Patches item #1452698, was opened at 2006-03-17 20:08 Message generated for change (Comment added) made by gmsb You can respond by visiting: https://sourceforge.net/tracker/?func=detail&atid=307586&aid=1452698&group_id=7586 Please note that this message will contain a full copy of the comment thread, including the initial issue submission, for this request, not just the latest update. Category: None Group: None Status: Open Resolution: None Priority: 5 Private: No Submitted By: Nobody/Anonymous (nobody) Assigned to: Jonathan Turkanis (turkanis) Summary: iostreams // file_descriptor::seek BUG on files > 4 GB Initial Comment: Boost 1.33.1 iostreams library file_descriptor::seek() method file_descriptor.cpp, line 198 Win32, Visual C++ 2005 The method seek() can return a wrong value of a newly set offset when the offset is further than 4 GB. //--------------- return offset_to_position((lDistanceToMoveHigh << 32) + dwResultLow); //--------------- The code above has a bug. On 32-bit systems the expression (lDistanceToMoveHigh << 32) equals to lDistanceToMoveHigh. The correct code should first cast the lDistanceToMoveHigh variable to 64-bit and then shift it. //--------------- return (static_cast<boost::intmax_t> lDistanceToMoveHigh) << 32) + dwResultLow; //--------------- Sergey Kolodkin ---------------------------------------------------------------------- Comment By: Gareth Sylvester-Bradley (gmsb) Date: 2007-01-31 16:27 Message: Logged In: YES user_id=271167 Originator: NO There's also a bug 3 lines earlier. Windows GetLastError() shouldn't be checked unless dwResultLow is INVALID_SET_FILE_POINTER. Replace: 195 if (::GetLastError() != NO_ERROR) { 196 throw detail::bad_seek(); 197 } else { 198 return offset_to_position((lDistanceToMoveHigh << 32) + dwResultLow); 199 } 200 } With: 195 if (INVALID_SET_FILE_POINTER == dwResultLow && ::GetLastError() != NO_ERROR) { 196 throw detail::bad_seek(); 197 } else { 198 return offset_to_position((static_cast<stream_offset>(lDistanceToMoveHigh) << 32) + dwResultLow); 199 } 200 } ---------------------------------------------------------------------- You can respond by visiting: https://sourceforge.net/tracker/?func=detail&atid=307586&aid=1452698&group_id=7586 ------------------------------------------------------------------------- Take Surveys. Earn Cash. Influence the Future of IT Join SourceForge.net's Techsay panel and you'll get the chance to share your opinions on IT & business topics through brief surveys - and earn cash http://www.techsay.com/default.php?page=join.php&p=sourceforge&CID=DEVDEV _______________________________________________ Boost-bugs mailing list Boost-bugs@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/boost-bugs