xref: /netbsd-src/usr.bin/ftp/util.c (revision 4472dbe5e3bd91ef2540bada7a7ca7384627ff9b)
1 /*	$NetBSD: util.c,v 1.95 2000/05/01 10:35:19 lukem Exp $	*/
2 
3 /*-
4  * Copyright (c) 1997-2000 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 1.95 2000/05/01 10:35:19 lukem 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 #ifdef INET6
107 #include <netdb.h>
108 #endif
109 
110 #include "ftp_var.h"
111 
112 /*
113  * Connect to peer server and
114  * auto-login, if possible.
115  */
116 void
117 setpeer(int argc, char *argv[])
118 {
119 	char *host;
120 	char *port;
121 
122 	if (argc == 0)
123 		goto usage;
124 	if (connected) {
125 		fprintf(ttyout, "Already connected to %s, use close first.\n",
126 		    hostname);
127 		code = -1;
128 		return;
129 	}
130 	if (argc < 2)
131 		(void)another(&argc, &argv, "to");
132 	if (argc < 2 || argc > 3) {
133  usage:
134 		fprintf(ttyout, "usage: %s host-name [port]\n", argv[0]);
135 		code = -1;
136 		return;
137 	}
138 	if (gatemode)
139 		port = gateport;
140 	else
141 		port = ftpport;
142 	if (argc > 2)
143 		port = argv[2];
144 
145 	if (gatemode) {
146 		if (gateserver == NULL || *gateserver == '\0')
147 			errx(1, "gateserver not defined (shouldn't happen)");
148 		host = hookup(gateserver, port);
149 	} else
150 		host = hookup(argv[1], port);
151 
152 	if (host) {
153 		int overbose;
154 
155 		if (gatemode && verbose) {
156 			fprintf(ttyout,
157 			    "Connecting via pass-through server %s\n",
158 			    gateserver);
159 		}
160 
161 		connected = 1;
162 		/*
163 		 * Set up defaults for FTP.
164 		 */
165 		(void)strlcpy(typename, "ascii", sizeof(typename));
166 		type = TYPE_A;
167 		curtype = TYPE_A;
168 		(void)strlcpy(formname, "non-print", sizeof(formname));
169 		form = FORM_N;
170 		(void)strlcpy(modename, "stream", sizeof(modename));
171 		mode = MODE_S;
172 		(void)strlcpy(structname, "file", sizeof(structname));
173 		stru = STRU_F;
174 		(void)strlcpy(bytename, "8", sizeof(bytename));
175 		bytesize = 8;
176 		if (autologin)
177 			(void)ftp_login(argv[1], NULL, NULL);
178 
179 		overbose = verbose;
180 		if (debug == 0)
181 			verbose = -1;
182 		if (command("SYST") == COMPLETE && overbose) {
183 			char *cp, c;
184 			c = 0;
185 			cp = strchr(reply_string + 4, ' ');
186 			if (cp == NULL)
187 				cp = strchr(reply_string + 4, '\r');
188 			if (cp) {
189 				if (cp[-1] == '.')
190 					cp--;
191 				c = *cp;
192 				*cp = '\0';
193 			}
194 
195 			fprintf(ttyout, "Remote system type is %s.\n",
196 			    reply_string + 4);
197 			if (cp)
198 				*cp = c;
199 		}
200 		if (!strncmp(reply_string, "215 UNIX Type: L8", 17)) {
201 			if (proxy)
202 				unix_proxy = 1;
203 			else
204 				unix_server = 1;
205 			/*
206 			 * Set type to 0 (not specified by user),
207 			 * meaning binary by default, but don't bother
208 			 * telling server.  We can use binary
209 			 * for text files unless changed by the user.
210 			 */
211 			type = 0;
212 			(void)strlcpy(typename, "binary", sizeof(typename));
213 			if (overbose)
214 			    fprintf(ttyout,
215 				"Using %s mode to transfer files.\n",
216 				typename);
217 		} else {
218 			if (proxy)
219 				unix_proxy = 0;
220 			else
221 				unix_server = 0;
222 			if (overbose &&
223 			    !strncmp(reply_string, "215 TOPS20", 10))
224 				fputs(
225 "Remember to set tenex mode when transferring binary files from this machine.\n",
226 				    ttyout);
227 		}
228 		verbose = overbose;
229 	}
230 }
231 
232 /*
233  * Reset the various variables that indicate connection state back to
234  * disconnected settings.
235  * The caller is responsible for issuing any commands to the remote server
236  * to perform a clean shutdown before this is invoked.
237  */
238 void
239 cleanuppeer()
240 {
241 
242 	if (cout)
243 		(void)fclose(cout);
244 	cout = NULL;
245 	connected = 0;
246 			/*
247 			 * determine if anonftp was specifically set with -a
248 			 * (1), or implicitly set by auto_fetch() (2). in the
249 			 * latter case, disable after the current xfer
250 			 */
251 	if (anonftp == 2)
252 		anonftp = 0;
253 	data = -1;
254 	epsv4bad = 0;
255 	if (username)
256 		free(username);
257 	username = NULL;
258 	if (!proxy)
259 		macnum = 0;
260 }
261 
262 /*
263  * Top-level signal handler for interrupted commands.
264  */
265 void
266 intr(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(int dummy)
281 {
282 	int oerrno = errno;
283 
284 	alarmtimer(0);
285 	if (connected) {
286 		if (cout != NULL) {
287 			(void)shutdown(fileno(cout), 1+1);
288 			(void)fclose(cout);
289 			cout = NULL;
290 		}
291 		if (data >= 0) {
292 			(void)shutdown(data, 1+1);
293 			(void)close(data);
294 			data = -1;
295 		}
296 		connected = 0;
297 	}
298 	pswitch(1);
299 	if (connected) {
300 		if (cout != NULL) {
301 			(void)shutdown(fileno(cout), 1+1);
302 			(void)fclose(cout);
303 			cout = NULL;
304 		}
305 		connected = 0;
306 	}
307 	proxflag = 0;
308 	pswitch(0);
309 	cleanuppeer();
310 	errno = oerrno;
311 }
312 
313 
314 /*
315  * login to remote host, using given username & password if supplied
316  */
317 int
318 ftp_login(const char *host, const char *user, const char *pass)
319 {
320 	char tmp[80];
321 	const char *acct;
322 	struct passwd *pw;
323 	int n, aflag, rval, freeuser, freepass, freeacct;
324 
325 	acct = NULL;
326 	aflag = rval = freeuser = freepass = freeacct = 0;
327 
328 	if (debug)
329 		fprintf(ttyout, "ftp_login: user `%s' pass `%s' host `%s'\n",
330 		    user ? user : "<null>", pass ? pass : "<null>",
331 		    host ? host : "<null>");
332 
333 
334 	/*
335 	 * Set up arguments for an anonymous FTP session, if necessary.
