Infrastructure for upgraded error reporting mechanism. elog.c is

rewritten and the protocol is changed, but most elog calls are still
elog calls.  Also, we need to contemplate mechanisms for controlling
all this functionality --- eg, how much stuff should appear in the
postmaster log?  And what API should libpq expose for it?

src/backend/parser/scan.l

@@ -9,7 +9,7 @@
  *
  *
  * IDENTIFICATION
- *	  $Header: /cvsroot/pgsql/src/backend/parser/scan.l,v 1.103 2002/11/11 03:33:38 tgl Exp $
+ *	  $Header: /cvsroot/pgsql/src/backend/parser/scan.l,v 1.104 2003/04/24 21:16:43 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -33,7 +33,7 @@
 #define YY_READ_BUF_SIZE 16777216
 
 /* Avoid exit() on fatal scanner errors (a bit ugly -- see yy_fatal_error) */
-#define fprintf(file, fmt, msg)  elog(FATAL, "%s", (msg))
+#define fprintf(file, fmt, msg)  ereport(FATAL, (errmsg_internal("%s", msg)))
 
 extern YYSTYPE yylval;
 
@@ -575,12 +575,19 @@ void
 yyerror(const char *message)
 {
 	const char *loc = token_start ? token_start : yytext;
+	int			cursorpos;
+
+	/* in multibyte encodings, return index in characters not bytes */
+	cursorpos = pg_mbstrlen_with_len(scanbuf, loc - scanbuf) + 1;
 
 	if (*loc == YY_END_OF_BUFFER_CHAR)
-		elog(ERROR, "parser: %s at end of input", message);
+		ereport(ERROR,
+				(errmsg("parser: %s at end of input", message),
+				 errposition(cursorpos)));
 	else
-		elog(ERROR, "parser: %s at or near \"%s\" at character %d",
-			 message, loc, (int) (loc - scanbuf + 1));
+		ereport(ERROR,
+				(errmsg("parser: %s at or near \"%s\"", message, loc),
+				 errposition(cursorpos)));
 }
 
 
@@ -591,7 +598,7 @@ void
 scanner_init(StringInfo str)
 {
 	/*
-	 * Might be left over after elog()
+	 * Might be left over after ereport()
 	 */
 	if (YY_CURRENT_BUFFER)
 		yy_delete_buffer(YY_CURRENT_BUFFER);