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.

diff --git a/src/backend/regex/regc_lex.c b/src/backend/regex/regc_lex.c
index f9118e8e42a2af9bd67d5c5fcd6f079156c4b889..e44e2be3f3d32aabd3c747cf8d7ebf5bb0a2da51 100644 (file)
--- 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);