336 	 */
337 	if (anonftp) {
338 		user = "anonymous";	/* as per RFC 1635 */
339 		pass = getoptionvalue("anonpass");
340 	}
341 
342 	if (user == NULL)
343 		freeuser = 1;
344 	if (pass == NULL)
345 		freepass = 1;
346 	freeacct = 1;
347 	if (ruserpass(host, &user, &pass, &acct) < 0) {
348 		code = -1;
349 		goto cleanup_ftp_login;
350 	}
351 
352 	while (user == NULL) {
353 		const char *myname = getlogin();
354 
355 		if (myname == NULL && (pw = getpwuid(getuid())) != NULL)
356 			myname = pw->pw_name;
357 		if (myname)
358 			fprintf(ttyout, "Name (%s:%s): ", host, myname);
359 		else
360 			fprintf(ttyout, "Name (%s): ", host);
361 		*tmp = '\0';
362 		if (fgets(tmp, sizeof(tmp) - 1, stdin) == NULL) {
363 			fprintf(ttyout, "\nEOF received; login aborted.\n");
364 			clearerr(stdin);
365 			code = -1;
366 			goto cleanup_ftp_login;
367 		}
368 		tmp[strlen(tmp) - 1] = '\0';
369 		freeuser = 0;
370 		if (*tmp == '\0')
371 			user = myname;
372 		else
373 			user = tmp;
374 	}
375 
376 	if (gatemode) {
377 		char *nuser;
378 		int len;
379 
380 		len = strlen(user) + 1 + strlen(host) + 1;
381 		nuser = xmalloc(len);
382 		(void)strlcpy(nuser, user, len);
383 		(void)strlcat(nuser, "@",  len);
384 		(void)strlcat(nuser, host, len);
385 		freeuser = 1;
386 		user = nuser;
387 	}
388 
389 	n = command("USER %s", user);
390 	if (n == CONTINUE) {
391 		if (pass == NULL) {
392 			freepass = 0;
393 			pass = getpass("Password:");
394 		}
395 		n = command("PASS %s", pass);
396 	}
397 	if (n == CONTINUE) {
398 		aflag++;
399 		if (acct == NULL) {
400 			freeacct = 0;
401 			acct = getpass("Account:");
402 		}
403 		if (acct[0] == '\0') {
404 			warnx("Login failed.");
405 			goto cleanup_ftp_login;
406 		}
407 		n = command("ACCT %s", acct);
408 	}
409 	if ((n != COMPLETE) ||
410 	    (!aflag && acct != NULL && command("ACCT %s", acct) != COMPLETE)) {
411 		warnx("Login failed.");
412 		goto cleanup_ftp_login;
413 	}
414 	rval = 1;
415 	username = xstrdup(user);
416 	if (proxy)
417 		goto cleanup_ftp_login;
418 
419 	connected = -1;
420 	for (n = 0; n < macnum; ++n) {
421 		if (!strcmp("init", macros[n].mac_name)) {
422 			(void)strlcpy(line, "$init", sizeof(line));
423 			makeargv();
424 			domacro(margc, margv);
425 			break;
426 		}
427 	}
428 	updateremotepwd();
429 
430 cleanup_ftp_login:
431 	if (user != NULL && freeuser)
432 		free((char *)user);
433 	if (pass != NULL && freepass)
434 		free((char *)pass);
435 	if (acct != NULL && freeacct)
436 		free((char *)acct);
437 	return (rval);
438 }
439 
440 /*
441  * `another' gets another argument, and stores the new argc and argv.
442  * It reverts to the top level (via intr()) on EOF/error.
443  *
444  * Returns false if no new arguments have been added.
445  */
446 int
447 another(int *pargc, char ***pargv, const char *prompt)
448 {
449 	int len = strlen(line), ret;
450 
451 	if (len >= sizeof(line) - 3) {
452 		fputs("sorry, arguments too long.\n", ttyout);
453 		intr(0);
454 	}
455 	fprintf(ttyout, "(%s) ", prompt);
456 	line[len++] = ' ';
457 	if (fgets(&line[len], sizeof(line) - len, stdin) == NULL) {
458 		clearerr(stdin);
459 		intr(0);
460 	}
461 	len += strlen(&line[len]);
462 	if (len > 0 && line[len - 1] == '\n')
463 		line[len - 1] = '\0';
464 	makeargv();
465 	ret = margc > *pargc;
466 	*pargc = margc;
467 	*pargv = margv;
468 	return (ret);
469 }
470 
471 /*
472  * glob files given in argv[] from the remote server.
473  * if errbuf isn't NULL, store error messages there instead
474  * of writing to the screen.
