commands/ash/main.c

   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
  34 static 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
  41 static char sccsid[] = "@(#)main.c      8.6 (Berkeley) 5/28/95";
  42 #endif
  43 #endif /* not lint */
  44 /*
  45 #include <sys/cdefs.h>
  46 __FBSDID("$FreeBSD: src/bin/sh/main.c,v 1.26 2004/04/06 20:06:51 markm Exp $");
  47 */
  48
  49 #include <stdio.h>
  50 #include <signal.h>
  51 #include <sys/stat.h>
  52 #include <unistd.h>
  53 #include <fcntl.h>
  54 #include <locale.h>
  55 #include <errno.h>
  56
  57 #include "shell.h"
  58 #include "main.h"
  59 #include "mail.h"
  60 #include "options.h"
  61 #include "output.h"
  62 #include "parser.h"
  63 #include "nodes.h"
  64 #include "expand.h"
  65 #include "eval.h"
  66 #include "jobs.h"
  67 #include "input.h"
  68 #include "trap.h"
  69 #include "var.h"
  70 #include "show.h"
  71 #include "memalloc.h"
  72 #include "error.h"
  73 #include "init.h"
  74 #include "mystring.h"
  75 #include "exec.h"
  76 #include "cd.h"
  77 #include "builtins.h"
  78
  79 int rootpid;
  80 int rootshell;
  81
  82 STATIC void read_profile(char *);
  83 STATIC char *find_dot_file(char *);
  84
  85 /*
  86  * Main routine.  We initialize things, parse the arguments, execute
  87  * profiles if we're a login shell, and then call cmdloop to execute
  88  * commands.  The setjmp call sets up the location to jump to when an
  89  * exception occurs.  When an exception occurs the variable "state"
  90  * is used to figure out how far we had gotten.
  91  */
  92
  93 int
  94 main(int argc, char *argv[])
  95 {
  96         struct jmploc jmploc;
  97         struct stackmark smark;
  98         volatile int state;
  99         char *shinit;
 100
 101         (void) setlocale(LC_ALL, "");
 102         state = 0;
 103         if (setjmp(jmploc.loc)) {
 104                 /*
 105                  * When a shell procedure is executed, we raise the
 106                  * exception EXSHELLPROC to clean up before executing
 107                  * the shell procedure.
 108                  */
 109                 switch (exception) {
 110                 case EXSHELLPROC:
 111                         rootpid = getpid();
 112                         rootshell = 1;
 113                         minusc = NULL;
 114                         state = 3;
 115                         break;
 116
 117                 case EXEXEC:
 118                         exitstatus = exerrno;
 119                         break;
 120
 121                 case EXERROR:
 122                         exitstatus = 2;
 123                         break;
 124
 125                 default:
 126                         break;
 127                 }
 128
 129                 if (exception != EXSHELLPROC) {
 130                     if (state == 0 || iflag == 0 || ! rootshell)
 131                             exitshell(exitstatus);
 132                 }
 133                 reset();
 134                 if (exception == EXINT) {
 135                         out2c('\n');
 136                         flushout(&errout);
 137                 }
 138                 popstackmark(&smark);
 139                 FORCEINTON;                             /* enable interrupts */
 140                 if (state == 1)
 141                         goto state1;
 142                 else if (state == 2)
 143                         goto state2;
 144                 else if (state == 3)
 145                         goto state3;
 146                 else
 147                         goto state4;
 148         }
 149         handler = &jmploc;
 150 #if DEBUG
 151         opentrace();
 152         trputs("Shell args:  ");  trargs(argv);
 153 #endif
 154         rootpid = getpid();
 155         rootshell = 1;
 156         init();
 157         setstackmark(&smark);
 158         procargs(argc, argv);
 159         if (getpwd() == NULL && iflag)
 160                 out2str("sh: cannot determine working directory\n");
 161         if (argv[0] && argv[0][0] == '-') {
 162                 state = 1;
 163                 read_profile("/etc/profile");
 164 state1:
 165                 state = 2;
 166                 if (privileged == 0)
 167                         read_profile(".profile");
 168                 else
 169                         read_profile("/etc/suid_profile");
 170         }
 171 state2:
 172         state = 3;
 173         if (!privileged && iflag) {
 174                 if ((shinit = lookupvar("ENV")) != NULL && *shinit != '\0') {
 175                         state = 3;
 176                         read_profile(shinit);
 177                 }
 178         }
 179 state3:
 180         state = 4;
 181         if (minusc) {
 182                 evalstring(minusc);
 183         }
 184         if (sflag || minusc == NULL) {
 185 state4: /* XXX ??? - why isn't this before the "if" statement */
 186                 cmdloop(1);
 187         }
 188         exitshell(exitstatus);
 189         /*NOTREACHED*/
 190         return 0;
 191 }
 192
 193
 194 /*
 195  * Read and execute commands.  "Top" is nonzero for the top level command
 196  * loop; it turns on prompting if the shell is interactive.
