main.c revision 1.43 1 /* $NetBSD: main.c,v 1.43 2002/09/27 22:56:24 christos Exp $ */
2
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. All advertising materials mentioning features or use of this software
19 * must display the following acknowledgement:
20 * This product includes software developed by the University of
21 * California, Berkeley and its contributors.
22 * 4. Neither the name of the University nor the names of its contributors
23 * may be used to endorse or promote products derived from this software
24 * without specific prior written permission.
25 *
26 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
27 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
28 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
29 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
30 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
31 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
32 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
33 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
34 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
35 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
36 * SUCH DAMAGE.
37 */
38
39 #include <sys/cdefs.h>
40 #ifndef lint
41 __COPYRIGHT("@(#) Copyright (c) 1991, 1993\n\
42 The Regents of the University of California. All rights reserved.\n");
43 #endif /* not lint */
44
45 #ifndef lint
46 #if 0
47 static char sccsid[] = "@(#)main.c 8.7 (Berkeley) 7/19/95";
48 #else
49 __RCSID("$NetBSD: main.c,v 1.43 2002/09/27 22:56:24 christos Exp $");
50 #endif
51 #endif /* not lint */
52
53 #include <errno.h>
54 #include <stdio.h>
55 #include <signal.h>
56 #include <sys/stat.h>
57 #include <unistd.h>
58 #include <fcntl.h>
59
60
61 #include "shell.h"
62 #include "main.h"
63 #include "mail.h"
64 #include "options.h"
65 #include "output.h"
66 #include "parser.h"
67 #include "nodes.h"
68 #include "expand.h"
69 #include "eval.h"
70 #include "jobs.h"
71 #include "input.h"
72 #include "trap.h"
73 #include "var.h"
74 #include "show.h"
75 #include "memalloc.h"
76 #include "error.h"
77 #include "init.h"
78 #include "mystring.h"
79 #include "exec.h"
80 #include "cd.h"
81
82 #define PROFILE 0
83
84 int rootpid;
85 int rootshell;
86 STATIC union node *curcmd;
87 STATIC union node *prevcmd;
88 #if PROFILE
89 short profile_buf[16384];
90 extern int etext();
91 #endif
92
93 STATIC void read_profile __P((const char *));
94 STATIC char *find_dot_file __P((char *));
95 int main __P((int, char **));
96
97 extern int oexitstatus;
98 /*
99 * Main routine. We initialize things, parse the arguments, execute
100 * profiles if we're a login shell, and then call cmdloop to execute
101 * commands. The setjmp call sets up the location to jump to when an
102 * exception occurs. When an exception occurs the variable "state"
103 * is used to figure out how far we had gotten.
104 */
105
106 int
107 main(argc, argv)
108 int argc;
109 char **argv;
110 {
111 struct jmploc jmploc;
112 struct stackmark smark;
113 volatile int state;
114 char *shinit;
115
116 #if PROFILE
117 monitor(4, etext, profile_buf, sizeof profile_buf, 50);
118 #endif
119 state = 0;
120 if (setjmp(jmploc.loc)) {
121 /*
122 * When a shell procedure is executed, we raise the
123 * exception EXSHELLPROC to clean up before executing
124 * the shell procedure.
125 */
126 switch (exception) {
127 case EXSHELLPROC:
128 rootpid = getpid();
129 rootshell = 1;
130 minusc = NULL;
131 state = 3;
132 break;
133
134 case EXEXEC:
135 exitstatus = exerrno;
136 break;
137
138 case EXERROR:
139 exitstatus = 2;
140 break;
141
142 default:
143 break;
144 }
145
146 if (exception != EXSHELLPROC) {
147 if (state == 0 || iflag == 0 || ! rootshell)
148 exitshell(exitstatus);
149 }
150 reset();
151 if (exception == EXINT
152 #if ATTY
153 && (! attyset() || equal(termval(), "emacs"))
154 #endif
155 ) {
156 out2c('\n');
157 flushout(&errout);
158 }
159 popstackmark(&smark);
160 FORCEINTON; /* enable interrupts */
161 if (state == 1)
162 goto state1;
163 else if (state == 2)
164 goto state2;
165 else if (state == 3)
166 goto state3;
167 else
168 goto state4;
169 }
170 handler = &jmploc;
171 #ifdef DEBUG
172 opentrace();
173 trputs("Shell args: "); trargs(argv);
174 #endif
175 rootpid = getpid();
176 rootshell = 1;
177 init();
178 setstackmark(&smark);
179 procargs(argc, argv);
180 if (argv[0] && argv[0][0] == '-') {
181 state = 1;
182 read_profile("/etc/profile");
183 state1:
184 state = 2;
185 read_profile(".profile");
186 }
187 state2:
188 state = 3;
189 if (getuid() == geteuid() && getgid() == getegid()) {
190 if ((shinit = lookupvar("ENV")) != NULL && *shinit != '\0') {
191 state = 3;
192 read_profile(shinit);
193 }
194 }
195 state3:
196 state = 4;
197 if (sflag == 0 || minusc) {
198 static int sigs[] = {
199 SIGINT, SIGQUIT, SIGHUP,
200 #ifdef SIGTSTP
201 SIGTSTP,
202 #endif
203 SIGPIPE
204 };
205 #define SIGSSIZE (sizeof(sigs)/sizeof(sigs[0]))
206 int i;
207
208 for (i = 0; i < SIGSSIZE; i++)
209 setsignal(sigs[i], 0);
210 }
211
212 if (minusc)
213 evalstring(minusc, 0);
214
215 if (sflag || minusc == NULL) {
216 state4: /* XXX ??? - why isn't this before the "if" statement */
217 cmdloop(1);
218 }
219 #if PROFILE
220 monitor(0);
221 #endif
222 exitshell(exitstatus);
223 /* NOTREACHED */
224 }
225
226
227 /*
228 * Read and execute commands. "Top" is nonzero for the top level command
229 * loop; it turns on prompting if the shell is interactive.
