xref: /netbsd-src/usr.bin/ftp/util.c (revision 95d875fb90b1458e4f1de6950286ddcd6644bc61)
1 /*	$NetBSD: util.c,v 1.86 1999/12/03 06:10:01 itojun Exp $	*/
2 
3 /*-
4  * Copyright (c) 1997-1999 The NetBSD Foundation, Inc.
5  * All rights reserved.
6  *
7  * This code is derived from software contributed to The NetBSD Foundation
8  * by Luke Mewburn.
9  *
10  * This code is derived from software contributed to The NetBSD Foundation
11  * by Jason R. Thorpe of the Numerical Aerospace Simulation Facility,
12  * NASA Ames Research Center.
13  *
14  * Redistribution and use in source and binary forms, with or without
15  * modification, are permitted provided that the following conditions
16  * are met:
17  * 1. Redistributions of source code must retain the above copyright
18  *    notice, this list of conditions and the following disclaimer.
19  * 2. Redistributions in binary form must reproduce the above copyright
20  *    notice, this list of conditions and the following disclaimer in the
21  *    documentation and/or other materials provided with the distribution.
22  * 3. All advertising materials mentioning features or use of this software
23  *    must display the following acknowledgement:
24  *	This product includes software developed by the NetBSD
25  *	Foundation, Inc. and its contributors.
26  * 4. Neither the name of The NetBSD Foundation nor the names of its
27  *    contributors may be used to endorse or promote products derived
28  *    from this software without specific prior written permission.
29  *
30  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
31  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
32  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
33  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
34  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
35  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
36  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
37  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
38  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
39  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
40  * POSSIBILITY OF SUCH DAMAGE.
41  */
42 
43 /*
44  * Copyright (c) 1985, 1989, 1993, 1994
45  *	The Regents of the University of California.  All rights reserved.
46  *
47  * Redistribution and use in source and binary forms, with or without
48  * modification, are permitted provided that the following conditions
49  * are met:
50  * 1. Redistributions of source code must retain the above copyright
51  *    notice, this list of conditions and the following disclaimer.
52  * 2. Redistributions in binary form must reproduce the above copyright
53  *    notice, this list of conditions and the following disclaimer in the
54  *    documentation and/or other materials provided with the distribution.
55  * 3. All advertising materials mentioning features or use of this software
56  *    must display the following acknowledgement:
57  *	This product includes software developed by the University of
58  *	California, Berkeley and its contributors.
59  * 4. Neither the name of the University nor the names of its contributors
60  *    may be used to endorse or promote products derived from this software
61  *    without specific prior written permission.
62  *
63  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
64  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
65  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
66  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
67  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
68  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
69  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
70  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
71  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
72  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
73  * SUCH DAMAGE.
74  */
75 
76 #include <sys/cdefs.h>
77 #ifndef lint
78 __RCSID("$NetBSD: util.c,v 1.86 1999/12/03 06:10:01 itojun Exp $");
79 #endif /* not lint */
80 
81 /*
82  * FTP User Program -- Misc support routines
83  */
84 #include <sys/types.h>
85 #include <sys/socket.h>
86 #include <sys/ioctl.h>
87 #include <sys/time.h>
88 #include <netinet/in.h>
89 #include <arpa/ftp.h>
90 
91 #include <ctype.h>
92 #include <err.h>
93 #include <errno.h>
94 #include <fcntl.h>
95 #include <glob.h>
96 #include <signal.h>
97 #include <limits.h>
98 #include <pwd.h>
99 #include <stdio.h>
100 #include <stdlib.h>
101 #include <string.h>
102 #include <termios.h>
103 #include <time.h>
104 #include <tzfile.h>
105 #include <unistd.h>
106 
107 #include "ftp_var.h"
108 
109 /*
110  * Connect to peer server and
111  * auto-login, if possible.
112  */
113 void
114 setpeer(argc, argv)
115 	int argc;
116 	char *argv[];
117 {
118 	char *host;
119 	char *port;
120 
121 	if (argc == 0)
122 		goto usage;
123 	if (connected) {
124 		fprintf(ttyout, "Already connected to %s, use close first.\n",
125 		    hostname);
126 		code = -1;
127 		return;
128 	}
129 	if (argc < 2)
130 		(void)another(&argc, &argv, "to");
131 	if (argc < 2 || argc > 3) {
132  usage:
133 		fprintf(ttyout, "usage: %s host-name [port]\n", argv[0]);
134 		code = -1;
135 		return;
136 	}
137 	if (gatemode)
138 		port = gateport;
139 	else
140 		port = ftpport;
141 	if (argc > 2)
142 		port = argv[2];
143 
144 	if (gatemode) {
145 		if (gateserver == NULL || *gateserver == '\0')
146 			errx(1, "gateserver not defined (shouldn't happen)");
147 		host = hookup(gateserver, port);
148 	} else
149 		host = hookup(argv[1], port);
150 
151 	if (host) {
152 		int overbose;
153 
154 		if (gatemode && verbose) {
155 			fprintf(ttyout,
156 			    "Connecting via pass-through server %s\n",
157 			    gateserver);
158 		}
159 
160 		connected = 1;
161 		/*
162 		 * Set up defaults for FTP.
163 		 */
164 		(void)strlcpy(typename, "ascii", sizeof(typename));
165 		type = TYPE_A;
166 		curtype = TYPE_A;
167 		(void)strlcpy(formname, "non-print", sizeof(formname));
168 		form = FORM_N;
169 		(void)strlcpy(modename, "stream", sizeof(modename));
170 		mode = MODE_S;
171 		(void)strlcpy(structname, "file", sizeof(structname));
172 		stru = STRU_F;
173 		(void)strlcpy(bytename, "8", sizeof(bytename));
174 		bytesize = 8;
175 		if (autologin)
176 			(void)ftp_login(argv[1], NULL, NULL);
177 
178 		overbose = verbose;
179 		if (debug == 0)
180 			verbose = -1;
181 		if (command("SYST") == COMPLETE && overbose) {
182 			char *cp, c;
183 			c = 0;
184 			cp = strchr(reply_string + 4, ' ');
185 			if (cp == NULL)
186 				cp = strchr(reply_string + 4, '\r');
187 			if (cp) {
188 				if (cp[-1] == '.')
