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