Parcel.cpp revision fee99040de000a64f6036a7db172fb7c68d9764a 
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 "Parcel"
18//#define LOG_NDEBUG 0
19
20#include <binder/Parcel.h>
21
22#include <binder/IPCThreadState.h>
23#include <binder/Binder.h>
24#include <binder/BpBinder.h>
25#include <binder/ProcessState.h>
26#include <binder/TextOutput.h>
27
28#include <errno.h>
29#include <utils/Debug.h>
30#include <utils/Log.h>
31#include <utils/String8.h>
32#include <utils/String16.h>
33#include <utils/misc.h>
34#include <utils/Flattenable.h>
35#include <cutils/ashmem.h>
36
37#include <private/binder/binder_module.h>
38
39#include <inttypes.h>
40#include <stdio.h>
41#include <stdlib.h>
42#include <stdint.h>
43#include <sys/mman.h>
44
45#ifndef INT32_MAX
46#define INT32_MAX ((int32_t)(2147483647))
47#endif
48
49#define LOG_REFS(...)
50//#define LOG_REFS(...) ALOG(LOG_DEBUG, "Parcel", __VA_ARGS__)
51
52// ---------------------------------------------------------------------------
53
54#define PAD_SIZE(s) (((s)+3)&~3)
55
56// Note: must be kept in sync with android/os/StrictMode.java's PENALTY_GATHER
57#define STRICT_MODE_PENALTY_GATHER 0x100
58
59// Note: must be kept in sync with android/os/Parcel.java's EX_HAS_REPLY_HEADER
60#define EX_HAS_REPLY_HEADER -128
61
62// Maximum size of a blob to transfer in-place.
63static const size_t IN_PLACE_BLOB_LIMIT = 40 * 1024;
64
65// XXX This can be made public if we want to provide
66// support for typed data.
67struct small_flat_data
68{
69    uint32_t type;
70    uint32_t data;
71};
72
73namespace android {
74
75void acquire_object(const sp<ProcessState>& proc,
76    const flat_binder_object& obj, const void* who)
77{
78    switch (obj.type) {
79        case BINDER_TYPE_BINDER:
80            if (obj.binder) {
81                LOG_REFS("Parcel %p acquiring reference on local %p", who, obj.cookie);
82                reinterpret_cast<IBinder*>(obj.cookie)->incStrong(who);
83            }
84            return;
85        case BINDER_TYPE_WEAK_BINDER:
86            if (obj.binder)
87                reinterpret_cast<RefBase::weakref_type*>(obj.binder)->incWeak(who);
88            return;
89        case BINDER_TYPE_HANDLE: {
90            const sp<IBinder> b = proc->getStrongProxyForHandle(obj.handle);
91            if (b != NULL) {
92                LOG_REFS("Parcel %p acquiring reference on remote %p", who, b.get());
93                b->incStrong(who);
94            }
95            return;
96        }
97        case BINDER_TYPE_WEAK_HANDLE: {
98            const wp<IBinder> b = proc->getWeakProxyForHandle(obj.handle);
99            if (b != NULL) b.get_refs()->incWeak(who);
100            return;
101        }
102        case BINDER_TYPE_FD: {
103            // intentionally blank -- nothing to do to acquire this, but we do
104            // recognize it as a legitimate object type.
105            return;
106        }
107    }
108
109    ALOGD("Invalid object type 0x%08x", obj.type);
110}
111
112void release_object(const sp<ProcessState>& proc,
113    const flat_binder_object& obj, const void* who)
114{
115    switch (obj.type) {
116        case BINDER_TYPE_BINDER:
117            if (obj.binder) {
118                LOG_REFS("Parcel %p releasing reference on local %p", who, obj.cookie);
119                reinterpret_cast<IBinder*>(obj.cookie)->decStrong(who);
120            }
121            return;
122        case BINDER_TYPE_WEAK_BINDER:
123            if (obj.binder)
124                reinterpret_cast<RefBase::weakref_type*>(obj.binder)->decWeak(who);
125            return;
126        case BINDER_TYPE_HANDLE: {
127            const sp<IBinder> b = proc->getStrongProxyForHandle(obj.handle);
128            if (b != NULL) {
129                LOG_REFS("Parcel %p releasing reference on remote %p", who, b.get());
130                b->decStrong(who);
131            }
132            return;
133        }
134        case BINDER_TYPE_WEAK_HANDLE: {
135            const wp<IBinder> b = proc->getWeakProxyForHandle(obj.handle);
136            if (b != NULL) b.get_refs()->decWeak(who);
137            return;
138        }
139        case BINDER_TYPE_FD: {
140            if (obj.cookie != 0) close(obj.handle);
141            return;
142        }
143    }
144
145    ALOGE("Invalid object type 0x%08x", obj.type);
146}
147
148inline static status_t finish_flatten_binder(
149    const sp<IBinder>& /*binder*/, const flat_binder_object& flat, Parcel* out)
150{
151    return out->writeObject(flat, false);
152}
153
154status_t flatten_binder(const sp<ProcessState>& /*proc*/,
155    const sp<IBinder>& binder, Parcel* out)
156{
157    flat_binder_object obj;
158
159    obj.flags = 0x7f | FLAT_BINDER_FLAG_ACCEPTS_FDS;
160    if (binder != NULL) {
161        IBinder *local = binder->localBinder();
162        if (!local) {
163            BpBinder *proxy = binder->remoteBinder();
164            if (proxy == NULL) {
165                ALOGE("null proxy");
166            }
167            const int32_t handle = proxy ? proxy->handle() : 0;
168            obj.type = BINDER_TYPE_HANDLE;
169            obj.binder = 0; /* Don't pass uninitialized stack data to a remote process */
170            obj.handle = handle;
171            obj.cookie = 0;
172        } else {
173            obj.type = BINDER_TYPE_BINDER;
174            obj.binder = reinterpret_cast<uintptr_t>(local->getWeakRefs());
175            obj.cookie = reinterpret_cast<uintptr_t>(local);
176        }
177    } else {
178        obj.type = BINDER_TYPE_BINDER;
179        obj.binder = 0;
180        obj.cookie = 0;
181    }
182
183    return finish_flatten_binder(binder, obj, out);
184}
185
186status_t flatten_binder(const sp<ProcessState>& /*proc*/,
187    const wp<IBinder>& binder, Parcel* out)
188{
189    flat_binder_object obj;
190
191    obj.flags = 0x7f | FLAT_BINDER_FLAG_ACCEPTS_FDS;
192    if (binder != NULL) {
193        sp<IBinder> real = binder.promote();
194        if (real != NULL) {
195            IBinder *local = real->localBinder();
196            if (!local) {
197                BpBinder *proxy = real->remoteBinder();
198                if (proxy == NULL) {
199                    ALOGE("null proxy");
200                }
201                const int32_t handle = proxy ? proxy->handle() : 0;
202                obj.type = BINDER_TYPE_WEAK_HANDLE;
203                obj.binder = 0; /* Don't pass uninitialized stack data to a remote process */
204                obj.handle = handle;
205                obj.cookie = 0;
206            } else {
207                obj.type = BINDER_TYPE_WEAK_BINDER;
208                obj.binder = reinterpret_cast<uintptr_t>(binder.get_refs());
209                obj.cookie = reinterpret_cast<uintptr_t>(binder.unsafe_get());
210            }
211            return finish_flatten_binder(real, obj, out);
212        }
213
214        // XXX How to deal?  In order to flatten the given binder,
215        // we need to probe it for information, which requires a primary
216        // reference...  but we don't have one.
