIRE",
118    "BC_RELEASE",
119    "BC_DECREFS",
120    "BC_INCREFS_DONE",
121    "BC_ACQUIRE_DONE",
122    "BC_ATTEMPT_ACQUIRE",
123    "BC_RETRIEVE_ROOT_OBJECT",
124    "BC_SET_THREAD_ENTRY",
125    "BC_REGISTER_LOOPER",
126    "BC_ENTER_LOOPER",
127    "BC_EXIT_LOOPER",
128    "BC_SYNC",
129    "BC_STOP_PROCESS",
130    "BC_STOP_SELF",
131    "BC_REQUEST_DEATH_NOTIFICATION",
132    "BC_CLEAR_DEATH_NOTIFICATION",
133    "BC_DEAD_BINDER_DONE"
134#endif
135};
136
137static const char* getReturnString(size_t idx)
138{
139    if (idx < sizeof(kReturnStrings) / sizeof(kReturnStrings[0]))
140        return kReturnStrings[idx];
141    else
142        return "unknown";
143}
144
145static const char* getCommandString(size_t idx)
146{
147    if (idx < sizeof(kCommandStrings) / sizeof(kCommandStrings[0]))
148        return kCommandStrings[idx];
149    else
150        return "unknown";
151}
152
153static const void* printBinderTransactionData(TextOutput& out, const void* data)
154{
155    const binder_transaction_data* btd =
156        (const binder_transaction_data*)data;
157    out << "target=" << btd->target.ptr << " (cookie " << btd->cookie << ")" << endl
158        << "code=" << TypeCode(btd->code) << ", flags=" << (void*)btd->flags << endl
159        << "data=" << btd->data.ptr.buffer << " (" << (void*)btd->data_size
160        << " bytes)" << endl
161        << "offsets=" << btd->data.ptr.offsets << " (" << (void*)btd->offsets_size
162        << " bytes)" << endl;
163    return btd+1;
164}
165
166static const void* printReturnCommand(TextOutput& out, const void* _cmd)
167{
168    static const int32_t N = sizeof(kReturnStrings)/sizeof(kReturnStrings[0]);
169
170    const int32_t* cmd = (const int32_t*)_cmd;
171    int32_t code = *cmd++;
172    if (code == BR_ERROR) {
173        out << "BR_ERROR: " << (void*)(*cmd++) << endl;
174        return cmd;
175    } else if (code < 0 || code >= N) {
176        out << "Unknown reply: " << code << endl;
177        return cmd;
178    }
179
180    out << kReturnStrings[code];
181    switch (code) {
182        case BR_TRANSACTION:
183        case BR_REPLY: {
184            out << ": " << indent;
185            cmd = (const int32_t *)printBinderTransactionData(out, cmd);
186            out << dedent;
187        } break;
188
189        case BR_ACQUIRE_RESULT: {
190            const int32_t res = *cmd++;
191            out << ": " << res << (res ? " (SUCCESS)" : " (FAILURE)");
192        } break;
193
194        case BR_INCREFS:
195        case BR_ACQUIRE:
196        case BR_RELEASE:
197        case BR_DECREFS: {
198            const int32_t b = *cmd++;
199            const int32_t c = *cmd++;
200            out << ": target=" << (void*)b << " (cookie " << (void*)c << ")";
201        } break;
202
203        case BR_ATTEMPT_ACQUIRE: {
204            const int32_t p = *cmd++;
205            const int32_t b = *cmd++;
206            const int32_t c = *cmd++;
207            out << ": target=" << (void*)b << " (cookie " << (void*)c
208                << "), pri=" << p;
209        } break;
210
211        case BR_DEAD_BINDER:
212        case BR_CLEAR_DEATH_NOTIFICATION_DONE: {
213            const int32_t c = *cmd++;
214            out << ": death cookie " << (void*)c;
215        } break;
216    }
217
218    out << endl;
219    return cmd;
220}
221
222static const void* printCommand(TextOutput& out, const void* _cmd)
223{
224    static const int32_t N = sizeof(kCommandStrings)/sizeof(kCommandStrings[0]);
225
226    const int32_t* cmd = (const int32_t*)_cmd;
227    int32_t code = *cmd++;
228    if (code < 0 || code >= N) {
229        out << "Unknown command: " << code << endl;
230        return cmd;
231    }
232
233    out << kCommandStrings[code];
234    switch (code) {
235        case BC_TRANSACTION:
236        case BC_REPLY: {
237            out << ": " << indent;
238            cmd = (const int32_t *)printBinderTransactionData(out, cmd);
239            out << dedent;
240        } break;
241
242        case BC_ACQUIRE_RESULT: {
243            const int32_t res = *cmd++;
244            out << ": " << res << (res ? " (SUCCESS)" : " (FAILURE)");
245        } break;
246
247        case BC_FREE_BUFFER: {
248            const int32_t buf = *cmd++;
249            out << ": buffer=" << (void*)buf;
