xref: /illumos-gate/usr/src/cmd/eqn/lex.c (revision 8119dad84d6416f13557b0ba8e2aaf9064cbcfd3)
1 /*
2  * Copyright 2005 Sun Microsystems, Inc.  All rights reserved.
3  * Use is subject to license terms.
4  */
5 
6 /*	Copyright (c) 1984, 1986, 1987, 1988, 1989 AT&T	*/
7 /*	  All Rights Reserved  	*/
8 
9 /*
10  * Copyright (c) 1980 Regents of the University of California.
11  * All rights reserved. The Berkeley software License Agreement
12  * specifies the terms and conditions for redistribution.
13  */
14 
15 #include "e.h"
16 #include "e.def"
17 #include <locale.h>
18 
19 #define	SSIZE	400
20 char	token[SSIZE];
21 int	sp;
22 #define	putbak(c)	*ip++ = c;
23 #define	PUSHBACK	300	/* maximum pushback characters */
24 char	ibuf[PUSHBACK+SSIZE];	/* pushback buffer for definitions, etc. */
25 char	*ip	= ibuf;
26 
27 extern tbl *keytbl[];
28 extern tbl *deftbl[];
29 
30 void define(int);
31 void delim(void);
32 void getstr(char *, int);
33 void include(void);
34 int openinfile(void);
35 void pbstr(char *);
36 void space(void);
37 
38 int
39 gtc(void)
40 {
41 loop:
42 	if (ip > ibuf)
43 		return (*--ip);	/* already present */
44 	lastchar = getc(curfile);
45 	if (lastchar == '\n')
46 		linect++;
47 	if (lastchar != EOF)
48 		return (lastchar);
49 	if (++ifile > svargc) {
50 		return (EOF);
51 	}
52 	(void) fclose(curfile);
53 	linect = 1;
54 	if (openinfile() == 0)
55 		goto loop;
56 	return (EOF);
57 }
58 /*
59  *	open file indexed by ifile in svargv, return non zero if fail
60  */
61 int
62 openinfile(void)
63 {
64 	if (strcmp(svargv[ifile], "-") == 0) {
65 		curfile = stdin;
66 		return (0);
67 	} else if ((curfile = fopen(svargv[ifile], "r")) != NULL) {
68 		return (0);
69 	}
70 	error(FATAL, gettext("can't open file %s"), svargv[ifile]);
71 	return (1);
72 }
73 
74 void
75 pbstr(char *str)
76 {
77 	char *p;
78 
79 	p = str;
80 	while (*p++)
81 		;
82 	--p;
83 	if (ip >= &ibuf[PUSHBACK])
84 		error(FATAL, gettext("pushback overflow"));
85 	while (p > str)
86 		putbak(*--p);
87 }
88 
89 int
90 yylex(void)
91 {
92 	int c;
93 	tbl *tp, *lookup();
94 
95 beg:
96 	while ((c = gtc()) == ' ' || c == '\n')
97 		;
98 	yylval = c;
99 	switch (c) {
100 
101 	case EOF:
102 		return (EOF);
103 	case '~':
104 		return (SPACE);
105 	case '^':
106 		return (THIN);
107 	case '\t':
108 		return (TAB);
109 	case '{':
110 		return ('{');
111 	case '}':
112 		return ('}');
113 	case '"':
114 		for (sp = 0; (c = gtc()) != '"' && c != '\n'; ) {
115 			if (c == '\\')
116 				if ((c = gtc()) != '"')
117 					token[sp++] = '\\';
118 			token[sp++] = c;
119 			if (sp >= SSIZE)
120 				error(FATAL, gettext(
121 				    "quoted string %.20s... too long"), token);
122 		}
123 		token[sp] = '\0';
124 		yylval = (int)&token[0];
125 		if (c == '\n')
126 			error(!FATAL, gettext("missing \" in %.20s"), token);
127 		return (QTEXT);
128 	}
129 	if (c == righteq)
130 		return (EOF);
131 
132 	putbak(c);
133 	getstr(token, SSIZE);
134 	if (dbg) printf(".\tlex token = |%s|\n", token);
135 	if ((tp = lookup(deftbl, token, NULL)) != NULL) {
136 		putbak(' ');
137 		pbstr(tp->defn);
138 		putbak(' ');
139 		if (dbg)
140 			printf(".\tfound %s|=%s|\n", token, tp->defn);
141 	} else if ((tp = lookup(keytbl, token, NULL)) == NULL) {
142 		if (dbg) printf(".\t%s is not a keyword\n", token);
143 		return (CONTIG);
