Coverage Report

Created: 2019-07-24 05:18

/Users/buildslave/jenkins/workspace/clang-stage2-coverage-R/llvm/include/llvm/Support/FileOutputBuffer.h
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//=== FileOutputBuffer.h - File Output Buffer -------------------*- C++ -*-===//
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//
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// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
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// See https://llvm.org/LICENSE.txt for license information.
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// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
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//
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//===----------------------------------------------------------------------===//
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//
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// Utility for creating a in-memory buffer that will be written to a file.
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//
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//===----------------------------------------------------------------------===//
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#ifndef LLVM_SUPPORT_FILEOUTPUTBUFFER_H
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#define LLVM_SUPPORT_FILEOUTPUTBUFFER_H
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#include "llvm/ADT/SmallString.h"
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#include "llvm/ADT/StringRef.h"
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#include "llvm/Support/DataTypes.h"
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#include "llvm/Support/Error.h"
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#include "llvm/Support/FileSystem.h"
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namespace llvm {
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/// FileOutputBuffer - This interface provides simple way to create an in-memory
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/// buffer which will be written to a file. During the lifetime of these
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/// objects, the content or existence of the specified file is undefined. That
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/// is, creating an OutputBuffer for a file may immediately remove the file.
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/// If the FileOutputBuffer is committed, the target file's content will become
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/// the buffer content at the time of the commit.  If the FileOutputBuffer is
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/// not committed, the file will be deleted in the FileOutputBuffer destructor.
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class FileOutputBuffer {
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public:
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  enum {
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    /// set the 'x' bit on the resulting file
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    F_executable = 1,
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  };
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  /// Factory method to create an OutputBuffer object which manages a read/write
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  /// buffer of the specified size. When committed, the buffer will be written
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  /// to the file at the specified path.
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  ///
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  /// When F_modify is specified and \p FilePath refers to an existing on-disk
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  /// file \p Size may be set to -1, in which case the entire file is used.
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  /// Otherwise, the file shrinks or grows as necessary based on the value of
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  /// \p Size.  It is an error to specify F_modify and Size=-1 if \p FilePath
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  /// does not exist.
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  static Expected<std::unique_ptr<FileOutputBuffer>>
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  create(StringRef FilePath, size_t Size, unsigned Flags = 0);
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  /// Returns a pointer to the start of the buffer.
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  virtual uint8_t *getBufferStart() const = 0;
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  /// Returns a pointer to the end of the buffer.
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  virtual uint8_t *getBufferEnd() const = 0;
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  /// Returns size of the buffer.
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  virtual size_t getBufferSize() const = 0;
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  /// Returns path where file will show up if buffer is committed.
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0
  StringRef getPath() const { return FinalPath; }
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  /// Flushes the content of the buffer to its file and deallocates the
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  /// buffer.  If commit() is not called before this object's destructor
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  /// is called, the file is deleted in the destructor. The optional parameter
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  /// is used if it turns out you want the file size to be smaller than
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  /// initially requested.
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  virtual Error commit() = 0;
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  /// If this object was previously committed, the destructor just deletes
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  /// this object.  If this object was not committed, the destructor
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  /// deallocates the buffer and the target file is never written.
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  virtual ~FileOutputBuffer() {}
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  /// This removes the temporary file (unless it already was committed)
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  /// but keeps the memory mapping alive.
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  virtual void discard() {}
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protected:
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  FileOutputBuffer(StringRef Path) : FinalPath(Path) {}
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  std::string FinalPath;
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};
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} // end namespace llvm
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#endif