IPCThreadState.cpp revision dcd3958c5086f757dc09472700ae7384efea7fc8 
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;
295
296IPCThreadState* IPCThreadState::self()
297{
298    if (gHaveTLS) {
299restart:
300        const pthread_key_t k = gTLS;
301        IPCThreadState* st = (IPCThreadState*)pthread_getspecific(k);
302        if (st) return st;
303        return new IPCThreadState;
304    }
305
306    if (gShutdown) return NULL;
307
308    pthread_mutex_lock(&gTLSMutex);
309    if (!gHaveTLS) {
310        if (pthread_key_create(&gTLS, threadDestructor) != 0) {
311            pthread_mutex_unlock(&gTLSMutex);
312            return NULL;
313        }
314        gHaveTLS = true;
315    }
316    pthread_mutex_unlock(&gTLSMutex);
317    goto restart;
318}
319
320void IPCThreadState::shutdown()
321{
322    gShutdown = true;
323
324    if (gHaveTLS) {
325        // XXX Need to wait for all thread pool threads to exit!
326        IPCThreadState* st = (IPCThreadState*)pthread_getspecific(gTLS);
327        if (st) {
328            delete st;
329            pthread_setspecific(gTLS, NULL);
330        }
331        gHaveTLS = false;
332    }
333}
334
335sp<ProcessState> IPCThreadState::process()
336{
337    return mProcess;
338}
339
340status_t IPCThreadState::clearLastError()
341{
342    const status_t err = mLastError;
343    mLastError = NO_ERROR;
344    return err;
345}
346
347int IPCThreadState::getCallingPid()
348{
349    return mCallingPid;
350}
351
352int IPCThreadState::getCallingUid()
353{
354    return mCallingUid;
355}
356
357int64_t IPCThreadState::clearCallingIdentity()
358{
359    int64_t token = ((int64_t)mCallingUid<<32) | mCallingPid;
360    clearCaller();
361    return token;
362}
363
364void IPCThreadState::restoreCallingIdentity(int64_t token)
365{
366    mCallingUid = (int)(token>>32);
367    mCallingPid = (int)token;
368}
369
370void IPCThreadState::clearCaller()
371{
372    mCallingPid = getpid();
373    mCallingUid = getuid();
374}
375
376void IPCThreadState::flushCommands()
377{
378    if (mProcess->mDriverFD <= 0)
379        return;
380    talkWithDriver(false);
381}
382
383void IPCThreadState::joinThreadPool(bool isMain)
384{
385    LOG_THREADPOOL("**** THREAD %p (PID %d) IS JOINING THE THREAD POOL\n", (void*)pthread_self(), getpid());
386
387    mOut.writeInt32(isMain ? BC_ENTER_LOOPER : BC_REGISTER_LOOPER);
388
389    status_t result;
390    do {
391        int32_t cmd;
392
393        // When we've cleared the incoming command queue, process any pending derefs
394        if (mIn.dataPosition() >= mIn.dataSize()) {
395            size_t numPending = mPendingWeakDerefs.size();
396            if (numPending > 0) {
397                for (size_t i = 0; i < numPending; i++) {
398                    RefBase::weakref_type* refs = mPendingWeakDerefs[i];
399                    refs->decWeak(mProcess.get());
400                }
401                mPendingWeakDerefs.clear();
402            }
403
404            numPending = mPendingStrongDerefs.size();
405            if (numPending > 0) {
406                for (size_t i = 0; i < numPending; i++) {
407                    BBinder* obj = mPendingStrongDerefs[i];
408                    obj->decStrong(mProcess.get());
409                }
410                mPendingStrongDerefs.clear();
411            }
412        }
413
414        // now get the next command to be processed, waiting if necessary
415        result = talkWithDriver();
416        if (result >= NO_ERROR) {
417            size_t IN = mIn.dataAvail();
418            if (IN < sizeof(int32_t)) continue;
419            cmd = mIn.readInt32();
420            IF_LOG_COMMANDS() {
421                alog << "Processing top-level Command: "
422                    << getReturnString(cmd) << endl;
423            }
424
425            bool isTainted = false;
426
427            {
428                SchedPolicy policy;
429                get_sched_policy(getpid(), &policy);
430
431                if (policy == SP_BACKGROUND) {
432                    isTainted = true;
433                }
434            }
435
436            result = executeCommand(cmd);
437
438            // Make sure that after executing the commands that we put the thread back into the
439            // default cgroup.
