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 class IShellCallback; 42 43 /** 44 * Base class and low-level protocol for a remotable object. 45 * You can derive from this class to create an object for which other 46 * processes can hold references to it. Communication between processes 47 * (method calls, property get and set) is down through a low-level 48 * protocol implemented on top of the transact() API. 49 */ 50 class IBinder : public virtual RefBase 51 { 52 public: 53 enum { 54 FIRST_CALL_TRANSACTION = 0x00000001, 55 LAST_CALL_TRANSACTION = 0x00ffffff, 56 57 PING_TRANSACTION = B_PACK_CHARS('_','P','N','G'), 58 DUMP_TRANSACTION = B_PACK_CHARS('_','D','M','P'), 59 SHELL_COMMAND_TRANSACTION = B_PACK_CHARS('_','C','M','D'), 60 INTERFACE_TRANSACTION = B_PACK_CHARS('_', 'N', 'T', 'F'), 61 SYSPROPS_TRANSACTION = B_PACK_CHARS('_', 'S', 'P', 'R'), 62 63 // Corresponds to TF_ONE_WAY -- an asynchronous call. 64 FLAG_ONEWAY = 0x00000001 65 }; 66 67 IBinder(); 68 69 /** 70 * Check if this IBinder implements the interface named by 71 * @a descriptor. If it does, the base pointer to it is returned, 72 * which you can safely static_cast<> to the concrete C++ interface. 73 */ 74 virtual sp<IInterface> queryLocalInterface(const String16& descriptor); 75 76 /** 77 * Return the canonical name of the interface provided by this IBinder 78 * object. 79 */ 80 virtual const String16& getInterfaceDescriptor() const = 0; 81 82 virtual bool isBinderAlive() const = 0; 83 virtual status_t pingBinder() = 0; 84 virtual status_t dump(int fd, const Vector<String16>& args) = 0; 85 static status_t shellCommand(const sp<IBinder>& target, int in, int out, int err, 86 Vector<String16>& args, const sp<IShellCallback>& callback, 87 const sp<IResultReceiver>& resultReceiver); 88 89 virtual status_t transact( uint32_t code, 90 const Parcel& data, 91 Parcel* reply, 92 uint32_t flags = 0) = 0; 93 94 // DeathRecipient is pure abstract, there is no virtual method 95 // implementation to put in a translation unit in order to silence the 96 // weak vtables warning. 97 #if defined(__clang__) 98 #pragma clang diagnostic push 99 #pragma clang diagnostic ignored "-Wweak-vtables" 100 #endif 101 102 class DeathRecipient : public virtual RefBase 103 { 104 public: 105 virtual void binderDied(const wp<IBinder>& who) = 0; 106 }; 107 108 #if defined(__clang__) 109 #pragma clang diagnostic pop 110 #endif 111 112 /** 113 * Register the @a recipient for a notification if this binder 114 * goes away. If this binder object unexpectedly goes away 115 * (typically because its hosting process has been killed), 116 * then DeathRecipient::binderDied() will be called with a reference 117 * to this. 118 * 119 * The @a cookie is optional -- if non-NULL, it should be a 120 * memory address that you own (that is, you know it is unique). 121 * 122 * @note You will only receive death notifications for remote binders, 123 * as local binders by definition can't die without you dying as well. 124 * Trying to use this function on a local binder will result in an 125 * INVALID_OPERATION code being returned and nothing happening. 126 * 127 * @note This link always holds a weak reference to its recipient. 128 * 129 * @note You will only receive a weak reference to the dead 130 * binder. You should not try to promote this to a strong reference. 131 * (Nor should you need to, as there is nothing useful you can 132 * directly do with it now that it has passed on.) 133 */ 134 virtual status_t linkToDeath(const sp<DeathRecipient>& recipient, 135 void* cookie = NULL, 136 uint32_t flags = 0) = 0; 137 138 /** 139 * Remove a previously registered death notification. 140 * The @a recipient will no longer be called if this object 141 * dies. The @a cookie is optional. If non-NULL, you can 142 * supply a NULL @a recipient, and the recipient previously 143 * added with that cookie will be unlinked. 144 */ 145 virtual status_t unlinkToDeath( const wp<DeathRecipient>& recipient, 146 void* cookie = NULL, 147 uint32_t flags = 0, 148 wp<DeathRecipient>* outRecipient = NULL) = 0; 149 150 virtual bool checkSubclass(const void* subclassID) const; 151 152 typedef void (*object_cleanup_func)(const void* id, void* obj, void* cleanupCookie); 153 154 virtual void attachObject( const void* objectID, 155 void* object, 156 void* cleanupCookie, 157 object_cleanup_func func) = 0; 158 virtual void* findObject(const void* objectID) const = 0; 159 virtual void detachObject(const void* objectID) = 0; 160 161 virtual BBinder* localBinder(); 162 virtual BpBinder* remoteBinder(); 163 164 protected: 165 virtual ~IBinder(); 166 167 private: 168 }; 169 170 }; // namespace android 171 172 // --------------------------------------------------------------------------- 173 174 #endif // ANDROID_IBINDER_H 175