1/*	$NetBSD: main.c,v 1.48 2003/09/14 12:09:29 jmmv Exp $	*/
2
3/*-
4 * Copyright (c) 1991, 1993
5 *	The Regents of the University of California.  All rights reserved.
6 *
7 * This code is derived from software contributed to Berkeley by
8 * Kenneth Almquist.
9 *
10 * Redistribution and use in source and binary forms, with or without
11 * modification, are permitted provided that the following conditions
12 * are met:
13 * 1. Redistributions of source code must retain the above copyright
14 *    notice, this list of conditions and the following disclaimer.
15 * 2. Redistributions in binary form must reproduce the above copyright
16 *    notice, this list of conditions and the following disclaimer in the
17 *    documentation and/or other materials provided with the distribution.
18 * 3. Neither the name of the University nor the names of its contributors
19 *    may be used to endorse or promote products derived from this software
20 *    without specific prior written permission.
21 *
22 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
23 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
24 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
25 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
26 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
27 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
28 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
29 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
30 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
31 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
32 * SUCH DAMAGE.
33 */
34
35#include <sys/cdefs.h>
36#ifndef lint
37__COPYRIGHT("@(#) Copyright (c) 1991, 1993\n\
38	The Regents of the University of California.  All rights reserved.\n");
39#endif /* not lint */
40
41#ifndef lint
42#if 0
43static char sccsid[] = "@(#)main.c	8.7 (Berkeley) 7/19/95";
44#else
45__RCSID("$NetBSD: main.c,v 1.48 2003/09/14 12:09:29 jmmv Exp $");
46#endif
47#endif /* not lint */
48
49#include <errno.h>
50#include <stdio.h>
51#include <signal.h>
52#include <sys/stat.h>
53#include <unistd.h>
54#include <fcntl.h>
55
56
57#include "shell.h"
58#include "main.h"
59#include "options.h"
60#include "output.h"
61#include "parser.h"
62#include "nodes.h"
63#include "expand.h"
64#include "eval.h"
65#include "jobs.h"
66#include "input.h"
67#include "trap.h"
68#include "var.h"
69#include "show.h"
70#include "memalloc.h"
71#include "error.h"
72#include "init.h"
73#include "mystring.h"
74#include "exec.h"
75#include "cd.h"
76
77#define PROFILE 0
78
79int rootpid;
80int rootshell;
81STATIC union node *curcmd;
82STATIC union node *prevcmd;
83#if PROFILE
84short profile_buf[16384];
85extern int etext();
86#endif
87
88STATIC void read_profile(const char *);
89STATIC char *find_dot_file(char *);
90int main(int, char **);
91
92/*
93 * Main routine.  We initialize things, parse the arguments, execute
94 * profiles if we're a login shell, and then call cmdloop to execute
95 * commands.  The setjmp call sets up the location to jump to when an
96 * exception occurs.  When an exception occurs the variable "state"
97 * is used to figure out how far we had gotten.
98 */
99
100int
101main(int argc, char **argv)
102{
103	struct jmploc jmploc;
104	struct stackmark smark;
105	volatile int state;
106	char *shinit;
107
108#if PROFILE
109	monitor(4, etext, profile_buf, sizeof profile_buf, 50);
110#endif
111	state = 0;
112	if (setjmp(jmploc.loc)) {
113		/*
114		 * When a shell procedure is executed, we raise the
115		 * exception EXSHELLPROC to clean up before executing
116		 * the shell procedure.
117		 */
118		switch (exception) {
119		case EXSHELLPROC:
120			rootpid = getpid();
121			rootshell = 1;
122			minusc = NULL;
123			state = 3;
124			break;
125
126		case EXEXEC:
127			exitstatus = exerrno;
128			break;
129
130		case EXERROR:
131			exitstatus = 2;
132			break;
133
134		default:
135			break;
136		}
137
138		if (exception != EXSHELLPROC) {
139			if (state == 0 || iflag == 0 || ! rootshell)
140				exitshell(exitstatus);
141		}
142		reset();
143		if (exception == EXINT
144#if ATTY
145		 && (! attyset() || equal(termval(), "emacs"))
146#endif
147		 ) {
148			out2c('\n');
149			flushout(&errout);
150		}
151		popstackmark(&smark);
152		FORCEINTON;				/* enable interrupts */
153		if (state == 1)
154			goto state1;
155		else if (state == 2)
156			goto state2;
157		else if (state == 3)
158			goto state3;
159		else
160			goto state4;
161	}
162	handler = &jmploc;
163#ifdef DEBUG
164#if DEBUG == 2
165	debug = 1;
166#endif
167	opentrace();
168	trputs("Shell args:  ");  trargs(argv);
169#endif
170	rootpid = getpid();
171	rootshell = 1;
172	init();
173	setstackmark(&smark);
174	procargs(argc, argv);
175	if (argv[0] && argv[0][0] == '-') {
176		state = 1;
177		read_profile("/etc/profile");
178state1:
179		state = 2;
180		read_profile(".profile");
181	}
182state2:
183	state = 3;
184	if (getuid() == geteuid() && getgid() == getegid()) {
185		if ((shinit = lookupvar("ENV")) != NULL && *shinit != '\0') {
186			state = 3;
187			read_profile(shinit);
188		}
189	}
190state3:
191	state = 4;
192	if (sflag == 0 || minusc) {
193		static int sigs[] =  {
194		    SIGINT, SIGQUIT, SIGHUP,
195#ifdef SIGTSTP
196		    SIGTSTP,
197#endif
198		    SIGPIPE
199		};
200#define SIGSSIZE (sizeof(sigs)/sizeof(sigs[0]))
201		int i;
202
203		for (i = 0; i < SIGSSIZE; i++)
204		    setsignal(sigs[i], 0);
205	}
206
207	if (minusc)
208		evalstring(minusc, 0);
209
210	if (sflag || minusc == NULL) {
211state4:	/* XXX ??? - why isn't this before the "if" statement */
212		cmdloop(1);
213	}
214#if PROFILE
215	monitor(0);
216#endif
217	exitshell(exitstatus);
218	/* NOTREACHED */
219}
220
221
222/*
223 * Read and execute commands.  "Top" is nonzero for the top level command
224 * loop; it turns on prompting if the shell is interactive.
