Re: [PATCH 4/4] tracing/filters: Fix MATCH_EBD_ONLY filter matching

From: Li Zefan
Date: Sun Dec 13 2009 - 20:08:29 EST


>> static int regex_match_end(char *str, struct regex *r, int len)
>> {
>> - char *ptr = strstr(str, r->pattern);
>> + int strlen = len - 1;
>>
>> - if (ptr && (ptr[r->len] == 0))
>> + if (strlen >= r->len &&
>> + !memcmp(str + strlen - r->len, r->pattern, r->len))
>
> Please use memcmp() == 0, I've seen too many bugs with !*cmp as well as
> with *cmp, because humans tend to think instinctively when reading this
> that ! is not a match. With "== 0" we think that "==" is a match and
> "!=" is a miss.
>

Though I sometimes don't care much about this, I do
think memcmp() == 0 is better.

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