From 9f01c475421ccfcad25607773e2d9b72a002bce3 Mon Sep 17 00:00:00 2001
From: Andrew Johnson <anj@aps.anl.gov>
Date: Thu, 20 Apr 2017 16:23:36 -0500
Subject: [PATCH] Allow whitespace before comments in AS config files

Fixes lp: #1677302
Makes the lexer patterns more like dbStatic.
Handle non-printable invalid characters in input properly.
---
 src/as/asLib_lex.l | 52 ++++++++++++++++++++++++++++------------------
 1 file changed, 32 insertions(+), 20 deletions(-)

diff --git a/src/as/asLib_lex.l b/src/as/asLib_lex.l
index 5e0451925..924105c14 100644
--- a/src/as/asLib_lex.l
+++ b/src/as/asLib_lex.l
@@ -3,18 +3,21 @@
 *     National Laboratory.
 * Copyright (c) 2002 The Regents of the University of California, as
 *     Operator of Los Alamos National Laboratory.
-* EPICS BASE Versions 3.13.7
-* and higher are distributed subject to a Software License Agreement found
-* in file LICENSE that is included with this distribution. 
+* EPICS BASE is distributed subject to a Software License Agreement found
+* in file LICENSE that is included with this distribution.
 \*************************************************************************/
-digit	[0-9]
-name	[a-zA-Z0-9_\-:\.\[\]<>;]
-notquote [^\"]
-escapequote \\\"
-string {notquote}|{escapequote}
+newline     "\n"
+backslash   "\\"
+doublequote "\""
+comment     "#"
 whitespace  [ \t\r]
+escape      {backslash}.
+stringchar  [^"\n\\]
+
+name        [a-zA-Z0-9_\-+:.\[\]<>;]
+digit       [0-9]
 punctuation [(){},]
-link	[A-L]
+link        [A-L]
 
 %{
 static ASINPUTFUNCPTR *my_yyinput;
@@ -37,46 +40,55 @@ HAG	{ return(tokenHAG);	}
 ASG	{ return(tokenASG);	}
 RULE	{ return(tokenRULE);	}
 CALC	{ return(tokenCALC);	}
+
 INP{link} {
 	yylval.Int = (unsigned char)yytext[3];
 	yylval.Int -= 'A';
 	return(tokenINP);
-	}
+}
 
 {digit}+ { /*integer*/
 	yylval.Int = atoi((char *)yytext);
 	return(tokenINTEGER);
-	}
+}
 
 {name}+ { /*unquoted string*/
 	yylval.Str=asStrdup(yytext);
 	return(tokenSTRING);
-	}
+}
 
-\"{string}*\" { /*quoted string*/
-	/* making sure that neither double quote gets passed back */
+{doublequote}({stringchar}|{escape})*{doublequote} { /* quoted string */
 	yylval.Str=asStrdup(yytext+1);
 	yylval.Str[strlen(yylval.Str)-1] = '\0';
 	return(tokenSTRING);
-	}
+}
+
+{doublequote}({stringchar}|{escape})*{newline} { /* bad string */
+	yyerror("Newline in quoted string, closing quote missing");
+}
 
 {punctuation}	{ return(yytext[0]); }
 
-^#.*
-{whitespace}	;
+{newline}	{ line_num++; }
 
-\n      { line_num ++;}
+{comment}.*	;
+{whitespace}	;
 
 .	{
 	char message[40];
 	YY_BUFFER_STATE *dummy=0;
 
-	sprintf(message,"invalid character '%c'",yytext[0]);
+	if (isprint((int) yytext[0])) {
+	    sprintf(message, "Invalid character '%c'", yytext[0]);
+	}
+	else {
+	    sprintf(message, "Invalid character 0x%2.2x", yytext[0]);
+	}
 	yyerror(message);
 
 	/*The following suppress compiler warning messages*/
 	if (0) yyunput('c',(unsigned char *) message);
 	if (0) yy_switch_to_buffer(*dummy);
-	}
+}
 
 %%