main.c revision 1.9
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 37 #ifndef lint 38 static char copyright[] = 39 "@(#) Copyright (c) 1991, 1993\n\ 40 The Regents of the University of California. All rights reserved.\n"; 41 #endif /* not lint */ 42 43 #ifndef lint 44 static char sccsid[] = "@(#)main.c 8.1 (Berkeley) 5/31/93"; 45 #endif /* not lint */ 46 47 #include <signal.h> 48 #include <fcntl.h> 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 "eval.h" 57 #include "jobs.h" 58 #include "input.h" 59 #include "trap.h" 60 #include "var.h" 61 #include "memalloc.h" 62 #include "error.h" 63 #include "init.h" 64 #include "mystring.h" 65 66 #define PROFILE 0 67 68 int rootpid; 69 int rootshell; 70 STATIC union node *curcmd; 71 STATIC union node *prevcmd; 72 extern int errno; 73 #if PROFILE 74 short profile_buf[16384]; 75 extern int etext(); 76 #endif 77 78 #ifdef __STDC__ 79 STATIC void read_profile(char *); 80 char *getenv(char *); 81 #else 82 STATIC void read_profile(); 83 char *getenv(); 84 #endif 85 86 87 /* 88 * Main routine. We initialize things, parse the arguments, execute 89 * profiles if we're a login shell, and then call cmdloop to execute 90 * commands. The setjmp call sets up the location to jump to when an 91 * exception occurs. When an exception occurs the variable "state" 92 * is used to figure out how far we had gotten. 93 */ 94 95 main(argc, argv) char **argv; { 96 struct jmploc jmploc; 97 struct stackmark smark; 98 volatile int state; 99 char *shinit; 100 101 #if PROFILE 102 monitor(4, etext, profile_buf, sizeof profile_buf, 50); 103 #endif 104 state = 0; 105 if (setjmp(jmploc.loc)) { 106 /* 107 * When a shell procedure is executed, we raise the 108 * exception EXSHELLPROC to clean up before executing 109 * the shell procedure. 110 */ 111 if (exception == EXSHELLPROC) { 112 rootpid = getpid(); 113 rootshell = 1; 114 minusc = NULL; 115 state = 3; 116 } else if (state == 0 || iflag == 0 || ! rootshell) 117 exitshell(2); 118 reset(); 119 if (exception == EXINT 120 #if ATTY 121 && (! attyset() || equal(termval(), "emacs")) 122 #endif 123 ) { 124 out2c('\n'); 125 flushout(&errout); 126 } 127 popstackmark(&smark); 128 FORCEINTON; /* enable interrupts */ 129 if (state == 1) 130 goto state1; 131 else if (state == 2) 132 goto state2; 133 else if (state == 3) 134 goto state3; 135 else 136 goto state4; 137 } 138 handler = &jmploc; 139 #ifdef DEBUG 140 opentrace(); 141 trputs("Shell args: "); trargs(argv); 142 #endif 143 rootpid = getpid(); 144 rootshell = 1; 145 init(); 146 setstackmark(&smark); 147 procargs(argc, argv); 148 if (argv[0] && argv[0][0] == '-') { 149 state = 1; 150 read_profile("/etc/profile"); 151 state1: 152 state = 2; 153 read_profile(".profile"); 154 } 155 state2: 156 state = 3; 157 if ((shinit = lookupvar("ENV")) != NULL && 158 *shinit != '\0') { 159 state = 3; 160 read_profile(shinit); 161 } 162 state3: 163 state = 4; 164 if (minusc) { 165 evalstring(minusc); 166 } 167 if (sflag || minusc == NULL) { 168 state4: /* XXX ??? - why isn't this before the "if" statement */ 169 cmdloop(1); 170 } 171 #if PROFILE 172 monitor(0); 173 #endif 174 exitshell(exitstatus); 175 } 176 177 178 /* 179 * Read and execute commands. "Top" is nonzero for the top level command 180 * loop; it turns on prompting if the shell is interactive. 181 */ 182 183 void 184 cmdloop(top) { 185 union node *n; 186 struct stackmark smark; 187 int inter; 188 int numeof = 0; 189 190 TRACE(("cmdloop(%d) called\n", top)); 191 setstackmark(&smark); 192 for (;;) { 193 if (pendingsigs) 194 dotrap(); 195 inter = 0; 196 if (iflag && top) { 197 inter++; 198 showjobs(1); 199 chkmail(0); 200 flushout(&output); 201 } 202 n = parsecmd(inter); 203 /* showtree(n); DEBUG */ 204 if (n == NEOF) { 205 if (!top || numeof >= 50) 206 break; 207 if (!stoppedjobs()) { 208 if (!Iflag) 209 break; 210 out2str("\nUse \"exit\" to leave shell.\n"); 211 } 212 numeof++; 213 } else if (n != NULL && nflag == 0) { 214 job_warning = (job_warning == 2) ? 1 : 0; 215 numeof = 0; 216 evaltree(n, 0); 217 } 218 popstackmark(&smark); 219 } 220 popstackmark(&smark); /* unnecessary */ 221 } 222 223 224 225 /* 226 * Read /etc/profile or .profile. Return on error. 227 */ 228 229 STATIC void 230 read_profile(name) 231 char *name; 232 { 233 int fd; 234 235 INTOFF; 236 if ((fd = open(name, O_RDONLY)) >= 0) 237 setinputfd(fd, 1); 238 INTON; 239 if (fd < 0) 240 return; 241 cmdloop(0); 242 popfile(); 243 } 244 245 246 247 /* 248 * Read a file containing shell functions. 249 */ 250 251 void 252 readcmdfile(name) 253 char *name; 254 { 255 int fd; 256 257 INTOFF; 258 if ((fd = open(name, O_RDONLY)) >= 0) 259 setinputfd(fd, 1); 260 else 261 error("Can't open %s", name); 262 INTON; 263 cmdloop(0); 264 popfile(); 265 } 266 267 268 269 /* 270 * Take commands from a file. To be compatable we should do a path 271 * search for the file, but a path search doesn't make any sense. 272 */ 273 274 dotcmd(argc, argv) char **argv; { 275 exitstatus = 0; 276 if (argc >= 2) { /* That's what SVR2 does */ 277 setinputfile(argv[1], 1); 278 commandname = argv[1]; 279 cmdloop(0); 280 popfile(); 281 } 282 return exitstatus; 283 } 284 285 286 exitcmd(argc, argv) char **argv; { 287 if (stoppedjobs()) 288 return; 289 if (argc > 1) 290 exitstatus = number(argv[1]); 291 exitshell(exitstatus); 292 } 293 294 295 #ifdef notdef 296 /* 297 * Should never be called. 298 */ 299 300 void 301 exit(exitstatus) { 302 _exit(exitstatus); 303 } 304 #endif 305
Indexes created Mon Sep 22 13:09:51 GMT 2025