xref: /freebsd/contrib/nvi/ex/ex_cd.c (revision a0409676120c1e558d0ade943019934e0f15118d)
1 /*-
2  * Copyright (c) 1992, 1993, 1994
3  *	The Regents of the University of California.  All rights reserved.
4  * Copyright (c) 1992, 1993, 1994, 1995, 1996
5  *	Keith Bostic.  All rights reserved.
6  *
7  * See the LICENSE file for redistribution information.
8  */
9 
10 #include "config.h"
11 
12 #include <sys/queue.h>
13 #include <sys/time.h>
14 
15 #include <bitstring.h>
16 #include <errno.h>
17 #include <limits.h>
18 #include <pwd.h>
19 #include <stdio.h>
20 #include <stdlib.h>
21 #include <string.h>
22 #include <unistd.h>
23 
24 #include "../common/common.h"
25 
26 /*
27  * ex_cd -- :cd[!] [directory]
28  *	Change directories.
29  *
30  * PUBLIC: int ex_cd(SCR *, EXCMD *);
31  */
32 int
33 ex_cd(SCR *sp, EXCMD *cmdp)
34 {
35 	struct passwd *pw;
36 	ARGS *ap;
37 	int savech;
38 	char *dir, *p, *t;
39 	char *buf;
40 	size_t dlen;
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     "120|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) {
59 			if ((pw = getpwuid(getuid())) == NULL ||
60 			    pw->pw_dir == NULL || pw->pw_dir[0] == '\0') {
61 				msgq(sp, M_ERR,
62 			   "121|Unable to find home directory location");
63 				return (1);
64 			}
65 			dir = pw->pw_dir;
66 		}
67 		break;
68 	case 1:
69 		INT2CHAR(sp, cmdp->argv[0]->bp, cmdp->argv[0]->len + 1,
70 			 dir, dlen);
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 			 * Ignore the empty strings and ".", since we've already
100 			 * tried the current directory.
101 			 */
102 			if (t < p && (p - t != 1 || *t != '.')) {
103 				savech = *p;
104 				*p = '\0';
105 				if ((buf = join(t, dir)) == NULL) {
106 					msgq(sp, M_SYSERR, NULL);
107 					return (1);
108 				}
109 				*p = savech;
110 				if (!chdir(buf)) {
111 					free(buf);
112 					if ((buf = getcwd(NULL, 0)) != NULL) {
113 		msgq_str(sp, M_INFO, buf, "122|New current directory: %s");
114 						free(buf);
115 					}
116 					return (0);
117 				}
118 				free(buf);
119 			}
120 			t = p + 1;
121 			if (*p == '\0')
122 				break;
123 		}
124 
125 err:	msgq_str(sp, M_SYSERR, dir, "%s");
126 	return (1);
127 }
128