1/*-
2 * Copyright (c) 1991, 1993
3 *	The Regents of the University of California.  All rights reserved.
4 *
5 * This code is derived from software contributed to Berkeley by
6 * Kenneth Almquist.
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 * 4. 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#ifndef lint
34static char const copyright[] =
35"@(#) Copyright (c) 1991, 1993\n\
36	The Regents of the University of California.  All rights reserved.\n";
37#endif /* not lint */
38
39#ifndef lint
40#if 0
41static char sccsid[] = "@(#)main.c	8.6 (Berkeley) 5/28/95";
42#endif
43#endif /* not lint */
44#include <sys/cdefs.h>
45__FBSDID("$FreeBSD$");
46
47#include <stdio.h>
48#include <signal.h>
49#include <sys/stat.h>
50#include <unistd.h>
51#include <fcntl.h>
52#include <locale.h>
53#include <errno.h>
54
55#include "shell.h"
56#include "main.h"
57#include "mail.h"
58#include "options.h"
59#include "output.h"
60#include "parser.h"
61#include "nodes.h"
62#include "expand.h"
63#include "eval.h"
64#include "jobs.h"
65#include "input.h"
66#include "trap.h"
67#include "var.h"
68#include "show.h"
69#include "memalloc.h"
70#include "error.h"
71#include "mystring.h"
72#include "exec.h"
73#include "cd.h"
74#include "redir.h"
75#include "builtins.h"
76
77int rootpid;
78int rootshell;
79struct jmploc main_handler;
80int localeisutf8, initial_localeisutf8;
81
82static void reset(void);
83static void cmdloop(int);
84static void read_profile(const char *);
85static char *find_dot_file(char *);
86
87/*
88 * Main routine.  We initialize things, parse the arguments, execute
89 * profiles if we're a login shell, and then call cmdloop to execute
90 * commands.  The setjmp call sets up the location to jump to when an
91 * exception occurs.  When an exception occurs the variable "state"
92 * is used to figure out how far we had gotten.
93 */
94
95int
96main(int argc, char *argv[])
97{
98	struct stackmark smark, smark2;
99	volatile int state;
100	char *shinit;
101
102	(void) setlocale(LC_ALL, "");
103	initcharset();
104	state = 0;
105	if (setjmp(main_handler.loc)) {
106		switch (exception) {
107		case EXEXEC:
108			exitstatus = exerrno;
109			break;
110
111		case EXERROR:
112			exitstatus = 2;
113			break;
114
115		default:
116			break;
117		}
118
119		if (state == 0 || iflag == 0 || ! rootshell ||
120		    exception == EXEXIT)
121			exitshell(exitstatus);
122		reset();
123		if (exception == EXINT)
124			out2fmt_flush("\n");
125		popstackmark(&smark);
126		FORCEINTON;				/* enable interrupts */
127		if (state == 1)
128			goto state1;
129		else if (state == 2)
130			goto state2;
131		else if (state == 3)
132			goto state3;
133		else
134			goto state4;
135	}
136	handler = &main_handler;
137#ifdef DEBUG
138	opentrace();
139	trputs("Shell args:  ");  trargs(argv);
140#endif
141	rootpid = getpid();
142	rootshell = 1;
143	initvar();
144	setstackmark(&smark);
145	setstackmark(&smark2);
146	procargs(argc, argv);
147	pwd_init(iflag);
148	if (iflag)
149		chkmail(1);
150	if (argv[0] && argv[0][0] == '-') {
151		state = 1;
152		read_profile("/etc/profile");
153state1:
154		state = 2;
155		if (privileged == 0)
156			read_profile("${HOME-}/.profile");
157		else
158			read_profile("/etc/suid_profile");
159	}
160state2:
161	state = 3;
162	if (!privileged && iflag) {
163		if ((shinit = lookupvar("ENV")) != NULL && *shinit != '\0') {
164			state = 3;
165			read_profile(shinit);
166		}
167	}
168state3:
169	state = 4;
170	popstackmark(&smark2);
171	if (minusc) {
172		evalstring(minusc, sflag ? 0 : EV_EXIT);
173	}
174state4:
175	if (sflag || minusc == NULL) {
176		cmdloop(1);
177	}
178	exitshell(exitstatus);
179	/*NOTREACHED*/
180	return 0;
181}
182
183static void
184reset(void)
185{
186	reseteval();
187	resetinput();
188}
189
190/*
191 * Read and execute commands.  "Top" is nonzero for the top level command
192 * loop; it turns on prompting if the shell is interactive.
