xref: /freebsd/usr.sbin/config/lang.l (revision 6dcefcac2b043be030851e03a721607b414b666b)
1 %{
2 /*-
3  * Copyright (c) 1980, 1993
4  *	The Regents of the University of California.  All rights reserved.
5  *
6  * Redistribution and use in source and binary forms, with or without
7  * modification, are permitted provided that the following conditions
8  * are met:
9  * 1. Redistributions of source code must retain the above copyright
10  *    notice, this list of conditions and the following disclaimer.
11  * 2. Redistributions in binary form must reproduce the above copyright
12  *    notice, this list of conditions and the following disclaimer in the
13  *    documentation and/or other materials provided with the distribution.
14  * 4. Neither the name of the University nor the names of its contributors
15  *    may be used to endorse or promote products derived from this software
16  *    without specific prior written permission.
17  *
18  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
19  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
20  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
21  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
22  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
23  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
24  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
25  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
26  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
27  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
28  * SUCH DAMAGE.
29  *
30  *	@(#)lang.l	8.1 (Berkeley) 6/6/93
31  * $FreeBSD$
32  */
33 
34 #include <assert.h>
35 #include <ctype.h>
36 #include <err.h>
37 #include <string.h>
38 #include "y.tab.h"
39 #include "config.h"
40 
41 /*
42  * Data for returning to previous files from include files.
43  */
44 struct incl {
45 	struct	incl *in_prev; 	/* previous includes in effect, if any */
46 	YY_BUFFER_STATE in_buf;	/* previous lex state */
47 	const	char *in_fname;	/* previous file name */
48 	int	in_lineno;	/* previous line number */
49 	int	in_ateof;	/* token to insert at EOF */
50 };
51 static struct	incl *inclp;
52 static const	char *lastfile;
53 
54 /*
55  * Key word table
56  */
57 
58 struct kt {
59 	const char *kt_name;
60 	int kt_val;
61 } key_words[] = {
62 	{ "config",	CONFIG },
63 	{ "cpu",	CPU },
64 	{ "nocpu",	NOCPU },
65 	{ "device",	DEVICE },
66 	{ "devices",	DEVICE },
67 	{ "nodevice",	NODEVICE },
68 	{ "nodevices",	NODEVICE },
69 	{ "env",	ENV },
70 	{ "hints",	HINTS },
71 	{ "ident",	IDENT },
72 	{ "machine",	ARCH }, /* MACHINE is defined in /sys/param.h */
73 	{ "makeoption",	MAKEOPTIONS },
74 	{ "makeoptions", MAKEOPTIONS },
75 	{ "nomakeoption", NOMAKEOPTION },
76 	{ "nomakeoptions", NOMAKEOPTION },
77 	{ "maxusers",	MAXUSERS },
78 	{ "profile",	PROFILE },
79 	{ "option",	OPTIONS },
80 	{ "options",	OPTIONS },
81 	{ "nooption",	NOOPTION },
82 	{ "nooptions",	NOOPTION },
83 	{ "include",	INCLUDE },
84 	{ "files", 	FILES },
85 	{ 0, 0 },
86 };
87 
88 
89 static int endinclude(void);
90 int include(const char *, int);
91 int kw_lookup(char *);
92 unsigned int octal(const char *);
93 unsigned int hex(const char *);
94 int yyerror(const char *);
95 
96 #define YY_DECL int yylex(void)
97 %}
98 
99 %option nounput
100 %option noinput
101 
102 ID	[A-Za-z_][-A-Za-z_0-9]*
103 PATH	[./][-/.%^A-Za-z_0-9]+
104 %START TOEOL
105 %%
106 {ID}		{
107 			int i;
108 
109 			BEGIN 0;
110 			if ((i = kw_lookup(yytext)) == -1)
111 			{
112 				yylval.str = strdup(yytext);
113 				return ID;
114 			}
115 			return i;
116 		}
117 \\\"[^"]+\\\"	{
118 			BEGIN 0;
119 			yytext[yyleng-2] = '"';
120 			yytext[yyleng-1] = '\0';
121 			yylval.str = strdup(yytext + 1);
122 			return ID;
123 		}
124 \"[^"]+\"	{
125 			BEGIN 0;
126 			yytext[yyleng-1] = '\0';
127 			yylval.str = strdup(yytext + 1);
128 			return ID;
129 		}
130 <TOEOL>[^# \t\n]*	{
131 			BEGIN 0;
132 			yylval.str = strdup(yytext);
133 			return ID;
134 		}