217        //
218        // The OpenBinder implementation uses a dynamic_cast<> here,
219        // but we can't do that with the different reference counting
220        // implementation we are using.
221        ALOGE("Unable to unflatten Binder weak reference!");
222        obj.type = BINDER_TYPE_BINDER;
223        obj.binder = 0;
224        obj.cookie = 0;
225        return finish_flatten_binder(NULL, obj, out);
226
227    } else {
228        obj.type = BINDER_TYPE_BINDER;
229        obj.binder = 0;
230        obj.cookie = 0;
231        return finish_flatten_binder(NULL, obj, out);
232    }
233}
234
235inline static status_t finish_unflatten_binder(
236    BpBinder* /*proxy*/, const flat_binder_object& /*flat*/,
237    const Parcel& /*in*/)
238{
239    return NO_ERROR;
240}
241
242status_t unflatten_binder(const sp<ProcessState>& proc,
243    const Parcel& in, sp<IBinder>* out)
244{
245    const flat_binder_object* flat = in.readObject(false);
246
247    if (flat) {
248        switch (flat->type) {
249            case BINDER_TYPE_BINDER:
250                *out = reinterpret_cast<IBinder*>(flat->cookie);
251                return finish_unflatten_binder(NULL, *flat, in);
252            case BINDER_TYPE_HANDLE:
253                *out = proc->getStrongProxyForHandle(flat->handle);
254                return finish_unflatten_binder(
255                    static_cast<BpBinder*>(out->get()), *flat, in);
256        }
257    }
258    return BAD_TYPE;
259}
260
261status_t unflatten_binder(const sp<ProcessState>& proc,
262    const Parcel& in, wp<IBinder>* out)
263{
264    const flat_binder_object* flat = in.readObject(false);
265
266    if (flat) {
267        switch (flat->type) {
268            case BINDER_TYPE_BINDER:
269                *out = reinterpret_cast<IBinder*>(flat->cookie);
270                return finish_unflatten_binder(NULL, *flat, in);
271            case BINDER_TYPE_WEAK_BINDER:
272                if (flat->binder != 0) {
273                    out->set_object_and_refs(
274                        reinterpret_cast<IBinder*>(flat->cookie),
275                        reinterpret_cast<RefBase::weakref_type*>(flat->binder));
276                } else {
277                    *out = NULL;
278                }
279                return finish_unflatten_binder(NULL, *flat, in);
280            case BINDER_TYPE_HANDLE:
281            case BINDER_TYPE_WEAK_HANDLE:
282                *out = proc->getWeakProxyForHandle(flat->handle);
283                return finish_unflatten_binder(
284                    static_cast<BpBinder*>(out->unsafe_get()), *flat, in);
285        }
286    }
287    return BAD_TYPE;
288}
289
290// ---------------------------------------------------------------------------
291
292Parcel::Parcel()
293{
294    initState();
295}
296
297Parcel::~Parcel()
298{
299    freeDataNoInit();
300}
301
302const uint8_t* Parcel::data() const
303{
304    return mData;
305}
306
307size_t Parcel::dataSize() const
308{
309    return (mDataSize > mDataPos ? mDataSize : mDataPos);
310}
311
312size_t Parcel::dataAvail() const
313{
314    // TODO: decide what to do about the possibility that this can
315    // report an available-data size that exceeds a Java int's max
316    // positive value, causing havoc.  Fortunately this will only
317    // happen if someone constructs a Parcel containing more than two
318    // gigabytes of data, which on typical phone hardware is simply
319    // not possible.
320    return dataSize() - dataPosition();
321}
322
323size_t Parcel::dataPosition() const
324{
325    return mDataPos;
326}
327
328size_t Parcel::dataCapacity() const
329{
330    return mDataCapacity;
331}
332
333status_t Parcel::setDataSize(size_t size)
334{
335    status_t err;
336    err = continueWrite(size);
337    if (err == NO_ERROR) {
338        mDataSize = size;
339        ALOGV("setDataSize Setting data size of %p to %zu", this, mDataSize);
340    }
341    return err;
342}
343
344void Parcel::setDataPosition(size_t pos) const
345{
346    mDataPos = pos;
347    mNextObjectHint = 0;
348}
349
350status_t Parcel::setDataCapacity(size_t size)
351{
352    if (size > mDataCapacity) return continueWrite(size);
353    return NO_ERROR;
354}
355
356status_t Parcel::setData(const uint8_t* buffer, size_t len)
357{
358    status_t err = restartWrite(len);
359    if (err == NO_ERROR) {
360        memcpy(const_cast<uint8_t*>(data()), buffer, len);
361        mDataSize = len;
362        mFdsKnown = false;
363    }
364    return err;
365}
366
367status_t Parcel::appendFrom(const Parcel *parcel, size_t offset, size_t len)
368{
369    const sp<ProcessState> proc(ProcessState::self());
370    status_t err;
371    const uint8_t *data = parcel->mData;
372    const binder_size_t *objects = parcel->mObjects;
373    size_t size = parcel->mObjectsSize;
374    int startPos = mDataPos;
375    int firstIndex = -1, lastIndex = -2;
376
377    if (len == 0) {
378        return NO_ERROR;
379    }
380
381    // range checks against the source parcel size
382    if ((offset > parcel->mDataSize)
383            || (len > parcel->mDataSize)
384            || (offset + len > parcel->mDataSize)) {
385        return BAD_VALUE;
386    }
387
388    // Count objects in range
389    for (int i = 0; i < (int) size; i++) {
390        size_t off = objects[i];
391        if ((off >= offset) && (off < offset + len)) {
392            if (firstIndex == -1) {
393                firstIndex = i;
394            }
395            lastIndex = i;
396        }
397    }
398    int numObjects = lastIndex - firstIndex + 1;
399
400    if ((mDataSize+len) > mDataCapacity) {
401        // grow data
402        err = growData(len);
403        if (err != NO_ERROR) {
404            return err;
405        }
406    }
407
408    // append data
409    memcpy(mData + mDataPos, data + offset, len);
410    mDataPos += len;
411    mDataSize += len;
412
413    err = NO_ERROR;
414
415    if (numObjects > 0) {
416        // grow objects
417        if (mObjectsCapacity < mObjectsSize + numObjects) {
418            int newSize = ((mObjectsSize + numObjects)*3)/2;
419            binder_size_t *objects =
420                (binder_size_t*)realloc(mObjects, newSize*sizeof(binder_size_t));
421            if (objects == (binder_size_t*)0) {
422                return NO_MEMORY;
423            }
424            mObjects = objects;
425            mObjectsCapacity = newSize;
426        }
427
428        // append and acquire objects
429        int idx = mObjectsSize;
430        for (int i = firstIndex; i <= lastIndex; i++) {
431            size_t off = objects[i] - offset + startPos;
432            mObjects[idx++] = off;
433            mObjectsSize++;
434
435            flat_binder_object* flat
436                = reinterpret_cast<flat_binder_object*>(mData + off);
437            acquire_object(proc, *flat, this);
438
439            if (flat->type == BINDER_TYPE_FD) {
440                // If this is a file descriptor, we need to dup it so the
441                // new Parcel now owns its own fd, and can declare that we
442                // officially know we have fds.
