libbcc/include/bcinfo/Wrap/file_wrapper_input.h

/*
 * Copyright 2012, The Android Open Source Project
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

// Defines utility allowing files for bitcode input wrapping.

#ifndef FILE_WRAPPER_INPUT_H__
#define FILE_WRAPPER_INPUT_H__

#include <stdio.h>

#include "bcinfo/Wrap/support_macros.h"
#include "bcinfo/Wrap/wrapper_input.h"

// Define a class to wrap named files.
class FileWrapperInput : public WrapperInput {
 public:
  explicit FileWrapperInput(const char* _name);
  ~FileWrapperInput();
  // Tries to read the requested number of bytes into the buffer. Returns the
  // actual number of bytes read.
  virtual size_t Read(uint8_t* buffer, size_t wanted);
  // Returns true if at end of file. Note: May return false
  // until Read is called, and returns 0.
  virtual bool AtEof();
  // Returns the size of the file (in bytes).
  virtual off_t Size();
  // Moves to the given offset within the file. Returns
  // false if unable to move to that position.
  virtual bool Seek(uint32_t pos);
 private:
  // The name of the file.
  const char* _name;
  // True once eof has been encountered.
  bool _at_eof;
  // True if size has been computed.
  bool _size_found;
  // The size of the file.
  off_t _size;
  // The corresponding (opened) file.
  FILE* _file;
 private:
  DISALLOW_CLASS_COPY_AND_ASSIGN(FileWrapperInput);
};

#endif // FILE_WRAPPER_INPUT_H__