475  */
476 char *
477 remglob(char *argv[], int doswitch, char **errbuf)
478 {
479         char temp[MAXPATHLEN];
480         static char buf[MAXPATHLEN];
481         static FILE *ftemp = NULL;
482         static char **args;
483         int oldverbose, oldhash, fd, len;
484         char *cp, *mode;
485 
486         if (!mflag || !connected) {
487                 if (!doglob)
488                         args = NULL;
489                 else {
490                         if (ftemp) {
491                                 (void)fclose(ftemp);
492                                 ftemp = NULL;
493                         }
494                 }
495                 return (NULL);
496         }
497         if (!doglob) {
498                 if (args == NULL)
499                         args = argv;
500                 if ((cp = *++args) == NULL)
501                         args = NULL;
502                 return (cp);
503         }
504         if (ftemp == NULL) {
505 		len = strlcpy(temp, tmpdir, sizeof(temp));
506 		if (temp[len - 1] != '/')
507 			(void)strlcat(temp, "/", sizeof(temp));
508 		(void)strlcat(temp, TMPFILE, sizeof(temp));
509                 if ((fd = mkstemp(temp)) < 0) {
510                         warn("unable to create temporary file %s", temp);
511                         return (NULL);
512                 }
513                 close(fd);
514                 oldverbose = verbose;
515 		verbose = (errbuf != NULL) ? -1 : 0;
516                 oldhash = hash;
517                 hash = 0;
518                 if (doswitch)
519                         pswitch(!proxy);
520                 for (mode = "w"; *++argv != NULL; mode = "a")
521                         recvrequest("NLST", temp, *argv, mode, 0, 0);
522 		if ((code / 100) != COMPLETE) {
523 			if (errbuf != NULL)
524 				*errbuf = reply_string;
525 		}
526                 if (doswitch)
527                         pswitch(!proxy);
528                 verbose = oldverbose;
529 		hash = oldhash;
530                 ftemp = fopen(temp, "r");
531                 (void)unlink(temp);
532                 if (ftemp == NULL) {
533 			if (errbuf == NULL)
534 				fputs(
535 				    "can't find list of remote files, oops.\n",
536 				    ttyout);
537 			else
538 				*errbuf =
539 				    "can't find list of remote files, oops.";
540                         return (NULL);
541                 }
542         }
543         if (fgets(buf, sizeof(buf), ftemp) == NULL) {
544                 (void)fclose(ftemp);
545 		ftemp = NULL;
546                 return (NULL);
547         }
548         if ((cp = strchr(buf, '\n')) != NULL)
549                 *cp = '\0';
550         return (buf);
551 }
552 
553 /*
554  * Glob a local file name specification with the expectation of a single
555  * return value. Can't control multiple values being expanded from the
556  * expression, we return only the first.
557  * Returns NULL on error, or a pointer to a buffer containing the filename
558  * that's the caller's responsiblity to free(3) when finished with.
559  */
560 char *
561 globulize(const char *pattern)
562 {
563 	glob_t gl;
564 	int flags;
565 	char *p;
566 
567 	if (!doglob)
568 		return (xstrdup(pattern));
569 
570 	flags = GLOB_BRACE|GLOB_NOCHECK|GLOB_TILDE;
571 	memset(&gl, 0, sizeof(gl));
572 	if (glob(pattern, flags, NULL, &gl) || gl.gl_pathc == 0) {
573 		warnx("%s: not found", pattern);
574 		globfree(&gl);
575 		return (NULL);
576 	}
577 	p = xstrdup(gl.gl_pathv[0]);
578 	globfree(&gl);
579 	return (p);
580 }
581 
582 /*
583  * determine size of remote file
584  */
585 off_t
586 remotesize(const char *file, int noisy)
587 {
588 	int overbose;
589 	off_t size;
590 
591 	overbose = verbose;
592 	size = -1;
593 	if (debug == 0)
594 		verbose = -1;
595 	if (command("SIZE %s", file) == COMPLETE) {
596 		char *cp, *ep;
597 
598 		cp = strchr(reply_string, ' ');
599 		if (cp != NULL) {
600 			cp++;
601 #ifndef NO_QUAD
602 			size = strtoll(cp, &ep, 10);
603 #else
604 			size = strtol(cp, &ep, 10);
605 #endif
606 			if (*ep != '\0' && !isspace((unsigned char)*ep))
607 				size = -1;
608 		}
609 	} else if (noisy && debug == 0) {
610 		fputs(reply_string, ttyout);
611 		putc('\n', ttyout);
612 	}
613 	verbose = overbose;
614 	return (size);
615 }
616 
617 /*
618  * determine last modification time (in GMT) of remote file
619  */
620 time_t
621 remotemodtime(const char *file, int noisy)
622 {
623 	int overbose;
624 	time_t rtime;
625 	int ocode;
626 
627 	overbose = verbose;
628 	ocode = code;
629 	rtime = -1;
630 	if (debug == 0)
631 		verbose = -1;
632 	if (command("MDTM %s", file) == COMPLETE) {
633 		struct tm timebuf;
634 		char *timestr, *frac;
635 		int yy, mo, day, hour, min, sec;
636 
637 		/*
638 		 * time-val = 14DIGIT [ "." 1*DIGIT ]
639 		 *		YYYYMMDDHHMMSS[.sss]
640 		 * mdtm-response = "213" SP time-val CRLF / error-response
641 		 */
642 		timestr = reply_string + 4;
643 
644 					/*
645 					 * parse fraction.
