replicant-frameworks_native/include/binder/Parcel.h

439 lines
16 KiB
C++

/*
* Copyright (C) 2005 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#ifndef ANDROID_PARCEL_H
#define ANDROID_PARCEL_H
#include <cutils/native_handle.h>
#include <utils/Errors.h>
#include <utils/RefBase.h>
#include <utils/String16.h>
#include <utils/Vector.h>
#include <utils/Flattenable.h>
#include <linux/binder.h>
// ---------------------------------------------------------------------------
namespace android {
template <typename T> class Flattenable;
template <typename T> class LightFlattenable;
class IBinder;
class IPCThreadState;
class ProcessState;
class String8;
class TextOutput;
class Parcel {
friend class IPCThreadState;
public:
class ReadableBlob;
class WritableBlob;
Parcel();
~Parcel();
const uint8_t* data() const;
size_t dataSize() const;
size_t dataAvail() const;
size_t dataPosition() const;
size_t dataCapacity() const;
status_t setDataSize(size_t size);
void setDataPosition(size_t pos) const;
status_t setDataCapacity(size_t size);
status_t setData(const uint8_t* buffer, size_t len);
status_t appendFrom(const Parcel *parcel,
size_t start, size_t len);
bool allowFds() const;
bool pushAllowFds(bool allowFds);
void restoreAllowFds(bool lastValue);
bool hasFileDescriptors() const;
// Writes the RPC header.
status_t writeInterfaceToken(const String16& interface);
// Parses the RPC header, returning true if the interface name
// in the header matches the expected interface from the caller.
//
// Additionally, enforceInterface does part of the work of
// propagating the StrictMode policy mask, populating the current
// IPCThreadState, which as an optimization may optionally be
// passed in.
bool enforceInterface(const String16& interface,
IPCThreadState* threadState = NULL) const;
bool checkInterface(IBinder*) const;
void freeData();
private:
const binder_size_t* objects() const;
public:
size_t objectsCount() const;
status_t errorCheck() const;
void setError(status_t err);
status_t write(const void* data, size_t len);
void* writeInplace(size_t len);
status_t writeUnpadded(const void* data, size_t len);
status_t writeInt32(int32_t val);
status_t writeUint32(uint32_t val);
status_t writeInt64(int64_t val);
status_t writeUint64(uint64_t val);
status_t writeFloat(float val);
status_t writeDouble(double val);
status_t writeCString(const char* str);
status_t writeString8(const String8& str);
status_t writeString16(const String16& str);
status_t writeString16(const char16_t* str, size_t len);
status_t writeStrongBinder(const sp<IBinder>& val);
status_t writeWeakBinder(const wp<IBinder>& val);
status_t writeInt32Array(size_t len, const int32_t *val);
status_t writeByteArray(size_t len, const uint8_t *val);
template<typename T>
status_t write(const Flattenable<T>& val);
template<typename T>
status_t write(const LightFlattenable<T>& val);
// Place a native_handle into the parcel (the native_handle's file-
// descriptors are dup'ed, so it is safe to delete the native_handle
// when this function returns).
// Doesn't take ownership of the native_handle.
status_t writeNativeHandle(const native_handle* handle);
// Place a file descriptor into the parcel. The given fd must remain
// valid for the lifetime of the parcel.
// The Parcel does not take ownership of the given fd unless you ask it to.
status_t writeFileDescriptor(int fd, bool takeOwnership = false);
// Place a file descriptor into the parcel. A dup of the fd is made, which
// will be closed once the parcel is destroyed.
status_t writeDupFileDescriptor(int fd);
// Writes a blob to the parcel.
// If the blob is small, then it is stored in-place, otherwise it is
// transferred by way of an anonymous shared memory region. Prefer sending
// immutable blobs if possible since they may be subsequently transferred between
// processes without further copying whereas mutable blobs always need to be copied.
// The caller should call release() on the blob after writing its contents.
status_t writeBlob(size_t len, bool mutableCopy, WritableBlob* outBlob);
// Write an existing immutable blob file descriptor to the parcel.
// This allows the client to send the same blob to multiple processes
// as long as it keeps a dup of the blob file descriptor handy for later.
status_t writeDupImmutableBlobFileDescriptor(int fd);
status_t writeObject(const flat_binder_object& val, bool nullMetaData);
// Like Parcel.java's writeNoException(). Just writes a zero int32.
