1 /* 2 * Copyright (C) 2010 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_GUI_SENSOR_CHANNEL_H 18 #define ANDROID_GUI_SENSOR_CHANNEL_H 19 20 #include <stdint.h> 21 #include <sys/types.h> 22 23 #include <utils/Errors.h> 24 #include <utils/RefBase.h> 25 #include <cutils/log.h> 26 27 28 namespace android { 29 // ---------------------------------------------------------------------------- 30 class Parcel; 31 32 class BitTube : public RefBase 33 { 34 public: 35 36 // creates a BitTube with a default (4KB) send buffer 37 BitTube(); 38 39 // creates a BitTube with a a specified send and receive buffer size 40 explicit BitTube(size_t bufsize); 41 42 explicit BitTube(const Parcel& data); 43 virtual ~BitTube(); 44 45 // check state after construction 46 status_t initCheck() const; 47 48 // get receive file-descriptor 49 int getFd() const; 50 51 // get the send file-descriptor. 52 int getSendFd() const; 53 54 // send objects (sized blobs). All objects are guaranteed to be written or the call fails. 55 template <typename T> 56 static ssize_t sendObjects(const sp<BitTube>& tube, 57 T const* events, size_t count) { 58 return sendObjects(tube, events, count, sizeof(T)); 59 } 60 61 // receive objects (sized blobs). If the receiving buffer isn't large enough, 62 // excess messages are silently discarded. 63 template <typename T> 64 static ssize_t recvObjects(const sp<BitTube>& tube, 65 T* events, size_t count) { 66 return recvObjects(tube, events, count, sizeof(T)); 67 } 68 69 // parcels this BitTube 70 status_t writeToParcel(Parcel* reply) const; 71 72 private: 73 void init(size_t rcvbuf, size_t sndbuf); 74 75 // send a message. The write is guaranteed to send the whole message or fail. 76 ssize_t write(void const* vaddr, size_t size); 77 78 // receive a message. the passed buffer must be at least as large as the 79 // write call used to send the message, excess data is silently discarded. 80 ssize_t read(void* vaddr, size_t size); 81 82 int mSendFd; 83 mutable int mReceiveFd; 84 85 static ssize_t sendObjects(const sp<BitTube>& tube, 86 void const* events, size_t count, size_t objSize); 87 88 static ssize_t recvObjects(const sp<BitTube>& tube, 89 void* events, size_t count, size_t objSize); 90 }; 91 92 // ---------------------------------------------------------------------------- 93 }; // namespace android 94 95 #endif // ANDROID_GUI_SENSOR_CHANNEL_H 96
