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 // Copied from system/extras/memory_replay/LineBuffer.cpp 18 // TODO(ccross): find a way to share between libmemunreachable and memory_replay? 19 20 #include <errno.h> 21 #include <string.h> 22 #include <unistd.h> 23 24 #include "LineBuffer.h" 25 26 namespace android { 27 28 LineBuffer::LineBuffer(int fd, char* buffer, size_t buffer_len) 29 : fd_(fd), buffer_(buffer), buffer_len_(buffer_len) {} 30 31 bool LineBuffer::GetLine(char** line, size_t* line_len) { 32 while (true) { 33 if (bytes_ > 0) { 34 char* newline = reinterpret_cast<char*>(memchr(buffer_ + start_, '\n', bytes_)); 35 if (newline != nullptr) { 36 *newline = '\0'; 37 *line = buffer_ + start_; 38 start_ = newline - buffer_ + 1; 39 bytes_ -= newline - *line + 1; 40 *line_len = newline - *line; 41 return true; 42 } 43 } 44 if (start_ > 0) { 45 // Didn't find anything, copy the current to the front of the buffer. 46 memmove(buffer_, buffer_ + start_, bytes_); 47 start_ = 0; 48 } 49 ssize_t bytes = TEMP_FAILURE_RETRY(read(fd_, buffer_ + bytes_, buffer_len_ - bytes_ - 1)); 50 if (bytes <= 0) { 51 if (bytes_ > 0) { 52 // The read data might not contain a nul terminator, so add one. 53 buffer_[bytes_] = '\0'; 54 *line = buffer_ + start_; 55 *line_len = bytes_; 56 bytes_ = 0; 57 start_ = 0; 58 return true; 59 } 60 return false; 61 } 62 bytes_ += bytes; 63 } 64 } 65 66 } // namespace android 67