1 /* $NetBSD: main.c,v 1.58 2014/05/31 14:42:18 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 1.58 2014/05/31 14:42:18 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 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 enum skipstate skip; 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); 273 274 /* 275 * Any SKIP* can occur here! SKIP(FUNC|BREAK|CONT) occur when 276 * a dotcmd is in a loop or a function body and appropriate 277 * built-ins occurs in file scope in the sourced file. Values 278 * other than SKIPFILE are reset by the appropriate eval*() 279 * that contained the dotcmd() call. 280 */ 281 skip = current_skipstate(); 282 if (skip != SKIPNONE) { 283 if (skip == SKIPFILE) 284 stop_skipping(); 285 break; 286 } 287 } 288 popstackmark(&smark); 289 } 290 291 292 293 /* 294 * Read /etc/profile or .profile. Return on error. 295 */ 296 297 STATIC void 298 read_profile(const char *name) 299 { 300 int fd; 301 int xflag_set = 0; 302 int vflag_set = 0; 303 304 INTOFF; 305 if ((fd = open(name, O_RDONLY)) >= 0) 306 setinputfd(fd, 1); 307 INTON; 308 if (fd < 0) 309 return; 310 /* -q turns off -x and -v just when executing init files */ 311 if (qflag) { 312 if (xflag) 313 xflag = 0, xflag_set = 1; 314 if (vflag) 315 vflag = 0, vflag_set = 1; 316 } 317 cmdloop(0); 318 if (qflag) { 319 if (xflag_set) 320 xflag = 1; 321 if (vflag_set) 322 vflag = 1; 323 } 324 popfile(); 325 } 326 327 328 329 /* 330 * Read a file containing shell functions. 331 */ 332 333 void 334 readcmdfile(char *name) 335 { 336 int fd; 337 338 INTOFF; 339 if ((fd = open(name, O_RDONLY)) >= 0) 340 setinputfd(fd, 1); 341 else 342 error("Can't open %s", name); 343 INTON; 344 cmdloop(0); 345 popfile(); 346 } 347 348 349 350 int 351 exitcmd(int argc, char **argv) 352 { 353 if (stoppedjobs()) 354 return 0; 355 if (argc > 1) 356 exitstatus = number(argv[1]); 357 exitshell(exitstatus); 358 /* NOTREACHED */ 359 } 360