443                flat->handle = dup(flat->handle);
444                flat->cookie = 1;
445                mHasFds = mFdsKnown = true;
446                if (!mAllowFds) {
447                    err = FDS_NOT_ALLOWED;
448                }
449            }
450        }
451    }
452
453    return err;
454}
455
456bool Parcel::pushAllowFds(bool allowFds)
457{
458    const bool origValue = mAllowFds;
459    if (!allowFds) {
460        mAllowFds = false;
461    }
462    return origValue;
463}
464
465void Parcel::restoreAllowFds(bool lastValue)
466{
467    mAllowFds = lastValue;
468}
469
470bool Parcel::hasFileDescriptors() const
471{
472    if (!mFdsKnown) {
473        scanForFds();
474    }
475    return mHasFds;
476}
477
478// Write RPC headers.  (previously just the interface token)
479status_t Parcel::writeInterfaceToken(const String16& interface)
480{
481    writeInt32(IPCThreadState::self()->getStrictModePolicy() |
482               STRICT_MODE_PENALTY_GATHER);
483    // currently the interface identification token is just its name as a string
484    return writeString16(interface);
485}
486
487bool Parcel::checkInterface(IBinder* binder) const
488{
489    return enforceInterface(binder->getInterfaceDescriptor());
490}
491
492bool Parcel::enforceInterface(const String16& interface,
493                              IPCThreadState* threadState) const
494{
495    int32_t strictPolicy = readInt32();
496    if (threadState == NULL) {
497        threadState = IPCThreadState::self();
498    }
499    if ((threadState->getLastTransactionBinderFlags() &
500         IBinder::FLAG_ONEWAY) != 0) {
501      // For one-way calls, the callee is running entirely
502      // disconnected from the caller, so disable StrictMode entirely.
503      // Not only does disk/network usage not impact the caller, but
504      // there's no way to commuicate back any violations anyway.
505      threadState->setStrictModePolicy(0);
506    } else {
507      threadState->setStrictModePolicy(strictPolicy);
508    }
509    const String16 str(readString16());
510    if (str == interface) {
511        return true;
512    } else {
513        ALOGW("**** enforceInterface() expected '%s' but read '%s'",
514                String8(interface).string(), String8(str).string());
515        return false;
516    }
517}
518
519const binder_size_t* Parcel::objects() const
520{
521    return mObjects;
522}
523
524size_t Parcel::objectsCount() const
525{
526    return mObjectsSize;
527}
528
529status_t Parcel::errorCheck() const
530{
531    return mError;
532}
533
534void Parcel::setError(status_t err)
535{
536    mError = err;
537}
538
539status_t Parcel::finishWrite(size_t len)
540{
541    //printf("Finish write of %d\n", len);
542    mDataPos += len;
543    ALOGV("finishWrite Setting data pos of %p to %zu", this, mDataPos);
544    if (mDataPos > mDataSize) {
545        mDataSize = mDataPos;
546        ALOGV("finishWrite Setting data size of %p to %zu", this, mDataSize);
547    }
548    //printf("New pos=%d, size=%d\n", mDataPos, mDataSize);
549    return NO_ERROR;
550}
551
552status_t Parcel::writeUnpadded(const void* data, size_t len)
553{
554    size_t end = mDataPos + len;
555    if (end < mDataPos) {
556        // integer overflow
557        return BAD_VALUE;
558    }
559
560    if (end <= mDataCapacity) {
561restart_write:
562        memcpy(mData+mDataPos, data, len);
563        return finishWrite(len);
564    }
565
566    status_t err = growData(len);
567    if (err == NO_ERROR) goto restart_write;
568    return err;
569}
570
571status_t Parcel::write(const void* data, size_t len)
572{
573    void* const d = writeInplace(len);
574    if (d) {
575        memcpy(d, data, len);
576        return NO_ERROR;
577    }
578    return mError;
579}
580
581void* Parcel::writeInplace(size_t len)
582{
583    const size_t padded = PAD_SIZE(len);
584
585    // sanity check for integer overflow
586    if (mDataPos+padded < mDataPos) {
587        return NULL;
588    }
589
590    if ((mDataPos+padded) <= mDataCapacity) {
591restart_write:
592        //printf("Writing %ld bytes, padded to %ld\n", len, padded);
593        uint8_t* const data = mData+mDataPos;
594
595        // Need to pad at end?
596        if (padded != len) {
597#if BYTE_ORDER == BIG_ENDIAN
598            static const uint32_t mask[4] = {
599                0x00000000, 0xffffff00, 0xffff0000, 0xff000000
600            };
601#endif
602#if BYTE_ORDER == LITTLE_ENDIAN
603            static const uint32_t mask[4] = {
604                0x00000000, 0x00ffffff, 0x0000ffff, 0x000000ff
605            };
606#endif
607            //printf("Applying pad mask: %p to %p\n", (void*)mask[padded-len],
608            //    *reinterpret_cast<void**>(data+padded-4));
609            *reinterpret_cast<uint32_t*>(data+padded-4) &= mask[padded-len];
610        }
611
612        finishWrite(padded);
613        return data;
614    }
615
616    status_t err = growData(padded);
617    if (err == NO_ERROR) goto restart_write;
618    return NULL;
619}
620
621status_t Parcel::writeInt32(int32_t val)
622{
623    return writeAligned(val);
624}
625status_t Parcel::writeInt32Array(size_t len, const int32_t *val) {
626    if (!val) {
627        return writeAligned(-1);
628    }
629    status_t ret = writeAligned(len);
630    if (ret == NO_ERROR) {
631        ret = write(val, len * sizeof(*val));
632    }
633    return ret;
634}
635status_t Parcel::writeByteArray(size_t len, const uint8_t *val) {
636    if (!val) {
637        return writeAligned(-1);
638    }
639    status_t ret = writeAligned(len);
640    if (ret == NO_ERROR) {
641        ret = write(val, len * sizeof(*val));
642    }
643    return ret;
644}
645
646status_t Parcel::writeInt64(int64_t val)
647{
648    return writeAligned(val);
649}
650
651status_t Parcel::writePointer(uintptr_t val)
652{
653    return writeAligned<binder_uintptr_t>(val);
654}
655
656status_t Parcel::writeFloat(float val)
657{
658    return writeAligned(val);
659}
660
661#if defined(__mips__) && defined(__mips_hard_float)
662
663status_t Parcel::writeDouble(double val)
664{
665    union {
666        double d;
667        unsigned long long ll;
668    } u;
669    u.d = val;
670    return writeAligned(u.ll);
671}
672
673#else
674
675status_t Parcel::writeDouble(double val)
676{
677    return writeAligned(val);
678}
679
680#endif
681
682status_t Parcel::writeCString(const char* str)
683{
684    return write(str, strlen(str)+1);
685}
686
687status_t Parcel::writeString8(const String8& str)
688{
689    status_t err = writeInt32(str.bytes());
690    // only write string if its length is more than zero characters,
691    // as readString8 will only read if the length field is non-zero.