189 					cp--;
190 				c = *cp;
191 				*cp = '\0';
192 			}
193 
194 			fprintf(ttyout, "Remote system type is %s.\n",
195 			    reply_string + 4);
196 			if (cp)
197 				*cp = c;
198 		}
199 		if (!strncmp(reply_string, "215 UNIX Type: L8", 17)) {
200 			if (proxy)
201 				unix_proxy = 1;
202 			else
203 				unix_server = 1;
204 			/*
205 			 * Set type to 0 (not specified by user),
206 			 * meaning binary by default, but don't bother
207 			 * telling server.  We can use binary
208 			 * for text files unless changed by the user.
209 			 */
210 			type = 0;
211 			(void)strlcpy(typename, "binary", sizeof(typename));
212 			if (overbose)
213 			    fprintf(ttyout,
214 				"Using %s mode to transfer files.\n",
215 				typename);
216 		} else {
217 			if (proxy)
218 				unix_proxy = 0;
219 			else
220 				unix_server = 0;
221 			if (overbose &&
222 			    !strncmp(reply_string, "215 TOPS20", 10))
223 				fputs(
224 "Remember to set tenex mode when transferring binary files from this machine.\n",
225 				    ttyout);
226 		}
227 		verbose = overbose;
228 	}
229 }
230 
231 /*
232  * Reset the various variables that indicate connection state back to
233  * disconnected settings.
234  * The caller is responsible for issuing any commands to the remote server
235  * to perform a clean shutdown before this is invoked.
236  */
237 void
238 cleanuppeer()
239 {
240 
241 	if (cout)
242 		(void)fclose(cout);
243 	cout = NULL;
244 	connected = 0;
245 			/*
246 			 * determine if anonftp was specifically set with -a
247 			 * (1), or implicitly set by auto_fetch() (2). in the
248 			 * latter case, disable after the current xfer
249 			 */
250 	if (anonftp == 2)
251 		anonftp = 0;
252 	data = -1;
253 	epsv4bad = 0;
254 	if (username)
255 		free(username);
256 	username = NULL;
257 	if (!proxy)
258 		macnum = 0;
259 }
260 
261 /*
262  * Top-level signal handler for interrupted commands.
263  */
264 void
265 intr(dummy)
266 	int dummy;
267 {
268 
269 	alarmtimer(0);
270 	if (fromatty)
271 		write(fileno(ttyout), "\n", 1);
272 	siglongjmp(toplevel, 1);
273 }
274 
275 /*
276  * Signal handler for lost connections; cleanup various elements of
277  * the connection state, and call cleanuppeer() to finish it off.
278  */
279 void
280 lostpeer(dummy)
281 	int dummy;
282 {
283 	int oerrno = errno;
284 
285 	alarmtimer(0);
286 	if (connected) {
287 		if (cout != NULL) {
288 			(void)shutdown(fileno(cout), 1+1);
289 			(void)fclose(cout);
290 			cout = NULL;
291 		}
292 		if (data >= 0) {
293 			(void)shutdown(data, 1+1);
294 			(void)close(data);
295 			data = -1;
296 		}
297 		connected = 0;
298 	}
299 	pswitch(1);
300 	if (connected) {
301 		if (cout != NULL) {
302 			(void)shutdown(fileno(cout), 1+1);
303 			(void)fclose(cout);
304 			cout = NULL;
305 		}
306 		connected = 0;
307 	}
308 	proxflag = 0;
309 	pswitch(0);
310 	cleanuppeer();
311 	errno = oerrno;
312 }
313 
314 
315 /*
316  * login to remote host, using given username & password if supplied
317  */
318 int
319 ftp_login(host, user, pass)
320 	const char *host;
321 	const char *user, *pass;
322 {
323 	char tmp[80];
324 	const char *acct;
325 	struct passwd *pw;
326 	int n, aflag, rval, freeuser, freepass, freeacct;
327 
328 	acct = NULL;
329 	aflag = rval = freeuser = freepass = freeacct = 0;
330 
331 	if (debug)
332 		fprintf(ttyout, "ftp_login: user `%s' pass `%s' host `%s'\n",
333 		    user ? user : "<null>", pass ? pass : "<null>",
334 		    host ? host : "<null>");
335 
336 
337 	/*
338 	 * Set up arguments for an anonymous FTP session, if necessary.
339 	 */
340 	if (anonftp) {
341 		user = "anonymous";	/* as per RFC 1635 */
342 		pass = getoptionvalue("anonpass");
343 	}
344 
345 	if (user == NULL)
346 		freeuser = 1;
347 	if (pass == NULL)
348 		freepass = 1;
349 	freeacct = 1;
350 	if (ruserpass(host, &user, &pass, &acct) < 0) {
351 		code = -1;
352 		goto cleanup_ftp_login;
353 	}
354 
355 	while (user == NULL) {
356 		const char *myname = getlogin();
357 
358 		if (myname == NULL && (pw = getpwuid(getuid())) != NULL)
359 			myname = pw->pw_name;
360 		if (myname)
361 			fprintf(ttyout, "Name (%s:%s): ", host, myname);
362 		else
363 			fprintf(ttyout, "Name (%s): ", host);
364 		*tmp = '\0';
365 		if (fgets(tmp, sizeof(tmp) - 1, stdin) == NULL) {
366 			fprintf(ttyout, "\nEOF received; login aborted.\n");
367 			clearerr(stdin);
368 			code = -1;
369 			goto cleanup_ftp_login;
370 		}
371 		tmp[strlen(tmp) - 1] = '\0';
372 		freeuser = 0;
373 		if (*tmp == '\0')
374 			user = myname;
375 		else
376 			user = tmp;
377 	}
378 
379 	if (gatemode) {
380 		char *nuser;
381 		int len;
382 
383 		len = strlen(user) + 1 + strlen(host) + 1;
384 		nuser = xmalloc(len);
385 		(void)strlcpy(nuser, user, len);
386 		(void)strlcat(nuser, "@",  len);
387 		(void)strlcat(nuser, host, len);
388 		freeuser = 1;
389 		user = nuser;
390 	}
391 
392 	n = command("USER %s", user);
393 	if (n == CONTINUE) {
394 		if (pass == NULL) {
395 			freepass = 0;
396 			pass = getpass("Password:");
397 		}
398 		n = command("PASS %s", pass);
399 	}
400 	if (n == CONTINUE) {
401 		aflag++;
402 		if (acct == NULL) {
403 			freeacct = 0;
404 			acct = getpass("Account:");
405 		}
406 		if (acct[0] == '\0') {
407 			warnx("Login failed.");
408 			goto cleanup_ftp_login;
409 		}
410 		n = command("ACCT %s", acct);
411 	}
412 	if ((n != COMPLETE) ||
413 	    (!aflag && acct != NULL && command("ACCT %s", acct) != COMPLETE)) {
414 		warnx("Login failed.");
415 		goto cleanup_ftp_login;
416 	}
417 	rval = 1;
418 	username = xstrdup(user);
419 	if (proxy)
420 		goto cleanup_ftp_login;
421 
422 	connected = -1;
423 	for (n = 0; n < macnum; ++n) {
424 		if (!strcmp("init", macros[n].mac_name)) {
425 			(void)strlcpy(line, "$init", sizeof(line));
426 			makeargv();
427 			domacro(margc, margv);
428 			break;
429 		}
430 	}
431 	updateremotepwd();
432 
433 cleanup_ftp_login:
434 	if (user != NULL && freeuser)
435 		free((char *)user);
436 	if (pass != NULL && freepass)
437 		free((char *)pass);
438 	if (acct != NULL && freeacct)
439 		free((char *)acct);
440 	return (rval);
441 }
442 
443 /*
444  * `another' gets another argument, and stores the new argc and argv.
