Avoid generating invalid character encoding sequences in make_greater_string.

Not sure how this mistake evaded detection for so long.
This commit is contained in:
Tom Lane 2004-02-02 03:07:08 +00:00
parent b8362d465d
commit 9fe097577e
1 changed files with 14 additions and 2 deletions

View File

@ -15,7 +15,7 @@
*
*
* IDENTIFICATION
* $PostgreSQL: pgsql/src/backend/utils/adt/selfuncs.c,v 1.155 2004/01/17 20:09:35 tgl Exp $
* $PostgreSQL: pgsql/src/backend/utils/adt/selfuncs.c,v 1.156 2004/02/02 03:07:08 tgl Exp $
*
*-------------------------------------------------------------------------
*/
@ -3742,6 +3742,11 @@ pattern_selectivity(Const *patt, Pattern_Type ptype)
*
* This could be rather slow in the worst case, but in most cases we
* won't have to try more than one or two strings before succeeding.
*
* NOTE: at present this assumes we are in the C locale, so that simple
* bytewise comparison applies. However, we might be in a multibyte
* encoding such as UTF-8, so we do have to watch out for generating
* invalid encoding sequences.
*/
Const *
make_greater_string(const Const *str_const)
@ -3788,13 +3793,20 @@ make_greater_string(const Const *str_const)
/*
* Try to generate a larger string by incrementing the last byte.
*/
if (*lastchar < (unsigned char) 255)
while (*lastchar < (unsigned char) 255)
{
Const *workstr_const;
(*lastchar)++;
if (datatype != BYTEAOID)
{
/* do not generate invalid encoding sequences */
if (!pg_verifymbstr((const unsigned char *) workstr,
len, true))
continue;
workstr_const = string_to_const(workstr, datatype);
}
else
workstr_const = string_to_bytea_const(workstr, len);