193 */
194
195static void
196cmdloop(int top)
197{
198	union node *n;
199	struct stackmark smark;
200	int inter;
201	int numeof = 0;
202
203	TRACE(("cmdloop(%d) called\n", top));
204	setstackmark(&smark);
205	for (;;) {
206		if (pendingsig)
207			dotrap();
208		inter = 0;
209		if (iflag && top) {
210			inter++;
211			showjobs(1, SHOWJOBS_DEFAULT);
212			chkmail(0);
213			flushout(&output);
214		}
215		n = parsecmd(inter);
216		/* showtree(n); DEBUG */
217		if (n == NEOF) {
218			if (!top || numeof >= 50)
219				break;
220			if (!stoppedjobs()) {
221				if (!Iflag)
222					break;
223				out2fmt_flush("\nUse \"exit\" to leave shell.\n");
224			}
225			numeof++;
226		} else if (n != NULL && nflag == 0) {
227			job_warning = (job_warning == 2) ? 1 : 0;
228			numeof = 0;
229			evaltree(n, 0);
230		}
231		popstackmark(&smark);
232		setstackmark(&smark);
233		if (evalskip != 0) {
234			if (evalskip == SKIPRETURN)
235				evalskip = 0;
236			break;
237		}
238	}
239	popstackmark(&smark);
240}
241
242
243
244/*
245 * Read /etc/profile or .profile.  Return on error.
246 */
247
248static void
249read_profile(const char *name)
250{
251	int fd;
252	const char *expandedname;
253
254	expandedname = expandstr(name);
255	if (expandedname == NULL)
256		return;
257	INTOFF;
258	if ((fd = open(expandedname, O_RDONLY | O_CLOEXEC)) >= 0)
259		setinputfd(fd, 1);
260	INTON;
261	if (fd < 0)
262		return;
263	cmdloop(0);
264	popfile();
265}
266
267
268
269/*
270 * Read a file containing shell functions.
271 */
272
273void
274readcmdfile(const char *name)
275{
276	setinputfile(name, 1);
277	cmdloop(0);
278	popfile();
279}
280
281
282
283/*
284 * Take commands from a file.  To be compatible we should do a path
285 * search for the file, which is necessary to find sub-commands.
286 */
287
288
289static char *
290find_dot_file(char *basename)
291{
292	char *fullname;
293	const char *path = pathval();
294	struct stat statb;
295
296	/* don't try this for absolute or relative paths */
297	if( strchr(basename, '/'))
298		return basename;
299
300	while ((fullname = padvance(&path, basename)) != NULL) {
301		if ((stat(fullname, &statb) == 0) && S_ISREG(statb.st_mode)) {
302			/*
303			 * Don't bother freeing here, since it will
304			 * be freed by the caller.
305			 */
306			return fullname;
307		}
308		stunalloc(fullname);
309	}
310	return basename;
311}
312
313int
314dotcmd(int argc, char **argv)
315{
316	char *filename, *fullname;
317
318	if (argc < 2)
319		error("missing filename");
320
321	exitstatus = 0;
322
323	/*
324	 * Because we have historically not supported any options,
325	 * only treat "--" specially.
326	 */
327	filename = argc > 2 && strcmp(argv[1], "--") == 0 ? argv[2] : argv[1];
328
329	fullname = find_dot_file(filename);
330	setinputfile(fullname, 1);
331	commandname = fullname;
332	cmdloop(0);
333	popfile();
334	return exitstatus;
335}
336
337
338int
339exitcmd(int argc, char **argv)
340{
341	if (stoppedjobs())
342		return 0;
343	if (argc > 1)
344		exitshell(number(argv[1]));
345	else
346		exitshell_savedstatus();
347}
348