MemoryBuffer.cpp | Explore in Territory

//===--- MemoryBuffer.cpp - Memory Buffer implementation ------------------===//
//
// 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
//
//===----------------------------------------------------------------------===//
//
//  This file implements the MemoryBuffer interface.
//
//===----------------------------------------------------------------------===//

#include "llvm/Support/MemoryBuffer.h"
#include "llvm/ADT/STLExtras.h"
#include "llvm/ADT/SmallString.h"
#include "llvm/Config/config.h"
#include "llvm/Support/Alignment.h"
#include "llvm/Support/Errc.h"
#include "llvm/Support/Error.h"
#include "llvm/Support/ErrorHandling.h"
#include "llvm/Support/FileSystem.h"
#include "llvm/Support/MathExtras.h"
#include "llvm/Support/Process.h"
#include "llvm/Support/Program.h"
#include "llvm/Support/SmallVectorMemoryBuffer.h"
#include <algorithm>
#include <cassert>
#include <cstring>
#include <new>
#include <sys/types.h>
#include <system_error>
#if !defined(_MSC_VER) && !defined(__MINGW32__)
#include <unistd.h>
#else
#include <io.h>
#endif

#ifdef __MVS__
#include "llvm/Support/AutoConvert.h"
#endif
usingnamespacellvm;

//===----------------------------------------------------------------------===//
// MemoryBuffer implementation itself.
//===----------------------------------------------------------------------===//

MemoryBuffer::~MemoryBuffer() = default;

/// init - Initialize this MemoryBuffer as a reference to externally allocated
/// memory, memory that we know is already null terminated.
void MemoryBuffer::init(const char *BufStart, const char *BufEnd,
                        bool RequiresNullTerminator) { … }

//===----------------------------------------------------------------------===//
// MemoryBufferMem implementation.
//===----------------------------------------------------------------------===//

/// CopyStringRef - Copies contents of a StringRef into a block of memory and
/// null-terminates it.
static void CopyStringRef(char *Memory, StringRef Data) { … }

namespace {
struct NamedBufferAlloc { … };
} // namespace

void *operator new(size_t N, const NamedBufferAlloc &Alloc) { … }

namespace {
/// MemoryBufferMem - Named MemoryBuffer pointing to a block of memory.
template<typename MB>
class MemoryBufferMem : public MB { … };
} // namespace

template <typename MB>
static ErrorOr<std::unique_ptr<MB>>
getFileAux(const Twine &Filename, uint64_t MapSize, uint64_t Offset,
           bool IsText, bool RequiresNullTerminator, bool IsVolatile,
           std::optional<Align> Alignment);

std::unique_ptr<MemoryBuffer>
MemoryBuffer::getMemBuffer(StringRef InputData, StringRef BufferName,
                           bool RequiresNullTerminator) { … }

std::unique_ptr<MemoryBuffer>
MemoryBuffer::getMemBuffer(MemoryBufferRef Ref, bool RequiresNullTerminator) { … }

static ErrorOr<std::unique_ptr<WritableMemoryBuffer>>
getMemBufferCopyImpl(StringRef InputData, const Twine &BufferName) { … }

std::unique_ptr<MemoryBuffer>
MemoryBuffer::getMemBufferCopy(StringRef InputData, const Twine &BufferName) { … }

ErrorOr<std::unique_ptr<MemoryBuffer>>
MemoryBuffer::getFileOrSTDIN(const Twine &Filename, bool IsText,
                             bool RequiresNullTerminator,
                             std::optional<Align> Alignment) { … }

ErrorOr<std::unique_ptr<MemoryBuffer>>
MemoryBuffer::getFileSlice(const Twine &FilePath, uint64_t MapSize,
                           uint64_t Offset, bool IsVolatile,
                           std::optional<Align> Alignment) { … }

//===----------------------------------------------------------------------===//
// MemoryBuffer::getFile implementation.
//===----------------------------------------------------------------------===//

namespace {

Mapmode;
Mapmode;
Mapmode;
Mapmode;

/// Memory maps a file descriptor using sys::fs::mapped_file_region.
///
/// This handles converting the offset into a legal offset on the platform.
template<typename MB>
class MemoryBufferMMapFile : public MB { … };
} // namespace

static ErrorOr<std::unique_ptr<WritableMemoryBuffer>>
getMemoryBufferForStream(sys::fs::file_t FD, const Twine &BufferName) { … }

