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