646 					 * XXX: ignored for now
647 					 */
648 		frac = strchr(timestr, '\r');
649 		if (frac != NULL)
650 			*frac = '\0';
651 		frac = strchr(timestr, '.');
652 		if (frac != NULL)
653 			*frac++ = '\0';
654 		if (strlen(timestr) == 15 && strncmp(timestr, "191", 3) == 0) {
655 			/*
656 			 * XXX:	Workaround for lame ftpd's that return
657 			 *	`19100' instead of `2000'
658 			 */
659 			fprintf(ttyout,
660 	    "Y2K warning! Incorrect time-val `%s' received from server.\n",
661 			    timestr);
662 			timestr++;
663 			timestr[0] = '2';
664 			timestr[1] = '0';
665 			fprintf(ttyout, "Converted to `%s'\n", timestr);
666 		}
667 		if (strlen(timestr) != 14 ||
668 		    sscanf(timestr, "%04d%02d%02d%02d%02d%02d",
669 			&yy, &mo, &day, &hour, &min, &sec) != 6) {
670  bad_parse_time:
671 			fprintf(ttyout, "Can't parse time `%s'.\n", timestr);
672 			goto cleanup_parse_time;
673 		}
674 		memset(&timebuf, 0, sizeof(timebuf));
675 		timebuf.tm_sec = sec;
676 		timebuf.tm_min = min;
677 		timebuf.tm_hour = hour;
678 		timebuf.tm_mday = day;
679 		timebuf.tm_mon = mo - 1;
680 		timebuf.tm_year = yy - TM_YEAR_BASE;
681 		timebuf.tm_isdst = -1;
682 		rtime = timegm(&timebuf);
683 		if (rtime == -1) {
684 			if (noisy || debug != 0)
685 				goto bad_parse_time;
686 			else
687 				goto cleanup_parse_time;
688 		} else if (debug)
689 			fprintf(ttyout, "parsed date as: %s", ctime(&rtime));
690 	} else if (noisy && debug == 0) {
691 		fputs(reply_string, ttyout);
692 		putc('\n', ttyout);
693 	}
694  cleanup_parse_time:
695 	verbose = overbose;
696 	if (rtime == -1)
697 		code = ocode;
698 	return (rtime);
699 }
700 
701 /*
702  * update global `remotepwd', which contains the state of the remote cwd
703  */
704 void
705 updateremotepwd(void)
706 {
707 	int	 overbose, ocode, i;
708 	char	*cp;
709 
710 	overbose = verbose;
711 	ocode = code;
712 	if (debug == 0)
713 		verbose = -1;
714 	if (command("PWD") != COMPLETE)
715 		goto badremotepwd;
716 	cp = strchr(reply_string, ' ');
717 	if (cp == NULL || cp[0] == '\0' || cp[1] != '"')
718 		goto badremotepwd;
719 	cp += 2;
720 	for (i = 0; *cp && i < sizeof(remotepwd) - 1; i++, cp++) {
721 		if (cp[0] == '"') {
722 			if (cp[1] == '"')
723 				cp++;
724 			else
725 				break;
726 		}
727 		remotepwd[i] = *cp;
728 	}
729 	remotepwd[i] = '\0';
730 	if (debug)
731 		fprintf(ttyout, "got remotepwd as `%s'\n", remotepwd);
732 	goto cleanupremotepwd;
733  badremotepwd:
734 	remotepwd[0]='\0';
735  cleanupremotepwd:
736 	verbose = overbose;
737 	code = ocode;
738 }
739 
740 #ifndef	NO_PROGRESS
741 
742 /*
743  * return non-zero if we're the current foreground process
744  */
745 int
746 foregroundproc(void)
747 {
748 	static pid_t pgrp = -1;
749 
750 	if (pgrp == -1)
751 		pgrp = getpgrp();
752 
753 	return (tcgetpgrp(fileno(ttyout)) == pgrp);
754 }
755 
756 
757 static void updateprogressmeter(int);
758 
759 /*
760  * SIGALRM handler to update the progress meter
761  */
762 static void
763 updateprogressmeter(int dummy)
764 {
765 	int oerrno = errno;
766 
767 	progressmeter(0);
768 	errno = oerrno;
769 }
770 #endif	/* NO_PROGRESS */
771 
772 
773 /*
774  * List of order of magnitude prefixes.
775  * The last is `P', as 2^64 = 16384 Petabytes
776  */
777 static const char prefixes[] = " KMGTP";
778 
779 /*
780  * Display a transfer progress bar if progress is non-zero.
781  * SIGALRM is hijacked for use by this function.
782  * - Before the transfer, set filesize to size of file (or -1 if unknown),
783  *   and call with flag = -1. This starts the once per second timer,
784  *   and a call to updateprogressmeter() upon SIGALRM.
785  * - During the transfer, updateprogressmeter will call progressmeter
786  *   with flag = 0
787  * - After the transfer, call with flag = 1
788  */
789 static struct timeval start;
790 static struct timeval lastupdate;
791 
792 #define	BUFLEFT	(sizeof(buf) - len)
793 
794 void
795 progressmeter(int flag)
796 {
797 	static off_t lastsize;
798 #ifndef NO_PROGRESS
799 	struct timeval now, td, wait;
800 	off_t cursize, abbrevsize, bytespersec;
801 	double elapsed;
802 	int ratio, barlength, i, len, remaining;
803 
804 			/*
805 			 * Work variables for progress bar.
806 			 *
807 			 * XXX:	if the format of the progress bar changes
808 			 *	(especially the number of characters in the
809 			 *	`static' portion of it), be sure to update
810 			 *	these appropriately.
811 			 */
812 	char		buf[256];	/* workspace for progress bar */
813 #define	BAROVERHEAD	43		/* non `*' portion of progress bar */
814 					/*
815 					 * stars should contain at least
816 					 * sizeof(buf) - BAROVERHEAD entries
817 					 */
818 	const char	stars[] =
819 "*****************************************************************************"
820 "*****************************************************************************"
821 "*****************************************************************************";
822 
823 #endif
824 
825 	if (flag == -1) {
826 		(void)gettimeofday(&start, NULL);
827 		lastupdate = start;
828 		lastsize = restart_point;
829 	}
830 #ifndef NO_PROGRESS
831 	len = 0;
832 	if (!progress || filesize <= 0)
833 		return;
834 
835 	(void)gettimeofday(&now, NULL);
836 	cursize = bytes + restart_point;
837 	timersub(&now, &lastupdate, &wait);
838 	if (cursize > lastsize) {
839 		lastupdate = now;
840 		lastsize = cursize;
841 		wait.tv_sec = 0;
842 	}
843 
844 	/*
845 	 * print progress bar only if we are foreground process.
