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 * 3. All advertising materials mentioning features or use of this software 17 * must display the following acknowledgement: 18 * This product includes software developed by the University of 19 * California, Berkeley and its contributors. 20 * 4. Neither the name of the University nor the names of its contributors 21 * may be used to endorse or promote products derived from this software 22 * without specific prior written permission. 23 * 24 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 25 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 26 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 27 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 28 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 29 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 30 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 31 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 32 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 33 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 34 * SUCH DAMAGE. 35 * 36 * @(#) Copyright (c) 1991, 1993 The Regents of the University of California. All rights reserved. 37 * @(#)main.c 8.6 (Berkeley) 5/28/95 38 * $FreeBSD: src/bin/sh/main.c,v 1.45 2011/04/23 22:28:56 jilles Exp $ 39 */ 40 41 #include <stdio.h> 42 #include <signal.h> 43 #include <sys/stat.h> 44 #include <unistd.h> 45 #include <fcntl.h> 46 #include <locale.h> 47 #include <errno.h> 48 49 #include "shell.h" 50 #include "main.h" 51 #include "mail.h" 52 #include "options.h" 53 #include "output.h" 54 #include "parser.h" 55 #include "nodes.h" 56 #include "expand.h" 57 #include "eval.h" 58 #include "jobs.h" 59 #include "input.h" 60 #include "trap.h" 61 #include "var.h" 62 #include "show.h" 63 #include "memalloc.h" 64 #include "error.h" 65 #include "init.h" 66 #include "mystring.h" 67 #include "exec.h" 68 #include "cd.h" 69 70 int rootpid; 71 int rootshell; 72 struct jmploc main_handler; 73 74 static void read_profile(const char *); 75 static const char *find_dot_file(const char *); 76 77 /* 78 * Main routine. We initialize things, parse the arguments, execute 79 * profiles if we're a login shell, and then call cmdloop to execute 80 * commands. The setjmp call sets up the location to jump to when an 81 * exception occurs. When an exception occurs the variable "state" 82 * is used to figure out how far we had gotten. 83 */ 84 85 int 86 main(int argc, char *argv[]) 87 { 88 struct stackmark smark; 89 volatile int state; 90 char *shinit; 91 92 setlocale(LC_ALL, ""); 93 state = 0; 94 if (setjmp(main_handler.loc)) { 95 switch (exception) { 96 case EXEXEC: 97 exitstatus = exerrno; 98 break; 99 100 case EXERROR: 101 exitstatus = 2; 102 break; 103 104 default: 105 break; 106 } 107 108 if (state == 0 || iflag == 0 || ! rootshell || 109 exception == EXEXIT) 110 exitshell(exitstatus); 111 reset(); 112 if (exception == EXINT) 113 out2fmt_flush("\n"); 114 popstackmark(&smark); 115 FORCEINTON; /* enable interrupts */ 116 if (state == 1) 117 goto state1; 118 else if (state == 2) 119 goto state2; 120 else if (state == 3) 121 goto state3; 122 else 123 goto state4; 124 } 125 handler = &main_handler; 126 #ifdef DEBUG 127 opentrace(); 128 trputs("Shell args: "); trargs(argv); 129 #endif 130 rootpid = getpid(); 131 rootshell = 1; 132 init(); 133 setstackmark(&smark); 134 procargs(argc, argv); 135 pwd_init(iflag); 136 if (iflag) 137 chkmail(1); 138 if (argv[0] && argv[0][0] == '-') { 139 state = 1; 140 read_profile("/etc/profile"); 141 state1: 142 state = 2; 143 if (privileged == 0) 144 read_profile(".profile"); 145 else 146 read_profile("/etc/suid_profile"); 147 } 148 state2: 149 state = 3; 150 if (!privileged && iflag) { 151 if ((shinit = lookupvar("ENV")) != NULL && *shinit != '\0') { 152 state = 3; 153 read_profile(shinit); 154 } 155 } 156 state3: 157 state = 4; 158 if (minusc) { 159 evalstring(minusc, sflag ? 