250        } break;
251
252        case BC_INCREFS:
253        case BC_ACQUIRE:
254        case BC_RELEASE:
255        case BC_DECREFS: {
256            const int32_t d = *cmd++;
257            out << ": descriptor=" << (void*)d;
258        } break;
259
260        case BC_INCREFS_DONE:
261        case BC_ACQUIRE_DONE: {
262            const int32_t b = *cmd++;
263            const int32_t c = *cmd++;
264            out << ": target=" << (void*)b << " (cookie " << (void*)c << ")";
265        } break;
266
267        case BC_ATTEMPT_ACQUIRE: {
268            const int32_t p = *cmd++;
269            const int32_t d = *cmd++;
270            out << ": decriptor=" << (void*)d << ", pri=" << p;
271        } break;
272
273        case BC_REQUEST_DEATH_NOTIFICATION:
274        case BC_CLEAR_DEATH_NOTIFICATION: {
275            const int32_t h = *cmd++;
276            const int32_t c = *cmd++;
277            out << ": handle=" << h << " (death cookie " << (void*)c << ")";
278        } break;
279
280        case BC_DEAD_BINDER_DONE: {
281            const int32_t c = *cmd++;
282            out << ": death cookie " << (void*)c;
283        } break;
284    }
285
286    out << endl;
287    return cmd;
288}
289#endif
290
291static pthread_mutex_t gTLSMutex = PTHREAD_MUTEX_INITIALIZER;
292static bool gHaveTLS = false;
293static pthread_key_t gTLS = 0;
294static bool gShutdown = false;
295static bool gDisableBackgroundScheduling = false;
296
297IPCThreadState* IPCThreadState::self()
298{
299    if (gHaveTLS) {
300restart:
301        const pthread_key_t k = gTLS;
302        IPCThreadState* st = (IPCThreadState*)pthread_getspecific(k);
303        if (st) return st;
304        return new IPCThreadState;
305    }
306
307    if (gShutdown) return NULL;
308
309    pthread_mutex_lock(&gTLSMutex);
310    if (!gHaveTLS) {
311        if (pthread_key_create(&gTLS, threadDestructor) != 0) {
312            pthread_mutex_unlock(&gTLSMutex);
313            return NULL;
314        }
315        gHaveTLS = true;
316    }
317    pthread_mutex_unlock(&gTLSMutex);
318    goto restart;
319}
320
321void IPCThreadState::shutdown()
322{
323    gShutdown = true;
324
325    if (gHaveTLS) {
326        // XXX Need to wait for all thread pool threads to exit!
327        IPCThreadState* st = (IPCThreadState*)pthread_getspecific(gTLS);
328        if (st) {
329            delete st;
330            pthread_setspecific(gTLS, NULL);
331        }
332        gHaveTLS = false;
333    }
334}
335
336void IPCThreadState::disableBackgroundScheduling(bool disable)
337{
338    gDisableBackgroundScheduling = disable;
339}
340
341sp<ProcessState> IPCThreadState::process()
342{
343    return mProcess;
344}
345
346status_t IPCThreadState::clearLastError()
347{
348    const status_t err = mLastError;
349    mLastError = NO_ERROR;
350    return err;
351}
352
353int IPCThreadState::getCallingPid()
354{
355    return mCallingPid;
356}
357
358int IPCThreadState::getCallingUid()
359{
360    return mCallingUid;
361}
362
363int64_t IPCThreadState::clearCallingIdentity()
364{
365    int64_t token = ((int64_t)mCallingUid<<32) | mCallingPid;
366    clearCaller();
367    return token;
368}
369
370void IPCThreadState::setStrictModePolicy(int32_t policy)
371{
372    mStrictModePolicy = policy;
373}
374
375int32_t IPCThreadState::getStrictModePolicy() const
376{
377    return mStrictModePolicy;
378}
379
380void IPCThreadState::restoreCallingIdentity(int64_t token)
381{
382    mCallingUid = (int)(token>>32);
383    mCallingPid = (int)token;
384}
385
386void IPCThreadState::clearCaller()
387{
388    mCallingPid = getpid();
389    mCallingUid = getuid();
390}
391
392void IPCThreadState::flushCommands()
393{
394    if (mProcess->mDriverFD <= 0)
395        return;
396    talkWithDriver(false);
397}
398
399void IPCThreadState::joinThreadPool(bool isMain)
400{
401    LOG_THREADPOOL("**** THREAD %p (PID %d) IS JOINING THE THREAD POOL\n", (void*)pthread_self(), getpid());
402
403    mOut.writeInt32(isMain ? BC_ENTER_LOOPER : BC_REGISTER_LOOPER);
404
405    // This thread may have been spawned by a thread that was in the background
406    // scheduling group, so first we will make sure it is in the default/foreground
407    // one to avoid performing an initial transaction in the background.
