1 /* 2 * Copyright 2012, 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 "bcc/Support/InputFile.h" 18 19 #include "bcc/Support/Log.h" 20 21 using namespace bcc; 22 23 InputFile::InputFile(const std::string &pFilename, unsigned pFlags) 24 : super(pFilename, pFlags) { } 25 26 ssize_t InputFile::read(void *pBuf, size_t count) { 27 if ((mFD < 0) || hasError()) { 28 return -1; 29 } 30 31 if ((count <= 0) || (pBuf == nullptr)) { 32 // Keep safe and issue a warning. 33 ALOGW("InputFile::read: count = %zu, buffer = %p", count, pBuf); 34 return 0; 35 } 36 37 while (count > 0) { 38 ssize_t read_size = ::read(mFD, pBuf, count); 39 40 if (read_size >= 0) { 41 return read_size; 42 } else if ((errno == EAGAIN) || (errno == EINTR)) { 43 // If the errno is EAGAIN or EINTR, then we try to read again. 44 // 45 // Fall-through 46 } else { 47 detectError(); 48 return -1; 49 } 50 } 51 // unreachable 52 return 0; 53 } 54