846 	 */
847 	if (! foregroundproc())
848 		return;
849 
850 	ratio = (int)((double)cursize * 100.0 / (double)filesize);
851 	ratio = MAX(ratio, 0);
852 	ratio = MIN(ratio, 100);
853 	len += snprintf(buf + len, BUFLEFT, "\r%3d%% ", ratio);
854 
855 			/*
856 			 * calculate the length of the `*' bar, ensuring that
857 			 * the number of stars won't exceed the buffer size
858 			 */
859 	barlength = MIN(sizeof(buf) - 1, ttywidth) - BAROVERHEAD;
860 	if (barlength > 0) {
861 		i = barlength * ratio / 100;
862 		len += snprintf(buf + len, BUFLEFT,
863 		    "|%.*s%*s|", i, stars, barlength - i, "");
864 	}
865 
866 	abbrevsize = cursize;
867 	for (i = 0; abbrevsize >= 100000 && i < sizeof(prefixes); i++)
868 		abbrevsize >>= 10;
869 	len += snprintf(buf + len, BUFLEFT,
870 #ifndef NO_QUAD
871 	    " %5lld %c%c ", (long long)abbrevsize,
872 #else
873 	    " %5ld %c%c ", (long)abbrevsize,
874 #endif
875 	    prefixes[i],
876 	    i == 0 ? ' ' : 'B');
877 
878 	timersub(&now, &start, &td);
879 	elapsed = td.tv_sec + (td.tv_usec / 1000000.0);
880 
881 	bytespersec = 0;
882 	if (bytes > 0) {
883 		bytespersec = bytes;
884 		if (elapsed > 0.0)
885 			bytespersec /= elapsed;
886 	}
887 	for (i = 1; bytespersec >= 1024000 && i < sizeof(prefixes); i++)
888 		bytespersec >>= 10;
889 	len += snprintf(buf + len, BUFLEFT,
890 #ifndef NO_QUAD
891 	    " %3lld.%02d %cB/s ", (long long)bytespersec / 1024,
892 #else
893 	    " %3ld.%02d %cB/s ", (long)bytespersec / 1024,
894 #endif
895 	    (int)((bytespersec % 1024) * 100 / 1024),
896 	    prefixes[i]);
897 
898 	if (bytes <= 0 || elapsed <= 0.0 || cursize > filesize) {
899 		len += snprintf(buf + len, BUFLEFT, "   --:-- ETA");
900 	} else if (wait.tv_sec >= STALLTIME) {
901 		len += snprintf(buf + len, BUFLEFT, " - stalled -");
902 	} else {
903 		remaining = (int)
904 		    ((filesize - restart_point) / (bytes / elapsed) - elapsed);
905 		if (remaining >= 100 * SECSPERHOUR)
906 			len += snprintf(buf + len, BUFLEFT, "   --:-- ETA");
907 		else {
908 			i = remaining / SECSPERHOUR;
909 			if (i)
910 				len += snprintf(buf + len, BUFLEFT, "%2d:", i);
911 			else
912 				len += snprintf(buf + len, BUFLEFT, "   ");
913 			i = remaining % SECSPERHOUR;
914 			len += snprintf(buf + len, BUFLEFT,
915 			    "%02d:%02d ETA", i / 60, i % 60);
916 		}
917 	}
918 	if (flag == 1)
919 		len += snprintf(buf + len, BUFLEFT, "\n");
920 	(void)write(fileno(ttyout), buf, len);
921 
922 	if (flag == -1) {
923 		(void)xsignal_restart(SIGALRM, updateprogressmeter, 1);
924 		alarmtimer(1);		/* set alarm timer for 1 Hz */
925 	} else if (flag == 1) {
926 		(void)xsignal(SIGALRM, SIG_DFL);
927 		alarmtimer(0);
928 	}
929 #endif	/* !NO_PROGRESS */
930 }
931 
932 /*
933  * Display transfer statistics.
934  * Requires start to be initialised by progressmeter(-1),
935  * direction to be defined by xfer routines, and filesize and bytes
936  * to be updated by xfer routines
937  * If siginfo is nonzero, an ETA is displayed, and the output goes to stderr
938  * instead of ttyout.
939  */
940 void
941 ptransfer(int siginfo)
942 {
943 	struct timeval now, td, wait;
944 	double elapsed;
945 	off_t bytespersec;
946 	int remaining, hh, i, len;
947 
948 	char buf[256];		/* Work variable for transfer status. */
949 
950 	if (!verbose && !progress && !siginfo)
951 		return;
952 
953 	(void)gettimeofday(&now, NULL);
954 	timersub(&now, &start, &td);
955 	elapsed = td.tv_sec + (td.tv_usec / 1000000.0);
956 	bytespersec = 0;
957 	if (bytes > 0) {
958 		bytespersec = bytes;
959 		if (elapsed > 0.0)
960 			bytespersec /= elapsed;
961 	}
962 	len = 0;
963 	len += snprintf(buf + len, BUFLEFT,
964 #ifndef NO_QUAD
965 	    "%lld byte%s %s in ", (long long)bytes,
966 #else
967 	    "%ld byte%s %s in ", (long)bytes,
968 #endif
969 	    bytes == 1 ? "" : "s", direction);
970 	remaining = (int)elapsed;
971 	if (remaining > SECSPERDAY) {
972 		int days;
973 
974 		days = remaining / SECSPERDAY;
975 		remaining %= SECSPERDAY;
976 		len += snprintf(buf + len, BUFLEFT,
977 		    "%d day%s ", days, days == 1 ? "" : "s");
978 	}
979 	hh = remaining / SECSPERHOUR;
980 	remaining %= SECSPERHOUR;
981 	if (hh)
982 		len += snprintf(buf + len, BUFLEFT, "%2d:", hh);
983 	len += snprintf(buf + len, BUFLEFT,
984 	    "%02d:%02d ", remaining / 60, remaining % 60);
985 
986 	for (i = 1; bytespersec >= 1024000 && i < sizeof(prefixes); i++)
987 		bytespersec >>= 10;
988 	len += snprintf(buf + len, BUFLEFT,
989 #ifndef NO_QUAD
990 	    "(%lld.%02d %cB/s)", (long long)bytespersec / 1024,
991 #else
992 	    "(%ld.%02d %cB/s)", (long)bytespersec / 1024,
993 #endif
994 	    (int)((bytespersec % 1024) * 100 / 1024),
995 	    prefixes[i]);
996 
997 	if (siginfo && bytes > 0 && elapsed > 0.0 && filesize >= 0
998 	    && bytes + restart_point <= filesize) {