692    // this is slightly different from how writeString16 works.
693    if (str.bytes() > 0 && err == NO_ERROR) {
694        err = write(str.string(), str.bytes()+1);
695    }
696    return err;
697}
698
699status_t Parcel::writeString16(const String16& str)
700{
701    return writeString16(str.string(), str.size());
702}
703
704status_t Parcel::writeString16(const char16_t* str, size_t len)
705{
706    if (str == NULL) return writeInt32(-1);
707
708    status_t err = writeInt32(len);
709    if (err == NO_ERROR) {
710        len *= sizeof(char16_t);
711        uint8_t* data = (uint8_t*)writeInplace(len+sizeof(char16_t));
712        if (data) {
713            memcpy(data, str, len);
714            *reinterpret_cast<char16_t*>(data+len) = 0;
715            return NO_ERROR;
716        }
717        err = mError;
718    }
719    return err;
720}
721
722status_t Parcel::writeStrongBinder(const sp<IBinder>& val)
723{
724    return flatten_binder(ProcessState::self(), val, this);
725}
726
727status_t Parcel::writeWeakBinder(const wp<IBinder>& val)
728{
729    return flatten_binder(ProcessState::self(), val, this);
730}
731
732status_t Parcel::writeNativeHandle(const native_handle* handle)
733{
734    if (!handle || handle->version != sizeof(native_handle))
735        return BAD_TYPE;
736
737    status_t err;
738    err = writeInt32(handle->numFds);
739    if (err != NO_ERROR) return err;
740
741    err = writeInt32(handle->numInts);
742    if (err != NO_ERROR) return err;
743
744    for (int i=0 ; err==NO_ERROR && i<handle->numFds ; i++)
745        err = writeDupFileDescriptor(handle->data[i]);
746
747    if (err != NO_ERROR) {
748        ALOGD("write native handle, write dup fd failed");
749        return err;
750    }
751    err = write(handle->data + handle->numFds, sizeof(int)*handle->numInts);
752    return err;
753}
754
755status_t Parcel::writeFileDescriptor(int fd, bool takeOwnership)
756{
757    flat_binder_object obj;
758    obj.type = BINDER_TYPE_FD;
759    obj.flags = 0x7f | FLAT_BINDER_FLAG_ACCEPTS_FDS;
760    obj.binder = 0; /* Don't pass uninitialized stack data to a remote process */
761    obj.handle = fd;
762    obj.cookie = takeOwnership ? 1 : 0;
763    return writeObject(obj, true);
764}
765
766status_t Parcel::writeDupFileDescriptor(int fd)
767{
768    int dupFd = dup(fd);
769    if (dupFd < 0) {
770        return -errno;
771    }
772    status_t err = writeFileDescriptor(dupFd, true /*takeOwnership*/);
773    if (err) {
774        close(dupFd);
775    }
776    return err;
777}
778
779// WARNING: This method must stay in sync with
780// Parcelable.Creator<ParcelFileDescriptor> CREATOR
781// in frameworks/base/core/java/android/os/ParcelFileDescriptor.java
782status_t Parcel::writeParcelFileDescriptor(int fd, int commChannel) {
783    status_t status;
784
785    if (fd < 0) {
786        status = writeInt32(0); // ParcelFileDescriptor is null
787        if (status) return status;
788    } else {
789        status = writeInt32(1); // ParcelFileDescriptor is not null
790        if (status) return status;
791        status = writeDupFileDescriptor(fd);
792        if (status) return status;
793        if (commChannel < 0) {
794            status = writeInt32(0); // commChannel is null
795            if (status) return status;
796        } else {
797            status = writeInt32(1); // commChannel is not null
798            if (status) return status;
799            status = writeDupFileDescriptor(commChannel);
800        }
801    }
802    return status;
803}
804
805status_t Parcel::writeBlob(size_t len, WritableBlob* outBlob)
806{
807    status_t status;
808
809    if (!mAllowFds || len <= IN_PLACE_BLOB_LIMIT) {
810        ALOGV("writeBlob: write in place");
811        status = writeInt32(0);
812        if (status) return status;
813
814        void* ptr = writeInplace(len);
815        if (!ptr) return NO_MEMORY;
816
817        outBlob->init(false /*mapped*/, ptr, len);
818        return NO_ERROR;
819    }
820
821    ALOGV("writeBlob: write to ashmem");
822    int fd = ashmem_create_region("Parcel Blob", len);
823    if (fd < 0) return NO_MEMORY;
824
825    int result = ashmem_set_prot_region(fd, PROT_READ | PROT_WRITE);
826    if (result < 0) {
827        status = result;
828    } else {
829        void* ptr = ::mmap(NULL, len, PROT_READ | PROT_WRITE, MAP_SHARED, fd, 0);
830        if (ptr == MAP_FAILED) {
831            status = -errno;
832        } else {
833            result = ashmem_set_prot_region(fd, PROT_READ);
834            if (result < 0) {
835                status = result;
836            } else {
837                status = writeInt32(1);
838                if (!status) {
839                    status = writeFileDescriptor(fd, true /*takeOwnership*/);
840                    if (!status) {
841                        outBlob->init(true /*mapped*/, ptr, len);
842                        return NO_ERROR;
843                    }
844                }
845            }
846        }
847        ::munmap(ptr, len);
848    }
849    ::close(fd);
850    return status;
851}
852
853status_t Parcel::write(const FlattenableHelperInterface& val)
854{
855    status_t err;
856
857    // size if needed
858    const size_t len = val.getFlattenedSize();
859    const size_t fd_count = val.getFdCount();
860
861    err = this->writeInt32(len);
862    if (err) return err;
863
864    err = this->writeInt32(fd_count);
865    if (err) return err;
866
867    // payload
868    void* const buf = this->writeInplace(PAD_SIZE(len));
869    if (buf == NULL)
870        return BAD_VALUE;
871
872    int* fds = NULL;
873    if (fd_count) {
874        fds = new int[fd_count];
875    }
876
877    err = val.flatten(buf, len, fds, fd_count);
878    for (size_t i=0 ; i<fd_count && err==NO_ERROR ; i++) {
879        err = this->writeDupFileDescriptor( fds[i] );
880    }
881
882    if (fd_count) {
883        delete [] fds;
884    }
885
886    return err;
887}
888
889status_t Parcel::writeObject(const flat_binder_object& val, bool nullMetaData)
890{
891    const bool enoughData = (mDataPos+sizeof(val)) <= mDataCapacity;
892    const bool enoughObjects = mObjectsSize < mObjectsCapacity;
893    if (enoughData && enoughObjects) {
894restart_write:
895        *reinterpret_cast<flat_binder_object*>(mData+mDataPos) = val;
896
897        // Need to write meta-data?