408    androidSetThreadSchedulingGroup(mMyThreadId, ANDROID_TGROUP_DEFAULT);
409
410    status_t result;
411    do {
412        int32_t cmd;
413
414        // When we've cleared the incoming command queue, process any pending derefs
415        if (mIn.dataPosition() >= mIn.dataSize()) {
416            size_t numPending = mPendingWeakDerefs.size();
417            if (numPending > 0) {
418                for (size_t i = 0; i < numPending; i++) {
419                    RefBase::weakref_type* refs = mPendingWeakDerefs[i];
420                    refs->decWeak(mProcess.get());
421                }
422                mPendingWeakDerefs.clear();
423            }
424
425            numPending = mPendingStrongDerefs.size();
426            if (numPending > 0) {
427                for (size_t i = 0; i < numPending; i++) {
428                    BBinder* obj = mPendingStrongDerefs[i];
429                    obj->decStrong(mProcess.get());
430                }
431                mPendingStrongDerefs.clear();
432            }
433        }
434
435        // now get the next command to be processed, waiting if necessary
436        result = talkWithDriver();
437        if (result >= NO_ERROR) {
438            size_t IN = mIn.dataAvail();
439            if (IN < sizeof(int32_t)) continue;
440            cmd = mIn.readInt32();
441            IF_LOG_COMMANDS() {
442                alog << "Processing top-level Command: "
443                    << getReturnString(cmd) << endl;
444            }
445
446
447            result = executeCommand(cmd);
448        }
449
450        // After executing the command, ensure that the thread is returned to the
451        // default cgroup before rejoining the pool.  The driver takes care of
452        // restoring the priority, but doesn't do anything with cgroups so we
453        // need to take care of that here in userspace.  Note that we do make
454        // sure to go in the foreground after executing a transaction, but
455        // there are other callbacks into user code that could have changed
456        // our group so we want to make absolutely sure it is put back.
457        androidSetThreadSchedulingGroup(mMyThreadId, ANDROID_TGROUP_DEFAULT);
458
459        // Let this thread exit the thread pool if it is no longer
460        // needed and it is not the main process thread.
461        if(result == TIMED_OUT && !isMain) {
462            break;
463        }
464    } while (result != -ECONNREFUSED && result != -EBADF);
465
466    LOG_THREADPOOL("**** THREAD %p (PID %d) IS LEAVING THE THREAD POOL err=%p\n",
467        (void*)pthread_self(), getpid(), (void*)result);
468
469    mOut.writeInt32(BC_EXIT_LOOPER);
470    talkWithDriver(false);
471}
472
473void IPCThreadState::stopProcess(bool immediate)
474{
475    //LOGI("**** STOPPING PROCESS");
476    flushCommands();
477    int fd = mProcess->mDriverFD;
478    mProcess->mDriverFD = -1;
479    close(fd);
480    //kill(getpid(), SIGKILL);
481}
482
483status_t IPCThreadState::transact(int32_t handle,
484                                  uint32_t code, const Parcel& data,
485                                  Parcel* reply, uint32_t flags)
486{
487    status_t err = data.errorCheck();
488
489    flags |= TF_ACCEPT_FDS;
490
491    IF_LOG_TRANSACTIONS() {
492        TextOutput::Bundle _b(alog);
493        alog << "BC_TRANSACTION thr " << (void*)pthread_self() << " / hand "
494            << handle << " / code " << TypeCode(code) << ": "
495            << indent << data << dedent << endl;
496    }
497
498    if (err == NO_ERROR) {
499        LOG_ONEWAY(">>>> SEND from pid %d uid %d %s", getpid(), getuid(),
500            (flags & TF_ONE_WAY) == 0 ? "READ REPLY" : "ONE WAY");
501        err = writeTransactionData(BC_TRANSACTION, flags, handle, code, data, NULL);
502    }
503
504    if (err != NO_ERROR) {
505        if (reply) reply->setError(err);
506        return (mLastError = err);
507    }
508
509    if ((flags & TF_ONE_WAY) == 0) {
510        if (reply) {
511            err = waitForResponse(reply);
512        } else {