445  * It reverts to the top level (via intr()) on EOF/error.
446  *
447  * Returns false if no new arguments have been added.
448  */
449 int
450 another(pargc, pargv, prompt)
451 	int *pargc;
452 	char ***pargv;
453 	const char *prompt;
454 {
455 	int len = strlen(line), ret;
456 
457 	if (len >= sizeof(line) - 3) {
458 		fputs("sorry, arguments too long.\n", ttyout);
459 		intr(0);
460 	}
461 	fprintf(ttyout, "(%s) ", prompt);
462 	line[len++] = ' ';
463 	if (fgets(&line[len], sizeof(line) - len, stdin) == NULL) {
464 		clearerr(stdin);
465 		intr(0);
466 	}
467 	len += strlen(&line[len]);
468 	if (len > 0 && line[len - 1] == '\n')
469 		line[len - 1] = '\0';
470 	makeargv();
471 	ret = margc > *pargc;
472 	*pargc = margc;
473 	*pargv = margv;
474 	return (ret);
475 }
476 
477 /*
478  * glob files given in argv[] from the remote server.
479  * if errbuf isn't NULL, store error messages there instead
480  * of writing to the screen.
481  */
482 char *
483 remglob(argv, doswitch, errbuf)
484         char *argv[];
485         int doswitch;
486 	char **errbuf;
487 {
488         char temp[MAXPATHLEN];
489         static char buf[MAXPATHLEN];
490         static FILE *ftemp = NULL;
491         static char **args;
492         int oldverbose, oldhash, fd, len;
493         char *cp, *mode;
494 
495         if (!mflag || !connected) {
496                 if (!doglob)
497                         args = NULL;
498                 else {
499                         if (ftemp) {
500                                 (void)fclose(ftemp);
501                                 ftemp = NULL;
502                         }
503                 }
504                 return (NULL);
505         }
506         if (!doglob) {
507                 if (args == NULL)
508                         args = argv;
509                 if ((cp = *++args) == NULL)
510                         args = NULL;
511                 return (cp);
512         }
513         if (ftemp == NULL) {
514 		len = strlcpy(temp, tmpdir, sizeof(temp));
515 		if (temp[len - 1] != '/')
516 			(void)strlcat(temp, "/", sizeof(temp));
517 		(void)strlcat(temp, TMPFILE, sizeof(temp));
518                 if ((fd = mkstemp(temp)) < 0) {
519                         warn("unable to create temporary file %s", temp);
520                         return (NULL);
521                 }
522                 close(fd);
523                 oldverbose = verbose;
524 		verbose = (errbuf != NULL) ? -1 : 0;
525                 oldhash = hash;
526                 hash = 0;
527                 if (doswitch)
528                         pswitch(!proxy);
529                 for (mode = "w"; *++argv != NULL; mode = "a")
530                         recvrequest("NLST", temp, *argv, mode, 0, 0);
531 		if ((code / 100) != COMPLETE) {
532 			if (errbuf != NULL)
533 				*errbuf = reply_string;
534 		}
535                 if (doswitch)
536                         pswitch(!proxy);
537                 verbose = oldverbose;
538 		hash = oldhash;
539                 ftemp = fopen(temp, "r");
540                 (void)unlink(temp);
541                 if (ftemp == NULL) {
542 			if (errbuf == NULL)
543 				fputs(
544 				    "can't find list of remote files, oops.\n",
545 				    ttyout);
546 			else
547 				*errbuf =
548 				    "can't find list of remote files, oops.";
549                         return (NULL);
550                 }
551         }
552         if (fgets(buf, sizeof(buf), ftemp) == NULL) {
553                 (void)fclose(ftemp);
554 		ftemp = NULL;
555                 return (NULL);
556         }
557         if ((cp = strchr(buf, '\n')) != NULL)
558                 *cp = '\0';
559         return (buf);
560 }
561 
562 /*
563  * Glob a local file name specification with the expectation of a single
564  * return value. Can't control multiple values being expanded from the
565  * expression, we return only the first.
566  * Returns NULL on error, or a pointer to a buffer containing the filename
567  * that's the caller's responsiblity to free(3) when finished with.