898        if (nullMetaData || val.binder != 0) {
899            mObjects[mObjectsSize] = mDataPos;
900            acquire_object(ProcessState::self(), val, this);
901            mObjectsSize++;
902        }
903
904        // remember if it's a file descriptor
905        if (val.type == BINDER_TYPE_FD) {
906            if (!mAllowFds) {
907                return FDS_NOT_ALLOWED;
908            }
909            mHasFds = mFdsKnown = true;
910        }
911
912        return finishWrite(sizeof(flat_binder_object));
913    }
914
915    if (!enoughData) {
916        const status_t err = growData(sizeof(val));
917        if (err != NO_ERROR) return err;
918    }
919    if (!enoughObjects) {
920        size_t newSize = ((mObjectsSize+2)*3)/2;
921        binder_size_t* objects = (binder_size_t*)realloc(mObjects, newSize*sizeof(binder_size_t));
922        if (objects == NULL) return NO_MEMORY;
923        mObjects = objects;
924        mObjectsCapacity = newSize;
925    }
926
927    goto restart_write;
928}
929
930status_t Parcel::writeNoException()
931{
932    return writeInt32(0);
933}
934
935void Parcel::remove(size_t /*start*/, size_t /*amt*/)
936{
937    LOG_ALWAYS_FATAL("Parcel::remove() not yet implemented!");
938}
939
940status_t Parcel::read(void* outData, size_t len) const
941{
942    if ((mDataPos+PAD_SIZE(len)) >= mDataPos && (mDataPos+PAD_SIZE(len)) <= mDataSize
943            && len <= PAD_SIZE(len)) {
944        memcpy(outData, mData+mDataPos, len);
945        mDataPos += PAD_SIZE(len);
946        ALOGV("read Setting data pos of %p to %zu", this, mDataPos);
947        return NO_ERROR;
948    }
949    return NOT_ENOUGH_DATA;
950}
951
952const void* Parcel::readInplace(size_t len) const
953{
954    if ((mDataPos+PAD_SIZE(len)) >= mDataPos && (mDataPos+PAD_SIZE(len)) <= mDataSize
955            && len <= PAD_SIZE(len)) {
956        const void* data = mData+mDataPos;
957        mDataPos += PAD_SIZE(len);
958        ALOGV("readInplace Setting data pos of %p to %zu", this, mDataPos);
959        return data;
960    }
961    return NULL;
962}
963
964template<class T>
965status_t Parcel::readAligned(T *pArg) const {
966    COMPILE_TIME_ASSERT_FUNCTION_SCOPE(PAD_SIZE(sizeof(T)) == sizeof(T));
967
968    if ((mDataPos+sizeof(T)) <= mDataSize) {
969        const void* data = mData+mDataPos;
970        mDataPos += sizeof(T);
971        *pArg =  *reinterpret_cast<const T*>(data);
972        return NO_ERROR;
973    } else {
974        return NOT_ENOUGH_DATA;
975    }
976}
977
978template<class T>
979T Parcel::readAligned() const {
980    T result;
981    if (readAligned(&result) != NO_ERROR) {
982        result = 0;
983    }
984
985    return result;
986}
987
988template<class T>
989status_t Parcel::writeAligned(T val) {
990    COMPILE_TIME_ASSERT_FUNCTION_SCOPE(PAD_SIZE(sizeof(T)) == sizeof(T));
991
992    if ((mDataPos+sizeof(val)) <= mDataCapacity) {
993restart_write:
994        *reinterpret_cast<T*>(mData+mDataPos) = val;
995        return finishWrite(sizeof(val));
996    }
997
998    status_t err = growData(sizeof(val));
999    if (err == NO_ERROR) goto restart_write;
1000    return err;
1001}
1002
1003status_t Parcel::readInt32(int32_t *pArg) const
1004{
1005    return readAligned(pArg);
1006}
1007
1008int32_t Parcel::readInt32() const
1009{
1010    return readAligned<int32_t>();
1011}
1012
1013
1014status_t Parcel::readInt64(int64_t *pArg) const
1015{
1016    return readAligned(pArg);
1017}
1018
1019
1020int64_t Parcel::readInt64() const
1021{
1022    return readAligned<int64_t>();
1023}
1024
1025status_t Parcel::readPointer(uintptr_t *pArg) const
1026{
1027    status_t ret;
1028    binder_uintptr_t ptr;
1029    ret = readAligned(&ptr);
1030    if (!ret)
1031        *pArg = ptr;
1032    return ret;
1033}
1034
1035uintptr_t Parcel::readPointer() const
1036{
1037    return readAligned<binder_uintptr_t>();
1038}
1039
1040
1041status_t Parcel::readFloat(float *pArg) const
1042{
1043    return readAligned(pArg);
1044}
1045
1046
1047float Parcel::readFloat() const
1048{
1049    return readAligned<float>();
1050}
1051
1052#if defined(__mips__) && defined(__mips_hard_float)
1053
1054status_t Parcel::readDouble(double *pArg) const
1055{
1056    union {
1057      double d;
1058      unsigned long long ll;
1059    } u;
1060    u.d = 0;
1061    status_t status;
1062    status = readAligned(&u.ll);
1063    *pArg = u.d;
1064    return status;
1065}
1066
1067double Parcel::readDouble() const
1068{
1069    union {
1070      double d;
1071      unsigned long long ll;
1072    } u;
1073    u.ll = readAligned<unsigned long long>();
1074    return u.d;
1075}
1076
1077#else
1078
1079status_t Parcel::readDouble(double *pArg) const
1080{
1081    return readAligned(pArg);
1082}
1083
1084double Parcel::readDouble() const
1085{
1086    return readAligned<double>();
1087}
1088
1089#endif
1090
1091status_t Parcel::readIntPtr(intptr_t *pArg) const
1092{
1093    return readAligned(pArg);
1094}
1095
1096
1097intptr_t Parcel::readIntPtr() const
1098{
1099    return readAligned<intptr_t>();
1100}
1101
1102
1103const char* Parcel::readCString() const
1104{
1105    const size_t avail = mDataSize-mDataPos;
1106    if (avail > 0) {
1107        const char* str = reinterpret_cast<const char*>(mData+mDataPos);
1108        // is the string's trailing NUL within the parcel's valid bounds?
