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 6e18a41db1e6c42c5501c8af473d4860eae68e37..f8c18689f8406139c4aab358171b7ff724a0a2aa 100644 (file)
--- a/src/backend/parser/scan.l
+++ b/src/backend/parser/scan.l
@@ -620,28 +620,32 @@ other                     .
                                        return IDENT;
                                }
 <xui>{xuistop1}        {
-                                       char               *ident;
+                                       char       *ident;
+                                       int                     identlen;
 
                                        BEGIN(INITIAL);
                                        if (literallen == 0)
                                                yyerror("zero-length delimited identifier");
                                        ident = litbuf_udeescape('\\');
-                                       if (literallen >= NAMEDATALEN)
-                                               truncate_identifier(ident, 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 (literallen == 0)
                                                yyerror("zero-length delimited identifier");
                                        ident = litbuf_udeescape(yytext[yyleng - 2]);
-                                       if (literallen >= NAMEDATALEN)
-                                               truncate_identifier(ident, literallen, true);
+                                       identlen = strlen(ident);
+                                       if (identlen >= NAMEDATALEN)
+                                               truncate_identifier(ident, identlen, true);
                                        yylval.str = ident;
                                        return IDENT;
                                }