1 /*- 2 * SPDX-License-Identifier: BSD-3-Clause 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 #ifndef lint 36 static char const copyright[] = 37 "@(#) Copyright (c) 1991, 1993\n\ 38 The Regents of the University of California. All rights reserved.\n"; 39 #endif /* not lint */ 40 41 #ifndef lint 42 #if 0 43 static char sccsid[] = "@(#)main.c 8.6 (Berkeley) 5/28/95"; 44 #endif 45 #endif /* not lint */ 46 #include <sys/cdefs.h> 47 __FBSDID("$FreeBSD$"); 48 49 #include <stdio.h> 50 #include <signal.h> 51 #include <sys/stat.h> 52 #include <unistd.h> 53 #include <fcntl.h> 54 #include <locale.h> 55 #include <errno.h> 56 57 #include "shell.h" 58 #include "main.h" 59 #include "mail.h" 60 #include "options.h" 61 #include "output.h" 62 #include "parser.h" 63 #include "nodes.h" 64 #include "expand.h" 65 #include "eval.h" 66 #include "jobs.h" 67 #include "input.h" 68 #include "trap.h" 69 #include "var.h" 70 #include "show.h" 71 #include "memalloc.h" 72 #include "error.h" 73 #include "mystring.h" 74 #include "exec.h" 75 #include "cd.h" 76 #include "redir.h" 77 #include "builtins.h" 78 #ifndef NO_HISTORY 79 #include "myhistedit.h" 80 #endif 81 82 int rootpid; 83 int rootshell; 84 struct jmploc main_handler; 85 int localeisutf8, initial_localeisutf8; 86 87 static void reset(void); 88 static void cmdloop(int); 89 static void read_profile(const char *); 90 static char *find_dot_file(char *); 91 92 /* 93 * Main routine. We initialize things, parse the arguments, execute 94 * profiles if we're a login shell, and then call cmdloop to execute 95 * commands. The setjmp call sets up the location to jump to when an 96 * exception occurs. When an exception occurs the variable "state" 97 * is used to figure out how far we had gotten. 98 */ 99 100 int 101 main(int argc, char *argv[]) 102 { 103 /* 104 * As smark is accessed after a longjmp, it cannot be a local in main(). 105 * The C standard specifies that the values of non-volatile local 106 * variables are unspecified after a jump if modified between the 107 * setjmp and longjmp. 108 */ 109 static struct stackmark smark, smark2; 110 volatile int state; 111 char *shinit; 112 113 (void) setlocale(LC_ALL, ""); 114 initcharset(); 115 state = 0; 116 if (setjmp(main_handler.loc)) { 117 if (state == 0 || iflag == 0 || ! rootshell || 118 exception == EXEXIT) 119 exitshell(exitstatus); 120 reset(); 121 if (exception == EXINT) 122 out2fmt_flush("\n"); 123 popstackmark(&smark); 124 FORCEINTON; /* enable interrupts */ 125 if (state == 1) 126 goto state1; 127 else if (state == 2) 128 goto state2; 129 else if (state == 3) 130 goto state3; 131 else 132 goto state4; 133 } 134 handler = &main_handler; 135 #ifdef DEBUG 136 opentrace(); 137 trputs("Shell args: "); trargs(argv); 138 #endif 139 rootpid = getpid(); 140 rootshell = 1; 141 INTOFF; 142 initvar(); 143 setstackmark(&smark); 144 setstackmark(&smark2); 145 procargs(argc, argv); 146 trap_init(); 147 pwd_init(iflag); 148 INTON; 149 if (iflag) 150 chkmail(1); 151 if (argv[0] && argv[0][0] == '-') { 152 state = 1; 153 read_profile("/etc/profile"); 154 state1: 155 state = 2; 156 if (privileged == 0) 157 read_profile("${HOME-}/.profile"); 158 else 159 read_profile("/etc/suid_profile"); 160 } 161 state2: 162 state = 3; 163 if (!privileged && iflag) { 164 if ((shinit = lookupvar("ENV")) != NULL && *shinit != '\0') { 165 state = 3; 166 read_profile(shinit); 167 } 168 } 169 #ifndef NO_HISTORY 170 if (iflag) 171 histload(); 172 #endif 173 state3: 174 state = 4; 175 popstackmark(&smark2); 176 if (minusc) { 177 evalstring(minusc, sflag ? 