568  */
569 char *
570 globulize(pattern)
571 	const char *pattern;
572 {
573 	glob_t gl;
574 	int flags;
575 	char *p;
576 
577 	if (!doglob)
578 		return (xstrdup(pattern));
579 
580 	flags = GLOB_BRACE|GLOB_NOCHECK|GLOB_TILDE;
581 	memset(&gl, 0, sizeof(gl));
582 	if (glob(pattern, flags, NULL, &gl) || gl.gl_pathc == 0) {
583 		warnx("%s: not found", pattern);
584 		globfree(&gl);
585 		return (NULL);
586 	}
587 	p = xstrdup(gl.gl_pathv[0]);
588 	globfree(&gl);
589 	return (p);
590 }
591 
592 /*
593  * determine size of remote file
594  */
595 off_t
596 remotesize(file, noisy)
597 	const char *file;
598 	int noisy;
599 {
600 	int overbose;
601 	off_t size;
602 
603 	overbose = verbose;
604 	size = -1;
605 	if (debug == 0)
606 		verbose = -1;
607 	if (command("SIZE %s", file) == COMPLETE) {
608 		char *cp, *ep;
609 
610 		cp = strchr(reply_string, ' ');
611 		if (cp != NULL) {
612 			cp++;
613 #ifndef NO_QUAD
614 			size = strtoq(cp, &ep, 10);
615 #else
616 			size = strtol(cp, &ep, 10);
617 #endif
618 			if (*ep != '\0' && !isspace((unsigned char)*ep))
619 				size = -1;
620 		}
621 	} else if (noisy && debug == 0) {
622 		fputs(reply_string, ttyout);
623 		putc('\n', ttyout);
624 	}
625 	verbose = overbose;
626 	return (size);
627 }
628 
629 /*
630  * determine last modification time (in GMT) of remote file
631  */
632 time_t
633 remotemodtime(file, noisy)
634 	const char *file;
635 	int noisy;
636 {
637 	int overbose;
638 	time_t rtime;
639 	int ocode;
640 
641 	overbose = verbose;
642 	ocode = code;
643 	rtime = -1;
644 	if (debug == 0)
645 		verbose = -1;
646 	if (command("MDTM %s", file) == COMPLETE) {
647 		struct tm timebuf;
648 		int yy, mo, day, hour, min, sec;
649 		sscanf(reply_string, "%*s %04d%02d%02d%02d%02d%02d", &yy, &mo,
650 			&day, &hour, &min, &sec);
651 		memset(&timebuf, 0, sizeof(timebuf));
652 		timebuf.tm_sec = sec;
653 		timebuf.tm_min = min;
654 		timebuf.tm_hour = hour;
655 		timebuf.tm_mday = day;
656 		timebuf.tm_mon = mo - 1;
657 		timebuf.tm_year = yy - TM_YEAR_BASE;
658 		timebuf.tm_isdst = -1;
659 		rtime = timegm(&timebuf);
660 		if (rtime == -1 && (noisy || debug != 0))
661 			fprintf(ttyout, "Can't convert %s to a time.\n",
662 			    reply_string);
663 	} else if (noisy && debug == 0) {
664 		fputs(reply_string, ttyout);
665 		putc('\n', ttyout);
666 	}
667 	verbose = overbose;
668 	if (rtime == -1)
669 		code = ocode;
670 	return (rtime);
671 }
672 
673 /*
674  * update global `remotepwd', which contains the state of the remote cwd
675  */
676 void
677 updateremotepwd()
678 {
679 	int	 overbose, ocode, i;
680 	char	*cp;
681 
682 	overbose = verbose;
683 	ocode = code;
684 	if (debug == 0)
685 		verbose = -1;
686 	if (command("PWD") != COMPLETE)
687 		goto badremotepwd;
688 	cp = strchr(reply_string, ' ');
689 	if (cp == NULL || cp[0] == '\0' || cp[1] != '"')
690 		goto badremotepwd;
691 	cp += 2;
692 	for (i = 0; *cp && i < sizeof(remotepwd) - 1; i++, cp++) {
693 		if (cp[0] == '"') {
694 			if (cp[1] == '"')
695 				cp++;
696 			else
697 				break;
698 		}
699 		remotepwd[i] = *cp;
700 	}
701 	remotepwd[i] = '\0';
702 	if (debug)
703 		fprintf(ttyout, "got remotepwd as `%s'\n", remotepwd);
704 	goto cleanupremotepwd;
705  badremotepwd:
706 	remotepwd[0]='\0';
707  cleanupremotepwd:
708 	verbose = overbose;
709 	code = ocode;
710 }
711 
712 #ifndef	NO_PROGRESS
713 
714 /*
715  * return non-zero if we're the current foreground process
716  */
717 int
718 foregroundproc()
719 {
720 	static pid_t pgrp = -1;
721 
722 	if (pgrp == -1)
723 		pgrp = getpgrp();
724 
725 	return (tcgetpgrp(fileno(ttyout)) == pgrp);
726 }
727 
728 
729 static void updateprogressmeter __P((int));
730 
731 /*
732  * SIGALRM handler to update the progress meter
733  */
734 static void
735 updateprogressmeter(dummy)
736 	int dummy;
737 {
738 	int oerrno = errno;
739 
740 	progressmeter(0);
741 	errno = oerrno;
742 }
743 #endif	/* NO_PROGRESS */
744 
745 
746 /*
747  * List of order of magnitude prefixes.
748  * The last is `P', as 2^64 = 16384 Petabytes
749  */
750 static const char prefixes[] = " KMGTP";
751 
752 /*
753  * Display a transfer progress bar if progress is non-zero.
754  * SIGALRM is hijacked for use by this function.
755  * - Before the transfer, set filesize to size of file (or -1 if unknown),
756  *   and call with flag = -1. This starts the once per second timer,
757  *   and a call to updateprogressmeter() upon SIGALRM.
758  * - During the transfer, updateprogressmeter will call progressmeter
759  *   with flag = 0
760  * - After the transfer, call with flag = 1
761  */
762 static struct timeval start;
763 static struct timeval lastupdate;
764 
765 #define	BUFLEFT	(sizeof(buf) - len)
766 
767 void
768 progressmeter(flag)
769 	int flag;
770 {
771 	static off_t lastsize;
772 #ifndef NO_PROGRESS
773 	struct timeval now, td, wait;
774 	off_t cursize, abbrevsize, bytespersec;
775 	double elapsed;
776 	int ratio, barlength, i, len, remaining;
777 
778 			/*
779 			 * Work variables for progress bar.
780 			 *
781 			 * XXX:	if the format of the progress bar changes
782 			 *	(especially the number of characters in the
783 			 *	`static' portion of it), be sure to update
784 			 *	these appropriately.
