1 /* 2 * Copyright (C) 2007 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 /** 18 * IPC messaging library. 19 */ 20 21 #ifndef __MQ_H 22 #define __MQ_H 23 24 #ifdef __cplusplus 25 extern "C" { 26 #endif 27 28 /** A message. */ 29 typedef struct MqMessage MqMessage; 30 31 /** A destination to which messages can be sent. */ 32 typedef struct MqDestination MqDestination; 33 34 /* Array of bytes. */ 35 typedef struct MqBytes MqBytes; 36 37 /** 38 * Hears messages. 39 * 40 * @param destination to which the message was sent 41 * @param message the message to hear 42 */ 43 typedef void MqMessageListener(MqDestination* destination, MqMessage* message); 44 45 /** 46 * Hears a destination close. 47 * 48 * @param destination that closed 49 */ 50 typedef void MqCloseListener(MqDestination* destination); 51 52 /** Message functions. */ 53 54 /** 55 * Creates a new Message. 56 * 57 * @param header as defined by user 58 * @param body as defined by user 59 * @param replyTo destination to which replies should be sent, NULL if none 60 */ 61 MqMessage* mqCreateMessage(MqBytes header, MqBytes body, 62 MqDestination* replyTo); 63 64 /** Sends a message to a destination. */ 65 void mqSendMessage(MqMessage* message, MqDestination* destination); 66 67 /** Destination functions. */ 68 69 /** 70 * Creates a new destination. Acquires a reference implicitly. 71 * 72 * @param messageListener function to call when a message is recieved 73 * @param closeListener function to call when the destination closes 74 * @param userData user-specific data to associate with the destination. 75 * Retrieve using mqGetDestinationUserData(). 76 */ 77 MqDestination* mqCreateDestination(MqMessageListener* messageListener, 78 MqCloseListener* closeListener, void* userData); 79 80 /** 81 * Gets user data which was associated with the given destination at 82 * construction time. 83 * 84 * It is only valid to call this function in the same process that the 85 * given destination was created in. 86 * This function returns a null pointer if you call it on a destination 87 * created in a remote process. 88 */ 89 void* mqGetUserData(MqDestination* destination); 90 91 /** 92 * Returns 1 if the destination was created in this process, or 0 if 93 * the destination was created in a different process, in which case you have 94 * a remote stub. 95 */ 96 int mqIsDestinationLocal(MqDestination* destination); 97 98 /** 99 * Increments the destination's reference count. 100 */ 101 void mqKeepDestination(MqDesintation* destination); 102 103 /** 104 * Decrements the destination's reference count. 105 */ 106 void mqFreeDestination(MqDestination* desintation); 107 108 /** Registry API. */ 109 110 /** 111 * Gets the destination bound to a name. 112 */ 113 MqDestination* mqGetDestination(char* name); 114 115 /** 116 * Binds a destination to a name. 117 */ 118 void mqPutDestination(char* name, MqDestination* desintation); 119 120 #ifdef __cplusplus 121 } 122 #endif 123 124 #endif /* __MQ_H */ 125