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/OutputFile.h" 18 19 #include <cstdlib> 20 21 #include <llvm/Support/raw_ostream.h> 22 23 #include "bcc/Support/Log.h" 24 25 using namespace bcc; 26 27 OutputFile::OutputFile(const std::string &pFilename, unsigned pFlags) 28 : super(pFilename, pFlags) { } 29 30 ssize_t OutputFile::write(const void *pBuf, size_t count) { 31 if ((mFD < 0) || hasError()) { 32 return -1; 33 } 34 35 if ((count <= 0) || (pBuf == nullptr)) { 36 // Keep safe and issue a warning. 37 ALOGW("OutputFile::write: count = %zu, buffer = %p", count, pBuf); 38 return 0; 39 } 40 41 while (count > 0) { 42 ssize_t write_size = ::write(mFD, pBuf, count); 43 44 if (write_size > 0) { 45 return write_size; 46 } else if ((errno == EAGAIN) || (errno == EINTR)) { 47 // If the errno is EAGAIN or EINTR, then we try to write again. 48 // 49 // Fall-through 50 } else { 51 detectError(); 52 return -1; 53 } 54 } 55 // unreachable 56 return 0; 57 } 58 59 void OutputFile::truncate() { 60 if (mFD < 0) { 61 return; 62 } 63 64 do { 65 if (::ftruncate(mFD, 0) == 0) { 66 return; 67 } 68 } while (errno == EINTR); 69 detectError(); 70 71 return; 72 } 73 74 llvm::raw_fd_ostream *OutputFile::dup() { 75 int newfd; 76 77 do { 78 newfd = ::dup(mFD); 79 if (newfd < 0) { 80 if (errno != EINTR) { 81 detectError(); 82 return nullptr; 83 } 84 // EINTR 85 continue; 86 } 87 // dup() returns ok. 88 break; 89 } while (true); 90 91 llvm::raw_fd_ostream *result = 92 new (std::nothrow) llvm::raw_fd_ostream(newfd, /* shouldClose */true); 93 94 if (result == nullptr) { 95 mError = std::make_error_code(std::errc::not_enough_memory); 96 } 97 98 return result; 99 } 100