785 			 */
786 	char		buf[256];	/* workspace for progress bar */
787 #define	BAROVERHEAD	43		/* non `*' portion of progress bar */
788 					/*
789 					 * stars should contain at least
790 					 * sizeof(buf) - BAROVERHEAD entries
791 					 */
792 	const char	stars[] =
793 "*****************************************************************************"
794 "*****************************************************************************"
795 "*****************************************************************************";
796 
797 #endif
798 
799 	if (flag == -1) {
800 		(void)gettimeofday(&start, NULL);
801 		lastupdate = start;
802 		lastsize = restart_point;
803 	}
804 #ifndef NO_PROGRESS
805 	len = 0;
806 	if (!progress || filesize <= 0)
807 		return;
808 
809 	(void)gettimeofday(&now, NULL);
810 	cursize = bytes + restart_point;
811 	timersub(&now, &lastupdate, &wait);
812 	if (cursize > lastsize) {
813 		lastupdate = now;
814 		lastsize = cursize;
815 		wait.tv_sec = 0;
816 	}
817 
818 	/*
819 	 * print progress bar only if we are foreground process.
820 	 */
821 	if (! foregroundproc())
822 		return;
823 
824 	ratio = (int)((double)cursize * 100.0 / (double)filesize);
825 	ratio = MAX(ratio, 0);
826 	ratio = MIN(ratio, 100);
827 	len += snprintf(buf + len, BUFLEFT, "\r%3d%% ", ratio);
828 
829 			/*
830 			 * calculate the length of the `*' bar, ensuring that
831 			 * the number of stars won't exceed the buffer size
832 			 */
833 	barlength = MIN(sizeof(buf) - 1, ttywidth) - BAROVERHEAD;
834 	if (barlength > 0) {
835 		i = barlength * ratio / 100;
836 		len += snprintf(buf + len, BUFLEFT,
837 		    "|%.*s%*s|", i, stars, barlength - i, "");
838 	}
839 
840 	abbrevsize = cursize;
841 	for (i = 0; abbrevsize >= 100000 && i < sizeof(prefixes); i++)
842 		abbrevsize >>= 10;
843 	len += snprintf(buf + len, BUFLEFT,
844 #ifndef NO_QUAD
845 	    " %5lld %c%c ", (long long)abbrevsize,
846 #else
847 	    " %5ld %c%c ", (long)abbrevsize,
848 #endif
849 	    prefixes[i],
850 	    i == 0 ? ' ' : 'B');
851 
852 	timersub(&now, &start, &td);
853 	elapsed = td.tv_sec + (td.tv_usec / 1000000.0);
854 
855 	bytespersec = 0;
856 	if (bytes > 0) {
857 		bytespersec = bytes;
858 		if (elapsed > 0.0)
859 			bytespersec /= elapsed;
860 	}
861 	for (i = 1; bytespersec >= 1024000 && i < sizeof(prefixes); i++)
862 		bytespersec >>= 10;
863 	len += snprintf(buf + len, BUFLEFT,
864 #ifndef NO_QUAD
865 	    " %3lld.%02d %cB/s ", (long long)bytespersec / 1024,
866 #else
867 	    " %3ld.%02d %cB/s ", (long)bytespersec / 1024,
868 #endif
869 	    (int)((bytespersec % 1024) * 100 / 1024),
870 	    prefixes[i]);
871 
872 	if (bytes <= 0 || elapsed <= 0.0 || cursize > filesize) {
873 		len += snprintf(buf + len, BUFLEFT, "   --:-- ETA");
874 	} else if (wait.tv_sec >= STALLTIME) {
875 		len += snprintf(buf + len, BUFLEFT, " - stalled -");
876 	} else {
877 		remaining = (int)
878 		    ((filesize - restart_point) / (bytes / elapsed) - elapsed);
879 		if (remaining >= 100 * SECSPERHOUR)
880 			len += snprintf(buf + len, BUFLEFT, "   --:-- ETA");
881 		else {
882 			i = remaining / SECSPERHOUR;
883 			if (i)
884 				len += snprintf(buf + len, BUFLEFT, "%2d:", i);
885 			else
886 				len += snprintf(buf + len, BUFLEFT, "   ");
887 			i = remaining % SECSPERHOUR;
888 			len += snprintf(buf + len, BUFLEFT,
889 			    "%02d:%02d ETA", i / 60, i % 60);
890 		}
891 	}
892 	if (flag == 1)
893 		len += snprintf(buf + len, BUFLEFT, "\n");
894 	(void)write(fileno(ttyout), buf, len);
895 
896 	if (flag == -1) {
897 		(void)xsignal_restart(SIGALRM, updateprogressmeter, 1);
898 		alarmtimer(1);		/* set alarm timer for 1 Hz */
899 	} else if (flag == 1) {
900 		(void)xsignal(SIGALRM, SIG_DFL);
901 		alarmtimer(0);
902 	}
903 #endif	/* !NO_PROGRESS */
904 }
905 
906 /*
907  * Display transfer statistics.
908  * Requires start to be initialised by progressmeter(-1),
909  * direction to be defined by xfer routines, and filesize and bytes
910  * to be updated by xfer routines
911  * If siginfo is nonzero, an ETA is displayed, and the output goes to stderr
912  * instead of ttyout.
