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 b65ee3e667ab637df3762060b1c5e957712aeee4..772fd4c6a53337f7fe3ddd2d5863f2146f422574 100644 (file)
--- a/src/backend/parser/scan.l
+++ b/src/backend/parser/scan.l
@@ -737,7 +737,8 @@ other           .
 <xuiend>{xustop1} |
 <xuiend><<EOF>>    {
                    /* no UESCAPE after the quote, throw back everything */
-                   char           *ident;
+                   char       *ident;
+                   int         identlen;
 
                    yyless(0);
 
@@ -745,14 +746,16 @@ other         .
                    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;
                    return IDENT;
                }
 <xuiend>{xustop2}  {
                    /* found UESCAPE after the end quote */
-                   char           *ident;
+                   char       *ident;
+                   int         identlen;
 
                    BEGIN(INITIAL);
                    if (yyextra->literallen == 0)
@@ -764,8 +767,9 @@ other           .
                        yyerror("invalid Unicode escape character");
                    }
                    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;
                }