230 */
231
232 void
233 cmdloop(top)
234 int top;
235 {
236 union node *n;
237 struct stackmark smark;
238 int inter;
239 int numeof = 0;
240 int isroot;
241
242 TRACE(("cmdloop(%d) called\n", top));
243 setstackmark(&smark);
244 for (;;) {
245 if (pendingsigs)
246 dotrap();
247 inter = 0;
248 if (iflag && top) {
249 inter++;
250 showjobs(1);
251 chkmail(0);
252 flushout(&output);
253 }
254 n = parsecmd(inter);
255 /* showtree(n); DEBUG */
256 if (n == NEOF) {
257 if (!top || numeof >= 50)
258 break;
259 if (!stoppedjobs()) {
260 if (!Iflag)
261 break;
262 out2str("\nUse \"exit\" to leave shell.\n");
263 }
264 numeof++;
265 } else if (n != NULL && nflag == 0) {
266 job_warning = (job_warning == 2) ? 1 : 0;
267 numeof = 0;
268 isroot = rootshell;
269 evaltree(n, 0, &isroot);
270 }
271 popstackmark(&smark);
272 setstackmark(&smark);
273 if (evalskip == SKIPFILE) {
274 evalskip = 0;
275 break;
276 }
277 }
278 popstackmark(&smark);
279 }
280
281
282
283 /*
284 * Read /etc/profile or .profile. Return on error.
285 */
286
287 STATIC void
288 read_profile(name)
289 const char *name;
290 {
291 int fd;
292 int xflag_set = 0;
293 int vflag_set = 0;
294
295 INTOFF;
296 if ((fd = open(name, O_RDONLY)) >= 0)
297 setinputfd(fd, 1);
298 INTON;
299 if (fd < 0)
300 return;
301 /* -q turns off -x and -v just when executing init files */
302 if (qflag) {
303 if (xflag)
304 xflag = 0, xflag_set = 1;
305 if (vflag)
306 vflag = 0, vflag_set = 1;
307 }
308 cmdloop(0);
309 if (qflag) {
310 if (xflag_set)
311 xflag = 1;
312 if (vflag_set)
313 vflag = 1;
314 }
315 popfile();
316 }
317
318
319
320 /*
321 * Read a file containing shell functions.
322 */
323
324 void
325 readcmdfile(name)
326 char *name;
327 {
328 int fd;
329
330 INTOFF;
331 if ((fd = open(name, O_RDONLY)) >= 0)
332 setinputfd(fd, 1);
333 else
334 error("Can't open %s", name);
335 INTON;
336 cmdloop(0);
337 popfile();
338 }
339
340
341
342 /*
343 * Take commands from a file. To be compatible we should do a path
344 * search for the file, which is necessary to find sub-commands.
345 */
346
347
348 STATIC char *
349 find_dot_file(basename)
350 char *basename;
351 {
352 char *fullname;
353 const char *path = pathval();
354 struct stat statb;
355
356 /* don't try this for absolute or relative paths */
357 if (strchr(basename, '/'))
358 return basename;
359
360 while ((fullname = padvance(&path, basename)) != NULL) {
361 if ((stat(fullname, &statb) == 0) && S_ISREG(statb.st_mode)) {
362 /*
363 * Don't bother freeing here, since it will
364 * be freed by the caller.
365 */
366 return fullname;
367 }
368 stunalloc(fullname);
369 }
370
371 /* not found in the PATH */
372 error("%s: not found", basename);
373 /* NOTREACHED */
374 }
375
376 int
377 dotcmd(argc, argv)
378 int argc;
379 char **argv;
380 {
381 struct strlist *sp;
382 exitstatus = 0;
383
384 for (sp = cmdenviron; sp ; sp = sp->next)
385 setvareq(savestr(sp->text), VSTRFIXED|VTEXTFIXED);
386
387 if (argc >= 2) { /* That's what SVR2 does */
388 char *fullname;
389 struct stackmark smark;
390
391 setstackmark(&smark);
392 fullname = find_dot_file(argv[1]);
393 setinputfile(fullname, 1);
394 commandname = fullname;
395 cmdloop(0);
396 popfile();
397 popstackmark(&smark);
398 }
399 return exitstatus;
400 }
401
402
403 int
404 exitcmd(argc, argv)
405 int argc;
406 char **argv;
407 {
408 if (stoppedjobs())
409 return 0;
410 if (argc > 1)
411 exitstatus = number(argv[1]);
412 else
413 exitstatus = oexitstatus;
414 exitshell(exitstatus);
415 /* NOTREACHED */
416 }
417