lkml.org 
[lkml]   [2007]   [Jun]   [26]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
Date
From
SubjectRe: [patch 1/2] HFS+: Refactor ASCII to unicode conversion routine for later reuse
On 25/06/07, Roman Zippel <zippel@linux-m68k.org> wrote:
>
> I like the idea of this, but not that it generates larger code, so I
> reformatted it a little to get rid of the decomposed_uc struct which
> required an unnecessary data copy, so now the it even generates slightly
> smaller code. :)

Ah, nice one! Returning the pointer into the table is a much nicer way
of doing things.

> + if (decompose && (dstr = decompose_unichar(c, &dsize))) {
> + if (outlen + dsize > HFSPLUS_MAX_STRLEN)
> break;
> do {
> - ustr->unicode[outlen++] = cpu_to_be16(hfsplus_decompose_table[off++]);
> - } while (--size > 0);
> - continue;
> - }
> - done:
> - ustr->unicode[outlen++] = cpu_to_be16(c);
> + ustr->unicode[outlen++] = cpu_to_be16(*dstr++);
> + } while (--dsize > 0);

Andrew's comments about the loop in the second patch apply here too, I
think. The original code did have a check for this condition, so I
guess it is a potential problem. How about this (on top of your
version of the patches):

Index: linux-2.6.21.5/fs/hfsplus/unicode.c
===================================================================
--- linux-2.6.21.5.orig/fs/hfsplus/unicode.c
+++ linux-2.6.21.5/fs/hfsplus/unicode.c
@@ -280,7 +280,9 @@ static inline u16 *decompose_unichar(wch
return NULL;

off = hfsplus_decompose_table[off + (uc & 0xf)];
- *size = off & 3;
+ if ((*size = off & 3) == 0)
+ return NULL;
+
return hfsplus_decompose_table + (off / 4);
}

I'm using gmail to send this, so it will mess up the tabs I'm afraid :(
> bye, Roman

Cheers,
Duane.

--
"I never could learn to drink that blood and call it wine" - Bob Dylan
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/

\
 
 \ /
  Last update: 2007-06-26 12:05    [W:0.061 / U:0.196 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site