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
main(int argc,char * argv[])99 main(int argc, char *argv[])
100 {
101 struct stackmark smark, smark2;
102 volatile int state;
103 char *shinit;
104 int login;
105
106 (void) setlocale(LC_ALL, "");
107 initcharset();
108 state = 0;
109 if (setjmp(main_handler.loc)) {
110 if (state == 0 || iflag == 0 || ! rootshell ||
111 exception == EXEXIT)
112 exitshell(exitstatus);
113 reset();
114 if (exception == EXINT)
115 out2fmt_flush("\n");
116 popstackmark(&smark);
117 FORCEINTON; /* enable interrupts */
118 if (state == 1)
119 goto state1;
120 else if (state == 2)
121 goto state2;
122 else if (state == 3)
123 goto state3;
124 else
125 goto state4;
126 }
127 handler = &main_handler;
128 #ifdef DEBUG
129 opentrace();
130 trputs("Shell args: "); trargs(argv);
131 #endif
132 rootpid = getpid();
133 rootshell = 1;
134 INTOFF;
135 initvar();
136 setstackmark(&smark);
137 setstackmark(&smark2);
138 login = procargs(argc, argv);
139 trap_init();
140 pwd_init(iflag);
141 INTON;
142 if (iflag)
143 chkmail(1);
144 if (login) {
145 state = 1;
146 read_profile("/etc/profile");
147 state1:
148 state = 2;
149 if (privileged == 0)
150 read_profile("${HOME-}/.profile");
151 else
152 read_profile("/etc/suid_profile");
153 }
154 state2:
155 state = 3;
156 if (!privileged && iflag) {
157 if ((shinit = lookupvar("ENV")) != NULL && *shinit != '\0') {
158 state = 3;
159 read_profile(shinit);
160 }
161 }
162 #ifndef NO_HISTORY
163 if (iflag)
164 histload();
165 #endif
166 state3:
167 state = 4;
168 popstackmark(&smark2);
169 if (minusc) {
170 evalstring(minusc, sflag ? 0 : EV_EXIT);
171 }
172 state4:
173 if (sflag || minusc == NULL) {
174 cmdloop(1);
175 }
176 exitshell(exitstatus);
177 /*NOTREACHED*/
178 return 0;
179 }
180
181 static void
reset(void)182 reset(void)
183 {
184 reseteval();
185 resetinput();
186 }
187
188 /*
189 * Read and execute commands. "Top" is nonzero for the top level command
190 * loop; it turns on prompting if the shell is interactive.
191 */
192
193 static void
cmdloop(int top)194 cmdloop(int top)
195 {
196 union node *n;
197 struct stackmark smark;
198 int inter;
199 int numeof = 0;
200
201 TRACE(("cmdloop(%d) called\n", top));
202 setstackmark(&smark);
203 for (;;) {
204 if (pendingsig)
205 dotrap();
206 inter = 0;
207 if (iflag && top) {
208 inter++;
209 showjobs(1, SHOWJOBS_DEFAULT);
210 chkmail(0);
211 flushout(&output);
212 }
213 n = parsecmd(inter);
214 /* showtree(n); DEBUG */
215 if (n == NEOF) {
216 if (!top || numeof >= 50)
217 break;
218 if (!stoppedjobs()) {
219 if (!Iflag)
220 break;
221 out2fmt_flush("\nUse \"exit\" to leave shell.\n");
222 }
223 numeof++;
224 } else if (n != NULL && nflag == 0) {
225 job_warning = (job_warning == 2) ? 1 : 0;
226 numeof = 0;
227 evaltree(n, 0);
228 }
229 popstackmark(&smark);
230 setstackmark(&smark);
231 if (evalskip != 0) {
232 if (evalskip == SKIPRETURN)
233 evalskip = 0;
234 break;
235 }
236 }
237 popstackmark(&smark);
238 if (top && iflag) {
239 out2c('\n');
240 flushout(out2);
241 }
242 }
243
244
245
246 /*
247 * Read /etc/profile or .profile. Return on error.
248 */
249
250 static void
read_profile(const char * name)251 read_profile(const char *name)
252 {
253 int fd;
254 const char *expandedname;
255
256 expandedname = expandstr(name);
257 if (expandedname == NULL)
258 return;
259 INTOFF;
260 if ((fd = open(expandedname, O_RDONLY | O_CLOEXEC)) >= 0)
261 setinputfd(fd, 1);
262 INTON;
263 if (fd < 0)
264 return;
265 cmdloop(0);
266 popfile();
267 }
268
269
270
271 /*
272 * Read a file containing shell functions.
273 */
274
275 void
readcmdfile(const char * name)276 readcmdfile(const char *name)
277 {
278 setinputfile(name, 1);
279 cmdloop(0);
280 popfile();
281 }
282
283
284
285 /*
286 * Take commands from a file. To be compatible we should do a path
287 * search for the file, which is necessary to find sub-commands.
288 */
289
290
291 static char *
find_dot_file(char * basename)292 find_dot_file(char *basename)
293 {
294 char *fullname;
295 const char *opt;
296 const char *path = pathval();
297 struct stat statb;
298
299 /* don't try this for absolute or relative paths */
300 if( strchr(basename, '/'))
301 return basename;
302
303 while ((fullname = padvance(&path, &opt, basename)) != NULL) {
304 if ((stat(fullname, &statb) == 0) && S_ISREG(statb.st_mode)) {
305 /*
306 * Don't bother freeing here, since it will
307 * be freed by the caller.
308 */
309 return fullname;
310 }
311 stunalloc(fullname);
312 }
313 return basename;
314 }
315
316 int
dotcmd(int argc,char ** argv)317 dotcmd(int argc, char **argv)
318 {
319 char *filename, *fullname;
320
321 if (argc < 2)
322 error("missing filename");
323
324 exitstatus = 0;
325
326 /*
327 * Because we have historically not supported any options,
328 * only treat "--" specially.
329 */
330 filename = argc > 2 && strcmp(argv[1], "--") == 0 ? argv[2] : argv[1];
331
332 fullname = find_dot_file(filename);
333 setinputfile(fullname, 1);
334 commandname = fullname;
335 cmdloop(0);
336 popfile();
337 return exitstatus;
338 }
339
340
341 int
exitcmd(int argc,char ** argv)342 exitcmd(int argc, char **argv)
343 {
344 if (stoppedjobs())
345 return 0;
346 if (argc > 1)
347 exitshell(number(argv[1]));
348 else
349 exitshell_savedstatus();
350 }
351