ErrorOr<std::unique_ptr<MemoryBuffer>>
MemoryBuffer::getFile(const Twine &Filename, bool IsText,
                      bool RequiresNullTerminator, bool IsVolatile,
                      std::optional<Align> Alignment) { … }

template <typename MB>
static ErrorOr<std::unique_ptr<MB>>
getOpenFileImpl(sys::fs::file_t FD, const Twine &Filename, uint64_t FileSize,
                uint64_t MapSize, int64_t Offset, bool RequiresNullTerminator,
                bool IsVolatile, std::optional<Align> Alignment);

template <typename MB>
static ErrorOr<std::unique_ptr<MB>>
getFileAux(const Twine &Filename, uint64_t MapSize, uint64_t Offset,
           bool IsText, bool RequiresNullTerminator, bool IsVolatile,
           std::optional<Align> Alignment) { … }

ErrorOr<std::unique_ptr<WritableMemoryBuffer>>
WritableMemoryBuffer::getFile(const Twine &Filename, bool IsVolatile,
                              std::optional<Align> Alignment) { … }

ErrorOr<std::unique_ptr<WritableMemoryBuffer>>
WritableMemoryBuffer::getFileSlice(const Twine &Filename, uint64_t MapSize,
                                   uint64_t Offset, bool IsVolatile,
                                   std::optional<Align> Alignment) { … }

std::unique_ptr<WritableMemoryBuffer>
WritableMemoryBuffer::getNewUninitMemBuffer(size_t Size,
                                            const Twine &BufferName,
                                            std::optional<Align> Alignment) { … }

std::unique_ptr<WritableMemoryBuffer>
WritableMemoryBuffer::getNewMemBuffer(size_t Size, const Twine &BufferName) { … }

static bool shouldUseMmap(sys::fs::file_t FD,
                          size_t FileSize,
                          size_t MapSize,
                          off_t Offset,
                          bool RequiresNullTerminator,
                          int PageSize,
                          bool IsVolatile) { … }

static ErrorOr<std::unique_ptr<WriteThroughMemoryBuffer>>
getReadWriteFile(const Twine &Filename, uint64_t FileSize, uint64_t MapSize,
                 uint64_t Offset) { … }

ErrorOr<std::unique_ptr<WriteThroughMemoryBuffer>>
WriteThroughMemoryBuffer::getFile(const Twine &Filename, int64_t FileSize) { … }

/// Map a subrange of the specified file as a WritableMemoryBuffer.
ErrorOr<std::unique_ptr<WriteThroughMemoryBuffer>>
WriteThroughMemoryBuffer::getFileSlice(const Twine &Filename, uint64_t MapSize,
                                       uint64_t Offset) { … }

template <typename MB>
static ErrorOr<std::unique_ptr<MB>>
getOpenFileImpl(sys::fs::file_t FD, const Twine &Filename, uint64_t FileSize,
                uint64_t MapSize, int64_t Offset, bool RequiresNullTerminator,
                bool IsVolatile, std::optional<Align> Alignment) { … }

ErrorOr<std::unique_ptr<MemoryBuffer>>
MemoryBuffer::getOpenFile(sys::fs::file_t FD, const Twine &Filename,
                          uint64_t FileSize, bool RequiresNullTerminator,
                          bool IsVolatile, std::optional<Align> Alignment) { … }

ErrorOr<std::unique_ptr<MemoryBuffer>> MemoryBuffer::getOpenFileSlice(
    sys::fs::file_t FD, const Twine &Filename, uint64_t MapSize, int64_t Offset,
    bool IsVolatile, std::optional<Align> Alignment) { … }

ErrorOr<std::unique_ptr<MemoryBuffer>> MemoryBuffer::getSTDIN() { … }

ErrorOr<std::unique_ptr<MemoryBuffer>>
MemoryBuffer::getFileAsStream(const Twine &Filename) { … }

MemoryBufferRef MemoryBuffer::getMemBufferRef() const { … }

SmallVectorMemoryBuffer::~SmallVectorMemoryBuffer() = default;
llvm/llvm/lib/Support/MemoryBuffer.cpp