440            {
441                int pid = getpid();
442                SchedPolicy policy;
443                get_sched_policy(pid, &policy);
444
445                if (!isTainted && policy == SP_BACKGROUND) {
446                    LOGW("*** THREAD %p (PID %p) was left in SP_BACKGROUND with a priority of %d\n",
447                        (void*)pthread_self(), pid, getpriority(PRIO_PROCESS, pid));
448                }
449            }
450        }
451
452        // Let this thread exit the thread pool if it is no longer
453        // needed and it is not the main process thread.
454        if(result == TIMED_OUT && !isMain) {
455            break;
456        }
457    } while (result != -ECONNREFUSED && result != -EBADF);
458
459    LOG_THREADPOOL("**** THREAD %p (PID %d) IS LEAVING THE THREAD POOL err=%p\n",
460        (void*)pthread_self(), getpid(), (void*)result);
461
462    mOut.writeInt32(BC_EXIT_LOOPER);
463    talkWithDriver(false);
464}
465
466void IPCThreadState::stopProcess(bool immediate)
467{
468    //LOGI("**** STOPPING PROCESS");
469    flushCommands();
470    int fd = mProcess->mDriverFD;
471    mProcess->mDriverFD = -1;
472    close(fd);
473    //kill(getpid(), SIGKILL);
474}
475
476status_t IPCThreadState::transact(int32_t handle,
477                                  uint32_t code, const Parcel& data,
478                                  Parcel* reply, uint32_t flags)
479{
480    status_t err = data.errorCheck();
481
482    flags |= TF_ACCEPT_FDS;
483
484    IF_LOG_TRANSACTIONS() {
485        TextOutput::Bundle _b(alog);
486        alog << "BC_TRANSACTION thr " << (void*)pthread_self() << " / hand "
487            << handle << " / code " << TypeCode(code) << ": "
488            << indent << data << dedent << endl;
489    }
490
491    if (err == NO_ERROR) {
492        LOG_ONEWAY(">>>> SEND from pid %d uid %d %s", getpid(), getuid(),
493            (flags & TF_ONE_WAY) == 0 ? "READ REPLY" : "ONE WAY");
494        err = writeTransactionData(BC_TRANSACTION, flags, handle, code, data, NULL);
495    }
496
497    if (err != NO_ERROR) {
498        if (reply) reply->setError(err);
499        return (mLastError = err);
500    }
501
502    if ((flags & TF_ONE_WAY) == 0) {
503        if (reply) {
504            err = waitForResponse(reply);
505        } else {
506            Parcel fakeReply;
507            err = waitForResponse(&fakeReply);
508        }
509
510        IF_LOG_TRANSACTIONS() {
511            TextOutput::Bundle _b(alog);
512            alog << "BR_REPLY thr " << (void*)pthread_self() << " / hand "
513                << handle << ": ";
514            if (reply) alog << indent << *reply << dedent << endl;
515            else alog << "(none requested)" << endl;
516        }
517    } else {
518        err = waitForResponse(NULL, NULL);
519    }
520
521    return err;
522}
523
524void IPCThreadState::incStrongHandle(int32_t handle)
525{
526    LOG_REMOTEREFS("IPCThreadState::incStrongHandle(%d)\n", handle);
527    mOut.writeInt32(BC_ACQUIRE);
528    mOut.writeInt32(handle);
529}
530
531void IPCThreadState::decStrongHandle(int32_t handle)
532{
533    LOG_REMOTEREFS("IPCThreadState::decStrongHandle(%d)\n", handle);
534    mOut.writeInt32(BC_RELEASE);
535    mOut.writeInt32(handle);
536}
537
538void IPCThreadState::incWeakHandle(int32_t handle)
539{
540    LOG_REMOTEREFS("IPCThreadState::incWeakHandle(%d)\n", handle);
