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main.c revision 1.20 
      1 /*	$NetBSD: main.c,v 1.20 1995/05/28 18:09:48 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 #ifndef lint
     40 static char copyright[] =
     41 "@(#) 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	8.6 (Berkeley) 5/28/95";
     48 #else
     49 static char rcsid[] = "$NetBSD: main.c,v 1.20 1995/05/28 18:09:48 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 
     80 #define PROFILE 0
     81 
     82 int rootpid;
     83 int rootshell;
     84 STATIC union node *curcmd;
     85 STATIC union node *prevcmd;
     86 extern int errno;
     87 #if PROFILE
     88 short profile_buf[16384];
     89 extern int etext();
     90 #endif
     91 
     92 STATIC void read_profile __P((char *));
     93 STATIC char *find_dot_file __P((char *));
     94 
     95 /*
     96  * Main routine.  We initialize things, parse the arguments, execute
     97  * profiles if we're a login shell, and then call cmdloop to execute
     98  * commands.  The setjmp call sets up the location to jump to when an
     99  * exception occurs.  When an exception occurs the variable "state"
    100  * is used to figure out how far we had gotten.
    101  */
    102 
    103 int
    104 main(argc, argv)
    105 	int argc;
    106 	char **argv;
    107 {
    108 	struct jmploc jmploc;
    109 	struct stackmark smark;
    110 	volatile int state;
    111 	char *shinit;
    112 
    113 #if PROFILE
    114 	monitor(4, etext, profile_buf, sizeof profile_buf, 50);
    115 #endif
    116 	state = 0;
    117 	if (setjmp(jmploc.loc)) {
    118 		/*
    119 		 * When a shell procedure is executed, we raise the
    120 		 * exception EXSHELLPROC to clean up before executing
    121 		 * the shell procedure.
    122 		 */
    123 		if (exception == EXERROR)
    124 			exitstatus = 2;
    125 		if (exception == EXSHELLPROC) {
    126 			rootpid = getpid();
    127 			rootshell = 1;
    128 			minusc = NULL;
    129 			state = 3;
    130 		} else if (state == 0 || iflag == 0 || ! rootshell)
    131 			exitshell(2);
    132 		reset();
    133 		if (exception == EXINT
    134 #if ATTY
    135 		 && (! attyset() || equal(termval(), "emacs"))
    136 #endif
    137 		 ) {
    138 			out2c('\n');
    139 			flushout(&errout);
    140 		}
    141 		popstackmark(&smark);
    142 		FORCEINTON;				/* enable interrupts */
    143 		if (state == 1)
    144 			goto state1;
    145 		else if (state == 2)
    146 			goto state2;
    147 		else if (state == 3)
    148 			goto state3;
    149 		else
    150 			goto state4;
    151 	}
    152 	handler = &jmploc;
    153 #ifdef DEBUG
    154 	opentrace();
    155 	trputs("Shell args:  ");  trargs(argv);
    156 #endif
    157 	rootpid = getpid();
    158 	rootshell = 1;
    159 	init();
    160 	setstackmark(&smark);
    161 	procargs(argc, argv);
    162 	if (argv[0] && argv[0][0] == '-') {
    163 		state = 1;
    164 		read_profile("/etc/profile");
    165 state1:
    166 		state = 2;
    167 		read_profile(".profile");
    168 	}
    169 state2:
    170 	state = 3;
    171 	if (getuid() == geteuid() && getgid() == getegid()) {
    172 		if ((shinit = lookupvar("ENV")) != NULL && *shinit != '\0') {
    173 			state = 3;
    174 			read_profile(shinit);
    175 		}
    176 	}
    177 state3:
    178 	state = 4;
    179 	if (minusc) {
    180 		evalstring(minusc);
    181 	}
    182 	if (sflag || minusc == NULL) {
    183 state4:	/* XXX ??? - why isn't this before the "if" statement */
    184 		cmdloop(1);
    185 	}
    186 #if PROFILE
    187 	monitor(0);
    188 #endif
    189 	exitshell(exitstatus);
    190 	/*NOTREACHED*/
    191 	return 0;
    192 }
    193 
    194 
    195 /*
    196  * Read and execute commands.  "Top" is nonzero for the top level command
    197  * loop; it turns on prompting if the shell is interactive.
