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main.c revision 1.26 
      1 /*	$NetBSD: main.c,v 1.26 1997/07/04 21:02:07 christos 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. All advertising materials mentioning features or use of this software
     19  *    must display the following acknowledgement:
     20  *	This product includes software developed by the University of
     21  *	California, Berkeley and its contributors.
     22  * 4. Neither the name of the University nor the names of its contributors
     23  *    may be used to endorse or promote products derived from this software
     24  *    without specific prior written permission.
     25  *
     26  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
     27  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
     28  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
     29  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
     30  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
     31  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
     32  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
     33  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
     34  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
     35  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
     36  * SUCH DAMAGE.
     37  */
     38 
     39 #include <sys/cdefs.h>
     40 #ifndef lint
     41 __COPYRIGHT("@(#) Copyright (c) 1991, 1993\n\
     42 	The Regents of the University of California.  All rights reserved.\n");
     43 #endif /* not lint */
     44 
     45 #ifndef lint
     46 #if 0
     47 static char sccsid[] = "@(#)main.c	8.7 (Berkeley) 7/19/95";
     48 #else
     49 __RCSID("$NetBSD: main.c,v 1.26 1997/07/04 21:02:07 christos Exp $");
     50 #endif
     51 #endif /* not lint */
     52 
     53 #include <stdio.h>
     54 #include <signal.h>
     55 #include <sys/stat.h>
     56 #include <unistd.h>
     57 #include <fcntl.h>
     58 
     59 
     60 #include "shell.h"
     61 #include "main.h"
     62 #include "mail.h"
     63 #include "options.h"
     64 #include "output.h"
     65 #include "parser.h"
     66 #include "nodes.h"
     67 #include "expand.h"
     68 #include "eval.h"
     69 #include "jobs.h"
     70 #include "input.h"
     71 #include "trap.h"
     72 #include "var.h"
     73 #include "show.h"
     74 #include "memalloc.h"
     75 #include "error.h"
     76 #include "init.h"
     77 #include "mystring.h"
     78 #include "exec.h"
     79 #include "cd.h"
     80 
     81 #define PROFILE 0
     82 
     83 int rootpid;
     84 int rootshell;
     85 STATIC union node *curcmd;
     86 STATIC union node *prevcmd;
     87 extern int errno;
     88 #if PROFILE
     89 short profile_buf[16384];
     90 extern int etext();
     91 #endif
     92 
     93 STATIC void read_profile __P((char *));
     94 STATIC char *find_dot_file __P((char *));
     95 int main __P((int, char **));
     96 
     97 /*
     98  * Main routine.  We initialize things, parse the arguments, execute
     99  * profiles if we're a login shell, and then call cmdloop to execute
    100  * commands.  The setjmp call sets up the location to jump to when an
    101  * exception occurs.  When an exception occurs the variable "state"
    102  * is used to figure out how far we had gotten.
    103  */
    104 
    105 int
    106 main(argc, argv)
    107 	int argc;
    108 	char **argv;
    109 {
    110 	struct jmploc jmploc;
    111 	struct stackmark smark;
    112 	volatile int state;
    113 	char *shinit;
    114 
    115 #if PROFILE
    116 	monitor(4, etext, profile_buf, sizeof profile_buf, 50);
    117 #endif
    118 	state = 0;
    119 	if (setjmp(jmploc.loc)) {
    120 		/*
    121 		 * When a shell procedure is executed, we raise the
    122 		 * exception EXSHELLPROC to clean up before executing
    123 		 * the shell procedure.
    124 		 */
    125 		switch (exception) {
    126 		case EXSHELLPROC:
    127 			rootpid = getpid();
    128 			rootshell = 1;
    129 			minusc = NULL;
    130 			state = 3;
    131 			break;
    132 
    133 		case EXEXEC:
    134 			exitstatus = exerrno;
    135 			break;
    136 
    137 		case EXERROR:
    138 			exitstatus = 2;
    139 			break;
    140 
    141 		default:
    142 			break;
    143 		}
    144 
    145 		if (exception != EXSHELLPROC) {
    146 		    if (state == 0 || iflag == 0 || ! rootshell)
    147 			    exitshell(exitstatus);
    148 		}
    149 		reset();
    150 		if (exception == EXINT
    151 #if ATTY
    152 		 && (! attyset() || equal(termval(), "emacs"))
    153 #endif
    154 		 ) {
    155 			out2c('\n');
    156 			flushout(&errout);
    157 		}
    158 		popstackmark(&smark);
    159 		FORCEINTON;				/* enable interrupts */
    160 		if (state == 1)
    161 			goto state1;
    162 		else if (state == 2)
    163 			goto state2;
    164 		else if (state == 3)
    165 			goto state3;
    166 		else
    167 			goto state4;
    168 	}
    169 	handler = &jmploc;
    170 #ifdef DEBUG
    171 	opentrace();
    172 	trputs("Shell args:  ");  trargs(argv);
    173 #endif
    174 	rootpid = getpid();
    175 	rootshell = 1;
    176 	init();
    177 	setstackmark(&smark);
    178 	procargs(argc, argv);
    179 	if (argv[0] && argv[0][0] == '-') {
    180 		state = 1;
    181 		read_profile("/etc/profile");
    182 state1:
    183 		state = 2;
    184 		read_profile(".profile");
    185 	}
    186 state2:
    187 	state = 3;
    188 	if (getuid() == geteuid() && getgid() == getegid()) {
    189 		if ((shinit = lookupvar("ENV")) != NULL && *shinit != '\0') {
    190 			state = 3;
    191 			read_profile(shinit);
    192 		}
    193 	}
    194 state3:
    195 	state = 4;
    196 	if (minusc) {
    197 		evalstring(minusc);
    198 	}
    199 	if (sflag || minusc == NULL) {
    200 state4:	/* XXX ??? - why isn't this before the "if" statement */
    201 		cmdloop(1);
    202 	}
    203 #if PROFILE
    204 	monitor(0);
    205 #endif
    206 	exitshell(exitstatus);
    207 	/*NOTREACHED*/
    208 	return 0;
    209 }
    210 
    211 
    212 /*
    213  * Read and execute commands.  "Top" is nonzero for the top level command
    214  * loop; it turns on prompting if the shell is interactive.
