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 #include <binder/Binder.h> 18 19 #include <utils/Atomic.h> 20 #include <binder/BpBinder.h> 21 #include <binder/IInterface.h> 22 #include <binder/Parcel.h> 23 24 #include <stdio.h> 25 26 namespace android { 27 28 // --------------------------------------------------------------------------- 29 30 IBinder::IBinder() 31 : RefBase() 32 { 33 } 34 35 IBinder::~IBinder() 36 { 37 } 38 39 // --------------------------------------------------------------------------- 40 41 sp<IInterface> IBinder::queryLocalInterface(const String16& descriptor) 42 { 43 return NULL; 44 } 45 46 BBinder* IBinder::localBinder() 47 { 48 return NULL; 49 } 50 51 BpBinder* IBinder::remoteBinder() 52 { 53 return NULL; 54 } 55 56 bool IBinder::checkSubclass(const void* /*subclassID*/) const 57 { 58 return false; 59 } 60 61 // --------------------------------------------------------------------------- 62 63 class BBinder::Extras 64 { 65 public: 66 Mutex mLock; 67 BpBinder::ObjectManager mObjects; 68 }; 69 70 // --------------------------------------------------------------------------- 71 72 BBinder::BBinder() 73 : mExtras(NULL) 74 { 75 } 76 77 bool BBinder::isBinderAlive() const 78 { 79 return true; 80 } 81 82 status_t BBinder::pingBinder() 83 { 84 return NO_ERROR; 85 } 86 87 const String16& BBinder::getInterfaceDescriptor() const 88 { 89 // This is a local static rather than a global static, 90 // to avoid static initializer ordering issues. 91 static String16 sEmptyDescriptor; 92 LOGW("reached BBinder::getInterfaceDescriptor (this=%p)", this); 93 return sEmptyDescriptor; 94 } 95 96 status_t BBinder::transact( 97 uint32_t code, const Parcel& data, Parcel* reply, uint32_t flags) 98 { 99 data.setDataPosition(0); 100 101 status_t err = NO_ERROR; 102 switch (code) { 103 case PING_TRANSACTION: 104 reply->writeInt32(pingBinder()); 105 break; 106 default: 107 err = onTransact(code, data, reply, flags); 108 break; 109 } 110 111 if (reply != NULL) { 112 reply->setDataPosition(0); 113 } 114 115 return err; 116 } 117 118 status_t BBinder::linkToDeath( 119 const sp<DeathRecipient>& recipient, void* cookie, uint32_t flags) 120 { 121 return INVALID_OPERATION; 122 } 123 124 status_t BBinder::unlinkToDeath( 125 const wp<DeathRecipient>& recipient, void* cookie, uint32_t flags, 126 wp<DeathRecipient>* outRecipient) 127 { 128 return INVALID_OPERATION; 129 } 130 131 status_t BBinder::dump(int fd, const Vector<String16>& args) 132 { 133 return NO_ERROR; 134 } 135 136 void BBinder::attachObject( 137 const void* objectID, void* object, void* cleanupCookie, 138 object_cleanup_func func) 139 { 140 Extras* e = mExtras; 141 142 if (!e) { 143 e = new Extras; 144 if (android_atomic_cmpxchg(0, reinterpret_cast<int32_t>(e), 145 reinterpret_cast<volatile int32_t*>(&mExtras)) != 0) { 146 delete e; 147 e = mExtras; 148 } 149 if (e == 0) return; // out of memory 150 } 151 152 AutoMutex _l(e->mLock); 153 e->mObjects.attach(objectID, object, cleanupCookie, func); 154 } 155 156 void* BBinder::findObject(const void* objectID) const 157 { 158 Extras* e = mExtras; 159 if (!e) return NULL; 160 161 AutoMutex _l(e->mLock); 162 return e->mObjects.find(objectID); 163 } 164 165 void BBinder::detachObject(const void* objectID) 166 { 167 Extras* e = mExtras; 168 if (!e) return; 169 170 AutoMutex _l(e->mLock); 171 e->mObjects.detach(objectID); 172 } 173 174 BBinder* BBinder::localBinder() 175 { 176 return this; 177 } 178 179 BBinder::~BBinder() 180 { 181 if (mExtras) delete mExtras; 182 } 183 184 185 status_t BBinder::onTransact( 186 uint32_t code, const Parcel& data, Parcel* reply, uint32_t flags) 187 { 188 switch (code) { 189 case INTERFACE_TRANSACTION: 190 reply->writeString16(getInterfaceDescriptor()); 191 return NO_ERROR; 192 193 case DUMP_TRANSACTION: { 194 int fd = data.readFileDescriptor(); 195 int argc = data.readInt32(); 196 Vector<String16> args; 197 for (int i = 0; i < argc && data.dataAvail() > 0; i++) { 198 args.add(data.readString16()); 199 } 200 return dump(fd, args); 201 } 202 default: 203 return UNKNOWN_TRANSACTION; 204 } 205 } 206 207 // --------------------------------------------------------------------------- 208 209 enum { 210 // This is used to transfer ownership of the remote binder from 211 // the BpRefBase object holding it (when it is constructed), to the 212 // owner of the BpRefBase object when it first acquires that BpRefBase. 213 kRemoteAcquired = 0x00000001 214 }; 215 216 BpRefBase::BpRefBase(const sp<IBinder>& o) 217 : mRemote(o.get()), mRefs(NULL), mState(0) 218 { 219 extendObjectLifetime(OBJECT_LIFETIME_WEAK); 220 221 if (mRemote) { 222 mRemote->incStrong(this); // Removed on first IncStrong(). 223 mRefs = mRemote->createWeak(this); // Held for our entire lifetime. 224 } 225 } 226 227 BpRefBase::~BpRefBase() 228 { 229 if (mRemote) { 230 if (!(mState&kRemoteAcquired)) { 231 mRemote->decStrong(this); 232 } 233 mRefs->decWeak(this); 234 } 235 } 236 237 void BpRefBase::onFirstRef() 238 { 239 android_atomic_or(kRemoteAcquired, &mState); 240 } 241 242 void BpRefBase::onLastStrongRef(const void* id) 243 { 244 if (mRemote) { 245 mRemote->decStrong(this); 246 } 247 } 248 249 bool BpRefBase::onIncStrongAttempted(uint32_t flags, const void* id) 250 { 251 return mRemote ? mRefs->attemptIncStrong(this) : false; 252 } 253 254 // --------------------------------------------------------------------------- 255 256 }; // namespace android 257
