google-breakpad/src/common/linux/file_id.h

// Copyright (c) 2006, Google Inc.
// All rights reserved.
//
// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions are
// met:
//
//     * Redistributions of source code must retain the above copyright
// notice, this list of conditions and the following disclaimer.
//     * Redistributions in binary form must reproduce the above
// copyright notice, this list of conditions and the following disclaimer
// in the documentation and/or other materials provided with the
// distribution.
//     * Neither the name of Google Inc. nor the names of its
// contributors may be used to endorse or promote products derived from
// this software without specific prior written permission.
//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
//
// file_id.h: Return a unique identifier for a file
//

#ifndef COMMON_LINUX_FILE_ID_H__
#define COMMON_LINUX_FILE_ID_H__

#include <limits.h>
#include <string>

#include "common/linux/guid_creator.h"

namespace google_breakpad {

static const size_t kMDGUIDSize = sizeof(MDGUID);

class FileID {
 public:
  explicit FileID(const char* path);
  ~FileID() {}

  // Load the identifier for the elf file path specified in the constructor into
  // |identifier|.  Return false if the identifier could not be created for the
  // file.
  // The current implementation will look for a .note.gnu.build-id
  // section and use that as the file id, otherwise it falls back to
  // XORing the first 4096 bytes of the .text section to generate an identifier.
  bool ElfFileIdentifier(uint8_t identifier[kMDGUIDSize]);

  // Load the identifier for the elf file mapped into memory at |base| into
  // |identifier|.  Return false if the identifier could not be created for the
  // file.
  static bool ElfFileIdentifierFromMappedFile(const void* base,
                                              uint8_t identifier[kMDGUIDSize]);

  // Convert the |identifier| data to a NULL terminated string.  The string will
  // be formatted as a UUID (e.g., 22F065BB-FC9C-49F7-80FE-26A7CEBD7BCE).
  // The |buffer| should be at least 37 bytes long to receive all of the data
  // and termination.  Shorter buffers will contain truncated data.
  static void ConvertIdentifierToString(const uint8_t identifier[kMDGUIDSize],
                                        char* buffer, int buffer_length);

 private:
  // Storage for the path specified
  std::string path_;
};

}  // namespace google_breakpad

#endif  // COMMON_LINUX_FILE_ID_H__