// Currently the native implementation doesn't do any of the StrictMode
// stack gathering and serialization that the Java implementation does.
status_t writeNoException();
void remove(size_t start, size_t amt);
status_t read(void* outData, size_t len) const;
const void* readInplace(size_t len) const;
int32_t readInt32() const;
status_t readInt32(int32_t *pArg) const;
uint32_t readUint32() const;
status_t readUint32(uint32_t *pArg) const;
int64_t readInt64() const;
status_t readInt64(int64_t *pArg) const;
uint64_t readUint64() const;
status_t readUint64(uint64_t *pArg) const;
float readFloat() const;
status_t readFloat(float *pArg) const;
double readDouble() const;
status_t readDouble(double *pArg) const;
intptr_t readIntPtr() const;
status_t readIntPtr(intptr_t *pArg) const;
const char* readCString() const;
String8 readString8() const;
String16 readString16() const;
const char16_t* readString16Inplace(size_t* outLen) const;
sp<IBinder> readStrongBinder() const;
wp<IBinder> readWeakBinder() const;
template<typename T>
status_t read(Flattenable<T>& val) const;
template<typename T>
status_t read(LightFlattenable<T>& val) const;
// Like Parcel.java's readExceptionCode(). Reads the first int32
// off of a Parcel's header, returning 0 or the negative error
// code on exceptions, but also deals with skipping over rich
// response headers. Callers should use this to read & parse the
// response headers rather than doing it by hand.
int32_t readExceptionCode() const;
// Retrieve native_handle from the parcel. This returns a copy of the
// parcel's native_handle (the caller takes ownership). The caller
// must free the native_handle with native_handle_close() and
// native_handle_delete().
native_handle* readNativeHandle() const;
// Retrieve a file descriptor from the parcel. This returns the raw fd
// in the parcel, which you do not own -- use dup() to get your own copy.
int readFileDescriptor() const;
// Reads a blob from the parcel.
// The caller should call release() on the blob after reading its contents.
status_t readBlob(size_t len, ReadableBlob* outBlob) const;
const flat_binder_object* readObject(bool nullMetaData) const;
// Explicitly close all file descriptors in the parcel.
void closeFileDescriptors();
// Debugging: get metrics on current allocations.
static size_t getGlobalAllocSize();
static size_t getGlobalAllocCount();
private:
typedef void (*release_func)(Parcel* parcel,
const uint8_t* data, size_t dataSize,
const binder_size_t* objects, size_t objectsSize,
void* cookie);
uintptr_t ipcData() const;
size_t ipcDataSize() const;
uintptr_t ipcObjects() const;
size_t ipcObjectsCount() const;
void ipcSetDataReference(const uint8_t* data, size_t dataSize,
const binder_size_t* objects, size_t objectsCount,
release_func relFunc, void* relCookie);
public:
void print(TextOutput& to, uint32_t flags = 0) const;
private:
Parcel(const Parcel& o);
Parcel& operator=(const Parcel& o);
status_t finishWrite(size_t len);
void releaseObjects();
void acquireObjects();
status_t growData(size_t len);
status_t restartWrite(size_t desired);
status_t continueWrite(size_t desired);
status_t writePointer(uintptr_t val);
status_t readPointer(uintptr_t *pArg) const;
uintptr_t readPointer() const;
void freeDataNoInit();
void initState();
void scanForFds() const;
status_t validateReadData(size_t len) const;
template<class T>
status_t readAligned(T *pArg) const;
template<class T> T readAligned() const;
template<class T>
status_t writeAligned(T val);
status_t mError;
uint8_t* mData;
size_t mDataSize;
size_t mDataCapacity;
mutable size_t mDataPos;
binder_size_t* mObjects;
size_t mObjectsSize;
size_t mObjectsCapacity;
mutable size_t mNextObjectHint;
mutable bool mObjectsSorted;
mutable bool mFdsKnown;
mutable bool mHasFds;
bool mAllowFds;
release_func mOwner;
void* mOwnerCookie;
class Blob {
public:
Blob();
~Blob();
void clear();
void release();
inline size_t size() const { return mSize; }
inline int fd() const { return mFd; };
