1 /* vi: set sw=4 ts=4: */
2 /*
3  * Copyright 1989 - 1991, Julianne Frances Haugh <jockgrrl@austin.rr.com>
4  * All rights reserved.
5  *
6  * Redistribution and use in source and binary forms, with or without
7  * modification, are permitted provided that the following conditions
8  * are met:
9  * 1. Redistributions of source code must retain the above copyright
10  *    notice, this list of conditions and the following disclaimer.
11  * 2. Redistributions in binary form must reproduce the above copyright
12  *    notice, this list of conditions and the following disclaimer in the
13  *    documentation and/or other materials provided with the distribution.
14  * 3. Neither the name of Julianne F. Haugh nor the names of its contributors
15  *    may be used to endorse or promote products derived from this software
16  *    without specific prior written permission.
17  *
18  * THIS SOFTWARE IS PROVIDED BY JULIE HAUGH AND CONTRIBUTORS ''AS IS'' AND
19  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
20  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
21  * ARE DISCLAIMED.  IN NO EVENT SHALL JULIE HAUGH OR CONTRIBUTORS BE LIABLE
22  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
23  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
24  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
25  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
26  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
27  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
28  * SUCH DAMAGE.
29  */
30 #include "libbb.h"
31 
setup_environment(const char * shell,int flags,const struct passwd * pw)32 void FAST_FUNC setup_environment(const char *shell, int flags, const struct passwd *pw)
33 {
34 	if (!shell || !shell[0])
35 		shell = DEFAULT_SHELL;
36 
37 	/* Change the current working directory to be the home directory
38 	 * of the user */
39 	if (!(flags & SETUP_ENV_NO_CHDIR)) {
40 		if (chdir(pw->pw_dir) != 0) {
41 			bb_error_msg("can't change directory to '%s'", pw->pw_dir);
42 			xchdir((flags & SETUP_ENV_TO_TMP) ? "/tmp" : "/");
43 		}
44 	}
45 
46 	if (flags & SETUP_ENV_CLEARENV) {
47 		const char *term;
48 
49 		/* Leave TERM unchanged. Set HOME, SHELL, USER, LOGNAME, PATH.
50 		 * Unset all other environment variables.  */
51 		term = getenv("TERM");
52 		clearenv();
53 		if (term)
54 			xsetenv("TERM", term);
55 		xsetenv("PATH", (pw->pw_uid ? bb_default_path : bb_default_root_path));
56 		goto shortcut;
57 		// No, gcc (4.2.1) is not clever enougn to do it itself.
58 		//xsetenv("USER",    pw->pw_name);
59 		//xsetenv("LOGNAME", pw->pw_name);
60 		//xsetenv("HOME",    pw->pw_dir);
61 		//xsetenv("SHELL",   shell);
62 	} else if (flags & SETUP_ENV_CHANGEENV) {
63 		/* Set HOME, SHELL, and if not becoming a super-user,
64 		 * USER and LOGNAME.  */
65 		if (pw->pw_uid) {
66  shortcut:
67 			xsetenv("USER",    pw->pw_name);
68 			xsetenv("LOGNAME", pw->pw_name);
69 		}
70 		xsetenv("HOME",    pw->pw_dir);
71 		xsetenv("SHELL",   shell);
72 	}
73 }
74