144 	} else if (tp->defn == (char *)DEFINE ||
145 	    tp->defn == (char *)NDEFINE || tp->defn == (char *)TDEFINE)
146 		define((int)tp->defn);
147 	else if (tp->defn == (char *)DELIM)
148 		delim();
149 	else if (tp->defn == (char *)GSIZE)
150 		globsize();
151 	else if (tp->defn == (char *)GFONT)
152 		globfont();
153 	else if (tp->defn == (char *)INCLUDE)
154 		include();
155 	else if (tp->defn == (char *)SPACE)
156 		space();
157 	else {
158 		return ((int)tp->defn);
159 	}
160 	goto beg;
161 }
162 
163 void
164 getstr(char *s, int n)
165 {
166 	int c;
167 	char *p;
168 
169 	p = s;
170 	while ((c = gtc()) == ' ' || c == '\n')
171 		;
172 	if (c == EOF) {
173 		*s = 0;
174 		return;
175 	}
176 	while (c != ' ' && c != '\t' && c != '\n' && c != '{' && c != '}' &&
177 	    c != '"' && c != '~' && c != '^' && c != righteq) {
178 		if (c == '\\')
179 			if ((c = gtc()) != '"')
180 				*p++ = '\\';
181 		*p++ = c;
182 		if (--n <= 0)
183 			error(FATAL, gettext("token %.20s... too long"), s);
184 		c = gtc();
185 	}
186 	if (c == '{' || c == '}' || c == '"' || c == '~' || c == '^' ||
187 	    c == '\t' || c == righteq)
188 		putbak(c);
189 	*p = '\0';
190 	yylval = (int)s;
191 }
192 
193 int
194 cstr(char *s, int quote, int maxs)
195 {
196 	int del, c, i;
197 
198 	s[0] = 0;
199 	while ((del = gtc()) == ' ' || del == '\t')
200 		;
201 	if (quote) {
202 		for (i = 0; (c = gtc()) != del && c != EOF; ) {
203 			s[i++] = c;
204 			if (i >= maxs)
205 				return (1);	/* disaster */
206 		}
207 	} else {
208 		if (del == '\n')
209 			return (1);
210 		s[0] = del;
211 		for (i = 1; (c = gtc()) != ' ' && c != '\t' &&
212 		    c != '\n' && c != EOF; /* empty */) {
213 			s[i++] = c;
214 			if (i >= maxs)
215 				return (1);	/* disaster */
216 		}
217 	}
218 	s[i] = '\0';
219 	if (c == EOF)
220 		error(FATAL, gettext("Unexpected end of input at %.20s"), s);
221 	return (0);
222 }
223 
224 void
225 define(int type)
226 {
227 	char *strsave(), *p1, *p2;
228 	tbl *lookup();
229 
230 	getstr(token, SSIZE);	/* get name */
231 	if (type != DEFINE) {
232 		(void) cstr(token, 1, SSIZE);	/* skip the definition too */
233 		return;
234 	}
235 	p1 = strsave(token);
236 	if (cstr(token, 1, SSIZE))
237 		error(FATAL, gettext(
238 		    "Unterminated definition at %.20s"), token);
239 	p2 = strsave(token);
240 	lookup(deftbl, p1, p2);
241 	if (dbg) printf(".\tname %s defined as %s\n", p1, p2);
242 }
243 
244 char    *spaceval   = NULL;
245 
246 void
247 space(void) /* collect line of form "space amt" to replace \x in output */
248 {
249 	char *strsave();
250 
251 	getstr(token, SSIZE);
252 	spaceval = strsave(token);
253 	if (dbg) printf(".\tsetting space to %s\n", token);
254 }
255 
256 
257 char *
258 strsave(char *s)
259 {
260 	char *malloc();
261 	char *q;
262 
263 	q = malloc(strlen(s)+1);
264 	if (q == NULL)
265 		error(FATAL, gettext("out of space in strsave on %s"), s);
266 	strcpy(q, s);
267 	return (q);
268 }
269 
270 void
271 include(void)
272 {
273 	error(!FATAL, gettext("Include not yet implemented"));
274 }
275 
276 void
277 delim(void)
278 {
279 	yyval = eqnreg = 0;
280 	if (cstr(token, 0, SSIZE))
281 		error(FATAL, gettext("Bizarre delimiters at %.20s"), token);
282 	lefteq = token[0];
283 	righteq = token[1];
284 	if (lefteq == 'o' && righteq == 'f')
285 		lefteq = righteq = '\0';
286 }
287