Parcel.h revision 8acda7803417cc38cb284298fcb86b479d11fdb5
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#ifndef ANDROID_PARCEL_H 18#define ANDROID_PARCEL_H 19 20#include <cutils/native_handle.h> 21#include <utils/Errors.h> 22#include <utils/RefBase.h> 23#include <utils/String16.h> 24#include <utils/Vector.h> 25 26// --------------------------------------------------------------------------- 27namespace android { 28 29class Flattenable; 30class IBinder; 31class IPCThreadState; 32class ProcessState; 33class String8; 34class TextOutput; 35 36struct flat_binder_object; // defined in support_p/binder_module.h 37 38class Parcel 39{ 40public: 41 Parcel(); 42 ~Parcel(); 43 44 const uint8_t* data() const; 45 size_t dataSize() const; 46 size_t dataAvail() const; 47 size_t dataPosition() const; 48 size_t dataCapacity() const; 49 50 status_t setDataSize(size_t size); 51 void setDataPosition(size_t pos) const; 52 status_t setDataCapacity(size_t size); 53 54 status_t setData(const uint8_t* buffer, size_t len); 55 56 status_t appendFrom(const Parcel *parcel, 57 size_t start, size_t len); 58 59 bool hasFileDescriptors() const; 60 61 // Writes the RPC header. 62 status_t writeInterfaceToken(const String16& interface); 63 64 // Parses the RPC header, returning true if the interface name 65 // in the header matches the expected interface from the caller. 66 // 67 // Additionally, enforceInterface does part of the work of 68 // propagating the StrictMode policy mask, populating the current 69 // IPCThreadState, which as an optimization may optionally be 70 // passed in. 71 bool enforceInterface(const String16& interface, 72 IPCThreadState* threadState = NULL) const; 73 bool checkInterface(IBinder*) const; 74 75 void freeData(); 76 77 const size_t* objects() const; 78 size_t objectsCount() const; 79 80 status_t errorCheck() const; 81 void setError(status_t err); 82 83 status_t write(const void* data, size_t len); 84 void* writeInplace(size_t len); 85 status_t writeUnpadded(const void* data, size_t len); 86 status_t writeInt32(int32_t val); 87 status_t writeInt64(int64_t val); 88 status_t writeFloat(float val); 89 status_t writeDouble(double val); 90 status_t writeIntPtr(intptr_t val); 91 status_t writeCString(const char* str); 92 status_t writeString8(const String8& str); 93 status_t writeString16(const String16& str); 94 status_t writeString16(const char16_t* str, size_t len); 95 status_t writeStrongBinder(const sp<IBinder>& val); 96 status_t writeWeakBinder(const wp<IBinder>& val); 97 status_t write(const Flattenable& val); 98 99 // Place a native_handle into the parcel (the native_handle's file- 100 // descriptors are dup'ed, so it is safe to delete the native_handle 101 // when this function returns). 102 // Doesn't take ownership of the native_handle. 103 status_t writeNativeHandle(const native_handle* handle); 104 105 // Place a file descriptor into the parcel. The given fd must remain 106 // valid for the lifetime of the parcel. 107 status_t writeFileDescriptor(int fd); 108 109 // Place a file descriptor into the parcel. A dup of the fd is made, which 110 // will be closed once the parcel is destroyed. 111 status_t writeDupFileDescriptor(int fd); 112 113 status_t writeObject(const flat_binder_object& val, bool nullMetaData); 114 115 // Like Parcel.java's writeNoException(). Just writes a zero int32. 116 // Currently the native implementation doesn't do any of the StrictMode 117 // stack gathering and serialization that the Java implementation does. 118 status_t writeNoException(); 119 120 void remove(size_t start, size_t amt); 121 122 status_t read(void* outData, size_t len) const; 123 const void* readInplace(size_t len) const; 124 int32_t readInt32() const; 125 status_t readInt32(int32_t *pArg) const; 126 int64_t readInt64() const; 127 status_t readInt64(int64_t *pArg) const; 128 float readFloat() const; 129 status_t readFloat(float *pArg) const; 130 double readDouble() const; 131 status_t readDouble(double *pArg) const; 132 