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

[Roland Kuhn]

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.

So, we would need to count number of unicode chars of filename.

There is a nasty issue here. FAT is limited by 255 unicode chars or so.

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.

Ciao,
                    Roland

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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. GS/CS/M/MU d-(++) s:+ a-> C+++ UL++++ P+++ L+++ E(+) W+ !N K- w--- M + !V Y+

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