913  */
914 void
915 ptransfer(siginfo)
916 	int siginfo;
917 {
918 	struct timeval now, td, wait;
919 	double elapsed;
920 	off_t bytespersec;
921 	int remaining, hh, i, len;
922 
923 	char buf[256];		/* Work variable for transfer status. */
924 
925 	if (!verbose && !progress && !siginfo)
926 		return;
927 
928 	(void)gettimeofday(&now, NULL);
929 	timersub(&now, &start, &td);
930 	elapsed = td.tv_sec + (td.tv_usec / 1000000.0);
931 	bytespersec = 0;
932 	if (bytes > 0) {
933 		bytespersec = bytes;
934 		if (elapsed > 0.0)
935 			bytespersec /= elapsed;
936 	}
937 	len = 0;
938 	len += snprintf(buf + len, BUFLEFT,
939 #ifndef NO_QUAD
940 	    "%lld byte%s %s in ", (long long)bytes,
941 #else
942 	    "%ld byte%s %s in ", (long)bytes,
943 #endif
944 	    bytes == 1 ? "" : "s", direction);
945 	remaining = (int)elapsed;
946 	if (remaining > SECSPERDAY) {
947 		int days;
948 
949 		days = remaining / SECSPERDAY;
950 		remaining %= SECSPERDAY;
951 		len += snprintf(buf + len, BUFLEFT,
952 		    "%d day%s ", days, days == 1 ? "" : "s");
953 	}
954 	hh = remaining / SECSPERHOUR;
955 	remaining %= SECSPERHOUR;
956 	if (hh)
957 		len += snprintf(buf + len, BUFLEFT, "%2d:", hh);
958 	len += snprintf(buf + len, BUFLEFT,
959 	    "%02d:%02d ", remaining / 60, remaining % 60);
960 
961 	for (i = 1; bytespersec >= 1024000 && i < sizeof(prefixes); i++)
962 		bytespersec >>= 10;
963 	len += snprintf(buf + len, BUFLEFT,
964 #ifndef NO_QUAD
965 	    "(%lld.%02d %cB/s)", (long long)bytespersec / 1024,
966 #else
967 	    "(%ld.%02d %cB/s)", (long)bytespersec / 1024,
968 #endif
969 	    (int)((bytespersec % 1024) * 100 / 1024),
970 	    prefixes[i]);
971 
972 	if (siginfo && bytes > 0 && elapsed > 0.0 && filesize >= 0
973 	    && bytes + restart_point <= filesize) {
974 		remaining = (int)((filesize - restart_point) /
975 				  (bytes / elapsed) - elapsed);
976 		hh = remaining / SECSPERHOUR;
977 		remaining %= SECSPERHOUR;
978 		len += snprintf(buf + len, BUFLEFT, "  ETA: ");
979 		if (hh)
980 			len += snprintf(buf + len, BUFLEFT, "%2d:", hh);
981 		len += snprintf(buf + len, BUFLEFT, "%02d:%02d",
982 		    remaining / 60, remaining % 60);
983 		timersub(&now, &lastupdate, &wait);
984 		if (wait.tv_sec >= STALLTIME)
985 			len += snprintf(buf + len, BUFLEFT, "  (stalled)");
986 	}
987 	len += snprintf(buf + len, BUFLEFT, "\n");
988 	(void)write(siginfo ? STDERR_FILENO : fileno(ttyout), buf, len);
989 }
990 
991 /*
992  * SIG{INFO,QUIT} handler to print transfer stats if a transfer is in progress
993  */
994 void
995 psummary(notused)
996 	int notused;
997 {
998 	int oerrno = errno;
999 
1000 	if (bytes > 0) {
1001 		if (fromatty)
1002 			write(fileno(ttyout), "\n", 1);
1003 		ptransfer(1);
1004 	}
1005 	errno = oerrno;
1006 }
1007 
1008 /*
1009  * List words in stringlist, vertically arranged
1010  */
1011 void
1012 list_vertical(sl)
1013 	StringList *sl;
1014 {
1015 	int i, j, w;
1016 	int columns, width, lines, items;
1017 	char *p;
1018 
1019 	width = items = 0;
1020 
1021 	for (i = 0 ; i < sl->sl_cur ; i++) {
1022 		w = strlen(sl->sl_str[i]);
1023 		if (w > width)
1024 			width = w;
1025 	}
1026 	width = (width + 8) &~ 7;
1027 
1028 	columns = ttywidth / width;
1029 	if (columns == 0)
1030 		columns = 1;
1031 	lines = (sl->sl_cur + columns - 1) / columns;
1032 	for (i = 0; i < lines; i++) {
1033 		for (j = 0; j < columns; j++) {
1034 			p = sl->sl_str[j * lines + i];
1035 			if (p)
1036 				fputs(p, ttyout);
1037 			if (j * lines + i + lines >= sl->sl_cur) {
1038 				putc('\n', ttyout);
1039 				break;
1040 			}
1041 			w = strlen(p);
1042 			while (w < width) {
1043 				w = (w + 8) &~ 7;
1044 				(void)putc('\t', ttyout);
1045 			}
1046 		}
1047 	}
1048 }
1049 
1050 /*
1051  * Update the global ttywidth value, using TIOCGWINSZ.
1052  */
1053 void
1054 setttywidth(a)
1055 	int a;
1056 {
1057 	struct winsize winsize;
1058 	int oerrno = errno;
1059 
1060 	if (ioctl(fileno(ttyout), TIOCGWINSZ, &winsize) != -1 &&
1061 	    winsize.ws_col != 0)
1062 		ttywidth = winsize.ws_col;
1063 	else
1064 		ttywidth = 80;
1065 	errno = oerrno;
1066 }
1067 
1068 /*
1069  * Change the rate limit up (SIGUSR1) or down (SIGUSR2)
1070  */
1071 void
1072 crankrate(sig)
1073 	int sig;
1074 {
1075 
1076 	switch (sig) {
1077 	case SIGUSR1:
1078 		if (rate_get)
1079 			rate_get += rate_get_incr;
1080 		if (rate_put)
1081 			rate_put += rate_put_incr;
1082 		break;
1083 	case SIGUSR2:
1084 		if (rate_get && rate_get > rate_get_incr)
1085 			rate_get -= rate_get_incr;
1086 		if (rate_put && rate_put > rate_put_incr)
1087 			rate_put -= rate_put_incr;
1088 		break;
1089 	default:
1090 		err(1, "crankrate invoked with unknown signal: %d", sig);
1091 	}
1092 }
1093 
1094 
1095 /*
1096  * Set the SIGALRM interval timer for wait seconds, 0 to disable.
1097  */
1098 void
1099 alarmtimer(wait)
1100 	int wait;
1101 {
1102 	struct itimerval itv;
1103 
1104 	itv.it_value.tv_sec = wait;
1105 	itv.it_value.tv_usec = 0;
1106 	itv.it_interval = itv.it_value;
1107 	setitimer(ITIMER_REAL, &itv, NULL);
1108 }
1109 
1110 /*
1111  * Setup or cleanup EditLine structures
1112  */
1113 #ifndef NO_EDITCOMPLETE
1114 void
1115 controlediting()
1116 {
1117 	if (editing && el == NULL && hist == NULL) {
1118 		HistEvent ev;
1119 		int editmode;
1120 
1121 		el = el_init(__progname, stdin, ttyout, stderr);
1122 		/* init editline */
1123 		hist = history_init();		/* init the builtin history */
1124 		history(hist, &ev, H_SETSIZE, 100);/* remember 100 events */
1125 		el_set(el, EL_HIST, history, hist);	/* use history */
1126 
1127 		el_set(el, EL_EDITOR, "emacs");	/* default editor is emacs */
1128 		el_set(el, EL_PROMPT, prompt);	/* set the prompt functions */
1129 		el_set(el, EL_RPROMPT, rprompt);
1130 
1131 		/* add local file completion, bind to TAB */
1132 		el_set(el, EL_ADDFN, "ftp-complete",
1133 		    "Context sensitive argument completion",
1134 		    complete);
1135 		el_set(el, EL_BIND, "^I", "ftp-complete", NULL);
1136 		el_source(el, NULL);	/* read ~/.editrc */
1137 		if ((el_get(el, EL_EDITMODE, &editmode) != -1) && editmode == 0)
1138 			editing = 0;	/* the user doesn't want editing,
1139 					 * so disable, and let statement
1140 					 * below cleanup */
1141 		else
1142 			el_set(el, EL_SIGNAL, 1);
1143 	}
1144 	if (!editing) {
1145 		if (hist) {
1146 			history_end(hist);
1147 			hist = NULL;
1148 		}
1149 		if (el) {
1150 			el_end(el);
1151 			el = NULL;
1152 		}
1153 	}
1154 }
1155 #endif /* !NO_EDITCOMPLETE */
1156 
1157 /*
1158  * Convert the string `arg' to an int, which may have an optional SI suffix
1159  * (`b', `k', `m', `g'). Returns the number for success, -1 otherwise.
