1 /* $NetBSD: main.c,v 1.57 2011/06/18 21:18:46 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. 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\ 38 The Regents of the University of California. All rights reserved."); 39 #endif /* not lint */ 40 41 #ifndef lint 42 #if 0 43 static char sccsid[] = "@(#)main.c 8.7 (Berkeley) 7/19/95"; 44 #else 45 __RCSID("$NetBSD: main.c,v 1.57 2011/06/18 21:18:46 christos 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 <stdlib.h> 55 #include <locale.h> 56 #include <fcntl.h> 57 58 59 #include "shell.h" 60 #include "main.h" 61 #include "mail.h" 62 #include "options.h" 63 #include "builtins.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 int posix; 86 #if PROFILE 87 short profile_buf[16384]; 88 extern int etext(); 89 #endif 90 91 STATIC void read_profile(const char *); 92 STATIC char *find_dot_file(char *); 93 int main(int, 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(int argc, char **argv) 105 { 106 struct jmploc jmploc; 107 struct stackmark smark; 108 volatile int state; 109 char *shinit; 110 111 setlocale(LC_ALL, ""); 112 113 posix = getenv("POSIXLY_CORRECT") != NULL; 114 #if PROFILE 115 monitor(4, etext, profile_buf, sizeof profile_buf, 50); 116 #endif 117 state = 0; 118 if (setjmp(jmploc.loc)) { 119 /* 120 * When a shell procedure is executed, we raise the 121 * exception EXSHELLPROC to clean up before executing 122 * the shell procedure. 123 */ 124 switch (exception) { 125 case EXSHELLPROC: 126 rootpid = getpid(); 127 rootshell = 1; 128 minusc = NULL; 129 state = 3; 130 break; 131 132 case EXEXEC: 133 exitstatus = exerrno; 134 break; 135 136 case EXERROR: 137 exitstatus = 2; 138 break; 139 140 default: 141 break; 142 } 143 144 if (exception != EXSHELLPROC) { 145 if (state == 0 || iflag == 0 || ! rootshell) 146 exitshell(exitstatus); 147 } 148 reset(); 149 if (exception == EXINT 150 #if ATTY 151 && (! attyset() || equal(termval(), "emacs")) 152 #endif 153 ) { 154 out2c('\n'); 155 flushout(&errout); 156 } 157 popstackmark(&smark); 158 FORCEINTON; /* enable interrupts */ 159 if (state == 1) 160 goto state1; 161 else if (state == 2) 162 goto state2; 163 else if (state == 3) 164 goto state3; 165 else 166 goto state4; 167 } 168 handler = &jmploc; 169 #ifdef DEBUG 170 #if DEBUG == 2 171 debug = 1; 172 #endif 173 opentrace(); 174 trputs("Shell args: "); trargs(argv); 175 #endif 176 rootpid = getpid(); 177 rootshell = 1; 178 init(); 179 initpwd(); 180 setstackmark(&smark); 181 procargs(argc, argv); 182 if (argv[0] && argv[0][0] == '-') { 183 state = 1; 184 read_profile("/etc/profile"); 185 state1: 186 state = 2; 187 read_profile(".profile"); 188 } 189 state2: 190 state = 3; 191 if ((iflag || !posix) && 192 getuid() == geteuid() && getgid() == getegid()) { 193 if ((shinit = lookupvar("ENV")) != NULL && *shinit != '\0') { 194 state = 3; 195 read_profile(shinit); 196 } 197 } 198 state3: 199 state = 4; 200 if (sflag == 0 || minusc) { 201 static int sigs[] = { 202 SIGINT, SIGQUIT, SIGHUP, 203 #ifdef SIGTSTP 204 SIGTSTP, 205 #endif 206 SIGPIPE 207 }; 208 #define SIGSSIZE (sizeof(sigs)/sizeof(sigs[0])) 209 size_t i; 210 211 for (i = 0; i < SIGSSIZE; i++) 212 setsignal(sigs[i], 0); 213 } 214 215 if (minusc) 216 evalstring(minusc, 0); 217 218 if (sflag || minusc == NULL) { 219 state4: /* XXX ??? - why isn't this before the "if" statement */ 220 cmdloop(1); 221 } 222 #if PROFILE 223 monitor(0); 224 #endif 225 exitshell(exitstatus); 226 /* NOTREACHED */ 227 } 228 229 230 /* 231 * Read and execute commands. "Top" is nonzero for the top level command 232 * loop; it turns on prompting if the shell is interactive. 