541    mOut.writeInt32(BC_INCREFS);
542    mOut.writeInt32(handle);
543}
544
545void IPCThreadState::decWeakHandle(int32_t handle)
546{
547    LOG_REMOTEREFS("IPCThreadState::decWeakHandle(%d)\n", handle);
548    mOut.writeInt32(BC_DECREFS);
549    mOut.writeInt32(handle);
550}
551
552status_t IPCThreadState::attemptIncStrongHandle(int32_t handle)
553{
554    mOut.writeInt32(BC_ATTEMPT_ACQUIRE);
555    mOut.writeInt32(0); // xxx was thread priority
556    mOut.writeInt32(handle);
557    status_t result = UNKNOWN_ERROR;
558
559    waitForResponse(NULL, &result);
560
561#if LOG_REFCOUNTS
562    printf("IPCThreadState::attemptIncStrongHandle(%ld) = %s\n",
563        handle, result == NO_ERROR ? "SUCCESS" : "FAILURE");
564#endif
565
566    return result;
567}
568
569void IPCThreadState::expungeHandle(int32_t handle, IBinder* binder)
570{
571#if LOG_REFCOUNTS
572    printf("IPCThreadState::expungeHandle(%ld)\n", handle);
573#endif
574    self()->mProcess->expungeHandle(handle, binder);
575}
576
577status_t IPCThreadState::requestDeathNotification(int32_t handle, BpBinder* proxy)
578{
579    mOut.writeInt32(BC_REQUEST_DEATH_NOTIFICATION);
580    mOut.writeInt32((int32_t)handle);
581    mOut.writeInt32((int32_t)proxy);
582    return NO_ERROR;
583}
584
585status_t IPCThreadState::clearDeathNotification(int32_t handle, BpBinder* proxy)
586{
587    mOut.writeInt32(BC_CLEAR_DEATH_NOTIFICATION);
588    mOut.writeInt32((int32_t)handle);
589    mOut.writeInt32((int32_t)proxy);
590    return NO_ERROR;
591}
592
593IPCThreadState::IPCThreadState()
594    : mProcess(ProcessState::self())
595{
596    pthread_setspecific(gTLS, this);
597        clearCaller();
598    mIn.setDataCapacity(256);
599    mOut.setDataCapacity(256);
600}
601
602IPCThreadState::~IPCThreadState()
603{
604}
605
606status_t IPCThreadState::sendReply(const Parcel& reply, uint32_t flags)
607{
608    status_t err;
609    status_t statusBuffer;
610    err = writeTransactionData(BC_REPLY, flags, -1, 0, reply, &statusBuffer);
611    if (err < NO_ERROR) return err;
612
613    return waitForResponse(NULL, NULL);
614}
615
616status_t IPCThreadState::waitForResponse(Parcel *reply, status_t *acquireResult)
617{
618    int32_t cmd;
619    int32_t err;
620
621    while (1) {
622        if ((err=talkWithDriver()) < NO_ERROR) break;
623        err = mIn.errorCheck();
624        if (err < NO_ERROR) break;
625        if (mIn.dataAvail() == 0) continue;
626
627        cmd = mIn.readInt32();
628
629        IF_LOG_COMMANDS() {
630            alog << "Processing waitForResponse Command: "
631                << getReturnString(cmd) << endl;
632        }
633
634        switch (cmd) {
635        case BR_TRANSACTION_COMPLETE:
636            if (!reply && !acquireResult) goto finish;
637            break;
638
639        case BR_DEAD_REPLY:
640            err = DEAD_OBJECT;
641            goto finish;
642
643        case BR_FAILED_REPLY:
644            err = FAILED_TRANSACTION;
645            goto finish;
646
647        case BR_ACQUIRE_RESULT:
648            {
649                LOG_ASSERT(acquireResult != NULL, "Unexpected brACQUIRE_RESULT");
650                const int32_t result = mIn.readInt32();
651                if (!acquireResult) continue;
652                *acquireResult = result ? NO_ERROR : INVALID_OPERATION;
653            }
654            goto finish;
655
