From 0b57cec536236d46e3dba9bd041533462f33dbb7 Mon Sep 17 00:00:00 2001 From: Dimitry Andric Date: Fri, 20 Dec 2019 19:53:05 +0000 Subject: Move all sources from the llvm project into contrib/llvm-project. This uses the new layout of the upstream repository, which was recently migrated to GitHub, and converted into a "monorepo". That is, most of the earlier separate sub-projects with their own branches and tags were consolidated into one top-level directory, and are now branched and tagged together. Updating the vendor area to match this layout is next. --- contrib/llvm/lib/Support/FileOutputBuffer.cpp | 196 -------------------------- 1 file changed, 196 deletions(-) delete mode 100644 contrib/llvm/lib/Support/FileOutputBuffer.cpp (limited to 'contrib/llvm/lib/Support/FileOutputBuffer.cpp') diff --git a/contrib/llvm/lib/Support/FileOutputBuffer.cpp b/contrib/llvm/lib/Support/FileOutputBuffer.cpp deleted file mode 100644 index 3d6b569f2993..000000000000 --- a/contrib/llvm/lib/Support/FileOutputBuffer.cpp +++ /dev/null @@ -1,196 +0,0 @@ -//===- FileOutputBuffer.cpp - File Output Buffer ----------------*- C++ -*-===// -// -// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. -// See https://llvm.org/LICENSE.txt for license information. -// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception -// -//===----------------------------------------------------------------------===// -// -// Utility for creating a in-memory buffer that will be written to a file. -// -//===----------------------------------------------------------------------===// - -#include "llvm/Support/FileOutputBuffer.h" -#include "llvm/ADT/STLExtras.h" -#include "llvm/ADT/SmallString.h" -#include "llvm/Support/Errc.h" -#include "llvm/Support/Memory.h" -#include "llvm/Support/Path.h" -#include - -#if !defined(_MSC_VER) && !defined(__MINGW32__) -#include -#else -#include -#endif - -using namespace llvm; -using namespace llvm::sys; - -namespace { -// A FileOutputBuffer which creates a temporary file in the same directory -// as the final output file. The final output file is atomically replaced -// with the temporary file on commit(). -class OnDiskBuffer : public FileOutputBuffer { -public: - OnDiskBuffer(StringRef Path, fs::TempFile Temp, - std::unique_ptr Buf) - : FileOutputBuffer(Path), Buffer(std::move(Buf)), Temp(std::move(Temp)) {} - - uint8_t *getBufferStart() const override { return (uint8_t *)Buffer->data(); } - - uint8_t *getBufferEnd() const override { - return (uint8_t *)Buffer->data() + Buffer->size(); - } - - size_t getBufferSize() const override { return Buffer->size(); } - - Error commit() override { - // Unmap buffer, letting OS flush dirty pages to file on disk. - Buffer.reset(); - - // Atomically replace the existing file with the new one. - return Temp.keep(FinalPath); - } - - ~OnDiskBuffer() override { - // Close the mapping before deleting the temp file, so that the removal - // succeeds. - Buffer.reset(); - consumeError(Temp.discard()); - } - - void discard() override { - // Delete the temp file if it still was open, but keeping the mapping - // active. - consumeError(Temp.discard()); - } - -private: - std::unique_ptr Buffer; - fs::TempFile Temp; -}; - -// A FileOutputBuffer which keeps data in memory and writes to the final -// output file on commit(). This is used only when we cannot use OnDiskBuffer. -class InMemoryBuffer : public FileOutputBuffer { -public: - InMemoryBuffer(StringRef Path, MemoryBlock Buf, std::size_t BufSize, - unsigned Mode) - : FileOutputBuffer(Path), Buffer(Buf), BufferSize(BufSize), - Mode(Mode) {} - - uint8_t *getBufferStart() const override { return (uint8_t *)Buffer.base(); } - - uint8_t *getBufferEnd() const override { - return (uint8_t *)Buffer.base() + BufferSize; - } - - size_t getBufferSize() const override { return BufferSize; } - - Error commit() override { - if (FinalPath == "-") { - llvm::outs() << StringRef((const char *)Buffer.base(), BufferSize); - llvm::outs().flush(); - return Error::success(); - } - - using namespace sys::fs; - int FD; - std::error_code EC; - if (auto EC = - openFileForWrite(FinalPath, FD, CD_CreateAlways, OF_None, Mode)) - return errorCodeToError(EC); - raw_fd_ostream OS(FD, /*shouldClose=*/true, /*unbuffered=*/true); - OS << StringRef((const char *)Buffer.base(), BufferSize); - return Error::success(); - } - -private: - // Buffer may actually contain a larger memory block than BufferSize - OwningMemoryBlock Buffer; - size_t BufferSize; - unsigned Mode; -}; -} // namespace - -static Expected> -createInMemoryBuffer(StringRef Path, size_t Size, unsigned Mode) { - std::error_code EC; - MemoryBlock MB = Memory::allocateMappedMemory( - Size, nullptr, sys::Memory::MF_READ | sys::Memory::MF_WRITE, EC); - if (EC) - return errorCodeToError(EC); - return llvm::make_unique(Path, MB, Size, Mode); -} - -static Expected> -createOnDiskBuffer(StringRef Path, size_t Size, unsigned Mode) { - Expected FileOrErr = - fs::TempFile::create(Path + ".tmp%%%%%%%", Mode); - if (!FileOrErr) - return FileOrErr.takeError(); - fs::TempFile File = std::move(*FileOrErr); - -#ifndef _WIN32 - // On Windows, CreateFileMapping (the mmap function on Windows) - // automatically extends the underlying file. We don't need to - // extend the file beforehand. _chsize (ftruncate on Windows) is - // pretty slow just like it writes specified amount of bytes, - // so we should avoid calling that function. - if (auto EC = fs::resize_file(File.FD, Size)) { - consumeError(File.discard()); - return errorCodeToError(EC); - } -#endif - - // Mmap it. - std::error_code EC; - auto MappedFile = llvm::make_unique( - fs::convertFDToNativeFile(File.FD), fs::mapped_file_region::readwrite, - Size, 0, EC); - - // mmap(2) can fail if the underlying filesystem does not support it. - // If that happens, we fall back to in-memory buffer as the last resort. - if (EC) { - consumeError(File.discard()); - return createInMemoryBuffer(Path, Size, Mode); - } - - return llvm::make_unique(Path, std::move(File), - std::move(MappedFile)); -} - -// Create an instance of FileOutputBuffer. -Expected> -FileOutputBuffer::create(StringRef Path, size_t Size, unsigned Flags) { - // Handle "-" as stdout just like llvm::raw_ostream does. - if (Path == "-") - return createInMemoryBuffer("-", Size, /*Mode=*/0); - - unsigned Mode = fs::all_read | fs::all_write; - if (Flags & F_executable) - Mode |= fs::all_exe; - - fs::file_status Stat; - fs::status(Path, Stat); - - // Usually, we want to create OnDiskBuffer to create a temporary file in - // the same directory as the destination file and atomically replaces it - // by rename(2). - // - // However, if the destination file is a special file, we don't want to - // use rename (e.g. we don't want to replace /dev/null with a regular - // file.) If that's the case, we create an in-memory buffer, open the - // destination file and write to it on commit(). - switch (Stat.type()) { - case fs::file_type::directory_file: - return errorCodeToError(errc::is_a_directory); - case fs::file_type::regular_file: - case fs::file_type::file_not_found: - case fs::file_type::status_error: - return createOnDiskBuffer(Path, Size, Mode); - default: - return createInMemoryBuffer(Path, Size, Mode); - } -} -- cgit v1.2.3