1109        const char* eos = reinterpret_cast<const char*>(memchr(str, 0, avail));
1110        if (eos) {
1111            const size_t len = eos - str;
1112            mDataPos += PAD_SIZE(len+1);
1113            ALOGV("readCString Setting data pos of %p to %zu", this, mDataPos);
1114            return str;
1115        }
1116    }
1117    return NULL;
1118}
1119
1120String8 Parcel::readString8() const
1121{
1122    int32_t size = readInt32();
1123    // watch for potential int overflow adding 1 for trailing NUL
1124    if (size > 0 && size < INT32_MAX) {
1125        const char* str = (const char*)readInplace(size+1);
1126        if (str) return String8(str, size);
1127    }
1128    return String8();
1129}
1130
1131String16 Parcel::readString16() const
1132{
1133    size_t len;
1134    const char16_t* str = readString16Inplace(&len);
1135    if (str) return String16(str, len);
1136    ALOGE("Reading a NULL string not supported here.");
1137    return String16();
1138}
1139
1140const char16_t* Parcel::readString16Inplace(size_t* outLen) const
1141{
1142    int32_t size = readInt32();
1143    // watch for potential int overflow from size+1
1144    if (size >= 0 && size < INT32_MAX) {
1145        *outLen = size;
1146        const char16_t* str = (const char16_t*)readInplace((size+1)*sizeof(char16_t));
1147        if (str != NULL) {
1148            return str;
1149        }
1150    }
1151    *outLen = 0;
1152    return NULL;
1153}
1154
1155sp<IBinder> Parcel::readStrongBinder() const
1156{
1157    sp<IBinder> val;
1158    unflatten_binder(ProcessState::self(), *this, &val);
1159    return val;
1160}
1161
1162wp<IBinder> Parcel::readWeakBinder() const
1163{
1164    wp<IBinder> val;
1165    unflatten_binder(ProcessState::self(), *this, &val);
1166    return val;
1167}
1168
1169int32_t Parcel::readExceptionCode() const
1170{
1171  int32_t exception_code = readAligned<int32_t>();
1172  if (exception_code == EX_HAS_REPLY_HEADER) {
1173    int32_t header_start = dataPosition();
1174    int32_t header_size = readAligned<int32_t>();
1175    // Skip over fat responses headers.  Not used (or propagated) in
1176    // native code
1177    setDataPosition(header_start + header_size);
1178    // And fat response headers are currently only used when there are no
1179    // exceptions, so return no error:
1180    return 0;
1181  }
1182  return exception_code;
1183}
1184
1185native_handle* Parcel::readNativeHandle() const
1186{
1187    int numFds, numInts;
1188    status_t err;
1189    err = readInt32(&numFds);
1190    if (err != NO_ERROR) return 0;
1191    err = readInt32(&numInts);
1192    if (err != NO_ERROR) return 0;
1193
1194    native_handle* h = native_handle_create(numFds, numInts);
1195    for (int i=0 ; err==NO_ERROR && i<numFds ; i++) {
1196        h->data[i] = dup(readFileDescriptor());
1197        if (h->data[i] < 0) err = BAD_VALUE;
1198    }
1199    err = read(h->data + numFds, sizeof(int)*numInts);
1200    if (err != NO_ERROR) {
1201        native_handle_close(h);
1202        native_handle_delete(h);
1203        h = 0;
1204    }
1205    return h;
1206}
1207
1208
1209int Parcel::readFileDescriptor() const
1210{
1211    const flat_binder_object* flat = readObject(true);
1212    if (flat) {
1213        switch (flat->type) {
1214            case BINDER_TYPE_FD:
1215                //ALOGI("Returning file descriptor %ld from parcel %p", flat->handle, this);
1216                return flat->handle;
1217        }
1218    }
1219    return BAD_TYPE;
1220}
1221
1222// WARNING: This method must stay in sync with writeToParcel()
1223// in frameworks/base/core/java/android/os/ParcelFileDescriptor.java
1224int Parcel::readParcelFileDescriptor(int& outCommChannel) const {
1225    int fd;
1226    outCommChannel = -1;
1227
1228    if (readInt32() == 0) {
1229        fd = -1;
1230    } else {
1231        fd = readFileDescriptor();
1232        if (fd >= 0 && readInt32() != 0) {
1233            outCommChannel = readFileDescriptor();
1234        }
1235    }
1236    return fd;
1237}
1238
1239status_t Parcel::readBlob(size_t len, ReadableBlob* outBlob) const
1240{
1241    int32_t useAshmem;
1242    status_t status = readInt32(&useAshmem);
1243    if (status) return status;
1244
1245    if (!useAshmem) {
1246        ALOGV("readBlob: read in place");
1247        const void* ptr = readInplace(len);
1248        if (!ptr) return BAD_VALUE;
1249
1250        outBlob->init(false /*mapped*/, const_cast<void*>(ptr), len);
1251        return NO_ERROR;
1252    }
1253
1254    ALOGV("readBlob: read from ashmem");
1255    int fd = readFileDescriptor();
1256    if (fd == int(BAD_TYPE)) return BAD_VALUE;
1257
1258    void* ptr = ::mmap(NULL, len, PROT_READ, MAP_SHARED, fd, 0);
1259    if (ptr == MAP_FAILED) return NO_MEMORY;
1260
1261    outBlob->init(true /*mapped*/, ptr, len);
1262    return NO_ERROR;
1263}
1264
1265status_t Parcel::read(FlattenableHelperInterface& val) const
1266{
1267    // size
1268    const size_t len = this->readInt32();
1269    const size_t fd_count = this->readInt32();
1270
1271    // payload
1272    void const* const buf = this->readInplace(PAD_SIZE(len));
1273    if (buf == NULL)
1274        return BAD_VALUE;
1275
1276    int* fds = NULL;
1277    if (fd_count) {
1278        fds = new int[fd_count];
1279    }
1280
1281    status_t err = NO_ERROR;
1282    for (size_t i=0 ; i<fd_count && err==NO_ERROR ; i++) {
1283        fds[i] = dup(this->readFileDescriptor());
1284        if (fds[i] < 0) {
1285            err = BAD_VALUE;
1286            ALOGE("dup() failed in Parcel::read, i is %zu, fds[i] is %d, fd_count is %zu, error: %s",
1287                i, fds[i], fd_count, strerror(errno));
1288        }
1289    }
1290
1291    if (err == NO_ERROR) {
1292        err = val.unflatten(buf, len, fds, fd_count);
1293    }
1294
1295    if (fd_count) {
1296        delete [] fds;
1297    }
1298
1299    return err;
1300}
1301const flat_binder_object* Parcel::readObject(bool nullMetaData) const
1302{
1303    const size_t DPOS = mDataPos;
1304    if ((DPOS+sizeof(flat_binder_object)) <= mDataSize) {
1305        const flat_binder_object* obj
1306                = reinterpret_cast<const flat_binder_object*>(mData+DPOS);
1307        mDataPos = DPOS + sizeof(flat_binder_object);
1308        if (!nullMetaData && (obj->cookie == 0 && obj->binder == 0)) {
1309            // When transferring a NULL object, we don't write it into
1310            // the object list, so we don't want to check for it when
1311            // reading.
1312            ALOGV("readObject Setting data pos of %p to %zu", this, mDataPos);
1313            return obj;
1314        }
1315
1316        // Ensure that this object is valid...
1317        binder_size_t* const OBJS = mObjects;
1318        const size_t N = mObjectsSize;
1319        size_t opos = mNextObjectHint;
1320
1321        if (N > 0) {
1322            ALOGV("Parcel %p looking for obj at %zu, hint=%zu",
1323                 this, DPOS, opos);
1324
1325            // Start at the current hint position, looking for an object at
1326            // the current data position.
1327            if (opos < N) {
1328                while (opos < (N-1) && OBJS[opos] < DPOS) {
1329                    opos++;
1330                }
1331            } else {
1332                opos = N-1;
1333            }
1334            if (OBJS[opos] == DPOS) {
1335                // Found it!