656        case BR_REPLY:
657            {
658                binder_transaction_data tr;
659                err = mIn.read(&tr, sizeof(tr));
660                LOG_ASSERT(err == NO_ERROR, "Not enough command data for brREPLY");
661                if (err != NO_ERROR) goto finish;
662
663                if (reply) {
664                    if ((tr.flags & TF_STATUS_CODE) == 0) {
665                        reply->ipcSetDataReference(
666                            reinterpret_cast<const uint8_t*>(tr.data.ptr.buffer),
667                            tr.data_size,
668                            reinterpret_cast<const size_t*>(tr.data.ptr.offsets),
669                            tr.offsets_size/sizeof(size_t),
670                            freeBuffer, this);
671                    } else {
672                        err = *static_cast<const status_t*>(tr.data.ptr.buffer);
673                        freeBuffer(NULL,
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), this);
678                    }
679                } else {
680                    freeBuffer(NULL,
681                        reinterpret_cast<const uint8_t*>(tr.data.ptr.buffer),
682                        tr.data_size,
683                        reinterpret_cast<const size_t*>(tr.data.ptr.offsets),
684                        tr.offsets_size/sizeof(size_t), this);
685                    continue;
686                }
687            }
688            goto finish;
689
690        default:
691            err = executeCommand(cmd);
692            if (err != NO_ERROR) goto finish;
693            break;
694        }
695    }
696
697finish:
698    if (err != NO_ERROR) {
699        if (acquireResult) *acquireResult = err;
700        if (reply) reply->setError(err);
701        mLastError = err;
702    }
703
704    return err;
705}
706
707status_t IPCThreadState::talkWithDriver(bool doReceive)
708{
709    LOG_ASSERT(mProcess->mDriverFD >= 0, "Binder driver is not opened");
710
711    binder_write_read bwr;
712
713    // Is the read buffer empty?
714    const bool needRead = mIn.dataPosition() >= mIn.dataSize();
715
716    // We don't want to write anything if we are still reading
717    // from data left in the input buffer and the caller
718    // has requested to read the next data.
719    const size_t outAvail = (!doReceive || needRead) ? mOut.dataSize() : 0;
720
721    bwr.write_size = outAvail;
722    bwr.write_buffer = (long unsigned int)mOut.data();
723
724    // This is what we'll read.
725    if (doReceive && needRead) {
726        bwr.read_size = mIn.dataCapacity();
727        bwr.read_buffer = (long unsigned int)mIn.data();
728    } else {
729        bwr.read_size = 0;
730    }
731
732    IF_LOG_COMMANDS() {
733        TextOutput::Bundle _b(alog);
734        if (outAvail != 0) {
735            alog << "Sending commands to driver: " << indent;
736            const void* cmds = (const void*)bwr.write_buffer;
737            const void* end = ((const uint8_t*)cmds)+bwr.write_size;
738            alog << HexDump(cmds, bwr.write_size) << endl;
739            while (cmds < end) cmds = printCommand(alog, cmds);
740            alog << dedent;
741        }
742        alog << "Size of receive buffer: " << bwr.read_size
743            << ", needRead: " << needRead << ", doReceive: " << doReceive << endl;
744    }
745
746    // Return immediately if there is nothing to do.
