xref: /freebsd/usr.sbin/config/lang.l (revision 6af83ee0d2941d18880b6aaa2b4facd1d30c6106)
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 <string.h>
37 #include "y.tab.h"
38 #include "config.h"
39 
40 #define YY_NO_UNPUT
41 
42 /*
43  * Data for returning to previous files from include files.
44  */
45 struct incl {
46 	struct	incl *in_prev; 	/* previous includes in effect, if any */
47 	YY_BUFFER_STATE in_buf;	/* previous lex state */
48 	const	char *in_fname;	/* previous file name */
49 	int	in_lineno;	/* previous line number */
50 	int	in_ateof;	/* token to insert at EOF */
51 };
52 static struct	incl *inclp;
53 static const	char *lastfile;
54 
55 /*
56  * Key word table
57  */
58 
59 struct kt {
60 	const char *kt_name;
61 	int kt_val;
62 } key_words[] = {
63 	{ "config",	CONFIG },
64 	{ "cpu",	CPU },
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 	{ "makeoptions", MAKEOPTIONS },
74 	{ "nomakeoption", NOMAKEOPTION },
75 	{ "maxusers",	MAXUSERS },
76 	{ "profile",	PROFILE },
77 	{ "option",	OPTIONS },
78 	{ "options",	OPTIONS },
79 	{ "nooption",	NOOPTION },
80 	{ "nooptions",	NOOPTION },
81 	{ "include",	INCLUDE },
82 	{ "files", 	FILES },
83 	{ 0, 0 },
84 };
85 
86 
87 static int endinclude(void);
88 int include(const char *, int);
89 int kw_lookup(char *);
90 unsigned int octal(const char *);
91 unsigned int hex(const char *);
92 int yyerror(const char *);
93 
94 %}
95 ID	[A-Za-z_][-A-Za-z_0-9]*
96 %START TOEOL
97 %%
98 {ID}		{
99 			int i;
100 
101 			BEGIN 0;
102 			if ((i = kw_lookup(yytext)) == -1)
103 			{
104 				yylval.str = strdup(yytext);
105 				return ID;
106 			}
107 			return i;
108 		}
109 \\\"[^"]+\\\"	{
110 			BEGIN 0;
111 			yytext[yyleng-2] = '"';
112 			yytext[yyleng-1] = '\0';
113 			yylval.str = strdup(yytext + 1);
114 			return ID;
115 		}
116 \"[^"]+\"	{
117 			BEGIN 0;
118 			yytext[yyleng-1] = '\0';
119 			yylval.str = strdup(yytext + 1);
120 			return ID;
121 		}
122 <TOEOL>[^# \t\n]*	{
123 			BEGIN 0;
124 			yylval.str = strdup(yytext);
125 			return ID;
126 		}
127 0[0-7]*		{
128 			yylval.val = octal(yytext);
129 			return NUMBER;
130 		}
131 0x[0-9a-fA-F]+	{
132 			yylval.val = hex(yytext);
133 			return NUMBER;
134 		}
135 -?[1-9][0-9]*	{
136 			yylval.val = atoi(yytext);
137 			return NUMBER;
138 		}
139 "?"		{
140 			yylval.val = -1;
141 			return NUMBER;
142 		}
143 \n/[ \t]	{
144 			yyline++;
145 		}
146 \n		{
147 			yyline++;
148 			return SEMICOLON;
149 		}
150 #.*		{	/* Ignored (comment) */;	}
151 [ \t\f]*	{	/* Ignored (white space) */;	}
152 ";"		{	return SEMICOLON;		}
153 ","		{	return COMMA;			}
154 "="		{	BEGIN TOEOL; return EQUALS;	}
155 <<EOF>>		{
156 			int tok;
157 
158 			if (inclp == NULL)
159 				return YY_NULL;
160 			tok = endinclude();
161 			if (tok != 0)
162 				return tok;
163 			/* otherwise continue scanning */
164 		}
165 .		{	return yytext[0];		}
166 
167 %%
168 /*
169  * kw_lookup
170  *	Look up a string in the keyword table.  Returns a -1 if the
171  *	string is not a keyword otherwise it returns the keyword number
172  */
173 
174 int
175 kw_lookup(char *word)
176 {
177 	struct kt *kp;
178 
179 	for (kp = key_words; kp->kt_name != 0; kp++)
180 		if (eq(word, kp->kt_name))
181 			return kp->kt_val;
182 	return -1;
183 }
184 
185 /*
186  * Number conversion routines
187  */
188 
189 unsigned int
190 octal(const char *str)
191 {
192 	unsigned int num;
193 
194 	(void) sscanf(str, "%o", &num);
195 	return num;
196 }
197 
198 unsigned int
199 hex(const char *str)
200 {
201 	unsigned int num;
202 
203 	(void) sscanf(str+2, "%x", &num);
204 	return num;
205 }
206 
207 
208 /*
209  * Open the named file for inclusion at the current point.  Returns 0 on
210  * success (file opened and previous state pushed), nonzero on failure
211  * (fopen failed, complaint made).  The `ateof' parameter controls the
212  * token to be inserted at the end of the include file. If ateof == 0,
213  * then nothing is inserted.
214  */
215 int
216 include(const char *fname, int ateof)
217 {
218 	FILE *fp;
219 	struct incl *in;
220 	char *fnamebuf;
221 
222 	fp = fopen(fname, "r");
223 	if (fp == NULL && fname[0] != '.' && fname[0] != '/') {
224 		asprintf(&fnamebuf, "../../conf/%s", fname);
225 		if (fnamebuf != NULL) {
226 			fp = fopen(fnamebuf, "r");
227 			free(fnamebuf);
228 		}
229 	}
230 	if (fp == NULL) {
231 		yyerror("cannot open included file");
232 		return (-1);
233 	}
234 	in = malloc(sizeof(*in));
235 	assert(in != NULL);
236 	in->in_prev = inclp;
237 	in->in_buf = YY_CURRENT_BUFFER;
238 	in->in_fname = yyfile;
239 	in->in_lineno = yyline;
240 	in->in_ateof = ateof;
241 	inclp = in;
242 	yy_switch_to_buffer(yy_create_buffer(fp, YY_BUF_SIZE));
243 	yyfile = fname;
244 	yyline = 0;
245 	return (0);
246 }
247 
248 /*
249  * Terminate the most recent inclusion.
250  */
251 static int
252 endinclude()
253 {
254 	struct incl *in;
255 	int ateof;
256 
257 	in = inclp;
258 	assert(in != NULL);
259 	inclp = in->in_prev;
260 	lastfile = yyfile;
261 	yy_delete_buffer(YY_CURRENT_BUFFER);
262 	(void)fclose(yyin);
263 	yy_switch_to_buffer(in->in_buf);
264 	yyfile = in->in_fname;
265 	yyline = in->in_lineno;
266 	ateof  = in->in_ateof;
267 	free(in);
268 
269 	return (ateof);
270 }
271