in all these programs using the same pfctl-derived parse.y, re-unify the

yylex implementation and the code which interacts with yylex.  this also
brings the future potential for include support to all of the parsers.
in the future please do not silly modifications to one of these files
without checking if you are de-unifying the code.
checked by developers in all these areas.

src/usr.sbin/ntpd/parse.y

@@ -1,4 +1,4 @@
-/*	$OpenBSD: parse.y,v 1.36 2007/10/11 14:39:17 deraadt Exp $ */
+/*	$OpenBSD: parse.y,v 1.37 2007/10/13 16:35:21 deraadt Exp $ */
 
 /*
  * Copyright (c) 2002, 2003, 2004 Henning Brauer <henning@openbsd.org>
@@ -36,20 +36,26 @@
 
 #include "ntpd.h"
 
-static struct ntpd_conf		*conf;
-static FILE			*fin = NULL;
-static int			 lineno = 1;
-static int			 errors = 0;
-const char			*infile;
-
-int	 yyerror(const char *, ...);
-int	 yyparse(void);
-int	 kw_cmp(const void *, const void *);
-int	 lookup(char *);
-int	 lgetc(int);
-int	 lungetc(int);
-int	 findeol(void);
-int	 yylex(void);
+TAILQ_HEAD(files, file)		 files = TAILQ_HEAD_INITIALIZER(files);
+static struct file {
+	TAILQ_ENTRY(file)	 entry;
+	FILE			*stream;
+	char			*name;
+	int			 lineno;
+	int			 errors;
+} *file;
+struct file	*pushfile(const char *);
+int		 popfile(void);
+int		 yyparse(void);
+int		 yylex(void);
+int		 yyerror(const char *, ...);
+int		 kw_cmp(const void *, const void *);
+int		 lookup(char *);
+int		 lgetc(int);
+int		 lungetc(int);
+int		 findeol(void);
+
+struct ntpd_conf		*conf;
 
 struct opts {
 	int		weight;
@@ -59,10 +65,10 @@ void		opts_default(void);
 
 typedef struct {
 	union {
-		int64_t		 	number;
+		int64_t			 number;
 		char			*string;
 		struct ntp_addr_wrap	*addr;
-		struct opts		opts;
+		struct opts		 opts;
 	} v;
 	int lineno;
 } YYSTYPE;
@@ -83,11 +89,11 @@ typedef struct {
 
 grammar		: /* empty */
 		| grammar '\n'
-		| grammar conf_main '\n'
-		| grammar error '\n'		{ errors++; }
+		| grammar main '\n'
+		| grammar error '\n'		{ file->errors++; }
 		;
 
-conf_main	: LISTEN ON address	{
+main		: LISTEN ON address	{
 			struct listen_addr	*la;
 			struct ntp_addr		*h, *next;
 
@@ -279,9 +285,9 @@ yyerror(const char *fmt, ...)
 	va_list		 ap;
 	char		*nfmt;
 
-	errors = 1;
+	file->errors++;
 	va_start(ap, fmt);
-	if (asprintf(&nfmt, "%s:%d: %s", infile, yylval.lineno, fmt) == -1)
+	if (asprintf(&nfmt, "%s:%d: %s", file->name, yylval.lineno, fmt) == -1)
 		fatalx("yyerror asprintf");
 	vlog(LOG_CRIT, nfmt, ap);
 	va_end(ap);
@@ -327,10 +333,9 @@ char	 pushback_buffer[MAXPUSHBACK];
 int	 pushback_index = 0;
 
 int
-lgetc(int inquot)
+lgetc(int quotec)
 {
-	int	c, next;
-	FILE *f = fin;
+	int		c, next;
 
 	if (parsebuf) {
 		/* Read character from the parsebuffer instead of input. */
@@ -346,29 +351,39 @@ lgetc(int inquot)
 	if (pushback_index)
 		return (pushback_buffer[--pushback_index]);
 
-	if (inquot) {
-		c = getc(f);
+	if (quotec) {
+		if ((c = getc(file->stream)) == EOF) {
+			yyerror("reached end of file while parsing quoted string");
+			if (popfile() == EOF)
+				return (EOF);
+			return (quotec);
+		}
 		return (c);
 	}
 
