Fix bugs in sqlchar_to_unicode and unicode_to_sqlchar: both were measuring

the length of a UTF8 character with pg_mblen (wrong if DB encoding isn't
UTF8), and the latter was blithely assuming that a static buffer would somehow
revert to all zeroes for each use.

diff --git a/src/backend/utils/adt/xml.c b/src/backend/utils/adt/xml.c
index 25c320a52d55ad7cbd658d4f124ce4183c54a3fa..adebee6a478f484f358766cc94afa21bdf4b2ac1 100644 (file)
--- a/src/backend/utils/adt/xml.c
+++ b/src/backend/utils/adt/xml.c
@@ -1405,7 +1405,11 @@ sqlchar_to_unicode(char *s)
                                                                                                        GetDatabaseEncoding(),
                                                                                                        PG_UTF8);
 
-       pg_encoding_mb2wchar_with_len(PG_UTF8, utf8string, ret, pg_mblen(s));
+       pg_encoding_mb2wchar_with_len(PG_UTF8, utf8string, ret,
+                                                                 pg_encoding_mblen(PG_UTF8, utf8string));
+
+       if (utf8string != s)
+               pfree(utf8string);
 
        return ret[0];
 }
@@ -1495,14 +1499,21 @@ map_sql_identifier_to_xml_name(char *ident, bool fully_escaped,
 static char *
 unicode_to_sqlchar(pg_wchar c)
 {
-       static unsigned char utf8string[5]; /* need trailing zero */
+       unsigned char utf8string[5]; /* need room for trailing zero */
+       char       *result;
 
+       memset(utf8string, 0, sizeof(utf8string));
        unicode_to_utf8(c, utf8string);
 
-       return (char *) pg_do_encoding_conversion(utf8string,
-                                                                                         pg_mblen((char *) utf8string),
-                                                                                         PG_UTF8,
-                                                                                         GetDatabaseEncoding());
+       result = (char *) pg_do_encoding_conversion(utf8string,
+                                                                                               pg_encoding_mblen(PG_UTF8,
+                                                                                                                (char *) utf8string),
+                                                                                               PG_UTF8,
+                                                                                               GetDatabaseEncoding());
+       /* if pg_do_encoding_conversion didn't strdup, we must */
+       if (result == (char *) utf8string)
+               result = pstrdup(result);
+       return result;
 }