1 /* $NetBSD: main.c,v 1.56 2010/02/21 09:54:57 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 1.56 2010/02/21 09:54:57 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 "output.h" 64 #include "parser.h" 65 #include "nodes.h" 66 #include "expand.h" 67 #include "eval.h" 68 #include "jobs.h" 69 #include "input.h" 70 #include "trap.h" 71 #include "var.h" 72 #include "show.h" 73 #include "memalloc.h" 74 #include "error.h" 75 #include "init.h" 76 #include "mystring.h" 77 #include "exec.h" 78 #include "cd.h" 79 80 #define PROFILE 0 81 82 int rootpid; 83 int rootshell; 84 int posix; 85 #if PROFILE 86 short profile_buf[16384]; 87 extern int etext(); 88 #endif 89 90 STATIC void read_profile(const char *); 91 STATIC char *find_dot_file(char *); 92 int main(int, char **); 93 94 /* 95 * Main routine. We initialize things, parse the arguments, execute 96 * profiles if we're a login shell, and then call cmdloop to execute 97 * commands. The setjmp call sets up the location to jump to when an 98 * exception occurs. When an exception occurs the variable "state" 99 * is used to figure out how far we had gotten. 100 */ 101 102 int 103 main(int argc, char **argv) 104 { 105 struct jmploc jmploc; 106 struct stackmark smark; 107 volatile int state; 108 char *shinit; 109 110 setlocale(LC_ALL, ""); 111 112 posix = getenv("POSIXLY_CORRECT") != NULL; 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 switch (exception) { 124 case EXSHELLPROC: 125 rootpid = getpid(); 126 rootshell = 1; 127 minusc = NULL; 128 state = 3; 129 break; 130 131 case EXEXEC: 132 exitstatus = exerrno; 133 break; 134 135 case EXERROR: 136 exitstatus = 2; 137 break; 138 139 default: 140 break; 141 } 142 143 if (exception != EXSHELLPROC) { 144 if (state == 0 || iflag == 0 || ! rootshell) 145 exitshell(exitstatus); 146 } 147 reset(); 148 if (exception == EXINT 149 #if ATTY 150 && (! attyset() || equal(termval(), "emacs")) 151 #endif 152 ) { 153 out2c('\n'); 154 flushout(&errout); 155 } 156 popstackmark(&smark); 157 FORCEINTON; /* enable interrupts */ 158 if (state == 1) 159 goto state1; 160 else if (state == 2) 161 goto state2; 162 else if (state == 3) 163 goto state3; 164 else 165 goto state4; 166 } 167 handler = &jmploc; 168 #ifdef DEBUG 169 #if DEBUG == 2 170 debug = 1; 171 #endif 172 opentrace(); 173 trputs("Shell args: "); trargs(argv); 174 #endif 175 rootpid = getpid(); 176 rootshell = 1; 177 init(); 178 initpwd(); 179 setstackmark(&smark); 180 procargs(argc, argv); 181 if (argv[0] && argv[0][0] == '-') { 182 state = 1; 183 read_profile("/etc/profile"); 184 state1: 185 state = 2; 186 read_profile(".profile"); 187 } 188 state2: 189 state = 3; 190 if ((iflag || !posix) && 191 getuid() == geteuid() && getgid() == getegid()) { 192 if ((shinit = lookupvar("ENV")) != NULL && *shinit != '\0') { 193 state = 3; 194 read_profile(shinit); 195 } 196 } 197 state3: 198 state = 4; 199 if (sflag == 0 || minusc) { 200 static int sigs[] = { 201 SIGINT, SIGQUIT, SIGHUP, 202 #ifdef SIGTSTP 203 SIGTSTP, 204 #endif 205 SIGPIPE 206 }; 207 #define SIGSSIZE (sizeof(sigs)/sizeof(sigs[0])) 208 size_t i; 209 210 for (i = 0; i < SIGSSIZE; i++) 211 setsignal(sigs[i], 0); 212 } 213 214 if (minusc) 215 evalstring(minusc, 0); 216 217 if (sflag || minusc == NULL) { 218 state4: /* XXX ??? - why isn't this before the "if" statement */ 219 cmdloop(1); 220 } 221 #if PROFILE 222 monitor(0); 223 #endif 224 exitshell(exitstatus); 225 /* NOTREACHED */ 226 } 227 228 229 /* 230 * Read and execute commands. "Top" is nonzero for the top level command 231 * loop; it turns on prompting if the shell is interactive. 