1336                ALOGV("Parcel %p found obj %zu at index %zu with forward search",
1337                     this, DPOS, opos);
1338                mNextObjectHint = opos+1;
1339                ALOGV("readObject Setting data pos of %p to %zu", this, mDataPos);
1340                return obj;
1341            }
1342
1343            // Look backwards for it...
1344            while (opos > 0 && OBJS[opos] > DPOS) {
1345                opos--;
1346            }
1347            if (OBJS[opos] == DPOS) {
1348                // Found it!
1349                ALOGV("Parcel %p found obj %zu at index %zu with backward search",
1350                     this, DPOS, opos);
1351                mNextObjectHint = opos+1;
1352                ALOGV("readObject Setting data pos of %p to %zu", this, mDataPos);
1353                return obj;
1354            }
1355        }
1356        ALOGW("Attempt to read object from Parcel %p at offset %zu that is not in the object list",
1357             this, DPOS);
1358    }
1359    return NULL;
1360}
1361
1362void Parcel::closeFileDescriptors()
1363{
1364    size_t i = mObjectsSize;
1365    if (i > 0) {
1366        //ALOGI("Closing file descriptors for %zu objects...", i);
1367    }
1368    while (i > 0) {
1369        i--;
1370        const flat_binder_object* flat
1371            = reinterpret_cast<flat_binder_object*>(mData+mObjects[i]);
1372        if (flat->type == BINDER_TYPE_FD) {
1373            //ALOGI("Closing fd: %ld", flat->handle);
1374            close(flat->handle);
1375        }
1376    }
1377}
1378
1379uintptr_t Parcel::ipcData() const
1380{
1381    return reinterpret_cast<uintptr_t>(mData);
1382}
1383
1384size_t Parcel::ipcDataSize() const
1385{
1386    return (mDataSize > mDataPos ? mDataSize : mDataPos);
1387}
1388
1389uintptr_t Parcel::ipcObjects() const
1390{
1391    return reinterpret_cast<uintptr_t>(mObjects);
1392}
1393
1394size_t Parcel::ipcObjectsCount() const
1395{
1396    return mObjectsSize;
1397}
1398
1399void Parcel::ipcSetDataReference(const uint8_t* data, size_t dataSize,
1400    const binder_size_t* objects, size_t objectsCount, release_func relFunc, void* relCookie)
1401{
1402    binder_size_t minOffset = 0;
1403    freeDataNoInit();
1404    mError = NO_ERROR;
1405    mData = const_cast<uint8_t*>(data);
1406    mDataSize = mDataCapacity = dataSize;
1407    //ALOGI("setDataReference Setting data size of %p to %lu (pid=%d)", this, mDataSize, getpid());
1408    mDataPos = 0;
1409    ALOGV("setDataReference Setting data pos of %p to %zu", this, mDataPos);
1410    mObjects = const_cast<binder_size_t*>(objects);
1411    mObjectsSize = mObjectsCapacity = objectsCount;
1412    mNextObjectHint = 0;
1413    mOwner = relFunc;
1414    mOwnerCookie = relCookie;
1415    for (size_t i = 0; i < mObjectsSize; i++) {
1416        binder_size_t offset = mObjects[i];
1417        if (offset < minOffset) {
1418            ALOGE("%s: bad object offset %"PRIu64" < %"PRIu64"\n",
1419                  __func__, (uint64_t)offset, (uint64_t)minOffset);
1420            mObjectsSize = 0;
1421            break;
1422        }
1423        minOffset = offset + sizeof(flat_binder_object);
1424    }
1425    scanForFds();
1426}
1427
1428void Parcel::print(TextOutput& to, uint32_t /*flags*/) const
1429{
1430    to << "Parcel(";
1431
1432    if (errorCheck() != NO_ERROR) {
1433        const status_t err = errorCheck();
1434        to << "Error: " << (void*)(intptr_t)err << " \"" << strerror(-err) << "\"";
1435    } else if (dataSize() > 0) {
1436        const uint8_t* DATA = data();
1437        to << indent << HexDump(DATA, dataSize()) << dedent;
1438        const binder_size_t* OBJS = objects();
1439        const size_t N = objectsCount();
1440        for (size_t i=0; i<N; i++) {
1441            const flat_binder_object* flat
1442                = reinterpret_cast<const flat_binder_object*>(DATA+OBJS[i]);
1443            to << endl << "Object #" << i << " @ " << (void*)OBJS[i] << ": "
1444                << TypeCode(flat->type & 0x7f7f7f00)
1445                << " = " << flat->binder;
1446        }
1447    } else {
1448        to << "NULL";
1449    }
1450
1451    to << ")";
1452}
1453
1454void Parcel::releaseObjects()
1455{
1456    const sp<ProcessState> proc(ProcessState::self());
1457    size_t i = mObjectsSize;
1458    uint8_t* const data = mData;
1459    binder_size_t* const objects = mObjects;
1460    while (i > 0) {
1461        i--;
1462        const flat_binder_object* flat
1463            = reinterpret_cast<flat_binder_object*>(data+objects[i]);
1464        release_object(proc, *flat, this);
1465    }
1466}
1467
1468void Parcel::acquireObjects()
1469{
1470    const sp<ProcessState> proc(ProcessState::self());
1471    size_t i = mObjectsSize;
1472    uint8_t* const data = mData;
1473    binder_size_t* const objects = mObjects;
1474    while (i > 0) {
1475        i--;
1476        const flat_binder_object* flat
1477            = reinterpret_cast<flat_binder_object*>(data+objects[i]);
1478        acquire_object(proc, *flat, this);
1479    }
1480}
1481
1482void Parcel::freeData()
1483{
1484    freeDataNoInit();
1485    initState();
1486}
1487
1488void Parcel::freeDataNoInit()
1489{
1490    if (mOwner) {
1491        //ALOGI("Freeing data ref of %p (pid=%d)", this, getpid());
1492        mOwner(this, mData, mDataSize, mObjects, mObjectsSize, mOwnerCookie);
1493    } else {
1494        releaseObjects();
1495        if (mData) free(mData);
1496        if (mObjects) free(mObjects);
1497    }
1498}
1499
1500status_t Parcel::growData(size_t len)
1501{
1502    size_t newSize = ((mDataSize+len)*3)/2;
1503    return (newSize <= mDataSize)
1504            ? (status_t) NO_MEMORY
1505            : continueWrite(newSize);
1506}
1507
1508status_t Parcel::restartWrite(size_t desired)
1509{
1510    if (mOwner) {
1511        freeData();
1512        return continueWrite(desired);
1513    }
1514
1515    uint8_t* data = (uint8_t*)realloc(mData, desired);
1516    if (!data && desired > mDataCapacity) {
1517        mError = NO_MEMORY;
1518        return NO_MEMORY;
1519    }
1520
1521    releaseObjects();
1522
1523    if (data) {
1524        mData = data;
1525        mDataCapacity = desired;
1526    }
1527
1528    mDataSize = mDataPos = 0;
1529    ALOGV("restartWrite Setting data size of %p to %zu", this, mDataSize);
1530    ALOGV("restartWrite Setting data pos of %p to %zu", this, mDataPos);
1531
1532    free(mObjects);
1533    mObjects = NULL;
1534    mObjectsSize = mObjectsCapacity = 0;
1535    mNextObjectHint = 0;
1536    mHasFds = false;
1537    mFdsKnown = true;
1538    mAllowFds = true;
1539
1540    return NO_ERROR;
1541}
1542
1543status_t Parcel::continueWrite(size_t desired)
1544{
1545    // If shrinking, first adjust for any objects that appear
1546    // after the new data size.
