175 lines · cpp
1//===- llvm/unittest/Support/ReplaceFileTest.cpp - unit tests -------------===//2//3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.4// See https://llvm.org/LICENSE.txt for license information.5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception6//7//===----------------------------------------------------------------------===//8 9#include "llvm/Support/Errc.h"10#include "llvm/Support/ErrorHandling.h"11#include "llvm/Support/FileSystem.h"12#include "llvm/Support/MemoryBuffer.h"13#include "llvm/Support/Path.h"14#include "llvm/Support/Process.h"15#include "gtest/gtest.h"16 17using namespace llvm;18using namespace llvm::sys;19 20#define ASSERT_NO_ERROR(x) \21 do { \22 if (std::error_code ASSERT_NO_ERROR_ec = x) { \23 errs() << #x ": did not return errc::success.\n" \24 << "error number: " << ASSERT_NO_ERROR_ec.value() << "\n" \25 << "error message: " << ASSERT_NO_ERROR_ec.message() << "\n"; \26 } \27 } while (false)28 29namespace {30std::error_code CreateFileWithContent(const SmallString<128> &FilePath,31 const StringRef &content) {32 int FD = 0;33 if (std::error_code ec = fs::openFileForWrite(FilePath, FD))34 return ec;35 36 const bool ShouldClose = true;37 raw_fd_ostream OS(FD, ShouldClose);38 OS << content;39 40 return std::error_code();41}42 43class ScopedFD {44 int FD;45 46 ScopedFD(const ScopedFD &) = delete;47 ScopedFD &operator=(const ScopedFD &) = delete;48 49 public:50 explicit ScopedFD(int Descriptor) : FD(Descriptor) {}51 ~ScopedFD() { Process::SafelyCloseFileDescriptor(FD); }52};53 54bool FDHasContent(int FD, StringRef Content) {55 auto Buffer =56 MemoryBuffer::getOpenFile(sys::fs::convertFDToNativeFile(FD), "", -1);57 assert(Buffer);58 return Buffer.get()->getBuffer() == Content;59}60 61bool FileHasContent(StringRef File, StringRef Content) {62 int FD = 0;63 auto EC = fs::openFileForRead(File, FD);64 (void)EC;65 assert(!EC);66 ScopedFD EventuallyCloseIt(FD);67 return FDHasContent(FD, Content);68}69 70TEST(rename, FileOpenedForReadingCanBeReplaced) {71 // Create unique temporary directory for this test.72 SmallString<128> TestDirectory;73 ASSERT_NO_ERROR(fs::createUniqueDirectory(74 "FileOpenedForReadingCanBeReplaced-test", TestDirectory));75 76 // Add a couple of files to the test directory.77 SmallString<128> SourceFileName(TestDirectory);78 path::append(SourceFileName, "source");79 80 SmallString<128> TargetFileName(TestDirectory);81 path::append(TargetFileName, "target");82 83 ASSERT_NO_ERROR(CreateFileWithContent(SourceFileName, "!!source!!"));84 ASSERT_NO_ERROR(CreateFileWithContent(TargetFileName, "!!target!!"));85 86 {87 // Open the target file for reading.88 int ReadFD = 0;89 ASSERT_NO_ERROR(fs::openFileForRead(TargetFileName, ReadFD));90 ScopedFD EventuallyCloseIt(ReadFD);91 92 // Confirm we can replace the file while it is open.93 EXPECT_TRUE(!fs::rename(SourceFileName, TargetFileName));94 95 // We should still be able to read the old data through the existing96 // descriptor.97 EXPECT_TRUE(FDHasContent(ReadFD, "!!target!!"));98 99 // The source file should no longer exist100 EXPECT_FALSE(fs::exists(SourceFileName));101 }102 103 // If we obtain a new descriptor for the target file, we should find that it104 // contains the content that was in the source file.105 EXPECT_TRUE(FileHasContent(TargetFileName, "!!source!!"));106 107 // Rename the target file back to the source file name to confirm that rename108 // still works if the destination does not already exist.109 EXPECT_TRUE(!fs::rename(TargetFileName, SourceFileName));110 EXPECT_FALSE(fs::exists(TargetFileName));111 ASSERT_TRUE(fs::exists(SourceFileName));112 113 // Clean up.114 ASSERT_NO_ERROR(fs::remove(SourceFileName));115 ASSERT_NO_ERROR(fs::remove(TestDirectory.str()));116}117 118TEST(rename, ExistingTemp) {119 // Test that existing .tmpN files don't get deleted by the Windows120 // sys::fs::rename implementation.121 SmallString<128> TestDirectory;122 ASSERT_NO_ERROR(123 fs::createUniqueDirectory("ExistingTemp-test", TestDirectory));124 125 SmallString<128> SourceFileName(TestDirectory);126 path::append(SourceFileName, "source");127 128 SmallString<128> TargetFileName(TestDirectory);129 path::append(TargetFileName, "target");130 131 SmallString<128> TargetTmp0FileName(TestDirectory);132 path::append(TargetTmp0FileName, "target.tmp0");133 134 SmallString<128> TargetTmp1FileName(TestDirectory);135 path::append(TargetTmp1FileName, "target.tmp1");136 137 ASSERT_NO_ERROR(CreateFileWithContent(SourceFileName, "!!source!!"));138 ASSERT_NO_ERROR(CreateFileWithContent(TargetFileName, "!!target!!"));139 ASSERT_NO_ERROR(CreateFileWithContent(TargetTmp0FileName, "!!target.tmp0!!"));140 141 {142 // Use mapped_file_region to make sure that the destination file is mmap'ed.143 // This will cause SetInformationByHandle to fail when renaming to the144 // destination, and we will follow the code path that tries to give target145 // a temporary name.146 int TargetFD;147 std::error_code EC;148 ASSERT_NO_ERROR(fs::openFileForRead(TargetFileName, TargetFD));149 ScopedFD X(TargetFD);150 sys::fs::mapped_file_region MFR(sys::fs::convertFDToNativeFile(TargetFD),151 sys::fs::mapped_file_region::readonly, 10,152 0, EC);153 ASSERT_FALSE(EC);154 155 ASSERT_NO_ERROR(fs::rename(SourceFileName, TargetFileName));156 157#ifdef _WIN32158 // Make sure that target was temporarily renamed to target.tmp1 on Windows.159 // This is signified by a permission denied error as opposed to no such file160 // or directory when trying to open it.161 int Tmp1FD;162 EXPECT_EQ(errc::permission_denied,163 fs::openFileForRead(TargetTmp1FileName, Tmp1FD));164#endif165 }166 167 EXPECT_TRUE(FileHasContent(TargetTmp0FileName, "!!target.tmp0!!"));168 169 ASSERT_NO_ERROR(fs::remove(TargetFileName));170 ASSERT_NO_ERROR(fs::remove(TargetTmp0FileName));171 ASSERT_NO_ERROR(fs::remove(TestDirectory.str()));172}173 174} // anonymous namespace175