232 */ 233 234 void 235 cmdloop(int top) 236 { 237 union node *n; 238 struct stackmark smark; 239 int inter; 240 int numeof = 0; 241 242 TRACE(("cmdloop(%d) called\n", top)); 243 setstackmark(&smark); 244 for (;;) { 245 if (pendingsigs) 246 dotrap(); 247 inter = 0; 248 if (iflag == 1 && top) { 249 inter = 1; 250 showjobs(out2, SHOW_CHANGED); 251 chkmail(0); 252 flushout(&errout); 253 } 254 n = parsecmd(inter); 255 /* showtree(n); DEBUG */ 256 if (n == NEOF) { 257 if (!top || numeof >= 50) 258 break; 259 if (!stoppedjobs()) { 260 if (!Iflag) 261 break; 262 out2str("\nUse \"exit\" to leave shell.\n"); 263 } 264 numeof++; 265 } else if (n != NULL && nflag == 0) { 266 job_warning = (job_warning == 2) ? 1 : 0; 267 numeof = 0; 268 evaltree(n, 0); 269 } 270 popstackmark(&smark); 271 setstackmark(&smark); 272 if (evalskip == SKIPFILE) { 273 evalskip = 0; 274 break; 275 } 276 } 277 popstackmark(&smark); 278 } 279 280 281 282 /* 283 * Read /etc/profile or .profile. Return on error. 284 */ 285 286 STATIC void 287 read_profile(const char *name) 288 { 289 int fd; 290 int xflag_set = 0; 291 int vflag_set = 0; 292 293 INTOFF; 294 if ((fd = open(name, O_RDONLY)) >= 0) 295 setinputfd(fd, 1); 296 INTON; 297 if (fd < 0) 298 return; 299 /* -q turns off -x and -v just when executing init files */ 300 if (qflag) { 301 if (xflag) 302 xflag = 0, xflag_set = 1; 303 if (vflag) 304 vflag = 0, vflag_set = 1; 305 } 306 cmdloop(0); 307 if (qflag) { 308 if (xflag_set) 309 xflag = 1; 310 if (vflag_set) 311 vflag = 1; 312 } 313 popfile(); 314 } 315 316 317 318 /* 319 * Read a file containing shell functions. 320 */ 321 322 void 323 readcmdfile(char *name) 324 { 325 int fd; 326 327 INTOFF; 328 if ((fd = open(name, O_RDONLY)) >= 0) 329 setinputfd(fd, 1); 330 else 331 error("Can't open %s", name); 332 INTON; 333 cmdloop(0); 334 popfile(); 335 } 336 337 338 339 /* 340 * Take commands from a file. To be compatible we should do a path 341 * search for the file, which is necessary to find sub-commands. 342 */ 343 344 345 STATIC char * 346 find_dot_file(char *basename) 347 { 348 char *fullname; 349 const char *path = pathval(); 350 struct stat statb; 351 352 /* don't try this for absolute or relative paths */ 353 if (strchr(basename, '/')) 354 return basename; 355 356 while ((fullname = padvance(&path, basename)) != NULL) { 357 if ((stat(fullname, &statb) == 0) && S_ISREG(statb.st_mode)) { 358 /* 359 * Don't bother freeing here, since it will 360 * be freed by the caller. 361 */ 362 return fullname; 363 } 364 stunalloc(fullname); 365 } 366 367 /* not found in the PATH */ 368 error("%s: not found", basename); 369 /* NOTREACHED */ 370 } 371 372 int 373 dotcmd(int argc, char **argv) 374 { 375 exitstatus = 0; 376 377 if (argc >= 2) { /* That's what SVR2 does */ 378 char *fullname; 379 struct stackmark smark; 380 381 setstackmark(&smark); 382 fullname = find_dot_file(argv[1]); 383 setinputfile(fullname, 1); 384 commandname = fullname; 385 cmdloop(0); 386 popfile(); 387 popstackmark(&smark); 388 } 389 return exitstatus; 390 } 391 392 393 int 394 exitcmd(int argc, char **argv) 395 { 396 if (stoppedjobs()) 397 return 0; 398 if (argc > 1) 399 exitstatus = number(argv[1]); 400 exitshell(exitstatus); 401 /* NOTREACHED */ 402 } 403