225 */
226
227void
228cmdloop(int top)
229{
230	union node *n;
231	struct stackmark smark;
232	int inter;
233	int numeof = 0;
234
235	TRACE(("cmdloop(%d) called\n", top));
236	setstackmark(&smark);
237	for (;;) {
238		if (pendingsigs)
239			dotrap();
240		inter = 0;
241		if (iflag && top) {
242			inter = 1;
243			showjobs(out2, SHOW_CHANGED);
244			flushout(&errout);
245		}
246		n = parsecmd(inter);
247		/* showtree(n); DEBUG */
248		if (n == NEOF) {
249			if (!top || numeof >= 50)
250				break;
251			if (!stoppedjobs()) {
252				if (!Iflag)
253					break;
254				out2str("\nUse \"exit\" to leave shell.\n");
255			}
256			numeof++;
257		} else if (n != NULL && nflag == 0) {
258			job_warning = (job_warning == 2) ? 1 : 0;
259			numeof = 0;
260			evaltree(n, 0);
261		}
262		popstackmark(&smark);
263		setstackmark(&smark);
264		if (evalskip == SKIPFILE) {
265			evalskip = 0;
266			break;
267		}
268	}
269	popstackmark(&smark);
270}
271
272
273
274/*
275 * Read /etc/profile or .profile.  Return on error.
276 */
277
278STATIC void
279read_profile(const char *name)
280{
281	int fd;
282	int xflag_set = 0;
283	int vflag_set = 0;
284
285	INTOFF;
286	if ((fd = open(name, O_RDONLY)) >= 0)
287		setinputfd(fd, 1);
288	INTON;
289	if (fd < 0)
290		return;
291	/* -q turns off -x and -v just when executing init files */
292	if (qflag)  {
293	    if (xflag)
294		    xflag = 0, xflag_set = 1;
295	    if (vflag)
296		    vflag = 0, vflag_set = 1;
297	}
298	cmdloop(0);
299	if (qflag)  {
300	    if (xflag_set)
301		    xflag = 1;
302	    if (vflag_set)
303		    vflag = 1;
304	}
305	popfile();
306}
307
308
309
310/*
311 * Read a file containing shell functions.
312 */
313
314void
315readcmdfile(char *name)
316{
317	int fd;
318
319	INTOFF;
320	if ((fd = open(name, O_RDONLY)) >= 0)
321		setinputfd(fd, 1);
322	else
323		error("Can't open %s", name);
324	INTON;
325	cmdloop(0);
326	popfile();
327}
328
329
330
331/*
332 * Take commands from a file.  To be compatible we should do a path
333 * search for the file, which is necessary to find sub-commands.
334 */
335
336
337STATIC char *
338find_dot_file(char *basename)
339{
340	char *fullname;
341	const char *path = pathval();
342	struct stat statb;
343
344	/* don't try this for absolute or relative paths */
345	if (strchr(basename, '/'))
346		return basename;
347
348	while ((fullname = padvance(&path, basename)) != NULL) {
349		if ((stat(fullname, &statb) == 0) && S_ISREG(statb.st_mode)) {
350			/*
351			 * Don't bother freeing here, since it will
352			 * be freed by the caller.
353			 */
354			return fullname;
355		}
356		stunalloc(fullname);
357	}
358
359	/* not found in the PATH */
360	error("%s: not found", basename);
361	/* NOTREACHED */
362}
363
364int
365dotcmd(int argc, char **argv)
366{
367	exitstatus = 0;
368
369	if (argc >= 2) {		/* That's what SVR2 does */
370		char *fullname;
371		struct stackmark smark;
372
373		setstackmark(&smark);
374		fullname = find_dot_file(argv[1]);
375		setinputfile(fullname, 1);
376		commandname = fullname;
377		cmdloop(0);
378		popfile();
379		popstackmark(&smark);
380	}
381	return exitstatus;
382}
383
384
385int
386exitcmd(int argc, char **argv)
387{
388	if (stoppedjobs())
389		return 0;
390	if (argc > 1)
391		exitstatus = number(argv[1]);
392	exitshell(exitstatus);
393	/* NOTREACHED */
394}
395