747    if ((bwr.write_size == 0) && (bwr.read_size == 0)) return NO_ERROR;
748
749    bwr.write_consumed = 0;
750    bwr.read_consumed = 0;
751    status_t err;
752    do {
753        IF_LOG_COMMANDS() {
754            alog << "About to read/write, write size = " << mOut.dataSize() << endl;
755        }
756#if defined(HAVE_ANDROID_OS)
757        if (ioctl(mProcess->mDriverFD, BINDER_WRITE_READ, &bwr) >= 0)
758            err = NO_ERROR;
759        else
760            err = -errno;
761#else
762        err = INVALID_OPERATION;
763#endif
764        IF_LOG_COMMANDS() {
765            alog << "Finished read/write, write size = " << mOut.dataSize() << endl;
766        }
767    } while (err == -EINTR);
768
769    IF_LOG_COMMANDS() {
770        alog << "Our err: " << (void*)err << ", write consumed: "
771            << bwr.write_consumed << " (of " << mOut.dataSize()
772			<< "), read consumed: " << bwr.read_consumed << endl;
773    }
774
775    if (err >= NO_ERROR) {
776        if (bwr.write_consumed > 0) {
777            if (bwr.write_consumed < (ssize_t)mOut.dataSize())
778                mOut.remove(0, bwr.write_consumed);
779            else
780                mOut.setDataSize(0);
781        }
782        if (bwr.read_consumed > 0) {
783            mIn.setDataSize(bwr.read_consumed);
784            mIn.setDataPosition(0);
785        }
786        IF_LOG_COMMANDS() {
787            TextOutput::Bundle _b(alog);
788            alog << "Remaining data size: " << mOut.dataSize() << endl;
789            alog << "Received commands from driver: " << indent;
790            const void* cmds = mIn.data();
791            const void* end = mIn.data() + mIn.dataSize();
792            alog << HexDump(cmds, mIn.dataSize()) << endl;
793            while (cmds < end) cmds = printReturnCommand(alog, cmds);
794            alog << dedent;
795        }
796        return NO_ERROR;
797    }
798
799    return err;
800}
801
802status_t IPCThreadState::writeTransactionData(int32_t cmd, uint32_t binderFlags,
803    int32_t handle, uint32_t code, const Parcel& data, status_t* statusBuffer)
804{
805    binder_transaction_data tr;
806
807    tr.target.handle = handle;
808    tr.code = code;
809    tr.flags = binderFlags;
810
811    const status_t err = data.errorCheck();
812    if (err == NO_ERROR) {
813        tr.data_size = data.ipcDataSize();
814        tr.data.ptr.buffer = data.ipcData();
815        tr.offsets_size = data.ipcObjectsCount()*sizeof(size_t);
816        tr.data.ptr.offsets = data.ipcObjects();
817    } else if (statusBuffer) {
818        tr.flags |= TF_STATUS_CODE;
819        *statusBuffer = err;
820        tr.data_size = sizeof(status_t);
821        tr.data.ptr.buffer = statusBuffer;
822        tr.offsets_size = 0;
823        tr.data.ptr.offsets = NULL;
824    } else {
825        return (mLastError = err);
826    }
827
828    mOut.writeInt32(cmd);
829    mOut.write(&tr, sizeof(tr));
830
831    return NO_ERROR;
832}
833
834sp<BBinder> the_context_object;
835
836void setTheContextObject(sp<BBinder> obj)
837{
838    the_context_object = obj;
839}
840
841status_t IPCThreadState::executeCommand(int32_t cmd)
842{
843    BBinder* obj;
844    RefBase::weakref_type* refs;
845    status_t result = NO_ERROR;
846
847    switch (cmd) {
848    case BR_ERROR:
849        result = mIn.readInt32();
850        break;
851
852    case BR_OK:
853        break;
854
855    case BR_ACQUIRE:
856        refs = (RefBase::weakref_type*)mIn.readInt32();
857        obj = (BBinder*)mIn.readInt32();
858        LOG_ASSERT(refs->refBase() == obj,