513            Parcel fakeReply;
514            err = waitForResponse(&fakeReply);
515        }
516
517        IF_LOG_TRANSACTIONS() {
518            TextOutput::Bundle _b(alog);
519            alog << "BR_REPLY thr " << (void*)pthread_self() << " / hand "
520                << handle << ": ";
521            if (reply) alog << indent << *reply << dedent << endl;
522            else alog << "(none requested)" << endl;
523        }
524    } else {
525        err = waitForResponse(NULL, NULL);
526    }
527
528    return err;
529}
530
531void IPCThreadState::incStrongHandle(int32_t handle)
532{
533    LOG_REMOTEREFS("IPCThreadState::incStrongHandle(%d)\n", handle);
534    mOut.writeInt32(BC_ACQUIRE);
535    mOut.writeInt32(handle);
536}
537
538void IPCThreadState::decStrongHandle(int32_t handle)
539{
540    LOG_REMOTEREFS("IPCThreadState::decStrongHandle(%d)\n", handle);
541    mOut.writeInt32(BC_RELEASE);
542    mOut.writeInt32(handle);
543}
544
545void IPCThreadState::incWeakHandle(int32_t handle)
546{
547    LOG_REMOTEREFS("IPCThreadState::incWeakHandle(%d)\n", handle);
548    mOut.writeInt32(BC_INCREFS);
549    mOut.writeInt32(handle);
550}
551
552void IPCThreadState::decWeakHandle(int32_t handle)
553{
554    LOG_REMOTEREFS("IPCThreadState::decWeakHandle(%d)\n", handle);
555    mOut.writeInt32(BC_DECREFS);
556    mOut.writeInt32(handle);
557}
558
559status_t IPCThreadState::attemptIncStrongHandle(int32_t handle)
560{
561    mOut.writeInt32(BC_ATTEMPT_ACQUIRE);
562    mOut.writeInt32(0); // xxx was thread priority
563    mOut.writeInt32(handle);
564    status_t result = UNKNOWN_ERROR;
565
566    waitForResponse(NULL, &result);
567
568#if LOG_REFCOUNTS
569    printf("IPCThreadState::attemptIncStrongHandle(%ld) = %s\n",
570        handle, result == NO_ERROR ? "SUCCESS" : "FAILURE");
571#endif
572
573    return result;
574}
575
576void IPCThreadState::expungeHandle(int32_t handle, IBinder* binder)
577{
578#if LOG_REFCOUNTS
579    printf("IPCThreadState::expungeHandle(%ld)\n", handle);
580#endif
581    self()->mProcess->expungeHandle(handle, binder);
582}
583
584status_t IPCThreadState::requestDeathNotification(int32_t handle, BpBinder* proxy)
585{
586    mOut.writeInt32(BC_REQUEST_DEATH_NOTIFICATION);
587    mOut.writeInt32((int32_t)handle);
588    mOut.writeInt32((int32_t)proxy);
589    return NO_ERROR;
590}
591
592status_t IPCThreadState::clearDeathNotification(int32_t handle, BpBinder* proxy)
593{
594    mOut.writeInt32(BC_CLEAR_DEATH_NOTIFICATION);
595    mOut.writeInt32((int32_t)handle);
596    mOut.writeInt32((int32_t)proxy);
597    return NO_ERROR;
598}
599
600IPCThreadState::IPCThreadState()
601    : mProcess(ProcessState::self()), mMyThreadId(androidGetTid()),
602      mStrictModePolicy(0)
603{
604    pthread_setspecific(gTLS, this);
605    clearCaller();
606    mIn.setDataCapacity(256);
607    mOut.setDataCapacity(256);
608}
609
610IPCThreadState::~IPCThreadState()
611{
612}
613
614status_t IPCThreadState::sendReply(const Parcel& reply, uint32_t flags)
615{
616    status_t err;
617    status_t statusBuffer;
618    err = writeTransactionData(BC_REPLY, flags, -1, 0, reply, &statusBuffer);
619    if (err < NO_ERROR) return err;
620
621    return waitForResponse(NULL, NULL);
622}
623
624status_t IPCThreadState::waitForResponse(Parcel *reply, status_t *acquireResult)
625{
626    int32_t cmd;
627    int32_t err;
628
629    while (1) {
630        if ((err=talkWithDriver()) < NO_ERROR) break;
631        err = mIn.errorCheck();
632        if (err < NO_ERROR) break;
633        if (mIn.dataAvail() == 0) continue;
634
635        cmd = mIn.readInt32();
636
637        IF_LOG_COMMANDS() {
638            alog << "Processing waitForResponse Command: "
639                << getReturnString(cmd) << endl;
640        }
641
642        switch (cmd) {
643        case BR_TRANSACTION_COMPLETE:
644            if (!reply && !acquireResult) goto finish;
645            break;
646
647        case BR_DEAD_REPLY:
648            err = DEAD_OBJECT;
649            goto finish;
650
651        case BR_FAILED_REPLY:
