xref: /original-bsd/lib/libterm/termcap.c (revision 860e07fc)
1 /*
2  * Copyright (c) 1980 The Regents of the University of California.
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  * 3. All advertising materials mentioning features or use of this software
14  *    must display the following acknowledgement:
15  *	This product includes software developed by the University of
16  *	California, Berkeley and its contributors.
17  * 4. Neither the name of the University nor the names of its contributors
18  *    may be used to endorse or promote products derived from this software
19  *    without specific prior written permission.
20  *
21  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31  * SUCH DAMAGE.
32  */
33 
34 #ifndef lint
35 static char sccsid[] = "@(#)termcap.c	5.7 (Berkeley) 8/6/92";
36 #endif /* not lint */
37 
38 #define	PBUFSIZ		512	/* max length of filename path */
39 #define	PVECSIZ		32	/* max number of names in path */
40 
41 #include <stdio.h>
42 #include <ctype.h>
43 #include <stdlib.h>
44 #include <string.h>
45 #include "pathnames.h"
46 
47 /*
48  * termcap - routines for dealing with the terminal capability data base
49  *
50  * BUG:		Should use a "last" pointer in tbuf, so that searching
51  *		for capabilities alphabetically would not be a n**2/2
52  *		process when large numbers of capabilities are given.
53  * Note:	If we add a last pointer now we will screw up the
54  *		tc capability. We really should compile termcap.
55  *
56  * Essentially all the work here is scanning and decoding escapes
57  * in string capabilities.  We don't use stdio because the editor
58  * doesn't, and because living w/o it is not hard.
59  */
60 
61 static	char *tbuf;	/* termcap buffer */
62 
63 /*
64  * Get an entry for terminal name in buffer bp from the termcap file.
65  */
66 int
67 tgetent(bp, name)
68 	char *bp, *name;
69 {
70 	register char *p;
71 	register char *cp;
72 	char  *dummy;
73 	char **fname;
74 	char  *home;
75 	int    i;
76 	char   pathbuf[PBUFSIZ];	/* holds raw path of filenames */
77 	char  *pathvec[PVECSIZ];	/* to point to names in pathbuf */
78 	char **pvec;			/* holds usable tail of path vector */
79 	char  *termpath;
80 
81 	fname = pathvec;
82 	pvec = pathvec;
83 	tbuf = bp;
84 	p = pathbuf;
85 	cp = getenv("TERMCAP");
86 	/*
87 	 * TERMCAP can have one of two things in it. It can be the
88 	 * name of a file to use instead of /etc/termcap. In this
89 	 * case it better start with a "/". Or it can be an entry to
90 	 * use so we don't have to read the file. In this case it
91 	 * has to already have the newlines crunched out.  If TERMCAP
92 	 * does not hold a file name then a path of names is searched
93 	 * instead.  The path is found in the TERMPATH variable, or
94 	 * becomes "$HOME/.termcap /etc/termcap" if no TERMPATH exists.
95 	 */
96 	if (!cp || *cp != '/') {	/* no TERMCAP or it holds an entry */
97 		if (termpath = getenv("TERMPATH"))
98 			strncpy(pathbuf, termpath, PBUFSIZ);
99 		else {
100 			if (home = getenv("HOME")) {	/* set up default */
101 				p += strlen(home);	/* path, looking in */
102 				strcpy(pathbuf, home);	/* $HOME first */
103 				*p++ = '/';
104 			}	/* if no $HOME look in current directory */
105 			strncpy(p, _PATH_DEF, PBUFSIZ - (p - pathbuf));
106 		}
107 	}
108 	else				/* user-defined name in TERMCAP */
109 		strncpy(pathbuf, cp, PBUFSIZ);	/* still can be tokenized */
110 
111 	*fname++ = pathbuf;	/* tokenize path into vector of names */
112 	while (*++p)
113 		if (*p == ' ' || *p == ':') {
114 			*p = '\0';
115 			while (*++p)
116 				if (*p != ' ' && *p != ':')
117 					break;
118 			if (*p == '\0')
119 				break;
120 			*fname++ = p;
121 			if (fname >= pathvec + PVECSIZ) {
122 				fname--;
123 				break;
124 			}
125 		}
126 	*fname = (char *) 0;			/* mark end of vector */
127 	if (cp && *cp && *cp != '/')
128 		if (cgetset(cp) < 0)
129 			return(-2);
130 
131 	i = cgetent(&dummy, pathvec, name);
132 
133 	if (i == 0)
134 		strcpy(bp, dummy);
135 
136 	if (dummy)
137 		free(dummy);
138 	/* no tc reference loop return code in libterm XXX */
139 	if (i == -3)
140 		return(-1);
141 	return(i + 1);
142 }
143 
144 /*
145  * Return the (numeric) option id.
146  * Numeric options look like
147  *	li#80
148  * i.e. the option string is separated from the numeric value by
149  * a # character.  If the option is not found we return -1.
150  * Note that we handle octal numbers beginning with 0.
151  */
152 int
153 tgetnum(id)
154 	char *id;
155 {
156 	long num;
157 
158 	if (cgetnum(tbuf, id, &num) == 0)
159 		return(num);
160 	else
161 		return(-1);
162 }
163 
164 /*
165  * Handle a flag option.
166  * Flag options are given "naked", i.e. followed by a : or the end
167  * of the buffer.  Return 1 if we find the option, or 0 if it is
168  * not given.
169  */
170 int
171 tgetflag(id)
172 	char *id;
173 {
174 	return(cgetcap(tbuf, id, ':') != NULL);
175 }
176 
177 /*
178  * Get a string valued option.
179  * These are given as
180  *	cl=^Z
181  * Much decoding is done on the strings, and the strings are
182  * placed in area, which is a ref parameter which is updated.
183  * No checking on area overflow.
184  */
185 char *
186 tgetstr(id, area)
187 	char *id, **area;
188 {
189 	char *s;
190 	int i;
191 
192 	if ((i = cgetstr(tbuf, id, &s)) < 0)
193 		return NULL;
194 
195 	strcpy(*area, s);
196 	*area += i + 1;
197 	return(s);
198 }
199