859                   "BR_ACQUIRE: object %p does not match cookie %p (expected %p)",
860                   refs, obj, refs->refBase());
861        obj->incStrong(mProcess.get());
862        IF_LOG_REMOTEREFS() {
863            LOG_REMOTEREFS("BR_ACQUIRE from driver on %p", obj);
864            obj->printRefs();
865        }
866        mOut.writeInt32(BC_ACQUIRE_DONE);
867        mOut.writeInt32((int32_t)refs);
868        mOut.writeInt32((int32_t)obj);
869        break;
870
871    case BR_RELEASE:
872        refs = (RefBase::weakref_type*)mIn.readInt32();
873        obj = (BBinder*)mIn.readInt32();
874        LOG_ASSERT(refs->refBase() == obj,
875                   "BR_RELEASE: object %p does not match cookie %p (expected %p)",
876                   refs, obj, refs->refBase());
877        IF_LOG_REMOTEREFS() {
878            LOG_REMOTEREFS("BR_RELEASE from driver on %p", obj);
879            obj->printRefs();
880        }
881        mPendingStrongDerefs.push(obj);
882        break;
883
884    case BR_INCREFS:
885        refs = (RefBase::weakref_type*)mIn.readInt32();
886        obj = (BBinder*)mIn.readInt32();
887        refs->incWeak(mProcess.get());
888        mOut.writeInt32(BC_INCREFS_DONE);
889        mOut.writeInt32((int32_t)refs);
890        mOut.writeInt32((int32_t)obj);
891        break;
892
893    case BR_DECREFS:
894        refs = (RefBase::weakref_type*)mIn.readInt32();
895        obj = (BBinder*)mIn.readInt32();
896        // NOTE: This assertion is not valid, because the object may no
897        // longer exist (thus the (BBinder*)cast above resulting in a different
898        // memory address).
899        //LOG_ASSERT(refs->refBase() == obj,
900        //           "BR_DECREFS: object %p does not match cookie %p (expected %p)",
901        //           refs, obj, refs->refBase());
902        mPendingWeakDerefs.push(refs);
903        break;
904
905    case BR_ATTEMPT_ACQUIRE:
906        refs = (RefBase::weakref_type*)mIn.readInt32();
907        obj = (BBinder*)mIn.readInt32();
908
909        {
910            const bool success = refs->attemptIncStrong(mProcess.get());
911            LOG_ASSERT(success && refs->refBase() == obj,
912                       "BR_ATTEMPT_ACQUIRE: object %p does not match cookie %p (expected %p)",
913                       refs, obj, refs->refBase());
914
915            mOut.writeInt32(BC_ACQUIRE_RESULT);
916            mOut.writeInt32((int32_t)success);
917        }
918        break;
919
920    case BR_TRANSACTION:
921        {
922            binder_transaction_data tr;
923            result = mIn.read(&tr, sizeof(tr));
924            LOG_ASSERT(result == NO_ERROR,
925                "Not enough command data for brTRANSACTION");
926            if (result != NO_ERROR) break;
927
928            Parcel buffer;
929            buffer.ipcSetDataReference(
930                reinterpret_cast<const uint8_t*>(tr.data.ptr.buffer),
931                tr.data_size,
932                reinterpret_cast<const size_t*>(tr.data.ptr.offsets),
933                tr.offsets_size/sizeof(size_t), freeBuffer, this);
934
935            const pid_t origPid = mCallingPid;
936            const uid_t origUid = mCallingUid;
937
938            mCallingPid = tr.sender_pid;
939            mCallingUid = tr.sender_euid;
940
941            //LOGI(">>>> TRANSACT from pid %d uid %d\n", mCallingPid, mCallingUid);
942
943            Parcel reply;
944            IF_LOG_TRANSACTIONS() {
945                TextOutput::Bundle _b(alog);
946                alog << "BR_TRANSACTION thr " << (void*)pthread_self()
947                    << " / obj " << tr.target.ptr << " / code "
