Fix length checking for Unicode identifiers containing escapes (U&"...").

We used the length of the input string, not the de-escaped string, as
the trigger for NAMEDATALEN truncation.  AFAICS this would only result
in sometimes printing a phony truncation warning; but it's just luck
that there was no worse problem, since we were violating the API spec
for truncate_identifier().  Per bug #9204 from Joshua Yanovski.

This has been wrong since the Unicode-identifier support was added,
so back-patch to all supported branches.

diff --git a/src/backend/parser/scan.l b/src/backend/parser/scan.l
index 81502adc95e1ce33580481bbf9fee14c7acf059c..4b5740f2e71cefdcf9980634696e0b5bf8af5e94 100644 (file)
--- a/src/backend/parser/scan.l
+++ b/src/backend/parser/scan.l
@@ -696,28 +696,32 @@ other                     .
                                        return IDENT;
                                }
 <xui>{xuistop1}        {
-                                       char               *ident;
+                                       char       *ident;
+                                       int                     identlen;
 
                                        BEGIN(INITIAL);
                                        if (yyextra->literallen == 0)
                                                yyerror("zero-length delimited identifier");
                                        ident = litbuf_udeescape('\\', yyscanner);
-                                       if (yyextra->literallen >= NAMEDATALEN)
-                                               truncate_identifier(ident, yyextra->literallen, true);
+                                       identlen = strlen(ident);
+                                       if (identlen >= NAMEDATALEN)
+                                               truncate_identifier(ident, identlen, true);
                                        yylval->str = ident;
                                        /* throw back all but the quote */
                                        yyless(1);
                                        return IDENT;
                                }
 <xui>{xuistop2}        {
-                                       char               *ident;
+                                       char       *ident;
+                                       int                     identlen;
 
                                        BEGIN(INITIAL);
                                        if (yyextra->literallen == 0)
                                                yyerror("zero-length delimited identifier");
                                        ident = litbuf_udeescape(yytext[yyleng - 2], yyscanner);
-                                       if (yyextra->literallen >= NAMEDATALEN)
-                                               truncate_identifier(ident, yyextra->literallen, true);
+                                       identlen = strlen(ident);
+                                       if (identlen >= NAMEDATALEN)
+                                               truncate_identifier(ident, identlen, true);
                                        yylval->str = ident;
                                        return IDENT;
                                }