From: Tom Lane <tgl@sss.pgh.pa.us>
Date: Thu, 13 Feb 2014 19:24:58 +0000 (-0500)
Subject: Fix length checking for Unicode identifiers containing escapes (U&"...").
X-Git-Tag: REL8_4_20~15
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=a8a46d846c13d1ed07ad0a900e37dd318c8096e2;p=postgresql

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 6e18a41db1..f8c18689f8 100644
--- 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;
 				}