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 #include <utils/Flattenable.h> 26 27 // --------------------------------------------------------------------------- 28 namespace android { 29 30 template <typename T> class LightFlattenable; 31 class Flattenable; 32 class IBinder; 33 class IPCThreadState; 34 class ProcessState; 35 class String8; 36 class TextOutput; 37 38 struct flat_binder_object; // defined in support_p/binder_module.h 39 40 class Parcel 41 { 42 public: 43 class ReadableBlob; 44 class WritableBlob; 45 46 Parcel(); 47 ~Parcel(); 48 49 const uint8_t* data() const; 50 size_t dataSize() const; 51 size_t dataAvail() const; 52 size_t dataPosition() const; 53 size_t dataCapacity() const; 54 55 status_t setDataSize(size_t size); 56 void setDataPosition(size_t pos) const; 57 status_t setDataCapacity(size_t size); 58 59 status_t setData(const uint8_t* buffer, size_t len); 60 61 status_t appendFrom(const Parcel *parcel, 62 size_t start, size_t len); 63 64 bool pushAllowFds(bool allowFds); 65 void restoreAllowFds(bool lastValue); 66 67 bool hasFileDescriptors() const; 68 69 // Writes the RPC header. 70 status_t writeInterfaceToken(const String16& interface); 71 72 // Parses the RPC header, returning true if the interface name 73 // in the header matches the expected interface from the caller. 74 // 75 // Additionally, enforceInterface does part of the work of 76 // propagating the StrictMode policy mask, populating the current 77 // IPCThreadState, which as an optimization may optionally be 78 // passed in. 79 bool enforceInterface(const String16& interface, 80 IPCThreadState* threadState = NULL) const; 81 bool checkInterface(IBinder*) const; 82 83 void freeData(); 84 85 const size_t* objects() const; 86 size_t objectsCount() const; 87 88 status_t errorCheck() const; 89 void setError(status_t err); 90 91 status_t write(const void* data, size_t len); 92 void* writeInplace(size_t len); 93 status_t writeUnpadded(const void* data, size_t len); 94 status_t writeInt32(int32_t val); 95 status_t writeInt64(int64_t val); 96 status_t writeFloat(float val); 97 status_t writeDouble(double val); 98 status_t writeIntPtr(intptr_t val); 99 status_t writeCString(const char* str); 100 status_t writeString8(const String8& str); 101 status_t writeString16(const String16& str); 102 status_t writeString16(const char16_t* str, size_t len); 103 status_t writeStrongBinder(const sp<IBinder>& val); 104 status_t writeWeakBinder(const wp<IBinder>& val); 105 status_t write(const Flattenable& val); 106 107 template<typename T> 108 status_t write(const LightFlattenable<T>& val); 109 110 111 // Place a native_handle into the parcel (the native_handle's file- 112 // descriptors are dup'ed, so it is safe to delete the native_handle 113 // when this function returns). 114 // Doesn't take ownership of the native_handle. 115 status_t writeNativeHandle(const native_handle* handle); 116 117 // Place a file descriptor into the parcel. The given fd must remain 118 // valid for the lifetime of the parcel. 119 // The Parcel does not take ownership of the given fd unless you ask it to. 120 status_t writeFileDescriptor(int fd, bool takeOwnership = false); 121 122 // Place a file descriptor into the parcel. A dup of the fd is made, which 123 // will be closed once the parcel is destroyed. 124 status_t writeDupFileDescriptor(int fd); 125 126 // Writes a blob to the parcel. 127 // If the blob is small, then it is stored in-place, otherwise it is 128 // transferred by way of an anonymous shared memory region. 129 // The caller should call release() on the blob after writing its contents. 130 status_t writeBlob(size_t len, WritableBlob* outBlob); 131 132 status_t writeObject(const flat_binder_object& val, bool nullMetaData); 133 134 // Like Parcel.java's writeNoException(). Just writes a zero int32. 135 // Currently the native implementation doesn't do any of the StrictMode 136 // stack gathering and serialization that the Java implementation does. 137 status_t writeNoException(); 138 139 void remove(size_t start, size_t amt); 140 141 status_t read(void* outData, size_t len) const; 142 const void* readInplace(size_t len) const; 143 int32_t readInt32() const; 144 status_t readInt32(int32_t *pArg) const; 145 int64_t readInt64() const; 146 status_t readInt64(int64_t *pArg) const; 147 float readFloat() const; 148 status_t readFloat(float *pArg) const; 149 double readDouble() const; 150 status_t readDouble(double *pArg) const; 151 intptr_t readIntPtr() const; 152 status_t readIntPtr(intptr_t *pArg) const; 153 154 const char* readCString() const; 155 String8 readString8() const; 156 String16 readString16() const; 157 const char16_t* readString16Inplace(size_t* outLen) const; 158 sp<IBinder> readStrongBinder() const; 159 wp<IBinder> readWeakBinder() const; 160 status_t read(Flattenable& val) const; 161 162 template<typename T> 163 status_t read(LightFlattenable<T>& val) const; 164 165 // Like Parcel.java's readExceptionCode(). Reads the first int32 166 // off of a Parcel's header, returning 0 or the negative error 167 // code on exceptions, but also deals with skipping over rich 168 // response headers. Callers should use this to read & parse the 169 // response headers rather than doing it by hand. 170 int32_t readExceptionCode() const; 171 172 // Retrieve native_handle from the parcel. This returns a copy of the 173 // parcel's native_handle (the caller takes ownership). The caller 174 // must free the native_handle with native_handle_close() and 175 // native_handle_delete(). 