1160  */
1161 int
1162 strsuftoi(arg)
1163 	const char *arg;
1164 {
1165 	char *cp;
1166 	long val;
1167 
1168 	if (!isdigit((unsigned char)arg[0]))
1169 		return (-1);
1170 
1171 	val = strtol(arg, &cp, 10);
1172 	if (cp != NULL) {
1173 		if (cp[0] != '\0' && cp[1] != '\0')
1174 			 return (-1);
1175 		switch (tolower((unsigned char)cp[0])) {
1176 		case '\0':
1177 		case 'b':
1178 			break;
1179 		case 'k':
1180 			val <<= 10;
1181 			break;
1182 		case 'm':
1183 			val <<= 20;
1184 			break;
1185 		case 'g':
1186 			val <<= 30;
1187 			break;
1188 		default:
1189 			return (-1);
1190 		}
1191 	}
1192 	if (val < 0 || val > INT_MAX)
1193 		return (-1);
1194 
1195 	return (val);
1196 }
1197 
1198 /*
1199  * Set up socket buffer sizes before a connection is made.
1200  */
1201 void
1202 setupsockbufsize(sock)
1203 	int sock;
1204 {
1205 
1206 	if (setsockopt(sock, SOL_SOCKET, SO_SNDBUF, (void *) &sndbuf_size,
1207 	    sizeof(rcvbuf_size)) < 0)
1208 		warn("unable to set sndbuf size %d", sndbuf_size);
1209 
1210 	if (setsockopt(sock, SOL_SOCKET, SO_RCVBUF, (void *) &rcvbuf_size,
1211 	    sizeof(rcvbuf_size)) < 0)
1212 		warn("unable to set rcvbuf size %d", rcvbuf_size);
1213 }
1214 
1215 /*
1216  * Copy characters from src into dst, \ quoting characters that require it
1217  */
1218 void
1219 ftpvis(dst, dstlen, src, srclen)
1220 	char		*dst;
1221 	size_t		 dstlen;
1222 	const char	*src;
1223 	size_t		 srclen;
1224 {
1225 	int	di, si;
1226 
1227 	for (di = si = 0;
1228 	    src[si] != '\0' && di < dstlen && si < srclen;
1229 	    di++, si++) {
1230 		switch (src[si]) {
1231 		case '\\':
1232 		case ' ':
1233 		case '\t':
1234 		case '\r':
1235 		case '\n':
1236 		case '"':
1237 			dst[di++] = '\\';
1238 			if (di >= dstlen)
1239 				break;
1240 			/* FALLTHROUGH */
1241 		default:
1242 			dst[di] = src[si];
1243 		}
1244 	}
1245 	dst[di] = '\0';
1246 }
1247 
1248 /*
1249  * Copy src into buf (which is len bytes long), expanding % sequences.
1250  */
1251 void
1252 formatbuf(buf, len, src)
1253 	char		*buf;
1254 	size_t		 len;
1255 	const char	*src;
1256 {
1257 	const char	*p;
1258 	char		*p2, *q;
1259 	int		 i, op, updirs, pdirs;
1260 
1261 #define ADDBUF(x) do { \
1262 		if (i >= len - 1) \
1263 			goto endbuf; \
1264 		buf[i++] = (x); \
1265 	} while (0)
1266 
1267 	p = src;
1268 	for (i = 0; *p; p++) {
1269 		if (*p != '%') {
1270 			ADDBUF(*p);
1271 			continue;
1272 		}
1273 		p++;
1274 
1275 		switch (op = *p) {
1276 
1277 		case '/':
1278 		case '.':
1279 		case 'c':
1280 			p2 = connected ? remotepwd : "";
1281 			updirs = pdirs = 0;
1282 
1283 			/* option to determine fixed # of dirs from path */
1284 			if (op == '.' || op == 'c') {
1285 				int skip;
1286 
1287 				q = p2;
1288 				while (*p2)		/* calc # of /'s */
1289 					if (*p2++ == '/')
1290 						updirs++;
1291 				if (p[1] == '0') {	/* print <x> or ... */
1292 					pdirs = 1;
1293 					p++;
1294 				}
1295 				if (p[1] >= '1' && p[1] <= '9') {
1296 							/* calc # to skip  */
1297 					skip = p[1] - '0';
1298 					p++;
1299 				} else
1300 					skip = 1;
1301 
1302 				updirs -= skip;
1303 				while (skip-- > 0) {
1304 					while ((p2 > q) && (*p2 != '/'))
1305 						p2--;	/* back up */
1306 					if (skip && p2 > q)
1307 						p2--;
1308 				}
1309 				if (*p2 == '/' && p2 != q)
1310 					p2++;
1311 			}
1312 
1313 			if (updirs > 0 && pdirs) {
1314 				if (i >= len - 5)
1315 					break;
1316 				if (op == '.') {
1317 					ADDBUF('.');
1318 					ADDBUF('.');
1319 					ADDBUF('.');
1320 				} else {
1321 					ADDBUF('/');
1322 					ADDBUF('<');
1323 					if (updirs > 9) {
1324 						ADDBUF('9');
1325 						ADDBUF('+');
1326 					} else
1327 						ADDBUF('0' + updirs);
1328 					ADDBUF('>');
1329 				}
1330 			}
1331 			for (; *p2; p2++)
1332 				ADDBUF(*p2);
1333 			break;
1334 
1335 		case 'M':
1336 		case 'm':
1337 			for (p2 = connected ? hostname : "-"; *p2; p2++) {
1338 				if (op == 'm' && *p2 == '.')