999 		remaining = (int)((filesize - restart_point) /
1000 				  (bytes / elapsed) - elapsed);
1001 		hh = remaining / SECSPERHOUR;
1002 		remaining %= SECSPERHOUR;
1003 		len += snprintf(buf + len, BUFLEFT, "  ETA: ");
1004 		if (hh)
1005 			len += snprintf(buf + len, BUFLEFT, "%2d:", hh);
1006 		len += snprintf(buf + len, BUFLEFT, "%02d:%02d",
1007 		    remaining / 60, remaining % 60);
1008 		timersub(&now, &lastupdate, &wait);
1009 		if (wait.tv_sec >= STALLTIME)
1010 			len += snprintf(buf + len, BUFLEFT, "  (stalled)");
1011 	}
1012 	len += snprintf(buf + len, BUFLEFT, "\n");
1013 	(void)write(siginfo ? STDERR_FILENO : fileno(ttyout), buf, len);
1014 }
1015 
1016 /*
1017  * SIG{INFO,QUIT} handler to print transfer stats if a transfer is in progress
1018  */
1019 void
1020 psummary(int notused)
1021 {
1022 	int oerrno = errno;
1023 
1024 	if (bytes > 0) {
1025 		if (fromatty)
1026 			write(fileno(ttyout), "\n", 1);
1027 		ptransfer(1);
1028 	}
1029 	errno = oerrno;
1030 }
1031 
1032 /*
1033  * List words in stringlist, vertically arranged
1034  */
1035 void
1036 list_vertical(StringList *sl)
1037 {
1038 	int i, j, w;
1039 	int columns, width, lines, items;
1040 	char *p;
1041 
1042 	width = items = 0;
1043 
1044 	for (i = 0 ; i < sl->sl_cur ; i++) {
1045 		w = strlen(sl->sl_str[i]);
1046 		if (w > width)
1047 			width = w;
1048 	}
1049 	width = (width + 8) &~ 7;
1050 
1051 	columns = ttywidth / width;
1052 	if (columns == 0)
1053 		columns = 1;
1054 	lines = (sl->sl_cur + columns - 1) / columns;
1055 	for (i = 0; i < lines; i++) {
1056 		for (j = 0; j < columns; j++) {
1057 			p = sl->sl_str[j * lines + i];
1058 			if (p)
1059 				fputs(p, ttyout);
1060 			if (j * lines + i + lines >= sl->sl_cur) {
1061 				putc('\n', ttyout);
1062 				break;
1063 			}
1064 			w = strlen(p);
1065 			while (w < width) {
1066 				w = (w + 8) &~ 7;
1067 				(void)putc('\t', ttyout);
1068 			}
1069 		}
1070 	}
1071 }
1072 
1073 /*
1074  * Update the global ttywidth value, using TIOCGWINSZ.
1075  */
1076 void
1077 setttywidth(int a)
1078 {
1079 	struct winsize winsize;
1080 	int oerrno = errno;
1081 
1082 	if (ioctl(fileno(ttyout), TIOCGWINSZ, &winsize) != -1 &&
1083 	    winsize.ws_col != 0)
1084 		ttywidth = winsize.ws_col;
1085 	else
1086 		ttywidth = 80;
1087 	errno = oerrno;
1088 }
1089 
1090 /*
1091  * Change the rate limit up (SIGUSR1) or down (SIGUSR2)
1092  */
1093 void
1094 crankrate(int sig)
1095 {
1096 
1097 	switch (sig) {
1098 	case SIGUSR1:
1099 		if (rate_get)
1100 			rate_get += rate_get_incr;
1101 		if (rate_put)
1102 			rate_put += rate_put_incr;
1103 		break;
1104 	case SIGUSR2:
1105 		if (rate_get && rate_get > rate_get_incr)
1106 			rate_get -= rate_get_incr;
1107 		if (rate_put && rate_put > rate_put_incr)
1108 			rate_put -= rate_put_incr;
1109 		break;
1110 	default:
1111 		err(1, "crankrate invoked with unknown signal: %d", sig);
1112 	}
1113 }
1114 
1115 
1116 /*
1117  * Set the SIGALRM interval timer for wait seconds, 0 to disable.
1118  */
1119 void
1120 alarmtimer(int wait)
1121 {
1122 	struct itimerval itv;
1123 
1124 	itv.it_value.tv_sec = wait;
1125 	itv.it_value.tv_usec = 0;
1126 	itv.it_interval = itv.it_value;
1127 	setitimer(ITIMER_REAL, &itv, NULL);
1128 }
1129 
1130 /*
1131  * Setup or cleanup EditLine structures
1132  */
1133 #ifndef NO_EDITCOMPLETE
1134 void
1135 controlediting(void)
1136 {
1137 	if (editing && el == NULL && hist == NULL) {
1138 		HistEvent ev;
1139 		int editmode;
1140 
1141 		el = el_init(__progname, stdin, ttyout, stderr);
1142 		/* init editline */
1143 		hist = history_init();		/* init the builtin history */
1144 		history(hist, &ev, H_SETSIZE, 100);/* remember 100 events */
1145 		el_set(el, EL_HIST, history, hist);	/* use history */
1146 
1147 		el_set(el, EL_EDITOR, "emacs");	/* default editor is emacs */
1148 		el_set(el, EL_PROMPT, prompt);	/* set the prompt functions */
1149 		el_set(el, EL_RPROMPT, rprompt);
1150 
1151 		/* add local file completion, bind to TAB */
1152 		el_set(el, EL_ADDFN, "ftp-complete",
1153 		    "Context sensitive argument completion",
1154 		    complete);
1155 		el_set(el, EL_BIND, "^I", "ftp-complete", NULL);
1156 		el_source(el, NULL);	/* read ~/.editrc */
1157 		if ((el_get(el, EL_EDITMODE, &editmode) != -1) && editmode == 0)
1158 			editing = 0;	/* the user doesn't want editing,
1159 					 * so disable, and let statement
1160 					 * below cleanup */
1161 		else
1162 			el_set(el, EL_SIGNAL, 1);
1163 	}
1164 	if (!editing) {
1165 		if (hist) {
1166 			history_end(hist);
1167 			hist = NULL;
1168 		}
1169 		if (el) {
1170 			el_end(el);
1171 			el = NULL;
1172 		}
1173 	}
1174 }
1175 #endif /* !NO_EDITCOMPLETE */
1176 
1177 /*
1178  * Convert the string `arg' to an int, which may have an optional SI suffix
1179  * (`b', `k', `m', `g'). Returns the number for success, -1 otherwise.