inline bool isMutable() const { return mMutable; }
protected:
void init(int fd, void* data, size_t size, bool isMutable);
int mFd; // owned by parcel so not closed when released
void* mData;
size_t mSize;
bool mMutable;
};
class FlattenableHelperInterface {
protected:
~FlattenableHelperInterface() { }
public:
virtual size_t getFlattenedSize() const = 0;
virtual size_t getFdCount() const = 0;
virtual status_t flatten(void* buffer, size_t size, int* fds, size_t count) const = 0;
virtual status_t unflatten(void const* buffer, size_t size, int const* fds, size_t count) = 0;
};
template<typename T>
class FlattenableHelper : public FlattenableHelperInterface {
friend class Parcel;
const Flattenable<T>& val;
explicit FlattenableHelper(const Flattenable<T>& val) : val(val) { }
public:
virtual size_t getFlattenedSize() const {
return val.getFlattenedSize();
}
virtual size_t getFdCount() const {
return val.getFdCount();
}
virtual status_t flatten(void* buffer, size_t size, int* fds, size_t count) const {
return val.flatten(buffer, size, fds, count);
}
virtual status_t unflatten(void const* buffer, size_t size, int const* fds, size_t count) {
return const_cast<Flattenable<T>&>(val).unflatten(buffer, size, fds, count);
}
};
status_t write(const FlattenableHelperInterface& val);
status_t read(FlattenableHelperInterface& val) const;
public:
class ReadableBlob : public Blob {
friend class Parcel;
public:
inline const void* data() const { return mData; }
inline void* mutableData() { return isMutable() ? mData : NULL; }
};
class WritableBlob : public Blob {
friend class Parcel;
public:
inline void* data() { return mData; }
};
#ifndef DISABLE_ASHMEM_TRACKING
private:
size_t mOpenAshmemSize;
#endif
public:
// TODO: Remove once ABI can be changed.
size_t getBlobAshmemSize() const;
size_t getOpenAshmemSize() const;
};
// ---------------------------------------------------------------------------
template<typename T>
status_t Parcel::write(const Flattenable<T>& val) {
const FlattenableHelper<T> helper(val);
return write(helper);
}
template<typename T>
status_t Parcel::write(const LightFlattenable<T>& val) {
size_t size(val.getFlattenedSize());
if (!val.isFixedSize()) {
status_t err = writeInt32(size);
if (err != NO_ERROR) {
return err;
}
}
if (size) {
void* buffer = writeInplace(size);
if (buffer == NULL)
return NO_MEMORY;
return val.flatten(buffer, size);
}
return NO_ERROR;
}
template<typename T>
status_t Parcel::read(Flattenable<T>& val) const {
FlattenableHelper<T> helper(val);
return read(helper);
}
template<typename T>
status_t Parcel::read(LightFlattenable<T>& val) const {
size_t size;
if (val.isFixedSize()) {
size = val.getFlattenedSize();
} else {
int32_t s;
status_t err = readInt32(&s);
if (err != NO_ERROR) {
return err;
}
size = s;
}
if (size) {
void const* buffer = readInplace(size);
return buffer == NULL ? NO_MEMORY :
val.unflatten(buffer, size);
}
return NO_ERROR;
}
// ---------------------------------------------------------------------------
inline TextOutput& operator<<(TextOutput& to, const Parcel& parcel)
{
parcel.print(to);
return to;
}
// ---------------------------------------------------------------------------
// Generic acquire and release of objects.
void acquire_object(const sp<ProcessState>& proc,
const flat_binder_object& obj, const void* who);
void release_object(const sp<ProcessState>& proc,
const flat_binder_object& obj, const void* who);
void flatten_binder(const sp<ProcessState>& proc,
const sp<IBinder>& binder, flat_binder_object* out);
void flatten_binder(const sp<ProcessState>& proc,
const wp<IBinder>& binder, flat_binder_object* out);
status_t unflatten_binder(const sp<ProcessState>& proc,
const flat_binder_object& flat, sp<IBinder>* out);
status_t unflatten_binder(const sp<ProcessState>& proc,
const flat_binder_object& flat, wp<IBinder>* out);
}; // namespace android
// ---------------------------------------------------------------------------
#endif // ANDROID_PARCEL_H