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Tom Lane wrote:
Andrew Dunstan <[EMAIL PROTECTED]> writes:
OK, here is a patch that I think incorporates all the ideas discussed
(including part of Mark Mielke's suggestion about optimising %_). There
is now no special treatment of UTF8 other than its use of a faster
NextChar macro.
Looks mostly pretty good. I would suggest replacing tests "tlen == 0"
and "plen == 0" with "<= 0", just so the code doesn't go completely
insane if presented with invalidly-encoded data that causes it to step
beyond the end of data. Also, this comment is not really good enough:
! /*
! * It is safe to use NextByte instead of NextChar here, even for
! * multi-byte character sets, because we are not following
! * immediately after a wildcard character.
! */
! NextByte(t, tlen);
! NextByte(p, plen);
}
I'd suggest adding something like "If we are in the middle of a
multibyte character, we must already have matched at least one byte of
the character from both text and pattern; so we cannot get out-of-sync
on character boundaries. And we know that no backend-legal encoding
allows ASCII characters such as '%' to appear as non-first bytes of
characters, so we won't mistakenly detect a new wildcard."
Done, and committed.
cheers
andrew
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