233 */ 234 235 void 236 cmdloop(int top) 237 { 238 union node *n; 239 struct stackmark smark; 240 int inter; 241 int numeof = 0; 242 243 TRACE(("cmdloop(%d) called\n", top)); 244 setstackmark(&smark); 245 for (;;) { 246 if (pendingsigs) 247 dotrap(); 248 inter = 0; 249 if (iflag == 1 && top) { 250 inter = 1; 251 showjobs(out2, SHOW_CHANGED); 252 chkmail(0); 253 flushout(&errout); 254 } 255 n = parsecmd(inter); 256 /* showtree(n); DEBUG */ 257 if (n == NEOF) { 258 if (!top || numeof >= 50) 259 break; 260 if (!stoppedjobs()) { 261 if (!Iflag) 262 break; 263 out2str("\nUse \"exit\" to leave shell.\n"); 264 } 265 numeof++; 266 } else if (n != NULL && nflag == 0) { 267 job_warning = (job_warning == 2) ? 1 : 0; 268 numeof = 0; 269 evaltree(n, 0); 270 } 271 popstackmark(&smark); 272 setstackmark(&smark); 273 if (evalskip == SKIPFILE) { 274 evalskip = 0; 275 break; 276 } 277 } 278 popstackmark(&smark); 279 } 280 281 282 283 /* 284 * Read /etc/profile or .profile. Return on error. 285 */ 286 287 STATIC void 288 read_profile(const char *name) 289 { 290 int fd; 291 int xflag_set = 0; 292 int vflag_set = 0; 293 294 INTOFF; 295 if ((fd = open(name, O_RDONLY)) >= 0) 296 setinputfd(fd, 1); 297 INTON; 298 if (fd < 0) 299 return; 300 /* -q turns off -x and -v just when executing init files */ 301 if (qflag) { 302 if (xflag) 303 xflag = 0, xflag_set = 1; 304 if (vflag) 305 vflag = 0, vflag_set = 1; 306 } 307 cmdloop(0); 308 if (qflag) { 309 if (xflag_set) 310 xflag = 1; 311 if (vflag_set) 312 vflag = 1; 313 } 314 popfile(); 315 } 316 317 318 319 /* 320 * Read a file containing shell functions. 321 */ 322 323 void 324 readcmdfile(char *name) 325 { 326 int fd; 327 328 INTOFF; 329 if ((fd = open(name, O_RDONLY)) >= 0) 330 setinputfd(fd, 1); 331 else 332 error("Can't open %s", name); 333 INTON; 334 cmdloop(0); 335 popfile(); 336 } 337 338 339 340 /* 341 * Take commands from a file. To be compatible we should do a path 342 * search for the file, which is necessary to find sub-commands. 343 */ 344 345 346 STATIC char * 347 find_dot_file(char *basename) 348 { 349 char *fullname; 350 const char *path = pathval(); 351 struct stat statb; 352 353 /* don't try this for absolute or relative paths */ 354 if (strchr(basename, '/')) 355 return basename; 356 357 while ((fullname = padvance(&path, basename)) != NULL) { 358 if ((stat(fullname, &statb) == 0) && S_ISREG(statb.st_mode)) { 359 /* 360 * Don't bother freeing here, since it will 361 * be freed by the caller. 362 */ 363 return fullname; 364 } 365 stunalloc(fullname); 366 } 367 368 /* not found in the PATH */ 369 error("%s: not found", basename); 370 /* NOTREACHED */ 371 } 372 373 int 374 dotcmd(int argc, char **argv) 375 { 376 exitstatus = 0; 377 378 if (argc >= 2) { /* That's what SVR2 does */ 379 char *fullname; 380 struct stackmark smark; 381 382 setstackmark(&smark); 383 fullname = find_dot_file(argv[1]); 384 setinputfile(fullname, 1); 385 commandname = fullname; 386 cmdloop(0); 387 popfile(); 388 popstackmark(&smark); 389 } 390 return exitstatus; 391 } 392 393 394 int 395 exitcmd(int argc, char **argv) 396 { 397 if (stoppedjobs()) 398 return 0; 399 if (argc > 1) 400 exitstatus = number(argv[1]); 401 exitshell(exitstatus); 402 /* NOTREACHED */ 403 } 404