blob: d2273d77f5ed3e6e6aa1da2660be137241221973 [file] [log] [blame]
//===- llvm/unittest/Support/ReplaceFileTest.cpp - unit tests -------------===//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
#include "llvm/Support/Errc.h"
#include "llvm/Support/ErrorHandling.h"
#include "llvm/Support/FileSystem.h"
#include "llvm/Support/MemoryBuffer.h"
#include "llvm/Support/Path.h"
#include "llvm/Support/Process.h"
#include "gtest/gtest.h"
using namespace llvm;
using namespace llvm::sys;
#define ASSERT_NO_ERROR(x) \
do { \
if (std::error_code ASSERT_NO_ERROR_ec = x) { \
errs() << #x ": did not return errc::success.\n" \
<< "error number: " << ASSERT_NO_ERROR_ec.value() << "\n" \
<< "error message: " << ASSERT_NO_ERROR_ec.message() << "\n"; \
} \
} while (false)
namespace {
std::error_code CreateFileWithContent(const SmallString<128> &FilePath,
const StringRef &content) {
int FD = 0;
if (std::error_code ec = fs::openFileForWrite(FilePath, FD))
return ec;
const bool ShouldClose = true;
raw_fd_ostream OS(FD, ShouldClose);
OS << content;
return std::error_code();
class ScopedFD {
int FD;
ScopedFD(const ScopedFD &) = delete;
ScopedFD &operator=(const ScopedFD &) = delete;
explicit ScopedFD(int Descriptor) : FD(Descriptor) {}
~ScopedFD() { Process::SafelyCloseFileDescriptor(FD); }
bool FDHasContent(int FD, StringRef Content) {
auto Buffer =
MemoryBuffer::getOpenFile(sys::fs::convertFDToNativeFile(FD), "", -1);
return Buffer.get()->getBuffer() == Content;
bool FileHasContent(StringRef File, StringRef Content) {
int FD = 0;
auto EC = fs::openFileForRead(File, FD);
ScopedFD EventuallyCloseIt(FD);
return FDHasContent(FD, Content);
TEST(rename, FileOpenedForReadingCanBeReplaced) {
// Create unique temporary directory for this test.
SmallString<128> TestDirectory;
"FileOpenedForReadingCanBeReplaced-test", TestDirectory));
// Add a couple of files to the test directory.
SmallString<128> SourceFileName(TestDirectory);
path::append(SourceFileName, "source");
SmallString<128> TargetFileName(TestDirectory);
path::append(TargetFileName, "target");
ASSERT_NO_ERROR(CreateFileWithContent(SourceFileName, "!!source!!"));
ASSERT_NO_ERROR(CreateFileWithContent(TargetFileName, "!!target!!"));
// Open the target file for reading.
int ReadFD = 0;
ASSERT_NO_ERROR(fs::openFileForRead(TargetFileName, ReadFD));
ScopedFD EventuallyCloseIt(ReadFD);
// Confirm we can replace the file while it is open.
EXPECT_TRUE(!fs::rename(SourceFileName, TargetFileName));
// We should still be able to read the old data through the existing
// descriptor.
EXPECT_TRUE(FDHasContent(ReadFD, "!!target!!"));
// The source file should no longer exist
// If we obtain a new descriptor for the target file, we should find that it
// contains the content that was in the source file.
EXPECT_TRUE(FileHasContent(TargetFileName, "!!source!!"));
// Rename the target file back to the source file name to confirm that rename
// still works if the destination does not already exist.
EXPECT_TRUE(!fs::rename(TargetFileName, SourceFileName));
// Clean up.
TEST(rename, ExistingTemp) {
// Test that existing .tmpN files don't get deleted by the Windows
// sys::fs::rename implementation.
SmallString<128> TestDirectory;
fs::createUniqueDirectory("ExistingTemp-test", TestDirectory));
SmallString<128> SourceFileName(TestDirectory);
path::append(SourceFileName, "source");
SmallString<128> TargetFileName(TestDirectory);
path::append(TargetFileName, "target");
SmallString<128> TargetTmp0FileName(TestDirectory);
path::append(TargetTmp0FileName, "target.tmp0");
SmallString<128> TargetTmp1FileName(TestDirectory);
path::append(TargetTmp1FileName, "target.tmp1");
ASSERT_NO_ERROR(CreateFileWithContent(SourceFileName, "!!source!!"));
ASSERT_NO_ERROR(CreateFileWithContent(TargetFileName, "!!target!!"));
ASSERT_NO_ERROR(CreateFileWithContent(TargetTmp0FileName, "!!target.tmp0!!"));
// Use mapped_file_region to make sure that the destination file is mmap'ed.
// This will cause SetInformationByHandle to fail when renaming to the
// destination, and we will follow the code path that tries to give target
// a temporary name.
int TargetFD;
std::error_code EC;
ASSERT_NO_ERROR(fs::openFileForRead(TargetFileName, TargetFD));
ScopedFD X(TargetFD);
sys::fs::mapped_file_region MFR(sys::fs::convertFDToNativeFile(TargetFD),
sys::fs::mapped_file_region::readonly, 10,
0, EC);
ASSERT_NO_ERROR(fs::rename(SourceFileName, TargetFileName));
#ifdef _WIN32
// Make sure that target was temporarily renamed to target.tmp1 on Windows.
// This is signified by a permission denied error as opposed to no such file
// or directory when trying to open it.
int Tmp1FD;
fs::openFileForRead(TargetTmp1FileName, Tmp1FD));
EXPECT_TRUE(FileHasContent(TargetTmp0FileName, "!!target.tmp0!!"));
} // anonymous namespace