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// **************************************************************************
// * This file is part of the FreeFileSync project. It is distributed under *
// * GNU General Public License: http://www.gnu.org/licenses/gpl.html *
// * Copyright (C) 2008-2011 ZenJu (zhnmju123 AT gmx.de) *
// **************************************************************************
//
#include "file_id.h"
#ifdef FFS_WIN
#include <wx/msw/wrapwin.h> //includes "windows.h"
#include "long_path_prefix.h"
#include "loki/ScopeGuard.h"
#elif defined FFS_LINUX
#include <sys/stat.h>
#endif
namespace
{
template <class T>
inline
std::string numberToBytes(T number)
{
const char* rawBegin = reinterpret_cast<const char*>(&number);
return std::string(rawBegin, rawBegin + sizeof(number));
}
}
std::string util::retrieveFileID(const Zstring& filename)
{
std::string fileID;
#ifdef FFS_WIN
//WARNING: CreateFile() is SLOW, while GetFileInformationByHandle() is cheap!
//http://msdn.microsoft.com/en-us/library/aa363788(VS.85).aspx
//privilege SE_BACKUP_NAME doesn't seem to be required here at all
const HANDLE hFile = ::CreateFile(zen::applyLongPathPrefix(filename).c_str(),
0,
FILE_SHARE_READ | FILE_SHARE_WRITE | FILE_SHARE_DELETE,
NULL,
OPEN_EXISTING,
FILE_FLAG_OPEN_REPARSE_POINT | FILE_FLAG_BACKUP_SEMANTICS, //FILE_FLAG_BACKUP_SEMANTICS needed to open a directory
NULL);
if (hFile != INVALID_HANDLE_VALUE)
{
Loki::ScopeGuard dummy = Loki::MakeGuard(::CloseHandle, hFile);
(void)dummy; //silence warning "unused variable"
BY_HANDLE_FILE_INFORMATION fileInfo = {};
if (::GetFileInformationByHandle(hFile, &fileInfo))
{
fileID += numberToBytes(fileInfo.dwVolumeSerialNumber);
fileID += numberToBytes(fileInfo.nFileIndexHigh);
fileID += numberToBytes(fileInfo.nFileIndexLow);
}
}
#elif defined FFS_LINUX
struct stat fileInfo = {};
if (::lstat(filename.c_str(), &fileInfo) == 0) //lstat() does not follow symlinks
{
fileID += numberToBytes(fileInfo.st_dev);
fileID += numberToBytes(fileInfo.st_ino);
}
#endif
assert(!fileID.empty());
return fileID;
}
bool util::sameFileSpecified(const Zstring& file1, const Zstring& file2)
{
if (EqualFilename()(file1, file2)) //quick check
return true;
const std::string id1 = retrieveFileID(file1);
const std::string id2 = retrieveFileID(file2);
if (id1.empty() || id2.empty())
return false;
return id1 == id2;
}
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