1180  */
1181 int
1182 strsuftoi(const char *arg)
1183 {
1184 	char *cp;
1185 	long val;
1186 
1187 	if (!isdigit((unsigned char)arg[0]))
1188 		return (-1);
1189 
1190 	val = strtol(arg, &cp, 10);
1191 	if (cp != NULL) {
1192 		if (cp[0] != '\0' && cp[1] != '\0')
1193 			 return (-1);
1194 		switch (tolower((unsigned char)cp[0])) {
1195 		case '\0':
1196 		case 'b':
1197 			break;
1198 		case 'k':
1199 			val <<= 10;
1200 			break;
1201 		case 'm':
1202 			val <<= 20;
1203 			break;
1204 		case 'g':
1205 			val <<= 30;
1206 			break;
1207 		default:
1208 			return (-1);
1209 		}
1210 	}
1211 	if (val < 0 || val > INT_MAX)
1212 		return (-1);
1213 
1214 	return (val);
1215 }
1216 
1217 /*
1218  * Set up socket buffer sizes before a connection is made.
1219  */
1220 void
1221 setupsockbufsize(int sock)
1222 {
1223 
1224 	if (setsockopt(sock, SOL_SOCKET, SO_SNDBUF, (void *) &sndbuf_size,
1225 	    sizeof(rcvbuf_size)) < 0)
1226 		warn("unable to set sndbuf size %d", sndbuf_size);
1227 
1228 	if (setsockopt(sock, SOL_SOCKET, SO_RCVBUF, (void *) &rcvbuf_size,
1229 	    sizeof(rcvbuf_size)) < 0)
1230 		warn("unable to set rcvbuf size %d", rcvbuf_size);
1231 }
1232 
1233 /*
1234  * Copy characters from src into dst, \ quoting characters that require it
1235  */
1236 void
1237 ftpvis(char *dst, size_t dstlen, const char *src, size_t srclen)
1238 {
1239 	int	di, si;
1240 
1241 	for (di = si = 0;
1242 	    src[si] != '\0' && di < dstlen && si < srclen;
1243 	    di++, si++) {
1244 		switch (src[si]) {
1245 		case '\\':
1246 		case ' ':
1247 		case '\t':
1248 		case '\r':
1249 		case '\n':
1250 		case '"':
1251 			dst[di++] = '\\';
1252 			if (di >= dstlen)
1253 				break;
1254 			/* FALLTHROUGH */
1255 		default:
1256 			dst[di] = src[si];
1257 		}
1258 	}
1259 	dst[di] = '\0';
1260 }
1261 
1262 /*
1263  * Copy src into buf (which is len bytes long), expanding % sequences.
1264  */
1265 void
1266 formatbuf(char *buf, size_t len, const char *src)
1267 {
1268 	const char	*p;
1269 	char		*p2, *q;
1270 	int		 i, op, updirs, pdirs;
1271 
1272 #define ADDBUF(x) do { \
1273 		if (i >= len - 1) \
1274 			goto endbuf; \
1275 		buf[i++] = (x); \
1276 	} while (0)
1277 
1278 	p = src;
1279 	for (i = 0; *p; p++) {
1280 		if (*p != '%') {
1281 			ADDBUF(*p);
1282 			continue;
1283 		}
1284 		p++;
1285 
1286 		switch (op = *p) {
1287 
1288 		case '/':
1289 		case '.':
1290 		case 'c':
1291 			p2 = connected ? remotepwd : "";
1292 			updirs = pdirs = 0;
1293 
1294 			/* option to determine fixed # of dirs from path */
1295 			if (op == '.' || op == 'c') {
1296 				int skip;
1297 
1298 				q = p2;
1299 				while (*p2)		/* calc # of /'s */
1300 					if (*p2++ == '/')
1301 						updirs++;
1302 				if (p[1] == '0') {	/* print <x> or ... */
1303 					pdirs = 1;
1304 					p++;
1305 				}
1306 				if (p[1] >= '1' && p[1] <= '9') {
1307 							/* calc # to skip  */
1308 					skip = p[1] - '0';
1309 					p++;
1310 				} else
1311 					skip = 1;
1312 
1313 				updirs -= skip;
1314 				while (skip-- > 0) {
1315 					while ((p2 > q) && (*p2 != '/'))
1316 						p2--;	/* back up */
1317 					if (skip && p2 > q)
1318 						p2--;
1319 				}
1320 				if (*p2 == '/' && p2 != q)
1321 					p2++;
1322 			}
1323 
1324 			if (updirs > 0 && pdirs) {
1325 				if (i >= len - 5)
1326 					break;
1327 				if (op == '.') {
1328 					ADDBUF('.');
1329 					ADDBUF('.');
1330 					ADDBUF('.');
1331 				} else {
1332 					ADDBUF('/');
1333 					ADDBUF('<');
1334 					if (updirs > 9) {
1335 						ADDBUF('9');
1336 						ADDBUF('+');
1337 					} else
1338 						ADDBUF('0' + updirs);
1339 					ADDBUF('>');
1340 				}
1341 			}
1342 			for (; *p2; p2++)
1343 				ADDBUF(*p2);
1344 			break;
1345 
1346 		case 'M':
1347 		case 'm':
1348 			for (p2 = connected ? hostname : "-"; *p2; p2++) {
1349 				if (op == 'm' && *p2 == '.')
