xref: /openbsd/usr.bin/vi/ex/ex_cd.c (revision 9b7c3dbb)
1 /*	$OpenBSD: ex_cd.c,v 1.15 2016/05/27 09:18:12 martijn 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/queue.h>
15 
16 #include <bitstring.h>
17 #include <errno.h>
18 #include <limits.h>
19 #include <pwd.h>
20 #include <stdio.h>
21 #include <stdlib.h>
22 #include <string.h>
23 #include <unistd.h>
24 
25 #include "../common/common.h"
26 
27 /*
28  * ex_cd -- :cd[!] [directory]
29  *	Change directories.
30  *
31  * PUBLIC: int ex_cd(SCR *, EXCMD *);
32  */
33 int
34 ex_cd(SCR *sp, EXCMD *cmdp)
35 {
36 	struct passwd *pw;
37 	ARGS *ap;
38 	CHAR_T savech;
39 	char *dir, *p, *t;
40 	char buf[PATH_MAX * 2];
41 
42 	/*
43 	 * !!!
44 	 * Historic practice is that the cd isn't attempted if the file has
45 	 * been modified, unless its name begins with a leading '/' or the
46 	 * force flag is set.
47 	 */
48 	if (F_ISSET(sp->ep, F_MODIFIED) &&
49 	    !FL_ISSET(cmdp->iflags, E_C_FORCE) && sp->frp->name[0] != '/') {
50 		msgq(sp, M_ERR,
51     "File modified since last complete write; write or use ! to override");
52 		return (1);
53 	}
54 
55 	switch (cmdp->argc) {
56 	case 0:
57 		/* If no argument, change to the user's home directory. */
58 		if ((dir = getenv("HOME")) == NULL || *dir == '\0') {
59 			if ((pw = getpwuid(getuid())) == NULL ||
60 			    pw->pw_dir == NULL || pw->pw_dir[0] == '\0') {
61 				msgq(sp, M_ERR,
62 			   "Unable to find home directory location");
63 				return (1);
64 			}
65 			dir = pw->pw_dir;
66 		}
67 		break;
68 	case 1:
69 		dir = cmdp->argv[0]->bp;
70 		break;
71 	default:
72 		abort();
73 	}
74 
75 	/*
76 	 * Try the current directory first.  If this succeeds, don't display
77 	 * a message, vi didn't historically, and it should be obvious to the
78 	 * user where they are.
79 	 */
80 	if (!chdir(dir))
81 		return (0);
82 
83 	/*
84 	 * If moving to the user's home directory, or, the path begins with
85 	 * "/", "./" or "../", it's the only place we try.
86 	 */
87 	if (cmdp->argc == 0 ||
88 	    (ap = cmdp->argv[0])->bp[0] == '/' ||
89 	    (ap->len == 1 && ap->bp[0] == '.') ||
90 	    (ap->len >= 2 && ap->bp[0] == '.' && ap->bp[1] == '.' &&
91 	    (ap->bp[2] == '/' || ap->bp[2] == '\0')))
92 		goto err;
93 
94 	/* Try the O_CDPATH option values. */
95 	for (p = t = O_STR(sp, O_CDPATH);; ++p)
96 		if (*p == '\0' || *p == ':') {
97 			/*
98 			 * Empty strings specify ".".  The only way to get an
99 			 * empty string is a leading colon, colons in a row,
100 			 * or a trailing colon.  Or, to put it the other way,
101 			 * if the length is 1 or less, then we're dealing with
102 			 * ":XXX", "XXX::XXXX" , "XXX:", or "".  Since we've
103 			 * already tried dot, we ignore them all.
104 			 */
105 			if (t < p - 1) {
106 				savech = *p;
107 				*p = '\0';
108 				(void)snprintf(buf,
109 				    sizeof(buf), "%s/%s", t, dir);
110 				*p = savech;
111 				if (!chdir(buf)) {
112 					if (getcwd(buf, sizeof(buf)) != NULL)
113 		msgq_str(sp, M_INFO, buf, "New current directory: %s");
114 					return (0);
115 				}
116 			}
117 			t = p + 1;
118 			if (*p == '\0')
119 				break;
120 		}
121 
122 err:	msgq_str(sp, M_SYSERR, dir, "%s");
123 	return (1);
124 }
125