0 : EV_EXIT); 178 } 179 state4: 180 if (sflag || minusc == NULL) { 181 cmdloop(1); 182 } 183 exitshell(exitstatus); 184 /*NOTREACHED*/ 185 return 0; 186 } 187 188 static void 189 reset(void) 190 { 191 reseteval(); 192 resetinput(); 193 } 194 195 /* 196 * Read and execute commands. "Top" is nonzero for the top level command 197 * loop; it turns on prompting if the shell is interactive. 198 */ 199 200 static void 201 cmdloop(int top) 202 { 203 union node *n; 204 struct stackmark smark; 205 int inter; 206 int numeof = 0; 207 208 TRACE(("cmdloop(%d) called\n", top)); 209 setstackmark(&smark); 210 for (;;) { 211 if (pendingsig) 212 dotrap(); 213 inter = 0; 214 if (iflag && top) { 215 inter++; 216 showjobs(1, SHOWJOBS_DEFAULT); 217 chkmail(0); 218 flushout(&output); 219 } 220 n = parsecmd(inter); 221 /* showtree(n); DEBUG */ 222 if (n == NEOF) { 223 if (!top || numeof >= 50) 224 break; 225 if (!stoppedjobs()) { 226 if (!Iflag) 227 break; 228 out2fmt_flush("\nUse \"exit\" to leave shell.\n"); 229 } 230 numeof++; 231 } else if (n != NULL && nflag == 0) { 232 job_warning = (job_warning == 2) ? 1 : 0; 233 numeof = 0; 234 evaltree(n, 0); 235 } 236 popstackmark(&smark); 237 setstackmark(&smark); 238 if (evalskip != 0) { 239 if (evalskip == SKIPRETURN) 240 evalskip = 0; 241 break; 242 } 243 } 244 popstackmark(&smark); 245 if (top && iflag) { 246 out2c('\n'); 247 flushout(out2); 248 } 249 } 250 251 252 253 /* 254 * Read /etc/profile or .profile. Return on error. 255 */ 256 257 static void 258 read_profile(const char *name) 259 { 260 int fd; 261 const char *expandedname; 262 int oflags = O_RDONLY | O_CLOEXEC; 263 264 if (verifyflag) 265 oflags |= O_VERIFY; 266 267 expandedname = expandstr(name); 268 if (expandedname == NULL) 269 return; 270 INTOFF; 271 if ((fd = open(expandedname, oflags)) >= 0) 272 setinputfd(fd, 1); 273 INTON; 274 if (fd < 0) 275 return; 276 cmdloop(0); 277 popfile(); 278 } 279 280 281 282 /* 283 * Read a file containing shell functions. 284 */ 285 286 void 287 readcmdfile(const char *name, int verify) 288 { 289 setinputfile(name, 1, verify); 290 cmdloop(0); 291 popfile(); 292 } 293 294 295 296 /* 297 * Take commands from a file. To be compatible we should do a path 298 * search for the file, which is necessary to find sub-commands. 299 */ 300 301 302 static char * 303 find_dot_file(char *basename) 304 { 305 char *fullname; 306 const char *opt; 307 const char *path = pathval(); 308 struct stat statb; 309 310 /* don't try this for absolute or relative paths */ 311 if( strchr(basename, '/')) 312 return basename; 313 314 while ((fullname = padvance(&path, &opt, basename)) != NULL) { 315 if ((stat(fullname, &statb) == 0) && S_ISREG(statb.st_mode)) { 316 /* 317 * Don't bother freeing here, since it will 318 * be freed by the caller. 319 */ 320 return fullname; 321 } 322 stunalloc(fullname); 323 } 324 return basename; 325 } 326 327 int 328 dotcmd(int argc, char **argv) 329 { 330 char *filename, *fullname; 331 332 if (argc < 2) 333 error("missing filename"); 334 335 exitstatus = 0; 336 337 /* 338 * Because we have historically not supported any options, 339 * only treat "--" specially. 340 */ 341 filename = argc > 2 && strcmp(argv[1], "--") == 0 ? argv[2] : argv[1]; 342 343 fullname = find_dot_file(filename); 344 setinputfile(fullname, 1, -1 /* verify */); 345 commandname = fullname; 346 cmdloop(0); 347 popfile(); 348 return exitstatus; 349 } 350 351 352 int 353 exitcmd(int argc, char **argv) 354 { 355 if (stoppedjobs()) 356 return 0; 357 if (argc > 1) 358 exitshell(number(argv[1])); 359 else 360 exitshell_savedstatus(); 361 } 362