streamline parse buffer handling (no need to copy value that is not

going to go away).

add explicit pushback buffer, to be able to push IPv6 failed parses back.

handle pushback + parse buffer interactions by using negative indices.

okay dhartmei@, deraadt@

1 files changed, 33 insertions, 29 deletions

diff --git a/sbin/pfctl/parse.y b/sbin/pfctl/parse.y
index 51dbf4627cf..26c114be836 100644
--- a/sbin/pfctl/parse.y
+++ b/sbin/pfctl/parse.y
@@ -1,4 +1,4 @@
-/*	$OpenBSD: parse.y,v 1.109 2002/07/01 05:28:22 deraadt Exp $	*/
+/*	$OpenBSD: parse.y,v 1.110 2002/07/01 10:07:40 espie Exp $	*/
 
 /*
  * Copyright (c) 2001 Markus Friedl.  All rights reserved.
@@ -151,8 +151,8 @@ struct sym {
 };
 struct sym *symhead = NULL;
 
-int	symset(char *name, char *val);
-char *	symget(char *name);
+int	symset(const char *name, const char *val);
+char *	symget(const char *name);
 
 struct ifaddrs    *ifa0_lookup(char *ifa_name);
 struct ifaddrs    *ifa4_lookup(char *ifa_name);
@@ -2149,36 +2149,40 @@ lookup(char *s)
 	}
 }
 
+#define MAXPUSHBACK	128
+
 char	*parsebuf;
 int	parseindex;
+char	pushback_buffer[MAXPUSHBACK];
+int	pushback_index = 0;
 
 int
 lgetc(FILE *fin)
 {
 	int c, next;
 
-restart:
 	if (parsebuf) {
 		/* Reading characters from the parse buffer, instead of input */
-		c = parsebuf[parseindex++];
-		if (c != '\0')
-			return (c);
-		free(parsebuf);
-		parsebuf = NULL;
-		parseindex = 0;
-		goto restart;
+		if (parseindex >= 0) {
+			c = parsebuf[parseindex++];
+			if (c != '\0')
+				return (c);
+			parsebuf = NULL;
+		} else
+			parseindex++;
 	}
 
-	c = getc(fin);
-	if (c == '\\') {
+	if (pushback_index)
+		return (pushback_buffer[--pushback_index]);
+
+	while ((c = getc(fin)) == '\\') {
 		next = getc(fin);
 		if (next != '\n') {
 			ungetc(next, fin);
-			return (c);
+			break;
 		}
 		yylval.lineno = lineno;
 		lineno++;
-		goto restart;
 	}
 	return (c);
 }
@@ -2186,12 +2190,17 @@ restart:
 int
 lungetc(int c, FILE *fin)
 {
-	if (parsebuf && parseindex) {
-		/* XXX breaks on index 0 */
+	if (c == EOF)
+		return (EOF);
+	if (parsebuf) {
 		parseindex--;
-		return (c);
+		if (parseindex >= 0)
+			return (c);
 	}
-	return ungetc(c, fin);
+	if (pushback_index < MAXPUSHBACK-1)
+		return (pushback_buffer[pushback_index++] = c);
+	else
+		return (EOF);
 }
 
 int
@@ -2199,11 +2208,8 @@ findeol()
 {
 	int c;
 
-	if (parsebuf) {
-		free(parsebuf);
-		parsebuf = NULL;
-		parseindex = 0;
-	}
+	parsebuf = NULL;
+	pushback_index = 0;
 
 	/* skip to either EOF or the first real EOL */
 	while (1) {
@@ -2254,9 +2260,7 @@ top:
 		val = symget(buf);
 		if (val == NULL)
 			return (ERROR);
-		parsebuf = strdup(val);
-		if (parsebuf == NULL)
-			err(1, "parsebuf: strdup");
+		parsebuf = val;
 		parseindex = 0;
 		goto top;
 	}
@@ -2482,7 +2486,7 @@ ipmask(struct pf_addr *m, u_int8_t b)
  * we wait until they discover this ugliness and make it all fancy.
  */
 int
-symset(char *nam, char *val)
+symset(const char *nam, const char *val)
 {
 	struct sym *sym;
 
@@ -2506,7 +2510,7 @@ symset(char *nam, char *val)
 }
 
 char *
-symget(char *nam)
+symget(const char *nam)
 {
 	struct sym *sym;