Re: Long file names in VFAT broken with iocharset=utf8

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 

Hi!

On 7 May 2007, at 20:27, OGAWA Hirofumi wrote:


Roland Kuhn <[email protected]> writes:

PATH_MAX specifically counts _bytes_ not characters, so UTF-8 does
not matter. ISTR that PATH_MAX was 256 at some point, but I just
quickly grepped /usr/include and found various mention of 4096, so
where's the central repository for this configuration item? A hard-
coded value of 256 somewhere inside the kernel smells like a bug.
There is a nasty issue here. FAT is limited by 255 unicode chars or so. 
So, we would need to count number of unicode chars of filename.
No, we don't. At least not when looking at the POSIX spec, which explicitly mentions _bytes_ and _not_ unicode characters. So, to be on the safe side, FAT filesystems would need to support a NAME_MAX of roughly 6*255+3=1533 bytes (not to mention the hassles of forbidden sequences, etc.; do we need to count zero-width characters?) and report it through pathconf() to userspace, then userspace could do with that whatever it liked.
What happened to: "file names are just sequences of octets, excluding '/' and NUL"? Adding unicode parsing to the kernel is completely useless _and_ a big trouble maker. 

Ciao,
                    Roland

--
TU Muenchen, Physik-Department E18, James-Franck-Str., 85748 Garching
Telefon 089/289-12575; Telefax 089/289-12570
--
CERN office: 892-1-D23 phone: +41 22 7676540 mobile: +41 76 487 4482
--
Any society that would give up a little liberty to gain a little
security will deserve neither and lose both.  - Benjamin Franklin
-----BEGIN GEEK CODE BLOCK-----
Version: 3.12
GS/CS/M/MU d-(++) s:+ a-> C+++ UL++++ P+++ L+++ E(+) W+ !N K- w--- M + !V Y+ 
PGP++ t+(++) 5 R+ tv-- b+ DI++ e+++>++++ h---- y+++
------END GEEK CODE BLOCK------

Attachment: smime.p7s
Description: S/MIME cryptographic signature

Attachment: PGP.sig
Description: This is a digitally signed message part

[Index of Archives]     [Kernel Newbies]     [Netfilter]     [Bugtraq]     [Photo]     [Stuff]     [Gimp]     [Yosemite News]     [MIPS Linux]     [ARM Linux]     [Linux Security]     [Linux RAID]     [Video 4 Linux]     [Linux for the blind]     [Linux Resources]
  Powered by Linux