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