1 /* 2 * Copyright (C) 2015 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 "shell_service.h" 18 19 #include <string.h> 20 21 #include <algorithm> 22 23 #include "adb_io.h" 24 ShellProtocol(int fd)25 ShellProtocol::ShellProtocol(int fd) : fd_(fd) { 26 buffer_[0] = kIdInvalid; 27 } 28 ~ShellProtocol()29 ShellProtocol::~ShellProtocol() { 30 } 31 Read()32 bool ShellProtocol::Read() { 33 // Only read a new header if we've finished the last packet. 34 if (!bytes_left_) { 35 if (!ReadFdExactly(fd_, buffer_, kHeaderSize)) { 36 return false; 37 } 38 39 length_t packet_length; 40 memcpy(&packet_length, &buffer_[1], sizeof(packet_length)); 41 bytes_left_ = packet_length; 42 data_length_ = 0; 43 } 44 45 size_t read_length = std::min(bytes_left_, data_capacity()); 46 if (read_length && !ReadFdExactly(fd_, data(), read_length)) { 47 return false; 48 } 49 50 bytes_left_ -= read_length; 51 data_length_ = read_length; 52 53 return true; 54 } 55 Write(Id id,size_t length)56 bool ShellProtocol::Write(Id id, size_t length) { 57 buffer_[0] = id; 58 length_t typed_length = length; 59 memcpy(&buffer_[1], &typed_length, sizeof(typed_length)); 60 61 return WriteFdExactly(fd_, buffer_, kHeaderSize + length); 62 } 63