| //=== FileOutputBuffer.h - File Output Buffer -------------------*- C++ -*-===// |
| // |
| // The LLVM Compiler Infrastructure |
| // |
| // This file is distributed under the University of Illinois Open Source |
| // License. See LICENSE.TXT for details. |
| // |
| //===----------------------------------------------------------------------===// |
| // |
| // Utility for creating a in-memory buffer that will be written to a file. |
| // |
| //===----------------------------------------------------------------------===// |
| |
| #ifndef LLVM_SUPPORT_FILEOUTPUTBUFFER_H |
| #define LLVM_SUPPORT_FILEOUTPUTBUFFER_H |
| |
| #include "llvm/ADT/SmallString.h" |
| #include "llvm/ADT/StringRef.h" |
| #include "llvm/Support/DataTypes.h" |
| #include "llvm/Support/ErrorOr.h" |
| #include "llvm/Support/FileSystem.h" |
| |
| namespace llvm { |
| /// FileOutputBuffer - This interface provides simple way to create an in-memory |
| /// buffer which will be written to a file. During the lifetime of these |
| /// objects, the content or existence of the specified file is undefined. That |
| /// is, creating an OutputBuffer for a file may immediately remove the file. |
| /// If the FileOutputBuffer is committed, the target file's content will become |
| /// the buffer content at the time of the commit. If the FileOutputBuffer is |
| /// not committed, the file will be deleted in the FileOutputBuffer destructor. |
| class FileOutputBuffer { |
| public: |
| |
| enum { |
| F_executable = 1 /// set the 'x' bit on the resulting file |
| }; |
| |
| /// Factory method to create an OutputBuffer object which manages a read/write |
| /// buffer of the specified size. When committed, the buffer will be written |
| /// to the file at the specified path. |
| static ErrorOr<std::unique_ptr<FileOutputBuffer>> |
| create(StringRef FilePath, size_t Size, unsigned Flags = 0); |
| |
| /// Returns a pointer to the start of the buffer. |
| uint8_t *getBufferStart() { |
| return (uint8_t*)Region->data(); |
| } |
| |
| /// Returns a pointer to the end of the buffer. |
| uint8_t *getBufferEnd() { |
| return (uint8_t*)Region->data() + Region->size(); |
| } |
| |
| /// Returns size of the buffer. |
| size_t getBufferSize() const { |
| return Region->size(); |
| } |
| |
| /// Returns path where file will show up if buffer is committed. |
| StringRef getPath() const { |
| return FinalPath; |
| } |
| |
| /// Flushes the content of the buffer to its file and deallocates the |
| /// buffer. If commit() is not called before this object's destructor |
| /// is called, the file is deleted in the destructor. The optional parameter |
| /// is used if it turns out you want the file size to be smaller than |
| /// initially requested. |
| std::error_code commit(); |
| |
| /// If this object was previously committed, the destructor just deletes |
| /// this object. If this object was not committed, the destructor |
| /// deallocates the buffer and the target file is never written. |
| ~FileOutputBuffer(); |
| |
| private: |
| FileOutputBuffer(const FileOutputBuffer &) = delete; |
| FileOutputBuffer &operator=(const FileOutputBuffer &) = delete; |
| |
| FileOutputBuffer(std::unique_ptr<llvm::sys::fs::mapped_file_region> R, |
| StringRef Path, StringRef TempPath, bool IsRegular); |
| |
| std::unique_ptr<llvm::sys::fs::mapped_file_region> Region; |
| SmallString<128> FinalPath; |
| SmallString<128> TempPath; |
| bool IsRegular; |
| }; |
| } // end namespace llvm |
| |
| #endif |