652            err = FAILED_TRANSACTION;
653            goto finish;
654
655        case BR_ACQUIRE_RESULT:
656            {
657                LOG_ASSERT(acquireResult != NULL, "Unexpected brACQUIRE_RESULT");
658                const int32_t result = mIn.readInt32();
659                if (!acquireResult) continue;
660                *acquireResult = result ? NO_ERROR : INVALID_OPERATION;
661            }
662            goto finish;
663
664        case BR_REPLY:
665            {
666                binder_transaction_data tr;
667                err = mIn.read(&tr, sizeof(tr));
668                LOG_ASSERT(err == NO_ERROR, "Not enough command data for brREPLY");
669                if (err != NO_ERROR) goto finish;
670
671                if (reply) {
672                    if ((tr.flags & TF_STATUS_CODE) == 0) {
673                        reply->ipcSetDataReference(
674                            reinterpret_cast<const uint8_t*>(tr.data.ptr.buffer),
675                            tr.data_size,
676                            reinterpret_cast<const size_t*>(tr.data.ptr.offsets),
677                            tr.offsets_size/sizeof(size_t),
678                            freeBuffer, this);
679                    } else {
680                        err = *static_cast<const status_t*>(tr.data.ptr.buffer);
681                        freeBuffer(NULL,
682                            reinterpret_cast<const uint8_t*>(tr.data.ptr.buffer),
683                            tr.data_size,
684                            reinterpret_cast<const size_t*>(tr.data.ptr.offsets),
685                            tr.offsets_size/sizeof(size_t), this);
686                    }
687                } else {
688                    freeBuffer(NULL,
689                        reinterpret_cast<const uint8_t*>(tr.data.ptr.buffer),
690                        tr.data_size,
691                        reinterpret_cast<const size_t*>(tr.data.ptr.offsets),
692                        tr.offsets_size/sizeof(size_t), this);
693                    continue;
694                }
695            }
696            goto finish;
697
698        default:
699            err = executeCommand(cmd);
700            if (err != NO_ERROR) goto finish;
701            break;
702        }
703    }
704
705finish:
706    if (err != NO_ERROR) {
707        if (acquireResult) *acquireResult = err;
708        if (reply) reply->setError(err);
709        mLastError = err;
710    }
711
712    return err;
713}
714
715status_t IPCThreadState::talkWithDriver(bool doReceive)
716{
717    LOG_ASSERT(mProcess->mDriverFD >= 0, "Binder driver is not opened");
718
719    binder_write_read bwr;
720
721    // Is the read buffer empty?
722    const bool needRead = mIn.dataPosition() >= mIn.dataSize();
723
724    // We don't want to write anything if we are still reading
725    // from data left in the input buffer and the caller
726    // has requested to read the next data.
727    const size_t outAvail = (!doReceive || needRead) ? mOut.dataSize() : 0;
728
729    bwr.write_size = outAvail;
730    bwr.write_buffer = (long unsigned int)mOut.data();
731
732    // This is what we'll read.
733    if (doReceive && needRead) {
734        bwr.read_size = mIn.dataCapacity();
735        bwr.read_buffer = (long unsigned int)mIn.data();
736    } else {
737        bwr.read_size = 0;
738    }
739
740    IF_LOG_COMMANDS() {
741        TextOutput::Bundle _b(alog);
742        if (outAvail != 0) {
743            alog << "Sending commands to driver: " << indent;
744            const void* cmds = (const void*)bwr.write_buffer;
745            const void* end = ((const uint8_t*)cmds)+bwr.write_size;
746            alog << HexDump(cmds, bwr.write_size) << endl;
747            while (cmds < end) cmds = printCommand(alog, cmds);
748            alog << dedent;
749        }
750        alog << "Size of receive buffer: " << bwr.read_size
751            << ", needRead: " << needRead << ", doReceive: " << doReceive << endl;
752    }
753
754    // Return immediately if there is nothing to do.
