xref: /openbsd/usr.bin/vi/ex/ex_cd.c (revision a6445c1d)
1 /*	$OpenBSD: ex_cd.c,v 1.10 2014/11/12 04:28:41 bentley Exp $	*/
2 
3 /*-
4  * Copyright (c) 1992, 1993, 1994
5  *	The Regents of the University of California.  All rights reserved.
6  * Copyright (c) 1992, 1993, 1994, 1995, 1996
7  *	Keith Bostic.  All rights reserved.
8  *
9  * See the LICENSE file for redistribution information.
10  */
11 
12 #include "config.h"
13 
14 #include <sys/param.h>
15 #include <sys/queue.h>
16 
17 #include <bitstring.h>
18 #include <errno.h>
19 #include <limits.h>
20 #include <pwd.h>
21 #include <stdio.h>
22 #include <stdlib.h>
23 #include <string.h>
24 #include <unistd.h>
25 
26 #include "../common/common.h"
27 
28 /*
29  * ex_cd -- :cd[!] [directory]
30  *	Change directories.
31  *
32  * PUBLIC: int ex_cd(SCR *, EXCMD *);
33  */
34 int
35 ex_cd(SCR *sp, EXCMD *cmdp)
36 {
37 	struct passwd *pw;
38 	ARGS *ap;
39 	CHAR_T savech;
40 	char *dir, *p, *t;	/* XXX: END OF THE STACK, DON'T TRUST GETCWD. */
41 	char buf[MAXPATHLEN * 2];
42 
43 	/*
44 	 * !!!
45 	 * Historic practice is that the cd isn't attempted if the file has
46 	 * been modified, unless its name begins with a leading '/' or the
47 	 * force flag is set.
48 	 */
49 	if (F_ISSET(sp->ep, F_MODIFIED) &&
50 	    !FL_ISSET(cmdp->iflags, E_C_FORCE) && sp->frp->name[0] != '/') {
51 		msgq(sp, M_ERR,
52     "120|File modified since last complete write; write or use ! to override");
53 		return (1);
54 	}
55 
56 	switch (cmdp->argc) {
57 	case 0:
58 		/* If no argument, change to the user's home directory. */
59 		if ((dir = getenv("HOME")) == NULL || *dir == '\0') {
60 			if ((pw = getpwuid(getuid())) == NULL ||
61 			    pw->pw_dir == NULL || pw->pw_dir[0] == '\0') {
62 				msgq(sp, M_ERR,
63 			   "121|Unable to find home directory location");
64 				return (1);
65 			}
66 			dir = pw->pw_dir;
67 		}
68 		break;
69 	case 1:
70 		dir = cmdp->argv[0]->bp;
71 		break;
72 	default:
73 		abort();
74 	}
75 
76 	/*
77 	 * Try the current directory first.  If this succeeds, don't display
78 	 * a message, vi didn't historically, and it should be obvious to the
79 	 * user where they are.
80 	 */
81 	if (!chdir(dir))
82 		return (0);
83 
84 	/*
85 	 * If moving to the user's home directory, or, the path begins with
86 	 * "/", "./" or "../", it's the only place we try.
87 	 */
88 	if (cmdp->argc == 0 ||
89 	    (ap = cmdp->argv[0])->bp[0] == '/' ||
90 	    (ap->len == 1 && ap->bp[0] == '.') ||
91 	    (ap->len >= 2 && ap->bp[0] == '.' && ap->bp[1] == '.' &&
92 	    (ap->bp[2] == '/' || ap->bp[2] == '\0')))
93 		goto err;
94 
95 	/* Try the O_CDPATH option values. */
96 	for (p = t = O_STR(sp, O_CDPATH);; ++p)
97 		if (*p == '\0' || *p == ':') {
98 			/*
99 			 * Empty strings specify ".".  The only way to get an
100 			 * empty string is a leading colon, colons in a row,
101 			 * or a trailing colon.  Or, to put it the other way,
102 			 * if the length is 1 or less, then we're dealing with
103 			 * ":XXX", "XXX::XXXX" , "XXX:", or "".  Since we've
104 			 * already tried dot, we ignore them all.
105 			 */
106 			if (t < p - 1) {
107 				savech = *p;
108 				*p = '\0';
109 				(void)snprintf(buf,
110 				    sizeof(buf), "%s/%s", t, dir);
111 				*p = savech;
112 				if (!chdir(buf)) {
113 					if (getcwd(buf, sizeof(buf)) != NULL)
114 		msgq_str(sp, M_INFO, buf, "122|New current directory: %s");
115 					return (0);
116 				}
117 			}
118 			t = p + 1;
119 			if (*p == '\0')
120 				break;
121 		}
122 
123 err:	msgq_str(sp, M_SYSERR, dir, "%s");
124 	return (1);
125 }
126