main.c revision 1.2
1 /*- 2 * Copyright (c) 1991 The Regents of the University of California. 3 * 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 37 #ifndef lint 38 char copyright[] = 39 "@(#) Copyright (c) 1991 The Regents of the University of California.\n\ 40 All rights reserved.\n"; 41 #endif /* not lint */ 42 43 #ifndef lint 44 static char sccsid[] = "@(#)main.c 5.2 (Berkeley) 3/13/91"; 45 static char rcsid[] = "$Id: main.c,v 1.2 1993/03/22 08:04:00 cgd Exp $"; 46 #endif /* not lint */ 47 48 #include <signal.h> 49 #include <fcntl.h> 50 #include "shell.h" 51 #include "main.h" 52 #include "mail.h" 53 #include "options.h" 54 #include "output.h" 55 #include "parser.h" 56 #include "nodes.h" 57 #include "eval.h" 58 #include "jobs.h" 59 #include "input.h" 60 #include "trap.h" 61 #if ATTY 62 #include "var.h" 63 #endif 64 #include "memalloc.h" 65 #include "error.h" 66 #include "init.h" 67 #include "mystring.h" 68 69 #define PROFILE 0 70 71 int rootpid; 72 int rootshell; 73 STATIC union node *curcmd; 74 STATIC union node *prevcmd; 75 extern int errno; 76 #if PROFILE 77 short profile_buf[16384]; 78 extern int etext(); 79 #endif 80 81 #ifdef __STDC__ 82 STATIC void read_profile(char *); 83 char *getenv(char *); 84 #else 85 STATIC void read_profile(); 86 char *getenv(); 87 #endif 88 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 main(argc, argv) char **argv; { 99 struct jmploc jmploc; 100 struct stackmark smark; 101 volatile int state; 102 char *shinit; 103 104 #if PROFILE 105 monitor(4, etext, profile_buf, sizeof profile_buf, 50); 106 #endif 107 state = 0; 108 if (setjmp(jmploc.loc)) { 109 /* 110 * When a shell procedure is executed, we raise the 111 * exception EXSHELLPROC to clean up before executing 112 * the shell procedure. 113 */ 114 if (exception == EXSHELLPROC) { 115 rootpid = getpid(); 116 rootshell = 1; 117 minusc = NULL; 118 state = 3; 119 } else if (state == 0 || iflag == 0 || ! rootshell) 120 exitshell(2); 121 reset(); 122 #if ATTY 123 if (exception == EXINT 124 && (! attyset() || equal(termval(), "emacs"))) { 125 #else 126 if (exception == EXINT) { 127 #endif 128 out2c('\n'); 129 flushout(&errout); 130 } 131 popstackmark(&smark); 132 FORCEINTON; /* enable interrupts */ 133 if (state == 1) 134 goto state1; 135 else if (state == 2) 136 goto state2; 137 else 138 goto state3; 139 } 140 handler = &jmploc; 141 #ifdef DEBUG 142 opentrace(); 143 trputs("Shell args: "); trargs(argv); 144 #endif 145 rootpid = getpid(); 146 rootshell = 1; 147 init(); 148 setstackmark(&smark); 149 procargs(argc, argv); 150 if (argv[0] && argv[0][0] == '-') { 151 state = 1; 152 read_profile("/etc/profile"); 153 state1: 154 state = 2; 155 read_profile(".profile"); 156 } else if ((sflag || minusc) && (shinit = getenv("SHINIT")) != NULL) { 157 state = 2; 158 evalstring(shinit); 159 } 160 state2: 161 state = 3; 162 if (minusc) { 163 evalstring(minusc); 164 } 165 if (sflag || minusc == NULL) { 166 state3: 167 cmdloop(1); 168 } 169 #if PROFILE 170 monitor(0); 171 #endif 172 exitshell(exitstatus); 173 } 174 175 176 /* 177 * Read and execute commands. "Top" is nonzero for the top level command 178 * loop; it turns on prompting if the shell is interactive. 179 */ 180 181 void 182 cmdloop(top) { 183 union node *n; 184 struct stackmark smark; 185 int inter; 186 int numeof; 187 188 TRACE(("cmdloop(%d) called\n", top)); 189 setstackmark(&smark); 190 numeof = 0; 191 for (;;) { 192 if (pendingsigs) 193 dotrap(); 194 inter = 0; 195 if (iflag && top) { 196 inter++; 197 showjobs(1); 198 chkmail(0); 199 flushout(&output); 200 } 201 n = parsecmd(inter); 202 #ifdef DEBUG 203 /* showtree(n); */ 204 #endif 205 if (n == NEOF) { 206 if (Iflag == 0 || numeof >= 50) 207 break; 208 out2str("\nUse \"exit\" to leave shell.\n"); 209 numeof++; 210 } else if (n != NULL && nflag == 0) { 211 if (inter) { 212 INTOFF; 213 if (prevcmd) 214 freefunc(prevcmd); 215 prevcmd = curcmd; 216 curcmd = copyfunc(n); 217 INTON; 218 } 219 evaltree(n, 0); 220 #ifdef notdef 221 if (exitstatus) /*DEBUG*/ 222 outfmt(&errout, "Exit status 0x%X\n", exitstatus); 223 #endif 224 } 225 popstackmark(&smark); 226 } 227 popstackmark(&smark); /* unnecessary */ 228 } 229 230 231 232 /* 233 * Read /etc/profile or .profile. Return on error. 234 */ 235 236 STATIC void 237 read_profile(name) 238 char *name; 239 { 240 int fd; 241 242 INTOFF; 243 if ((fd = open(name, O_RDONLY)) >= 0) 244 setinputfd(fd, 1); 245 INTON; 246 if (fd < 0) 247 return; 248 cmdloop(0); 249 popfile(); 250 } 251 252 253 254 /* 255 * Read a file containing shell functions. 256 */ 257 258 void 259 readcmdfile(name) 260 char *name; 261 { 262 int fd; 263 264 INTOFF; 265 if ((fd = open(name, O_RDONLY)) >= 0) 266 setinputfd(fd, 1); 267 else 268 error("Can't open %s", name); 269 INTON; 270 cmdloop(0); 271 popfile(); 272 } 273 274 275 276 /* 277 * Take commands from a file. To be compatable we should do a path 278 * search for the file, but a path search doesn't make any sense. 279 */ 280 281 dotcmd(argc, argv) char **argv; { 282 exitstatus = 0; 283 if (argc >= 2) { /* That's what SVR2 does */ 284 setinputfile(argv[1], 1); 285 commandname = argv[1]; 286 cmdloop(0); 287 popfile(); 288 } 289 return exitstatus; 290 } 291 292 293 exitcmd(argc, argv) char **argv; { 294 if (argc > 1) 295 exitstatus = number(argv[1]); 296 exitshell(exitstatus); 297 } 298 299 300 lccmd(argc, argv) char **argv; { 301 if (argc > 1) { 302 defun(argv[1], prevcmd); 303 return 0; 304 } else { 305 INTOFF; 306 freefunc(curcmd); 307 curcmd = prevcmd; 308 prevcmd = NULL; 309 INTON; 310 evaltree(curcmd, 0); 311 return exitstatus; 312 } 313 } 314 315 316 317 #ifdef notdef 318 /* 319 * Should never be called. 320 */ 321 322 void 323 exit(exitstatus) { 324 _exit(exitstatus); 325 } 326 #endif 327
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