755    if ((bwr.write_size == 0) && (bwr.read_size == 0)) return NO_ERROR;
756
757    bwr.write_consumed = 0;
758    bwr.read_consumed = 0;
759    status_t err;
760    do {
761        IF_LOG_COMMANDS() {
762            alog << "About to read/write, write size = " << mOut.dataSize() << endl;
763        }
764#if defined(HAVE_ANDROID_OS)
765        if (ioctl(mProcess->mDriverFD, BINDER_WRITE_READ, &bwr) >= 0)
766            err = NO_ERROR;
767        else
768            err = -errno;
769#else
770        err = INVALID_OPERATION;
771#endif
772        IF_LOG_COMMANDS() {
773            alog << "Finished read/write, write size = " << mOut.dataSize() << endl;
774        }
775    } while (err == -EINTR);
776
777    IF_LOG_COMMANDS() {
778        alog << "Our err: " << (void*)err << ", write consumed: "
779            << bwr.write_consumed << " (of " << mOut.dataSize()
780			<< "), read consumed: " << bwr.read_consumed << endl;
781    }
782
783    if (err >= NO_ERROR) {
784        if (bwr.write_consumed > 0) {
785            if (bwr.write_consumed < (ssize_t)mOut.dataSize())
786                mOut.remove(0, bwr.write_consumed);
787            else
788                mOut.setDataSize(0);
789        }
790        if (bwr.read_consumed > 0) {
791            mIn.setDataSize(bwr.read_consumed);
792            mIn.setDataPosition(0);
793        }
794        IF_LOG_COMMANDS() {
795            TextOutput::Bundle _b(alog);
796            alog << "Remaining data size: " << mOut.dataSize() << endl;
797            alog << "Received commands from driver: " << indent;
798            const void* cmds = mIn.data();
799            const void* end = mIn.data() + mIn.dataSize();
800            alog << HexDump(cmds, mIn.dataSize()) << endl;
801            while (cmds < end) cmds = printReturnCommand(alog, cmds);
802            alog << dedent;
803        }
804        return NO_ERROR;
805    }
806
807    return err;
808}
809
810status_t IPCThreadState::writeTransactionData(int32_t cmd, uint32_t binderFlags,
811    int32_t handle, uint32_t code, const Parcel& data, status_t* statusBuffer)
812{
813    binder_transaction_data tr;
814
815    tr.target.handle = handle;
816    tr.code = code;
817    tr.flags = binderFlags;
818
819    const status_t err = data.errorCheck();
820    if (err == NO_ERROR) {
821        tr.data_size = data.ipcDataSize();
822        tr.data.ptr.buffer = data.ipcData();
823        tr.offsets_size = data.ipcObjectsCount()*sizeof(size_t);
824        tr.data.ptr.offsets = data.ipcObjects();
825    } else if (statusBuffer) {
826        tr.flags |= TF_STATUS_CODE;
827        *statusBuffer = err;
828        tr.data_size = sizeof(status_t);
829        tr.data.ptr.buffer = statusBuffer;
830        tr.offsets_size = 0;
831        tr.data.ptr.offsets = NULL;
832    } else {
833        return (mLastError = err);
834    }
835
836    mOut.writeInt32(cmd);
837    mOut.write(&tr, sizeof(tr));
838
839    return NO_ERROR;
840}
841
842sp<BBinder> the_context_object;
843
844void setTheContextObject(sp<BBinder> obj)
845{
846    the_context_object = obj;
847}
848
849status_t IPCThreadState::executeCommand(int32_t cmd)
850{
851    BBinder* obj;
852    RefBase::weakref_type* refs;
853    status_t result = NO_ERROR;
854
855    switch (cmd) {
856    case BR_ERROR:
857        result = mIn.readInt32();
858        break;
859
860    case BR_OK:
861        break;
862
863    case BR_ACQUIRE:
864        refs = (RefBase::weakref_type*)mIn.readInt32();
865        obj = (BBinder*)mIn.readInt32();
866        LOG_ASSERT(refs->refBase() == obj,
867                   "BR_ACQUIRE: object %p does not match cookie %p (expected %p)",
868                   refs, obj, refs->refBase());
869        obj->incStrong(mProcess.get());
870        IF_LOG_REMOTEREFS() {
871            LOG_REMOTEREFS("BR_ACQUIRE from driver on %p", obj);
872            obj->printRefs();
873        }
874        mOut.writeInt32(BC_ACQUIRE_DONE);
875        mOut.writeInt32((int32_t)refs);
876        mOut.writeInt32((int32_t)obj);