948                    << TypeCode(tr.code) << ": " << indent << buffer
949                    << dedent << endl
950                    << "Data addr = "
951                    << reinterpret_cast<const uint8_t*>(tr.data.ptr.buffer)
952                    << ", offsets addr="
953                    << reinterpret_cast<const size_t*>(tr.data.ptr.offsets) << endl;
954            }
955            if (tr.target.ptr) {
956                sp<BBinder> b((BBinder*)tr.cookie);
957                const status_t error = b->transact(tr.code, buffer, &reply, 0);
958                if (error < NO_ERROR) reply.setError(error);
959
960            } else {
961                const status_t error = the_context_object->transact(tr.code, buffer, &reply, 0);
962                if (error < NO_ERROR) reply.setError(error);
963            }
964
965            //LOGI("<<<< TRANSACT from pid %d restore pid %d uid %d\n",
966            //     mCallingPid, origPid, origUid);
967
968            if ((tr.flags & TF_ONE_WAY) == 0) {
969                LOG_ONEWAY("Sending reply to %d!", mCallingPid);
970                sendReply(reply, 0);
971            } else {
972                LOG_ONEWAY("NOT sending reply to %d!", mCallingPid);
973            }
974
975            mCallingPid = origPid;
976            mCallingUid = origUid;
977
978            IF_LOG_TRANSACTIONS() {
979                TextOutput::Bundle _b(alog);
980                alog << "BC_REPLY thr " << (void*)pthread_self() << " / obj "
981                    << tr.target.ptr << ": " << indent << reply << dedent << endl;
982            }
983
984        }
985        break;
986
987    case BR_DEAD_BINDER:
988        {
989            BpBinder *proxy = (BpBinder*)mIn.readInt32();
990            proxy->sendObituary();
991            mOut.writeInt32(BC_DEAD_BINDER_DONE);
992            mOut.writeInt32((int32_t)proxy);
993        } break;
994
995    case BR_CLEAR_DEATH_NOTIFICATION_DONE:
996        {
997            BpBinder *proxy = (BpBinder*)mIn.readInt32();
998            proxy->getWeakRefs()->decWeak(proxy);
999        } break;
1000
1001    case BR_FINISHED:
1002        result = TIMED_OUT;
1003        break;
1004
1005    case BR_NOOP:
1006        break;
1007
1008    case BR_SPAWN_LOOPER:
1009        mProcess->spawnPooledThread(false);
1010        break;
1011
1012    default:
1013        printf("*** BAD COMMAND %d received from Binder driver\n", cmd);
1014        result = UNKNOWN_ERROR;
1015        break;
1016    }
1017
1018    if (result != NO_ERROR) {
1019        mLastError = result;
1020    }
1021
1022    return result;
1023}
1024
1025void IPCThreadState::threadDestructor(void *st)
1026{
1027	IPCThreadState* const self = static_cast<IPCThreadState*>(st);
1028	if (self) {
1029		self->flushCommands();
1030#if defined(HAVE_ANDROID_OS)
1031        ioctl(self->mProcess->mDriverFD, BINDER_THREAD_EXIT, 0);
1032#endif
1033		delete self;
1034	}
1035}
1036
1037
1038void IPCThreadState::freeBuffer(Parcel* parcel, const uint8_t* data, size_t dataSize,
1039                                const size_t* objects, size_t objectsSize,
1040                                void* cookie)
1041{
1042    //LOGI("Freeing parcel %p", &parcel);
1043    IF_LOG_COMMANDS() {
1044        alog << "Writing BC_FREE_BUFFER for " << data << endl;
1045    }
1046    LOG_ASSERT(data != NULL, "Called with NULL data");
1047    if (parcel != NULL) parcel->closeFileDescriptors();
1048    IPCThreadState* state = self();
1049    state->mOut.writeInt32(BC_FREE_BUFFER);
1050    state->mOut.writeInt32((int32_t)data);
1051}
1052
1053}; // namespace android
1054