xref: /openbsd/distrib/special/more/termcap.c (revision d415bd75)
1 /*	$OpenBSD: termcap.c,v 1.2 2015/11/15 07:12:50 deraadt Exp $	*/
2 /*	$NetBSD: termcap.c,v 1.7 1995/06/05 19:45:52 pk Exp $	*/
3 
4 /*
5  * Copyright (c) 1980, 1993
6  *	The Regents of the University of California.  All rights reserved.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  * 1. Redistributions of source code must retain the above copyright
12  *    notice, this list of conditions and the following disclaimer.
13  * 2. Redistributions in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in the
15  *    documentation and/or other materials provided with the distribution.
16  * 3. Neither the name of the University nor the names of its contributors
17  *    may be used to endorse or promote products derived from this software
18  *    without specific prior written permission.
19  *
20  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
21  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
24  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
25  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
26  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
27  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
28  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
29  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
30  * SUCH DAMAGE.
31  */
32 
33 #define	PBUFSIZ		512	/* max length of filename path */
34 #define	PVECSIZ		32	/* max number of names in path */
35 
36 #include <stdio.h>
37 #include <ctype.h>
38 #include <stdlib.h>
39 #include <string.h>
40 #include <unistd.h>
41 #include <limits.h>
42 #include <curses.h>
43 #include "pathnames.h"
44 
45 /*
46  * termcap - routines for dealing with the terminal capability data base
47  *
48  * BUG:		Should use a "last" pointer in tbuf, so that searching
49  *		for capabilities alphabetically would not be a n**2/2
50  *		process when large numbers of capabilities are given.
51  * Note:	If we add a last pointer now we will screw up the
52  *		tc capability. We really should compile termcap.
53  *
54  * Essentially all the work here is scanning and decoding escapes
55  * in string capabilities.  We don't use stdio because the editor
56  * doesn't, and because living w/o it is not hard.
57  */
58 
59 static	char *tbuf;	/* termcap buffer */
60 
61 /*
62  * Get an entry for terminal name in buffer bp from the termcap file.
63  */
64 int
65 tgetent(char *bp, char *name)
66 {
67 	char *p, *cp, *dummy, **fname, *home;
68 	int    i;
69 	char   pathbuf[PATH_MAX];	/* holds raw path of filenames */
70 	char  *pathvec[PVECSIZ];	/* to point to names in pathbuf */
71 	char **pvec;			/* holds usable tail of path vector */
72 	char  *termpath;
73 
74 	fname = pathvec;
75 	pvec = pathvec;
76 	tbuf = bp;
77 
78 	cp = issetugid() ? NULL : getenv("TERMCAP");
79 	/*
80 	 * TERMCAP can have one of two things in it. It can be the name
81 	 * of a file to use instead of /usr/share/misc/termcap. In this
82 	 * case it better start with a "/". Or it can be an entry to use
83 	 * so we don't have to read the file. In this case it has to
84 	 * already have the newlines crunched out.  If TERMCAP does not
85 	 * hold a file name then a path of names is searched instead.
86 	 * The path is found in the TERMPATH variable, or becomes
87 	 * "$HOME/.termcap /usr/share/misc/termcap" if no TERMPATH exists.
88 	 */
89 	if (cp == NULL) {
90 		strlcpy(pathbuf, _PATH_TERMCAP, sizeof(pathbuf));
91 	} else if (!cp || *cp != '/') { /* TERMCAP holds an entry */
92 		if ((termpath = getenv("TERMPATH")) != NULL)
93 			strlcpy(pathbuf, termpath, sizeof(pathbuf));
94 		else if ((home = getenv("HOME")) == NULL || *home == '\0' ||
95 		    snprintf(pathbuf, sizeof(pathbuf), "%s/%s", home,
96 		    _PATH_DEF) >= sizeof(pathbuf))
97 			strlcpy(pathbuf, _PATH_DEF, sizeof(pathbuf));
98 	} else {		/* user-defined path in TERMCAP */
99 		/* still can be tokenized */
100 		strlcpy(pathbuf, cp, sizeof(pathbuf));
101 	}
102 	*fname++ = pathbuf;	/* tokenize path into vector of names */
103 
104 	/* split pathbuf into a vector of paths */
105 	p = pathbuf;
106 	while (*++p)
107 		if (*p == ' ' || *p == ':') {
108 			*p = '\0';
109 			while (*++p)
110 				if (*p != ' ' && *p != ':')
111 					break;
112 			if (*p == '\0')
113 				break;
114 			*fname++ = p;
115 			if (fname >= pathvec + PVECSIZ) {
116 				fname--;
117 				break;
118 			}
119 		}
120 	*fname = (char *) 0;			/* mark end of vector */
121 	if (cp && *cp && *cp != '/')
122 		if (cgetset(cp) < 0)
123 			return (-2);
124 
125 	dummy = NULL;
126 	i = cgetent(&dummy, pathvec, name);
127 
128 	if (i == 0 && bp != NULL) {
129 		strlcpy(bp, dummy, 1024);
130 		if ((cp = strrchr(bp, ':')) != NULL)
131 			if (cp[1] != '\0')
132 				cp[1] = '\0';
133 	}
134 	else if (i == 0 && bp == NULL)
135 		tbuf = dummy;
136 	else if (dummy != NULL)
137 		free(dummy);
138 
139 	/* no tc reference loop return code in libterm XXX */
140 	if (i == -3)
141 		return (-1);
142 	return (i + 1);
143 }
144 
145 /*
146  * Return the (numeric) option id.
147  * Numeric options look like
148  *	li#80
149  * i.e. the option string is separated from the numeric value by
150  * a # character.  If the option is not found we return -1.
151  * Note that we handle octal numbers beginning with 0.
152  */
153 int
154 tgetnum(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(char *id)
172 {
173 	return (cgetcap(tbuf, id, ':') != NULL);
174 }
175 
176 /*
177  * Get a string valued option.
178  * These are given as
179  *	cl=^Z
180  * Much decoding is done on the strings, and the strings are
181  * placed in area, which is a ref parameter which is updated.
182  * No checking on area overflow.
183  */
184 char *
185 tgetstr(char *id, char **area)
186 {
187 	char ids[3];
188 	char *s;
189 	int i;
190 
191 	/*
192 	 * XXX
193 	 * This is for all the boneheaded programs that relied on tgetstr
194 	 * to look only at the first 2 characters of the string passed...
195 	 */
196 	*ids = *id;
197 	ids[1] = id[1];
198 	ids[2] = '\0';
199 
200 	if ((i = cgetstr(tbuf, ids, &s)) < 0)
201 		return NULL;
202 
203 	strlcpy(*area, s, 1024);
204 	*area += i + 1;
205 	return (s);
206 }
207