 197  */
 198
 199 void
 200 cmdloop(int top)
 201 {
 202         union node *n;
 203         struct stackmark smark;
 204         int inter;
 205         int numeof = 0;
 206
 207         TRACE(("cmdloop(%d) called\n", top));
 208         setstackmark(&smark);
 209         for (;;) {
 210                 if (pendingsigs)
 211                         dotrap();
 212                 inter = 0;
 213                 if (iflag && top) {
 214                         inter++;
 215                         showjobs(1, 0, 0);
 216                         chkmail(0);
 217                         flushout(&output);
 218                 }
 219                 n = parsecmd(inter);
 220                 /* showtree(n); DEBUG */
 221                 if (n == NEOF) {
 222                         if (!top || numeof >= 50)
 223                                 break;
 224                         if (!stoppedjobs()) {
 225                                 if (!Iflag)
 226                                         break;
 227                                 out2str("\nUse \"exit\" to leave shell.\n");
 228                         }
 229                         numeof++;
 230                 } else if (n != NULL && nflag == 0) {
 231                         job_warning = (job_warning == 2) ? 1 : 0;
 232                         numeof = 0;
 233                         evaltree(n, 0);
 234                 }
 235                 popstackmark(&smark);
 236                 setstackmark(&smark);
 237                 if (evalskip == SKIPFILE) {
 238                         evalskip = 0;
 239                         break;
 240                 }
 241         }
 242         popstackmark(&smark);
 243 }
 244
 245
 246
 247 /*
 248  * Read /etc/profile or .profile.  Return on error.
 249  */
 250
 251 STATIC void
 252 read_profile(char *name)
 253 {
 254         int fd;
 255
 256         INTOFF;
 257         if ((fd = open(name, O_RDONLY)) >= 0)
 258                 setinputfd(fd, 1);
 259         INTON;
 260         if (fd < 0)
 261                 return;
 262         cmdloop(0);
 263         popfile();
 264 }
 265
 266
 267
 268 /*
 269  * Read a file containing shell functions.
 270  */
 271
 272 void
 273 readcmdfile(char *name)
 274 {
 275         int fd;
 276
 277         INTOFF;
 278         if ((fd = open(name, O_RDONLY)) >= 0)
 279                 setinputfd(fd, 1);
 280         else
 281                 error("Can't open %s: %s", name, strerror(errno));
 282         INTON;
 283         cmdloop(0);
 284         popfile();
 285 }
 286
 287
 288
 289 /*
 290  * Take commands from a file.  To be compatible we should do a path
 291  * search for the file, which is necessary to find sub-commands.
 292  */
 293
 294
 295 STATIC char *
 296 find_dot_file(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(int argc, char **argv)
 318 {
 319         struct strlist *sp;
 320         exitstatus = 0;
 321
 322         for (sp = cmdenviron; sp ; sp = sp->next)
 323                 setvareq(savestr(sp->text), VSTRFIXED|VTEXTFIXED);
 324
 325         if (argc >= 2) {                /* That's what SVR2 does */
 326                 char *fullname = find_dot_file(argv[1]);
 327
 328                 setinputfile(fullname, 1);
 329                 commandname = fullname;
 330                 cmdloop(0);
 331                 popfile();
 332         }
 333         return exitstatus;
 334 }
 335
 336
 337 int
 338 exitcmd(int argc, char **argv)
 339 {
 340         extern int oexitstatus;
 341
 342         if (stoppedjobs())
 343                 return 0;
 344         if (argc > 1)
 345                 exitstatus = number(argv[1]);
 346         else
 347                 exitstatus = oexitstatus;
 348         exitshell(exitstatus);
 349         /*NOTREACHED*/
 350         return 0;
 351 }
 352
 353 /*
 354  * $PchId: main.c,v 1.5 2006/05/22 12:03:02 philip Exp $
 355  */