    198  */
    199 
    200 void
    201 cmdloop(top)
    202 	int top;
    203 {
    204 	union node *n;
    205 	struct stackmark smark;
    206 	int inter;
    207 	int numeof = 0;
    208 
    209 	TRACE(("cmdloop(%d) called\n", top));
    210 	setstackmark(&smark);
    211 	for (;;) {
    212 		if (pendingsigs)
    213 			dotrap();
    214 		inter = 0;
    215 		if (iflag && top) {
    216 			inter++;
    217 			showjobs(1);
    218 			chkmail(0);
    219 			flushout(&output);
    220 		}
    221 		n = parsecmd(inter);
    222 		/* showtree(n); DEBUG */
    223 		if (n == NEOF) {
    224 			if (!top || numeof >= 50)
    225 				break;
    226 			if (!stoppedjobs()) {
    227 				if (!Iflag)
    228 					break;
    229 				out2str("\nUse \"exit\" to leave shell.\n");
    230 			}
    231 			numeof++;
    232 		} else if (n != NULL && nflag == 0) {
    233 			job_warning = (job_warning == 2) ? 1 : 0;
    234 			numeof = 0;
    235 			evaltree(n, 0);
    236 		}
    237 		popstackmark(&smark);
    238 	}
    239 	popstackmark(&smark);		/* unnecessary */
    240 }
    241 
    242 
    243 
    244 /*
    245  * Read /etc/profile or .profile.  Return on error.
    246  */
    247 
    248 STATIC void
    249 read_profile(name)
    250 	char *name;
    251 	{
    252 	int fd;
    253 
    254 	INTOFF;
    255 	if ((fd = open(name, O_RDONLY)) >= 0)
    256 		setinputfd(fd, 1);
    257 	INTON;
    258 	if (fd < 0)
    259 		return;
    260 	cmdloop(0);
    261 	popfile();
    262 }
    263 
    264 
    265 
    266 /*
    267  * Read a file containing shell functions.
    268  */
    269 
    270 void
    271 readcmdfile(name)
    272 	char *name;
    273 {
    274 	int fd;
    275 
    276 	INTOFF;
    277 	if ((fd = open(name, O_RDONLY)) >= 0)
    278 		setinputfd(fd, 1);
    279 	else
    280 		error("Can't open %s", name);
    281 	INTON;
    282 	cmdloop(0);
    283 	popfile();
    284 }
    285 
    286 
    287 
    288 /*
    289  * Take commands from a file.  To be compatable we should do a path
    290  * search for the file, which is necessary to find sub-commands.
    291  */
    292 
    293 
    294 STATIC char *
    295 find_dot_file(basename)
    296 	char *basename;
    297 {
    298 	static char localname[FILENAME_MAX+1];
    299 	char *fullname;
    300 	char *path = pathval();
    301 	struct stat statb;
    302 
    303 	/* don't try this for absolute or relative paths */
    304 	if( strchr(basename, '/'))
    305 		return basename;
    306 
    307 	while ((fullname = padvance(&path, basename)) != NULL) {
    308 		strcpy(localname, fullname);
    309 		stunalloc(fullname);
    310 		if ((stat(fullname, &statb) == 0) && S_ISREG(statb.st_mode))
    311 			return localname;
    312 	}
    313 	return basename;
    314 }
    315 
    316 int
    317 dotcmd(argc, argv)
    318 	int argc;
    319 	char **argv;
    320 {
    321 	struct strlist *sp;
    322 	exitstatus = 0;
    323 
    324 	for (sp = cmdenviron; sp ; sp = sp->next)
    325 		setvareq(savestr(sp->text), VSTRFIXED|VTEXTFIXED);
    326 
    327 	if (argc >= 2) {		/* That's what SVR2 does */
    328 		char *fullname = find_dot_file(argv[1]);
    329 
    330 		setinputfile(fullname, 1);
    331 		commandname = fullname;
    332 		cmdloop(0);
    333 		popfile();
    334 	}
    335 	return exitstatus;
    336 }
    337 
    338 
    339 int
    340 exitcmd(argc, argv)
    341 	int argc;
    342 	char **argv;
    343 {
    344 	if (stoppedjobs())
    345 		return 0;
    346 	if (argc > 1)
    347 		exitstatus = number(argv[1]);
    348 	exitshell(exitstatus);
    349 	/*NOTREACHED*/
    350 	return 0;
    351 }
    352 
    353 
    354 #ifdef notdef
    355 /*
    356  * Should never be called.
    357  */
    358 
    359 void
    360 exit(exitstatus) {
    361 	_exit(exitstatus);
    362 }
    363 #endif
    364