1339 					break;
1340 				ADDBUF(*p2);
1341 			}
1342 			break;
1343 
1344 		case 'n':
1345 			for (p2 = connected ? username : "-"; *p2 ; p2++)
1346 				ADDBUF(*p2);
1347 			break;
1348 
1349 		case '%':
1350 			ADDBUF('%');
1351 			break;
1352 
1353 		default:		/* display unknown codes literally */
1354 			ADDBUF('%');
1355 			ADDBUF(op);
1356 			break;
1357 
1358 		}
1359 	}
1360  endbuf:
1361 	buf[i] = '\0';
1362 }
1363 
1364 /*
1365  * Determine if given string is an IPv6 address or not.
1366  * Return 1 for yes, 0 for no
1367  */
1368 int
1369 isipv6addr(addr)
1370 	const char *addr;
1371 {
1372 	int rv = 0;
1373 #ifdef INET6
1374 	struct sockaddr_in6 su_sin6;
1375 
1376 	rv = inet_pton(AF_INET6, addr, &su_sin6.sin6_addr);
1377 	if (debug)
1378 		fprintf(ttyout, "isipv6addr: got %d for %s\n", rv, addr);
1379 #endif
1380 	return (rv == 1) ? 1 : 0;
1381 }
1382 
1383 
1384 /*
1385  * Internal version of connect(2); sets socket buffer sizes first.
1386  */
1387 int
1388 xconnect(sock, name, namelen)
1389 	int sock;
1390 	const struct sockaddr *name;
1391 	int namelen;
1392 {
1393 
1394 	setupsockbufsize(sock);
1395 	return (connect(sock, name, namelen));
1396 }
1397 
1398 /*
1399  * Internal version of listen(2); sets socket buffer sizes first.
1400  */
1401 int
1402 xlisten(sock, backlog)
1403 	int sock, backlog;
1404 {
1405 
1406 	setupsockbufsize(sock);
1407 	return (listen(sock, backlog));
1408 }
1409 
1410 /*
1411  * malloc() with inbuilt error checking
1412  */
1413 void *
1414 xmalloc(size)
1415 	size_t size;
1416 {
1417 	void *p;
1418 
1419 	p = malloc(size);
1420 	if (p == NULL)
1421 		err(1, "Unable to allocate %ld bytes of memory", (long)size);
1422 	return (p);
1423 }
1424 
1425 /*
1426  * sl_init() with inbuilt error checking
1427  */
1428 StringList *
1429 xsl_init()
1430 {
1431 	StringList *p;
1432 
1433 	p = sl_init();
1434 	if (p == NULL)
1435 		err(1, "Unable to allocate memory for stringlist");
1436 	return (p);
1437 }
1438 
1439 /*
1440  * sl_add() with inbuilt error checking
1441  */
1442 void
1443 xsl_add(sl, i)
1444 	StringList	*sl;
1445 	char		*i;
1446 {
1447 
1448 	if (sl_add(sl, i) == -1)
1449 		err(1, "Unable to add `%s' to stringlist", i);
1450 }
1451 
1452 /*
1453  * strdup() with inbuilt error checking
1454  */
1455 char *
1456 xstrdup(str)
1457 	const char *str;
1458 {
1459 	char *s;
1460 
1461 	if (str == NULL)
1462 		errx(1, "xstrdup() called with NULL argument");
1463 	s = strdup(str);
1464 	if (s == NULL)
1465 		err(1, "Unable to allocate memory for string copy");
1466 	return (s);
1467 }
1468 
1469 /*
1470  * Install a POSIX signal handler, allowing the invoker to set whether
1471  * the signal should be restartable or not
1472  */
1473 sig_t
1474 xsignal_restart(sig, func, restartable)
1475 	int sig;
1476 	void (*func) __P((int));
1477 	int restartable;
1478 {
1479 	struct sigaction act, oact;
1480 	act.sa_handler = func;
1481 
1482 	sigemptyset(&act.sa_mask);
1483 #if defined(SA_RESTART)			/* 4.4BSD, Posix(?), SVR4 */
1484 	act.sa_flags = restartable ? SA_RESTART : 0;
1485 #elif defined(SA_INTERRUPT)		/* SunOS 4.x */
1486 	act.sa_flags = restartable ? 0 : SA_INTERRUPT;
1487 #else
1488 #error "system must have SA_RESTART or SA_INTERRUPT"
1489 #endif
1490 	if (sigaction(sig, &act, &oact) < 0)
1491 		return (SIG_ERR);
1492 	return (oact.sa_handler);
1493 }
1494 
1495 /*
1496  * Install a signal handler with the `restartable' flag set dependent upon
1497  * which signal is being set. (This is a wrapper to xsignal_restart())
1498  */
1499 sig_t
1500 xsignal(sig, func)
1501 	int sig;
1502 	void (*func) __P((int));
1503 {
1504 	int restartable;
1505 
1506 	/*
1507 	 * Some signals print output or change the state of the process.
1508 	 * There should be restartable, so that reads and writes are
1509 	 * not affected.  Some signals should cause program flow to change;
1510 	 * these signals should not be restartable, so that the system call
1511 	 * will return with EINTR, and the program will go do something
1512 	 * different.  If the signal handler calls longjmp() or siglongjmp(),
1513 	 * it doesn't matter if it's restartable.
1514 	 */
1515 
1516 	switch(sig) {
1517 #ifdef SIGINFO
1518 	case SIGINFO:
1519 #endif
1520 	case SIGQUIT:
1521 	case SIGUSR1:
1522 	case SIGUSR2:
1523 	case SIGWINCH:
1524 		restartable = 1;
1525 		break;
1526 
1527 	case SIGALRM:
1528 	case SIGINT:
1529 	case SIGPIPE:
1530 		restartable = 0;
1531 		break;
1532 
1533 	default:
1534 		/*
1535 		 * This is unpleasant, but I don't know what would be better.
1536 		 * Right now, this "can't happen"
1537 		 */
1538 		errx(1, "xsignal_restart called with signal %d", sig);
1539 	}
1540 
1541 	return(xsignal_restart(sig, func, restartable));
1542 }
1543