176 native_handle* readNativeHandle() const; 177 178 179 // Retrieve a file descriptor from the parcel. This returns the raw fd 180 // in the parcel, which you do not own -- use dup() to get your own copy. 181 int readFileDescriptor() const; 182 183 // Reads a blob from the parcel. 184 // The caller should call release() on the blob after reading its contents. 185 status_t readBlob(size_t len, ReadableBlob* outBlob) const; 186 187 const flat_binder_object* readObject(bool nullMetaData) const; 188 189 // Explicitly close all file descriptors in the parcel. 190 void closeFileDescriptors(); 191 192 typedef void (*release_func)(Parcel* parcel, 193 const uint8_t* data, size_t dataSize, 194 const size_t* objects, size_t objectsSize, 195 void* cookie); 196 197 const uint8_t* ipcData() const; 198 size_t ipcDataSize() const; 199 const size_t* ipcObjects() const; 200 size_t ipcObjectsCount() const; 201 void ipcSetDataReference(const uint8_t* data, size_t dataSize, 202 const size_t* objects, size_t objectsCount, 203 release_func relFunc, void* relCookie); 204 205 void print(TextOutput& to, uint32_t flags = 0) const; 206 207 private: 208 Parcel(const Parcel& o); 209 Parcel& operator=(const Parcel& o); 210 211 status_t finishWrite(size_t len); 212 void releaseObjects(); 213 void acquireObjects(); 214 status_t growData(size_t len); 215 status_t restartWrite(size_t desired); 216 status_t continueWrite(size_t desired); 217 void freeDataNoInit(); 218 void initState(); 219 void scanForFds() const; 220 221 template<class T> 222 status_t readAligned(T *pArg) const; 223 224 template<class T> T readAligned() const; 225 226 template<class T> 227 status_t writeAligned(T val); 228 229 status_t mError; 230 uint8_t* mData; 231 size_t mDataSize; 232 size_t mDataCapacity; 233 mutable size_t mDataPos; 234 size_t* mObjects; 235 size_t mObjectsSize; 236 size_t mObjectsCapacity; 237 mutable size_t mNextObjectHint; 238 239 mutable bool mFdsKnown; 240 mutable bool mHasFds; 241 bool mAllowFds; 242 243 release_func mOwner; 244 void* mOwnerCookie; 245 246 class Blob { 247 public: 248 Blob(); 249 ~Blob(); 250 251 void release(); 252 inline size_t size() const { return mSize; } 253 254 protected: 255 void init(bool mapped, void* data, size_t size); 256 void clear(); 257 258 bool mMapped; 259 void* mData; 260 size_t mSize; 261 }; 262 263 public: 264 class ReadableBlob : public Blob { 265 friend class Parcel; 266 public: 267 inline const void* data() const { return mData; } 268 }; 269 270 class WritableBlob : public Blob { 271 friend class Parcel; 272 public: 273 inline void* data() { return mData; } 274 }; 275 }; 276 277 // --------------------------------------------------------------------------- 278 279 template<typename T> 280 status_t Parcel::write(const LightFlattenable<T>& val) { 281 size_t size(val.getSize()); 282 if (!val.isFixedSize()) { 283 status_t err = writeInt32(size); 284 if (err != NO_ERROR) { 285 return err; 286 } 287 } 288 if (size) { 289 void* buffer = writeInplace(size); 290 return buffer == NULL ? NO_MEMORY : 291 val.flatten(buffer); 292 } 293 return NO_ERROR; 294 } 295 296 template<typename T> 297 status_t Parcel::read(LightFlattenable<T>& val) const { 298 size_t size; 299 if (val.isFixedSize()) { 300 size = val.getSize(); 301 } else { 302 int32_t s; 303 status_t err = readInt32(&s); 304 if (err != NO_ERROR) { 305 return err; 306 } 307 size = s; 308 } 309 if (size) { 310 void const* buffer = readInplace(size); 311 return buffer == NULL ? NO_MEMORY : 312 val.unflatten(buffer, size); 313 } 314 return NO_ERROR; 315 } 316 317 // --------------------------------------------------------------------------- 318 319 inline TextOutput& operator<<(TextOutput& to, const Parcel& parcel) 320 { 321 parcel.print(to); 322 return to; 323 } 324 325 // --------------------------------------------------------------------------- 326 327 // Generic acquire and release of objects. 328 void acquire_object(const sp<ProcessState>& proc, 329 const flat_binder_object& obj, const void* who); 330 void release_object(const sp<ProcessState>& proc, 331 const flat_binder_object& obj, const void* who); 332 333 void flatten_binder(const sp<ProcessState>& proc, 334 const sp<IBinder>& binder, flat_binder_object* out); 335 void flatten_binder(const sp<ProcessState>& proc, 336 const wp<IBinder>& binder, flat_binder_object* out); 337 status_t unflatten_binder(const sp<ProcessState>& proc, 338 const flat_binder_object& flat, sp<IBinder>* out); 339 status_t unflatten_binder(const sp<ProcessState>& proc, 340 const flat_binder_object& flat, wp<IBinder>* out); 341 342 }; // namespace android 343 344 // --------------------------------------------------------------------------- 345 346 #endif // ANDROID_PARCEL_H 347