1350 					break;
1351 				ADDBUF(*p2);
1352 			}
1353 			break;
1354 
1355 		case 'n':
1356 			for (p2 = connected ? username : "-"; *p2 ; p2++)
1357 				ADDBUF(*p2);
1358 			break;
1359 
1360 		case '%':
1361 			ADDBUF('%');
1362 			break;
1363 
1364 		default:		/* display unknown codes literally */
1365 			ADDBUF('%');
1366 			ADDBUF(op);
1367 			break;
1368 
1369 		}
1370 	}
1371  endbuf:
1372 	buf[i] = '\0';
1373 }
1374 
1375 /*
1376  * Determine if given string is an IPv6 address or not.
1377  * Return 1 for yes, 0 for no
1378  */
1379 int
1380 isipv6addr(const char *addr)
1381 {
1382 	int rv = 0;
1383 #ifdef INET6
1384 	struct addrinfo hints, *res;
1385 
1386 	memset(&hints, 0, sizeof(hints));
1387 	hints.ai_family = PF_INET6;
1388 	hints.ai_socktype = SOCK_DGRAM;	/*dummy*/
1389 	hints.ai_flags = AI_NUMERICHOST;
1390 	if (getaddrinfo(addr, "0", &hints, &res) != 0)
1391 		rv = 0;
1392 	else {
1393 		rv = 1;
1394 		freeaddrinfo(res);
1395 	}
1396 	if (debug)
1397 		fprintf(ttyout, "isipv6addr: got %d for %s\n", rv, addr);
1398 #endif
1399 	return (rv == 1) ? 1 : 0;
1400 }
1401 
1402 
1403 /*
1404  * Internal version of connect(2); sets socket buffer sizes first.
1405  */
1406 int
1407 xconnect(int sock, const struct sockaddr *name, int namelen)
1408 {
1409 
1410 	setupsockbufsize(sock);
1411 	return (connect(sock, name, namelen));
1412 }
1413 
1414 /*
1415  * Internal version of listen(2); sets socket buffer sizes first.
1416  */
1417 int
1418 xlisten(int sock, int backlog)
1419 {
1420 
1421 	setupsockbufsize(sock);
1422 	return (listen(sock, backlog));
1423 }
1424 
1425 /*
1426  * malloc() with inbuilt error checking
1427  */
1428 void *
1429 xmalloc(size_t size)
1430 {
1431 	void *p;
1432 
1433 	p = malloc(size);
1434 	if (p == NULL)
1435 		err(1, "Unable to allocate %ld bytes of memory", (long)size);
1436 	return (p);
1437 }
1438 
1439 /*
1440  * sl_init() with inbuilt error checking
1441  */
1442 StringList *
1443 xsl_init(void)
1444 {
1445 	StringList *p;
1446 
1447 	p = sl_init();
1448 	if (p == NULL)
1449 		err(1, "Unable to allocate memory for stringlist");
1450 	return (p);
1451 }
1452 
1453 /*
1454  * sl_add() with inbuilt error checking
1455  */
1456 void
1457 xsl_add(StringList *sl, char *i)
1458 {
1459 
1460 	if (sl_add(sl, i) == -1)
1461 		err(1, "Unable to add `%s' to stringlist", i);
1462 }
1463 
1464 /*
1465  * strdup() with inbuilt error checking
1466  */
1467 char *
1468 xstrdup(const char *str)
1469 {
1470 	char *s;
1471 
1472 	if (str == NULL)
1473 		errx(1, "xstrdup() called with NULL argument");
1474 	s = strdup(str);
1475 	if (s == NULL)
1476 		err(1, "Unable to allocate memory for string copy");
1477 	return (s);
1478 }
1479 
1480 /*
1481  * Install a POSIX signal handler, allowing the invoker to set whether
1482  * the signal should be restartable or not
1483  */
1484 sigfunc
1485 xsignal_restart(int sig, sigfunc func, int restartable)
1486 {
1487 	struct sigaction act, oact;
1488 	act.sa_handler = func;
1489 
1490 	sigemptyset(&act.sa_mask);
1491 #if defined(SA_RESTART)			/* 4.4BSD, Posix(?), SVR4 */
1492 	act.sa_flags = restartable ? SA_RESTART : 0;
1493 #elif defined(SA_INTERRUPT)		/* SunOS 4.x */
1494 	act.sa_flags = restartable ? 0 : SA_INTERRUPT;
1495 #else
1496 #error "system must have SA_RESTART or SA_INTERRUPT"
1497 #endif
1498 	if (sigaction(sig, &act, &oact) < 0)
1499 		return (SIG_ERR);
1500 	return (oact.sa_handler);
1501 }
1502 
1503 /*
1504  * Install a signal handler with the `restartable' flag set dependent upon
1505  * which signal is being set. (This is a wrapper to xsignal_restart())
1506  */
1507 sigfunc
1508 xsignal(int sig, sigfunc func)
1509 {
1510 	int restartable;
1511 
1512 	/*
1513 	 * Some signals print output or change the state of the process.
1514 	 * There should be restartable, so that reads and writes are
1515 	 * not affected.  Some signals should cause program flow to change;
1516 	 * these signals should not be restartable, so that the system call
1517 	 * will return with EINTR, and the program will go do something
1518 	 * different.  If the signal handler calls longjmp() or siglongjmp(),
1519 	 * it doesn't matter if it's restartable.
1520 	 */
1521 
1522 	switch(sig) {
1523 #ifdef SIGINFO
1524 	case SIGINFO:
1525 #endif
1526 	case SIGQUIT:
1527 	case SIGUSR1:
1528 	case SIGUSR2:
1529 	case SIGWINCH:
1530 		restartable = 1;
1531 		break;
1532 
1533 	case SIGALRM:
1534 	case SIGINT:
1535 	case SIGPIPE:
1536 		restartable = 0;
1537 		break;
1538 
1539 	default:
1540 		/*
1541 		 * This is unpleasant, but I don't know what would be better.
1542 		 * Right now, this "can't happen"
1543 		 */
1544 		errx(1, "xsignal_restart called with signal %d", sig);
1545 	}
1546 
1547 	return(xsignal_restart(sig, func, restartable));
1548 }
1549