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 1.44 2011/02/04 22:47:55 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 exitshell(exitstatus); 110 reset(); 111 if (exception == EXINT) 112 out2fmt_flush("\n"); 113 popstackmark(&smark); 114 FORCEINTON; /* enable interrupts */ 115 if (state == 1) 116 goto state1; 117 else if (state == 2) 118 goto state2; 119 else if (state == 3) 120 goto state3; 121 else 122 goto state4; 123 } 124 handler = &main_handler; 125 #ifdef DEBUG 126 opentrace(); 127 trputs("Shell args: "); trargs(argv); 128 #endif 129 rootpid = getpid(); 130 rootshell = 1; 131 init(); 132 setstackmark(&smark); 133 procargs(argc, argv); 134 pwd_init(iflag); 135 if (iflag) 136 chkmail(1); 137 if (argv[0] && argv[0][0] == '-') { 138 state = 1; 139 read_profile("/etc/profile"); 140 state1: 141 state = 2; 142 if (privileged == 0) 143 read_profile(".profile"); 144 else 145 read_profile("/etc/suid_profile"); 146 } 147 state2: 148 state = 3; 149 if (!privileged && iflag) { 150 if ((shinit = lookupvar("ENV")) != NULL && *shinit != '\0') { 151 state = 3; 152 read_profile(shinit); 153 } 154 } 155 state3: 156 state = 4; 157 if (minusc) { 158 evalstring(minusc, sflag ? 0 : EV_EXIT); 159 } 160 if (sflag || minusc == NULL) { 161 state4: /* XXX ??? - why isn't this before the "if" statement */ 162 cmdloop(1); 163 } 164 exitshell(exitstatus); 165 /*NOTREACHED*/ 166 return 0; 167 } 168 169 170 /* 171 * Read and execute commands. "Top" is nonzero for the top level command 172 * loop; it turns on prompting if the shell is interactive. 173 */ 174 175 void 176 cmdloop(int top) 177 { 178 union node *n; 179 struct stackmark smark; 180 int inter; 181 int numeof = 0; 182 183 TRACE(("cmdloop(%d) called\n", top)); 184 setstackmark(&smark); 185 for (;;) { 186 if (pendingsigs) 187 dotrap(); 188 inter = 0; 189 if (iflag && top) { 190 inter++; 191 showjobs(1, SHOWJOBS_DEFAULT); 192 chkmail(0); 193 flushout(&output); 194 } 195 n = parsecmd(inter); 196 /* showtree(n); DEBUG */ 197 if (n == NEOF) { 198 if (!top || numeof >= 50) 199 break; 200 if (!stoppedjobs()) { 201 if (!Iflag) 202 break; 203 out2fmt_flush("\nUse \"exit\" to leave shell.\n"); 204 } 205 numeof++; 206 } else if (n != NULL && nflag == 0) { 207 job_warning = (job_warning == 2) ? 1 : 0; 208 numeof = 0; 209 evaltree(n, 0); 210 } 211 popstackmark(&smark); 212 setstackmark(&smark); 213 if (evalskip != 0) { 214 if (evalskip == SKIPFILE) 215 evalskip = 0; 216 break; 217 } 218 } 219 popstackmark(&smark); 220 } 221 222 223 224 /* 225 * Read /etc/profile or .profile. Return on error. 226 */ 227 228 static void 229 read_profile(const char *name) 230 { 231 int fd; 232 233 INTOFF; 234 if ((fd = open(name, O_RDONLY)) >= 0) 235 setinputfd(fd, 1); 236 INTON; 237 if (fd < 0) 238 return; 239 cmdloop(0); 240 popfile(); 241 } 242 243 244 245 /* 246 * Read a file containing shell functions. 247 */ 248 249 void 250 readcmdfile(const char *name) 251 { 252 int fd; 253 254 INTOFF; 255 if ((fd = open(name, O_RDONLY)) >= 0) 256 setinputfd(fd, 1); 257 else 258 error("Can't open %s: %s", name, strerror(errno)); 259 INTON; 260 cmdloop(0); 261 popfile(); 262 } 263 264 265 266 /* 267 * Take commands from a file. To be compatible we should do a path 268 * search for the file, which is necessary to find sub-commands. 269 */ 270 271 272 static const char * 273 find_dot_file(const char *basename) 274 { 275 static char localname[FILENAME_MAX+1]; 276 char *fullname; 277 const char *path = pathval(); 278 struct stat statb; 279 280 /* don't try this for absolute or relative paths */ 281 if( strchr(basename, '/')) 282 return basename; 283 284 while ((fullname = padvance(&path, basename)) != NULL) { 285 strcpy(localname, fullname); 286 stunalloc(fullname); 287 if ((stat(fullname, &statb) == 0) && S_ISREG(statb.st_mode)) 288 return localname; 289 } 290 return basename; 291 } 292 293 int 294 dotcmd(int argc, char **argv) 295 { 296 const char *fullname; 297 char *filename; 298 299 if (argc < 2) 300 error("missing filename"); 301 302 exitstatus = 0; 303 304 /* 305 * Because we have historically not supported any options, 306 * only treat "--" specially. 307 */ 308 filename = argc > 2 && strcmp(argv[1], "--") == 0 ? argv[2] : argv[1]; 309 310 fullname = find_dot_file(filename); 311 setinputfile(fullname, 1); 312 commandname = fullname; 313 cmdloop(0); 314 popfile(); 315 return exitstatus; 316 } 317 318 319 int 320 exitcmd(int argc, char **argv) 321 { 322 if (stoppedjobs()) 323 return 0; 324 if (argc > 1) 325 exitshell(number(argv[1])); 326 else 327 exitshell_savedstatus(); 328 } 329