1 /* 2 * Copyright (C) 2008 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_IBINDER_H 18 #define ANDROID_IBINDER_H 19 20 #include <utils/Errors.h> 21 #include <utils/RefBase.h> 22 #include <utils/String16.h> 23 #include <utils/Vector.h> 24 25 26 // linux/binder.h already defines this, but we can't just include it from there 27 // because there are host builds that include this file. 28 #ifndef B_PACK_CHARS 29 #define B_PACK_CHARS(c1, c2, c3, c4) \ 30 ((((c1)<<24)) | (((c2)<<16)) | (((c3)<<8)) | (c4)) 31 #endif // B_PACK_CHARS 32 33 // --------------------------------------------------------------------------- 34 namespace android { 35 36 class BBinder; 37 class BpBinder; 38 class IInterface; 39 class Parcel; 40 class IResultReceiver; 41 42 /** 43 * Base class and low-level protocol for a remotable object. 44 * You can derive from this class to create an object for which other 45 * processes can hold references to it. Communication between processes 46 * (method calls, property get and set) is down through a low-level 47 * protocol implemented on top of the transact() API. 48 */ 49 class IBinder : public virtual RefBase 50 { 51 public: 52 enum { 53 FIRST_CALL_TRANSACTION = 0x00000001, 54 LAST_CALL_TRANSACTION = 0x00ffffff, 55 56 PING_TRANSACTION = B_PACK_CHARS('_','P','N','G'), 57 DUMP_TRANSACTION = B_PACK_CHARS('_','D','M','P'), 58 SHELL_COMMAND_TRANSACTION = B_PACK_CHARS('_','C','M','D'), 59 INTERFACE_TRANSACTION = B_PACK_CHARS('_', 'N', 'T', 'F'), 60 SYSPROPS_TRANSACTION = B_PACK_CHARS('_', 'S', 'P', 'R'), 61 62 // Corresponds to TF_ONE_WAY -- an asynchronous call. 63 FLAG_ONEWAY = 0x00000001 64 }; 65 66 IBinder(); 67 68 /** 69 * Check if this IBinder implements the interface named by 70 * @a descriptor. If it does, the base pointer to it is returned, 71 * which you can safely static_cast<> to the concrete C++ interface. 72 */ 73 virtual sp<IInterface> queryLocalInterface(const String16& descriptor); 74 75 /** 76 * Return the canonical name of the interface provided by this IBinder 77 * object. 78 */ 79 virtual const String16& getInterfaceDescriptor() const = 0; 80 81 virtual bool isBinderAlive() const = 0; 82 virtual status_t pingBinder() = 0; 83 virtual status_t dump(int fd, const Vector<String16>& args) = 0; 84 static status_t shellCommand(const sp<IBinder>& target, int in, int out, int err, 85 Vector<String16>& args, 86 const sp<IResultReceiver>& resultReceiver); 87 88 virtual status_t transact( uint32_t code, 89 const Parcel& data, 90 Parcel* reply, 91 uint32_t flags = 0) = 0; 92 93 class DeathRecipient : public virtual RefBase 94 { 95 public: 96 virtual void binderDied(const wp<IBinder>& who) = 0; 97 }; 98 99 /** 100 * Register the @a recipient for a notification if this binder 101 * goes away. If this binder object unexpectedly goes away 102 * (typically because its hosting process has been killed), 103 * then DeathRecipient::binderDied() will be called with a reference 104 * to this. 105 * 106 * The @a cookie is optional -- if non-NULL, it should be a 107 * memory address that you own (that is, you know it is unique). 108 * 109 * @note You will only receive death notifications for remote binders, 110 * as local binders by definition can't die without you dying as well. 111 * Trying to use this function on a local binder will result in an 112 * INVALID_OPERATION code being returned and nothing happening. 113 * 114 * @note This link always holds a weak reference to its recipient. 115 * 116 * @note You will only receive a weak reference to the dead 117 * binder. You should not try to promote this to a strong reference. 118 * (Nor should you need to, as there is nothing useful you can 119 * directly do with it now that it has passed on.) 120 */ 121 virtual status_t linkToDeath(const sp<DeathRecipient>& recipient, 122 void* cookie = NULL, 123 uint32_t flags = 0) = 0; 124 125 /** 126 * Remove a previously registered death notification. 127 * The @a recipient will no longer be called if this object 128 * dies. The @a cookie is optional. If non-NULL, you can 129 * supply a NULL @a recipient, and the recipient previously 130 * added with that cookie will be unlinked. 131 */ 132 virtual status_t unlinkToDeath( const wp<DeathRecipient>& recipient, 133 void* cookie = NULL, 134 uint32_t flags = 0, 135 wp<DeathRecipient>* outRecipient = NULL) = 0; 136 137 virtual bool checkSubclass(const void* subclassID) const; 138 139 typedef void (*object_cleanup_func)(const void* id, void* obj, void* cleanupCookie); 140 141 virtual void attachObject( const void* objectID, 142 void* object, 143 void* cleanupCookie, 144 object_cleanup_func func) = 0; 145 virtual void* findObject(const void* objectID) const = 0; 146 virtual void detachObject(const void* objectID) = 0; 147 148 virtual BBinder* localBinder(); 149 virtual BpBinder* remoteBinder(); 150 151 protected: 152 virtual ~IBinder(); 153 154 private: 155 }; 156 157 }; // namespace android 158 159 // --------------------------------------------------------------------------- 160 161 #endif // ANDROID_IBINDER_H 162