877        break;
878
879    case BR_RELEASE:
880        refs = (RefBase::weakref_type*)mIn.readInt32();
881        obj = (BBinder*)mIn.readInt32();
882        LOG_ASSERT(refs->refBase() == obj,
883                   "BR_RELEASE: object %p does not match cookie %p (expected %p)",
884                   refs, obj, refs->refBase());
885        IF_LOG_REMOTEREFS() {
886            LOG_REMOTEREFS("BR_RELEASE from driver on %p", obj);
887            obj->printRefs();
888        }
889        mPendingStrongDerefs.push(obj);
890        break;
891
892    case BR_INCREFS:
893        refs = (RefBase::weakref_type*)mIn.readInt32();
894        obj = (BBinder*)mIn.readInt32();
895        refs->incWeak(mProcess.get());
896        mOut.writeInt32(BC_INCREFS_DONE);
897        mOut.writeInt32((int32_t)refs);
898        mOut.writeInt32((int32_t)obj);
899        break;
900
901    case BR_DECREFS:
902        refs = (RefBase::weakref_type*)mIn.readInt32();
903        obj = (BBinder*)mIn.readInt32();
904        // NOTE: This assertion is not valid, because the object may no
905        // longer exist (thus the (BBinder*)cast above resulting in a different
906        // memory address).
907        //LOG_ASSERT(refs->refBase() == obj,
908        //           "BR_DECREFS: object %p does not match cookie %p (expected %p)",
909        //           refs, obj, refs->refBase());
910        mPendingWeakDerefs.push(refs);
911        break;
912
913    case BR_ATTEMPT_ACQUIRE:
914        refs = (RefBase::weakref_type*)mIn.readInt32();
915        obj = (BBinder*)mIn.readInt32();
916
917        {
918            const bool success = refs->attemptIncStrong(mProcess.get());
919            LOG_ASSERT(success && refs->refBase() == obj,
920                       "BR_ATTEMPT_ACQUIRE: object %p does not match cookie %p (expected %p)",
921                       refs, obj, refs->refBase());
922
923            mOut.writeInt32(BC_ACQUIRE_RESULT);
924            mOut.writeInt32((int32_t)success);
925        }
926        break;
927
928    case BR_TRANSACTION:
929        {
930            binder_transaction_data tr;
931            result = mIn.read(&tr, sizeof(tr));
932            LOG_ASSERT(result == NO_ERROR,
933                "Not enough command data for brTRANSACTION");
934            if (result != NO_ERROR) break;
935
936            Parcel buffer;
937            buffer.ipcSetDataReference(
938                reinterpret_cast<const uint8_t*>(tr.data.ptr.buffer),
939                tr.data_size,
940                reinterpret_cast<const size_t*>(tr.data.ptr.offsets),
941                tr.offsets_size/sizeof(size_t), freeBuffer, this);
942
943            const pid_t origPid = mCallingPid;
944            const uid_t origUid = mCallingUid;
945
946            mCallingPid = tr.sender_pid;
947            mCallingUid = tr.sender_euid;
948
949            int curPrio = getpriority(PRIO_PROCESS, mMyThreadId);
950            if (gDisableBackgroundScheduling) {
951                if (curPrio > ANDROID_PRIORITY_NORMAL) {
952                    // We have inherited a reduced priority from the caller, but do not
953                    // want to run in that state in this process.  The driver set our
954                    // priority already (though not our scheduling class), so bounce
955                    // it back to the default before invoking the transaction.
956                    setpriority(PRIO_PROCESS, mMyThreadId, ANDROID_PRIORITY_NORMAL);
957                }
958            } else {
959                if (curPrio >= ANDROID_PRIORITY_BACKGROUND) {
960                    // We want to use the inherited priority from the caller.
961                    // Ensure this thread is in the background scheduling class,
962                    // since the driver won't modify scheduling classes for us.
963                    // The scheduling group is reset to default by the caller
964                    // once this method returns after the transaction is complete.