intptr_t readIntPtr() const; 133 status_t readIntPtr(intptr_t *pArg) const; 134 135 const char* readCString() const; 136 String8 readString8() const; 137 String16 readString16() const; 138 const char16_t* readString16Inplace(size_t* outLen) const; 139 sp<IBinder> readStrongBinder() const; 140 wp<IBinder> readWeakBinder() const; 141 status_t read(Flattenable& val) const; 142 143 // Like Parcel.java's readExceptionCode(). Reads the first int32 144 // off of a Parcel's header, returning 0 or the negative error 145 // code on exceptions, but also deals with skipping over rich 146 // response headers. Callers should use this to read & parse the 147 // response headers rather than doing it by hand. 148 int32_t readExceptionCode() const; 149 150 // Retrieve native_handle from the parcel. This returns a copy of the 151 // parcel's native_handle (the caller takes ownership). The caller 152 // must free the native_handle with native_handle_close() and 153 // native_handle_delete(). 154 native_handle* readNativeHandle() const; 155 156 157 // Retrieve a file descriptor from the parcel. This returns the raw fd 158 // in the parcel, which you do not own -- use dup() to get your own copy. 159 int readFileDescriptor() const; 160 161 const flat_binder_object* readObject(bool nullMetaData) const; 162 163 // Explicitly close all file descriptors in the parcel. 164 void closeFileDescriptors(); 165 166 typedef void (*release_func)(Parcel* parcel, 167 const uint8_t* data, size_t dataSize, 168 const size_t* objects, size_t objectsSize, 169 void* cookie); 170 171 const uint8_t* ipcData() const; 172 size_t ipcDataSize() const; 173 const size_t* ipcObjects() const; 174 size_t ipcObjectsCount() const; 175 void ipcSetDataReference(const uint8_t* data, size_t dataSize, 176 const size_t* objects, size_t objectsCount, 177 release_func relFunc, void* relCookie); 178 179 void print(TextOutput& to, uint32_t flags = 0) const; 180 181private: 182 Parcel(const Parcel& o); 183 Parcel& operator=(const Parcel& o); 184 185 status_t finishWrite(size_t len); 186 void releaseObjects(); 187 void acquireObjects(); 188 status_t growData(size_t len); 189 status_t restartWrite(size_t desired); 190 status_t continueWrite(size_t desired); 191 void freeDataNoInit(); 192 void initState(); 193 void scanForFds() const; 194 195 template<class T> 196 status_t readAligned(T *pArg) const; 197 198 template<class T> T readAligned() const; 199 200 template<class T> 201 status_t writeAligned(T val); 202 203 status_t mError; 204 uint8_t* mData; 205 size_t mDataSize; 206 size_t mDataCapacity; 207 mutable size_t mDataPos; 208 size_t* mObjects; 209 size_t mObjectsSize; 210 size_t mObjectsCapacity; 211 mutable size_t mNextObjectHint; 212 213 mutable bool mFdsKnown; 214 mutable bool mHasFds; 215 216 release_func mOwner; 217 void* mOwnerCookie; 218}; 219 220// --------------------------------------------------------------------------- 221 222inline TextOutput& operator<<(TextOutput& to, const Parcel& parcel) 223{ 224 parcel.print(to); 225 return to; 226} 227 228// --------------------------------------------------------------------------- 229 230// Generic acquire and release of objects. 231void acquire_object(const sp<ProcessState>& proc, 232 const flat_binder_object& obj, const void* who); 233void release_object(const sp<ProcessState>& proc, 234 const flat_binder_object& obj, const void* who); 235 236void flatten_binder(const sp<ProcessState>& proc, 237 const sp<IBinder>& binder, flat_binder_object* out); 238void flatten_binder(const sp<ProcessState>& proc, 239 const wp<IBinder>& binder, flat_binder_object* out); 240status_t unflatten_binder(const sp<ProcessState>& proc, 241 const flat_binder_object& flat, sp<IBinder>* out); 242status_t unflatten_binder(const sp<ProcessState>& proc, 243 const flat_binder_object& flat, wp<IBinder>* out); 244 245}; // namespace android 246 247// --------------------------------------------------------------------------- 248 249#endif // ANDROID_PARCEL_H 250