    215  */
    216 
    217 void
    218 cmdloop(top)
    219 	int top;
    220 {
    221 	union node *n;
    222 	struct stackmark smark;
    223 	int inter;
    224 	int numeof = 0;
    225 
    226 	TRACE(("cmdloop(%d) called\n", top));
    227 	setstackmark(&smark);
    228 	for (;;) {
    229 		if (pendingsigs)
    230 			dotrap();
    231 		inter = 0;
    232 		if (iflag && top) {
    233 			inter++;
    234 			showjobs(1);
    235 			chkmail(0);
    236 			flushout(&output);
    237 		}
    238 		n = parsecmd(inter);
    239 		/* showtree(n); DEBUG */
    240 		if (n == NEOF) {
    241 			if (!top || numeof >= 50)
    242 				break;
    243 			if (!stoppedjobs()) {
    244 				if (!Iflag)
    245 					break;
    246 				out2str("\nUse \"exit\" to leave shell.\n");
    247 			}
    248 			numeof++;
    249 		} else if (n != NULL && nflag == 0) {
    250 			job_warning = (job_warning == 2) ? 1 : 0;
    251 			numeof = 0;
    252 			evaltree(n, 0);
    253 		}
    254 		popstackmark(&smark);
    255 		if (evalskip == SKIPFILE) {
    256 			evalskip = 0;
    257 			break;
    258 		}
    259 	}
    260 	popstackmark(&smark);		/* unnecessary */
    261 }
    262 
    263 
    264 
    265 /*
    266  * Read /etc/profile or .profile.  Return on error.
    267  */
    268 
    269 STATIC void
    270 read_profile(name)
    271 	char *name;
    272 	{
    273 	int fd;
    274 
    275 	INTOFF;
    276 	if ((fd = open(name, O_RDONLY)) >= 0)
    277 		setinputfd(fd, 1);
    278 	INTON;
    279 	if (fd < 0)
    280 		return;
    281 	cmdloop(0);
    282 	popfile();
    283 }
    284 
    285 
    286 
    287 /*
    288  * Read a file containing shell functions.
    289  */
    290 
    291 void
    292 readcmdfile(name)
    293 	char *name;
    294 {
    295 	int fd;
    296 
    297 	INTOFF;
    298 	if ((fd = open(name, O_RDONLY)) >= 0)
    299 		setinputfd(fd, 1);
    300 	else
    301 		error("Can't open %s", name);
    302 	INTON;
    303 	cmdloop(0);
    304 	popfile();
    305 }
    306 
    307 
    308 
    309 /*
    310  * Take commands from a file.  To be compatable we should do a path
    311  * search for the file, which is necessary to find sub-commands.
    312  */
    313 
    314 
    315 STATIC char *
    316 find_dot_file(basename)
    317 	char *basename;
    318 {
    319 	static char localname[FILENAME_MAX+1];
    320 	char *fullname;
    321 	char *path = pathval();
    322 	struct stat statb;
    323 
    324 	/* don't try this for absolute or relative paths */
    325 	if( strchr(basename, '/'))
    326 		return basename;
    327 
    328 	while ((fullname = padvance(&path, basename)) != NULL) {
    329 		strcpy(localname, fullname);
    330 		stunalloc(fullname);
    331 		if ((stat(fullname, &statb) == 0) && S_ISREG(statb.st_mode))
    332 			return localname;
    333 	}
    334 	return basename;
    335 }
    336 
    337 int
    338 dotcmd(argc, argv)
    339 	int argc;
    340 	char **argv;
    341 {
    342 	struct strlist *sp;
    343 	exitstatus = 0;
    344 
    345 	for (sp = cmdenviron; sp ; sp = sp->next)
    346 		setvareq(savestr(sp->text), VSTRFIXED|VTEXTFIXED);
    347 
    348 	if (argc >= 2) {		/* That's what SVR2 does */
    349 		char *fullname = find_dot_file(argv[1]);
    350 
    351 		setinputfile(fullname, 1);
    352 		commandname = fullname;
    353 		cmdloop(0);
    354 		popfile();
    355 	}
    356 	return exitstatus;
    357 }
    358 
    359 
    360 int
    361 exitcmd(argc, argv)
    362 	int argc;
    363 	char **argv;
    364 {
    365 	extern int oexitstatus;
    366 
    367 	if (stoppedjobs())
    368 		return 0;
    369 	if (argc > 1)
    370 		exitstatus = number(argv[1]);
    371 	else
    372 		exitstatus = oexitstatus;
    373 	exitshell(exitstatus);
    374 	/*NOTREACHED*/
    375 	return 0;
    376 }
    377 
    378 
    379 #ifdef notdef
    380 /*
    381  * Should never be called.
    382  */
    383 
    384 void
    385 exit(exitstatus) {
    386 	_exit(exitstatus);
    387 }
    388 #endif
    389