965                    androidSetThreadSchedulingGroup(mMyThreadId,
966                                                    ANDROID_TGROUP_BG_NONINTERACT);
967                }
968            }
969
970            //LOGI(">>>> TRANSACT from pid %d uid %d\n", mCallingPid, mCallingUid);
971
972            Parcel reply;
973            IF_LOG_TRANSACTIONS() {
974                TextOutput::Bundle _b(alog);
975                alog << "BR_TRANSACTION thr " << (void*)pthread_self()
976                    << " / obj " << tr.target.ptr << " / code "
977                    << TypeCode(tr.code) << ": " << indent << buffer
978                    << dedent << endl
979                    << "Data addr = "
980                    << reinterpret_cast<const uint8_t*>(tr.data.ptr.buffer)
981                    << ", offsets addr="
982                    << reinterpret_cast<const size_t*>(tr.data.ptr.offsets) << endl;
983            }
984            if (tr.target.ptr) {
985                sp<BBinder> b((BBinder*)tr.cookie);
986                const status_t error = b->transact(tr.code, buffer, &reply, 0);
987                if (error < NO_ERROR) reply.setError(error);
988
989            } else {
990                const status_t error = the_context_object->transact(tr.code, buffer, &reply, 0);
991                if (error < NO_ERROR) reply.setError(error);
992            }
993
994            //LOGI("<<<< TRANSACT from pid %d restore pid %d uid %d\n",
995            //     mCallingPid, origPid, origUid);
996
997            if ((tr.flags & TF_ONE_WAY) == 0) {
998                LOG_ONEWAY("Sending reply to %d!", mCallingPid);
999                sendReply(reply, 0);
1000            } else {
1001                LOG_ONEWAY("NOT sending reply to %d!", mCallingPid);
1002            }
1003
1004            mCallingPid = origPid;
1005            mCallingUid = origUid;
1006
1007            IF_LOG_TRANSACTIONS() {
1008                TextOutput::Bundle _b(alog);
1009                alog << "BC_REPLY thr " << (void*)pthread_self() << " / obj "
1010                    << tr.target.ptr << ": " << indent << reply << dedent << endl;
1011            }
1012
1013        }
1014        break;
1015
1016    case BR_DEAD_BINDER:
1017        {
1018            BpBinder *proxy = (BpBinder*)mIn.readInt32();
1019            proxy->sendObituary();
1020            mOut.writeInt32(BC_DEAD_BINDER_DONE);
1021            mOut.writeInt32((int32_t)proxy);
1022        } break;
1023
1024    case BR_CLEAR_DEATH_NOTIFICATION_DONE:
1025        {
1026            BpBinder *proxy = (BpBinder*)mIn.readInt32();
1027            proxy->getWeakRefs()->decWeak(proxy);
1028        } break;
1029
1030    case BR_FINISHED:
1031        result = TIMED_OUT;
1032        break;
1033
1034    case BR_NOOP:
1035        break;
1036
1037    case BR_SPAWN_LOOPER:
1038        mProcess->spawnPooledThread(false);
1039        break;
1040
1041    default:
1042        printf("*** BAD COMMAND %d received from Binder driver\n", cmd);
1043        result = UNKNOWN_ERROR;
1044        break;
1045    }
1046
1047    if (result != NO_ERROR) {
1048        mLastError = result;
1049    }
1050
1051    return result;
1052}
1053
1054void IPCThreadState::threadDestructor(void *st)
1055{
1056	IPCThreadState* const self = static_cast<IPCThreadState*>(st);
1057	if (self) {
1058		self->flushCommands();
1059#if defined(HAVE_ANDROID_OS)
1060        ioctl(self->mProcess->mDriverFD, BINDER_THREAD_EXIT, 0);
1061#endif
1062		delete self;
1063	}
1064}
1065
1066
1067void IPCThreadState::freeBuffer(Parcel* parcel, const uint8_t* data, size_t dataSize,
1068                                const size_t* objects, size_t objectsSize,
1069                                void* cookie)
1070{
1071    //LOGI("Freeing parcel %p", &parcel);
1072    IF_LOG_COMMANDS() {
1073        alog << "Writing BC_FREE_BUFFER for " << data << endl;
1074    }
1075    LOG_ASSERT(data != NULL, "Called with NULL data");
1076    if (parcel != NULL) parcel->closeFileDescriptors();
1077    IPCThreadState* state = self();
1078    state->mOut.writeInt32(BC_FREE_BUFFER);
1079    state->mOut.writeInt32((int32_t)data);
1080}
1081
1082}; // namespace android
1083