-	while ((c = getc(f)) == '\\') {
-		next = getc(f);
+	while ((c = getc(file->stream)) == '\\') {
+		next = getc(file->stream);
 		if (next != '\n') {
 			c = next;
 			break;
 		}
-		yylval.lineno = lineno;
-		lineno++;
+		yylval.lineno = file->lineno;
+		file->lineno++;
 	}
 	if (c == '\t' || c == ' ') {
 		/* Compress blanks to a single space. */
 		do {
-			c = getc(f);
+			c = getc(file->stream);
 		} while (c == '\t' || c == ' ');
-		ungetc(c, f);
+		ungetc(c, file->stream);
 		c = ' ';
 	}
 
+	while (c == EOF) {
+		if (popfile() == EOF)
+			return (EOF);
+		c = getc(file->stream);
+	}
 	return (c);
 }
 
@@ -400,7 +415,7 @@ findeol(void)
 	while (1) {
 		c = lgetc(0);
 		if (c == '\n') {
-			lineno++;
+			file->lineno++;
 			break;
 		}
 		if (c == EOF)
@@ -414,14 +429,14 @@ yylex(void)
 {
 	char	 buf[8096];
 	char	*p;
-	int	 endc, next, c;
+	int	 quotec, next, c;
 	int	 token;
 
 	p = buf;
 	while ((c = lgetc(0)) == ' ')
 		; /* nothing */
 
-	yylval.lineno = lineno;
+	yylval.lineno = file->lineno;
 	if (c == '#')
 		while ((c = lgetc(0)) != '\n' && c != EOF)
 			; /* nothing */
@@ -429,21 +444,21 @@ yylex(void)
 	switch (c) {
 	case '\'':
 	case '"':
-		endc = c;
+		quotec = c;
 		while (1) {
-			if ((c = lgetc(1)) == EOF)
+			if ((c = lgetc(quotec)) == EOF)
 				return (0);
 			if (c == '\n') {
-				lineno++;
+				file->lineno++;
 				continue;
 			} else if (c == '\\') {
-				if ((next = lgetc(1)) == EOF)
+				if ((next = lgetc(quotec)) == EOF)
 					return (0);
-				if (next == endc)
+				if (next == quotec)
 					c = next;
 				else
 					lungetc(next);
-			} else if (c == endc) {
+			} else if (c == quotec) {
 				*p = '\0';
 				break;
 			}
@@ -517,33 +532,67 @@ nodigits:
 		return (token);
 	}
 	if (c == '\n') {
-		yylval.lineno = lineno;
-		lineno++;
+		yylval.lineno = file->lineno;
+		file->lineno++;
 	}
 	if (c == EOF)
 		return (0);
 	return (c);
 }
 
+struct file *
+pushfile(const char *name)
+{
+	struct file	*nfile;
+
+	if ((nfile = calloc(1, sizeof(struct file))) == NULL ||
+	    (nfile->name = strdup(name)) == NULL)
+		return (NULL);
+	if ((nfile->stream = fopen(nfile->name, "r")) == NULL) {
+		free(nfile->name);
+		free(nfile);
+		return (NULL);
+	}
+	nfile->lineno = 1;
+	TAILQ_INSERT_TAIL(&files, nfile, entry);
+	return (nfile);
+}
+
+int
+popfile(void)
+{
+	struct file	*prev;
+
+	if ((prev = TAILQ_PREV(file, files, entry)) != NULL) {
+		prev->errors += file->errors;
+		TAILQ_REMOVE(&files, file, entry);
+		fclose(file->stream);
+		free(file->name);
+		free(file);
+		file = prev;
+		return (0);
+	}
+	return (EOF);
+}
+
 int
 parse_config(const char *filename, struct ntpd_conf *xconf)
 {
+	int		 errors = 0;
+
 	conf = xconf;
-	lineno = 1;
-	errors = 0;
 	TAILQ_INIT(&conf->listen_addrs);
 	TAILQ_INIT(&conf->ntp_peers);
 	TAILQ_INIT(&conf->ntp_conf_sensors);
 
-	if ((fin = fopen(filename, "r")) == NULL) {
+	if ((file = pushfile(filename)) == NULL) {
 		log_warn("%s", filename);
 		return (-1);
 	}
-	infile = filename;
 
 	yyparse();
-
-	fclose(fin);
+	errors = file->errors;
+	popfile();
 
 	return (errors ? -1 : 0);
 }