postgres.git / summary / log / commit / refs

commit    6e6fecf495386e8aebfdc71ad6998eceb9da45e3
Author:   Tom Lane <tgl@sss.pgh.pa.us>
Date:     Fri Feb 19 03:38:55 2021 +0000
First released in: 14.0, 9.6.22, 10.17, 11.12, 12.7, 13.3

    Fix another ancient bug in parsing of BRE-mode regular expressions.
    
    While poking at the regex code, I happened to notice that the bug
    squashed in commit afcc8772e had a sibling: next() failed to return
    a specific value associated with the '}' token for a "\{m,n\}"
    quantifier when parsing in basic RE mode.  Again, this could result
    in treating the quantifier as non-greedy, which it never should be in
    basic mode.  For that to happen, the last character before "\}" that
    sets "nextvalue" would have to set it to zero, or it'd have to have
    accidentally been zero from the start.  The failure can be provoked
    repeatably with, for example, a bound ending in digit "0".
    
    Like the previous patch, back-patch all the way.


 src/backend/regex/regc_lex.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/backend/regex/regc_lex.c b/src/backend/regex/regc_lex.c
index ca2bce48312..16664531641 100644
--- a/src/backend/regex/regc_lex.c
+++ b/src/backend/regex/regc_lex.c
@@ -389,7 +389,7 @@ next(struct vars *v)
 					{
 						v->now++;
 						INTOCON(L_BRE);
-						RET('}');
+						RETV('}', 1);
 					}
 					else
 						FAILW(REG_BADBR);


[parent: 5d319ce86f13]