[core] fix computation of FAT size for Large FAT32

* Ridgecropt's GetFATSizeSectors() computation was incorrect
  and resulted in data sectors being "wasted" (unaddressable)
* See: http://www.syslinux.org/archives/2016-February/024850.html
* Also revert the minfatsize check of Syslinux, since it no longer fails.
This commit is contained in:
Pete Batard 2016-02-26 13:26:34 +00:00
parent ade5639c00
commit b9caf8b605
3 changed files with 13 additions and 24 deletions

View File

@ -347,31 +347,20 @@ static DWORD GetVolumeID(void)
} }
/* /*
* This is the Microsoft calculation from FATGEN * Proper computation of FAT size
* * See: http://www.syslinux.org/archives/2016-February/024850.html
* DWORD RootDirSectors = 0; * and subsequent replies.
* DWORD TmpVal1, TmpVal2, FATSz;
*
* TmpVal1 = DskSize - (ReservedSecCnt + RootDirSectors);
* TmpVal2 = (256 * SecPerClus) + NumFATs;
* TmpVal2 = TmpVal2 / 2;
* FATSz = (TmpVal1 + (TmpVal2 - 1)) / TmpVal2;
*
* return( FatSz );
*/ */
static DWORD GetFATSizeSectors(DWORD DskSize, DWORD ReservedSecCnt, DWORD SecPerClus, DWORD NumFATs, DWORD BytesPerSect) static DWORD GetFATSizeSectors(DWORD DskSize, DWORD ReservedSecCnt, DWORD SecPerClus, DWORD NumFATs, DWORD BytesPerSect)
{ {
ULONGLONG Numerator, Denominator; ULONGLONG Numerator, Denominator;
ULONGLONG FatElementSize = 4; ULONGLONG FatElementSize = 4;
ULONGLONG ReservedClusCnt = 2;
ULONGLONG FatSz; ULONGLONG FatSz;
// This is based on Numerator = DskSize - ReservedSecCnt + ReservedClusCnt * SecPerClus;
// http://hjem.get2net.dk/rune_moeller_barnkob/filesystems/fat.html Denominator = SecPerClus * BytesPerSect / FatElementSize + NumFATs;
Numerator = FatElementSize * (DskSize - ReservedSecCnt); FatSz = Numerator / Denominator + 1; // +1 to ensure we are rounded up
Denominator = (SecPerClus * BytesPerSect) + (FatElementSize * NumFATs);
FatSz = Numerator / Denominator;
// round up
FatSz += 1;
return (DWORD)FatSz; return (DWORD)FatSz;
} }

View File

@ -33,7 +33,7 @@ LANGUAGE LANG_NEUTRAL, SUBLANG_NEUTRAL
IDD_DIALOG DIALOGEX 12, 12, 242, 376 IDD_DIALOG DIALOGEX 12, 12, 242, 376
STYLE DS_SETFONT | DS_MODALFRAME | DS_CENTER | WS_MINIMIZEBOX | WS_POPUP | WS_CAPTION | WS_SYSMENU STYLE DS_SETFONT | DS_MODALFRAME | DS_CENTER | WS_MINIMIZEBOX | WS_POPUP | WS_CAPTION | WS_SYSMENU
EXSTYLE WS_EX_ACCEPTFILES EXSTYLE WS_EX_ACCEPTFILES
CAPTION "Rufus 2.8.868" CAPTION "Rufus 2.8.869"
FONT 8, "Segoe UI Symbol", 400, 0, 0x0 FONT 8, "Segoe UI Symbol", 400, 0, 0x0
BEGIN BEGIN
LTEXT "Device",IDS_DEVICE_TXT,9,6,200,8 LTEXT "Device",IDS_DEVICE_TXT,9,6,200,8
@ -320,8 +320,8 @@ END
// //
VS_VERSION_INFO VERSIONINFO VS_VERSION_INFO VERSIONINFO
FILEVERSION 2,8,868,0 FILEVERSION 2,8,869,0
PRODUCTVERSION 2,8,868,0 PRODUCTVERSION 2,8,869,0
FILEFLAGSMASK 0x3fL FILEFLAGSMASK 0x3fL
#ifdef _DEBUG #ifdef _DEBUG
FILEFLAGS 0x1L FILEFLAGS 0x1L
@ -338,13 +338,13 @@ BEGIN
BEGIN BEGIN
VALUE "CompanyName", "Akeo Consulting (http://akeo.ie)" VALUE "CompanyName", "Akeo Consulting (http://akeo.ie)"
VALUE "FileDescription", "Rufus" VALUE "FileDescription", "Rufus"
VALUE "FileVersion", "2.8.868" VALUE "FileVersion", "2.8.869"
VALUE "InternalName", "Rufus" VALUE "InternalName", "Rufus"
VALUE "LegalCopyright", "© 2011-2016 Pete Batard (GPL v3)" VALUE "LegalCopyright", "© 2011-2016 Pete Batard (GPL v3)"
VALUE "LegalTrademarks", "http://www.gnu.org/copyleft/gpl.html" VALUE "LegalTrademarks", "http://www.gnu.org/copyleft/gpl.html"
VALUE "OriginalFilename", "rufus.exe" VALUE "OriginalFilename", "rufus.exe"
VALUE "ProductName", "Rufus" VALUE "ProductName", "Rufus"
VALUE "ProductVersion", "2.8.868" VALUE "ProductVersion", "2.8.869"
END END
END END
BLOCK "VarFileInfo" BLOCK "VarFileInfo"

View File

@ -92,7 +92,7 @@ libfat_open(int (*readfunc) (intptr_t, void *, size_t, libfat_sector_t),
} else } else
goto barf; /* Impossibly many clusters */ goto barf; /* Impossibly many clusters */
minfatsize >>= LIBFAT_SECTOR_SHIFT; minfatsize = (minfatsize + LIBFAT_SECTOR_SIZE - 1) >> LIBFAT_SECTOR_SHIFT;
if (minfatsize > fatsize) if (minfatsize > fatsize)
goto barf; /* The FATs don't fit */ goto barf; /* The FATs don't fit */