1547    size_t objectsSize = mObjectsSize;
1548    if (desired < mDataSize) {
1549        if (desired == 0) {
1550            objectsSize = 0;
1551        } else {
1552            while (objectsSize > 0) {
1553                if (mObjects[objectsSize-1] < desired)
1554                    break;
1555                objectsSize--;
1556            }
1557        }
1558    }
1559
1560    if (mOwner) {
1561        // If the size is going to zero, just release the owner's data.
1562        if (desired == 0) {
1563            freeData();
1564            return NO_ERROR;
1565        }
1566
1567        // If there is a different owner, we need to take
1568        // posession.
1569        uint8_t* data = (uint8_t*)malloc(desired);
1570        if (!data) {
1571            mError = NO_MEMORY;
1572            return NO_MEMORY;
1573        }
1574        binder_size_t* objects = NULL;
1575
1576        if (objectsSize) {
1577            objects = (binder_size_t*)malloc(objectsSize*sizeof(binder_size_t));
1578            if (!objects) {
1579                free(data);
1580
1581                mError = NO_MEMORY;
1582                return NO_MEMORY;
1583            }
1584
1585            // Little hack to only acquire references on objects
1586            // we will be keeping.
1587            size_t oldObjectsSize = mObjectsSize;
1588            mObjectsSize = objectsSize;
1589            acquireObjects();
1590            mObjectsSize = oldObjectsSize;
1591        }
1592
1593        if (mData) {
1594            memcpy(data, mData, mDataSize < desired ? mDataSize : desired);
1595        }
1596        if (objects && mObjects) {
1597            memcpy(objects, mObjects, objectsSize*sizeof(binder_size_t));
1598        }
1599        //ALOGI("Freeing data ref of %p (pid=%d)", this, getpid());
1600        mOwner(this, mData, mDataSize, mObjects, mObjectsSize, mOwnerCookie);
1601        mOwner = NULL;
1602
1603        mData = data;
1604        mObjects = objects;
1605        mDataSize = (mDataSize < desired) ? mDataSize : desired;
1606        ALOGV("continueWrite Setting data size of %p to %zu", this, mDataSize);
1607        mDataCapacity = desired;
1608        mObjectsSize = mObjectsCapacity = objectsSize;
1609        mNextObjectHint = 0;
1610
1611    } else if (mData) {
1612        if (objectsSize < mObjectsSize) {
1613            // Need to release refs on any objects we are dropping.
1614            const sp<ProcessState> proc(ProcessState::self());
1615            for (size_t i=objectsSize; i<mObjectsSize; i++) {
1616                const flat_binder_object* flat
1617                    = reinterpret_cast<flat_binder_object*>(mData+mObjects[i]);
1618                if (flat->type == BINDER_TYPE_FD) {
1619                    // will need to rescan because we may have lopped off the only FDs
1620                    mFdsKnown = false;
1621                }
1622                release_object(proc, *flat, this);
1623            }
1624            binder_size_t* objects =
1625                (binder_size_t*)realloc(mObjects, objectsSize*sizeof(binder_size_t));
1626            if (objects) {
1627                mObjects = objects;
1628            }
1629            mObjectsSize = objectsSize;
1630            mNextObjectHint = 0;
1631        }
1632
1633        // We own the data, so we can just do a realloc().
1634        if (desired > mDataCapacity) {
1635            uint8_t* data = (uint8_t*)realloc(mData, desired);
1636            if (data) {
1637                mData = data;
1638                mDataCapacity = desired;
1639            } else if (desired > mDataCapacity) {
1640                mError = NO_MEMORY;
1641                return NO_MEMORY;
1642            }
1643        } else {
1644            if (mDataSize > desired) {
1645                mDataSize = desired;
1646                ALOGV("continueWrite Setting data size of %p to %zu", this, mDataSize);
1647            }
1648            if (mDataPos > desired) {
1649                mDataPos = desired;
1650                ALOGV("continueWrite Setting data pos of %p to %zu", this, mDataPos);
1651            }
1652        }
1653
1654    } else {
1655        // This is the first data.  Easy!
1656        uint8_t* data = (uint8_t*)malloc(desired);
1657        if (!data) {
1658            mError = NO_MEMORY;
1659            return NO_MEMORY;
1660        }
1661
1662        if(!(mDataCapacity == 0 && mObjects == NULL
1663             && mObjectsCapacity == 0)) {
1664            ALOGE("continueWrite: %zu/%p/%zu/%zu", mDataCapacity, mObjects, mObjectsCapacity, desired);
1665        }
1666
1667        mData = data;
1668        mDataSize = mDataPos = 0;
1669        ALOGV("continueWrite Setting data size of %p to %zu", this, mDataSize);
1670        ALOGV("continueWrite Setting data pos of %p to %zu", this, mDataPos);
1671        mDataCapacity = desired;
1672    }
1673
1674    return NO_ERROR;
1675}
1676
1677void Parcel::initState()
1678{
1679    mError = NO_ERROR;
1680    mData = 0;
1681    mDataSize = 0;
1682    mDataCapacity = 0;
1683    mDataPos = 0;
1684    ALOGV("initState Setting data size of %p to %zu", this, mDataSize);
1685    ALOGV("initState Setting data pos of %p to %zu", this, mDataPos);
1686    mObjects = NULL;
1687    mObjectsSize = 0;
1688    mObjectsCapacity = 0;
1689    mNextObjectHint = 0;
1690    mHasFds = false;
1691    mFdsKnown = true;
1692    mAllowFds = true;
1693    mOwner = NULL;
1694}
1695
1696void Parcel::scanForFds() const
1697{
1698    bool hasFds = false;
1699    for (size_t i=0; i<mObjectsSize; i++) {
1700        const flat_binder_object* flat
1701            = reinterpret_cast<const flat_binder_object*>(mData + mObjects[i]);
1702        if (flat->type == BINDER_TYPE_FD) {
1703            hasFds = true;
1704            break;
1705        }
1706    }
1707    mHasFds = hasFds;
1708    mFdsKnown = true;
1709}
1710
1711// --- Parcel::Blob ---
1712
1713Parcel::Blob::Blob() :
1714        mMapped(false), mData(NULL), mSize(0) {
1715}
1716
1717Parcel::Blob::~Blob() {
1718    release();
1719}
1720
1721void Parcel::Blob::release() {
1722    if (mMapped && mData) {
1723        ::munmap(mData, mSize);
1724    }
1725    clear();
1726}
1727
1728void Parcel::Blob::init(bool mapped, void* data, size_t size) {
1729    mMapped = mapped;
1730    mData = data;
1731    mSize = size;
1732}
1733
1734void Parcel::Blob::clear() {
1735    mMapped = false;
1736    mData = NULL;
1737    mSize = 0;
1738}
1739
1740}; // namespace android
1741