135 0[0-7]*		{
136 			yylval.val = octal(yytext);
137 			return NUMBER;
138 		}
139 0x[0-9a-fA-F]+	{
140 			yylval.val = hex(yytext);
141 			return NUMBER;
142 		}
143 -?[1-9][0-9]*	{
144 			yylval.val = atoi(yytext);
145 			return NUMBER;
146 		}
147 "?"		{
148 			yylval.val = -1;
149 			return NUMBER;
150 		}
151 \n/[ \t]	{
152 			yyline++;
153 		}
154 \n		{
155 			yyline++;
156 			return SEMICOLON;
157 		}
158 #.*		{	/* Ignored (comment) */;	}
159 [ \t\f]*	{	/* Ignored (white space) */;	}
160 ";"		{	return SEMICOLON;		}
161 ","		{	return COMMA;			}
162 "="		{	BEGIN TOEOL; return EQUALS;	}
163 "+="		{	BEGIN TOEOL; return PLUSEQUALS;	}
164 <<EOF>>		{
165 			int tok;
166 
167 			if (inclp == NULL)
168 				return YY_NULL;
169 			tok = endinclude();
170 			if (tok != 0)
171 				return tok;
172 			/* otherwise continue scanning */
173 		}
174 {PATH}		{
175 			BEGIN 0;
176 			yylval.str = strdup(yytext);
177 			return PATH;
178 		}
179 .		{	return yytext[0];		}
180 
181 %%
182 /*
183  * kw_lookup
184  *	Look up a string in the keyword table.  Returns a -1 if the
185  *	string is not a keyword otherwise it returns the keyword number
186  */
187 
188 int
189 kw_lookup(char *word)
190 {
191 	struct kt *kp;
192 
193 	for (kp = key_words; kp->kt_name != 0; kp++)
194 		if (eq(word, kp->kt_name))
195 			return kp->kt_val;
196 	return -1;
197 }
198 
199 /*
200  * Number conversion routines
201  */
202 
203 unsigned int
204 octal(const char *str)
205 {
206 	unsigned int num;
207 
208 	(void) sscanf(str, "%o", &num);
209 	return num;
210 }
211 
212 unsigned int
213 hex(const char *str)
214 {
215 	unsigned int num;
216 
217 	(void) sscanf(str+2, "%x", &num);
218 	return num;
219 }
220 
221 void
222 cfgfile_add(const char *fname)
223 {
224 	struct cfgfile *cf;
225 
226 	cf = calloc(1, sizeof(*cf));
227 	if (cf == NULL)
228 		err(EXIT_FAILURE, "calloc");
229 	assert(cf != NULL);
230 	asprintf(&cf->cfg_path, "%s", fname);
231 	STAILQ_INSERT_TAIL(&cfgfiles, cf, cfg_next);
232 }
233 
234 void
235 cfgfile_removeall(void)
236 {
237 	struct cfgfile *cf;
238 
239 	while (!STAILQ_EMPTY(&cfgfiles)) {
240 		cf = STAILQ_FIRST(&cfgfiles);
241 		STAILQ_REMOVE_HEAD(&cfgfiles, cfg_next);
242 		if (cf->cfg_path != NULL)
243 			free(cf->cfg_path);
244 		free(cf);
245 	}
246 }
247 
248 /*
249  * Open the named file for inclusion at the current point.  Returns 0 on
250  * success (file opened and previous state pushed), nonzero on failure
251  * (fopen failed, complaint made).  The `ateof' parameter controls the
252  * token to be inserted at the end of the include file. If ateof == 0,
253  * then nothing is inserted.
254  */
255 int
256 include(const char *fname, int ateof)
257 {
258 	FILE *fp;
259 	struct incl *in;
260 	char *fnamebuf;
261 
262 	fnamebuf = NULL;
263 	fp = fopen(fname, "r");
264 	if (fp == NULL && fname[0] != '.' && fname[0] != '/') {
265 		asprintf(&fnamebuf, "../../conf/%s", fname);
266 		if (fnamebuf != NULL) {
267 			fp = fopen(fnamebuf, "r");
268 			free(fnamebuf);
269 		}
270 	}
271 	if (fp == NULL) {
272 		yyerror("cannot open included file");
273 		return (-1);
274 	}
275 	cfgfile_add(fnamebuf == NULL ? fname : fnamebuf);
276 	in = malloc(sizeof(*in));
277 	assert(in != NULL);
278 	in->in_prev = inclp;
279 	in->in_buf = YY_CURRENT_BUFFER;
280 	in->in_fname = yyfile;
281 	in->in_lineno = yyline;
282 	in->in_ateof = ateof;
283 	inclp = in;
284 	yy_switch_to_buffer(yy_create_buffer(fp, YY_BUF_SIZE));
285 	yyfile = fname;
286 	yyline = 0;
287 	return (0);
288 }
289 
290 /*
291  * Terminate the most recent inclusion.
292  */
293 static int
294 endinclude(void)
295 {
296 	struct incl *in;
297 	int ateof;
298 
299 	in = inclp;
300 	assert(in != NULL);
301 	inclp = in->in_prev;
302 	lastfile = yyfile;
303 	yy_delete_buffer(YY_CURRENT_BUFFER);
304 	(void)fclose(yyin);
305 	yy_switch_to_buffer(in->in_buf);
306 	yyfile = in->in_fname;
307 	yyline = in->in_lineno;
308 	ateof  = in->in_ateof;
309 	free(in);
310 
311 	return (ateof);
312 }
313