0 : EV_EXIT); 160 } 161 if (sflag || minusc == NULL) { 162 state4: /* XXX ??? - why isn't this before the "if" statement */ 163 cmdloop(1); 164 } 165 exitshell(exitstatus); 166 /*NOTREACHED*/ 167 return 0; 168 } 169 170 171 /* 172 * Read and execute commands. "Top" is nonzero for the top level command 173 * loop; it turns on prompting if the shell is interactive. 174 */ 175 176 void 177 cmdloop(int top) 178 { 179 union node *n; 180 struct stackmark smark; 181 int inter; 182 int numeof = 0; 183 184 TRACE(("cmdloop(%d) called\n", top)); 185 setstackmark(&smark); 186 for (;;) { 187 if (pendingsigs) 188 dotrap(); 189 inter = 0; 190 if (iflag && top) { 191 inter++; 192 showjobs(1, SHOWJOBS_DEFAULT); 193 chkmail(0); 194 flushout(&output); 195 } 196 n = parsecmd(inter); 197 /* showtree(n); DEBUG */ 198 if (n == NEOF) { 199 if (!top || numeof >= 50) 200 break; 201 if (!stoppedjobs()) { 202 if (!Iflag) 203 break; 204 out2fmt_flush("\nUse \"exit\" to leave shell.\n"); 205 } 206 numeof++; 207 } else if (n != NULL && nflag == 0) { 208 job_warning = (job_warning == 2) ? 1 : 0; 209 numeof = 0; 210 evaltree(n, 0); 211 } 212 popstackmark(&smark); 213 setstackmark(&smark); 214 if (evalskip != 0) { 215 if (evalskip == SKIPFILE) 216 evalskip = 0; 217 break; 218 } 219 } 220 popstackmark(&smark); 221 } 222 223 224 225 /* 226 * Read /etc/profile or .profile. Return on error. 227 */ 228 229 static void 230 read_profile(const char *name) 231 { 232 int fd; 233 234 INTOFF; 235 if ((fd = open(name, O_RDONLY)) >= 0) 236 setinputfd(fd, 1); 237 INTON; 238 if (fd < 0) 239 return; 240 cmdloop(0); 241 popfile(); 242 } 243 244 245 246 /* 247 * Read a file containing shell functions. 248 */ 249 250 void 251 readcmdfile(const char *name) 252 { 253 int fd; 254 255 INTOFF; 256 if ((fd = open(name, O_RDONLY)) >= 0) 257 setinputfd(fd, 1); 258 else 259 error("Can't open %s: %s", name, strerror(errno)); 260 INTON; 261 cmdloop(0); 262 popfile(); 263 } 264 265 266 267 /* 268 * Take commands from a file. To be compatible we should do a path 269 * search for the file, which is necessary to find sub-commands. 270 */ 271 272 273 static const char * 274 find_dot_file(const char *basename) 275 { 276 static char localname[FILENAME_MAX+1]; 277 char *fullname; 278 const char *path = pathval(); 279 struct stat statb; 280 281 /* don't try this for absolute or relative paths */ 282 if( strchr(basename, '/')) 283 return basename; 284 285 while ((fullname = padvance(&path, basename)) != NULL) { 286 strcpy(localname, fullname); 287 stunalloc(fullname); 288 if ((stat(fullname, &statb) == 0) && S_ISREG(statb.st_mode)) 289 return localname; 290 } 291 return basename; 292 } 293 294 int 295 dotcmd(int argc, char **argv) 296 { 297 const char *fullname; 298 char *filename; 299 300 if (argc < 2) 301 error("missing filename"); 302 303 exitstatus = 0; 304 305 /* 306 * Because we have historically not supported any options, 307 * only treat "--" specially. 308 */ 309 filename = argc > 2 && strcmp(argv[1], "--") == 0 ? argv[2] : argv[1]; 310 311 fullname = find_dot_file(filename); 312 setinputfile(fullname, 1); 313 commandname = fullname; 314 cmdloop(0); 315 popfile(); 316 return exitstatus; 317 } 318 319 320 int 321 exitcmd(int argc, char **argv) 322 { 323 if (stoppedjobs()) 324 return 0; 325 if (argc > 1) 326 exitshell(number(argv[1])); 327 else 328 exitshell_savedstatus(); 329 } 330