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Re: [PATCH 3/4] diffcore-pickaxe: further refactor count_match()

From
Junio C Hamano <gitster@pobox.com>
Date
Feb 28, 2009, 01:25 UTC
Message-ID
<7vy6vrgxnn.fsf@gitster.siamese.dyndns.org>
In-Reply-To
<49A88FA7.1020402@lsrfire.ath.cx>
René Scharfe <rene.scharfe@lsrfire.ath.cx> writes:
Show 11 quoted lines
>> -
>> -	} else { /* Classic exact string match */
>> -		/* Yes, I've heard of strstr(), but the thing is *data may
>> -		 * not be NUL terminated.  Sue me.
>> -		 */
>> +	} else {
>> +		/* data many not be NUL terminated; we cannot use strstr() */
>
> That looks fishy to me.  regexec() expects data to be a NUL-terminated
> string, so either the comment is wrong or the regexp case needs to take
> better care to add a NUL at the end of the buffer.
Probably yes, but regexp side is not my code and I never use it, so... ;-)
> In any case, there is also memmem(), which uses the same fast algorithm
> as strstr() in recent glibc versions.  Like this?
Thanks; it would be nice to bench this change.
Previous: René ScharfeNext: Junio C Hamano
Message 8 of 23 in “Pickaxe search clean-up and optimization”
  1. 0/4 Pickaxe search clean-up and optimizationJunio C Hamano, Feb 26, 2009
  2. 1/4 diffcore-pickaxe: refactor diffcore_pickaxe()Junio C Hamano, Feb 26, 2009
  3. René ScharfeFeb 27, 2009
  4. 2/4 diffcore-pickaxe: micro-optimize has_match() functionJunio C Hamano, Feb 26, 2009
  5. 3/4 diffcore-pickaxe: further refactor count_match()Junio C Hamano, Feb 26, 2009
  6. Kjetil BarvikFeb 26, 2009
  7. René ScharfeFeb 28, 2009
  8. Junio C HamanoFeb 28, 2009
  9. Junio C HamanoFeb 28, 2009
  10. René ScharfeFeb 28, 2009
  11. Junio C HamanoFeb 28, 2009
  12. René ScharfeFeb 28, 2009
  13. import memmem() with linear complexity from GnulibRené Scharfe, Feb 28, 2009
  14. Mike HommeyFeb 28, 2009
  15. Jeff KingMar 1, 2009
  16. René ScharfeMar 1, 2009
  17. René ScharfeMar 1, 2009
  18. Junio C HamanoMar 1, 2009
  19. René ScharfeMar 1, 2009
  20. 4/4 diffcore-pickaxe: optimize by trimming common initial and trailing partsJunio C Hamano, Feb 26, 2009
  21. Junio C HamanoFeb 26, 2009
  22. 1/2 diffcore-pickaxe: use memmem()René Scharfe, Mar 2, 2009
  23. 2/2 optimize compat/ memmem()René Scharfe, Mar 2, 2009

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