xref: /freebsd/usr.bin/xargs/xargs.c (revision a274be7720ee1956b2f2775c6e02da400c2475a2)
19b50d902SRodney W. Grimes /*-
29b50d902SRodney W. Grimes  * Copyright (c) 1990, 1993
39b50d902SRodney W. Grimes  *	The Regents of the University of California.  All rights reserved.
49b50d902SRodney W. Grimes  *
59b50d902SRodney W. Grimes  * This code is derived from software contributed to Berkeley by
69b50d902SRodney W. Grimes  * John B. Roll Jr.
79b50d902SRodney W. Grimes  *
89b50d902SRodney W. Grimes  * Redistribution and use in source and binary forms, with or without
99b50d902SRodney W. Grimes  * modification, are permitted provided that the following conditions
109b50d902SRodney W. Grimes  * are met:
119b50d902SRodney W. Grimes  * 1. Redistributions of source code must retain the above copyright
129b50d902SRodney W. Grimes  *    notice, this list of conditions and the following disclaimer.
139b50d902SRodney W. Grimes  * 2. Redistributions in binary form must reproduce the above copyright
149b50d902SRodney W. Grimes  *    notice, this list of conditions and the following disclaimer in the
159b50d902SRodney W. Grimes  *    documentation and/or other materials provided with the distribution.
169b50d902SRodney W. Grimes  * 4. Neither the name of the University nor the names of its contributors
179b50d902SRodney W. Grimes  *    may be used to endorse or promote products derived from this software
189b50d902SRodney W. Grimes  *    without specific prior written permission.
199b50d902SRodney W. Grimes  *
209b50d902SRodney W. Grimes  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
219b50d902SRodney W. Grimes  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
229b50d902SRodney W. Grimes  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
239b50d902SRodney W. Grimes  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
249b50d902SRodney W. Grimes  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
259b50d902SRodney W. Grimes  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
269b50d902SRodney W. Grimes  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
279b50d902SRodney W. Grimes  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
289b50d902SRodney W. Grimes  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
299b50d902SRodney W. Grimes  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
309b50d902SRodney W. Grimes  * SUCH DAMAGE.
31fc17b349SJuli Mallett  *
32fc17b349SJuli Mallett  * $xMach: xargs.c,v 1.6 2002/02/23 05:27:47 tim Exp $
339b50d902SRodney W. Grimes  */
349b50d902SRodney W. Grimes 
358eb2a3deSDavid E. O'Brien #if 0
36d7a43b24SJuli Mallett #ifndef lint
37d7a43b24SJuli Mallett static const char copyright[] =
38d7a43b24SJuli Mallett "@(#) Copyright (c) 1990, 1993\n\
39d7a43b24SJuli Mallett 	The Regents of the University of California.  All rights reserved.\n";
40d7a43b24SJuli Mallett #endif /* not lint */
41d7a43b24SJuli Mallett 
42d7a43b24SJuli Mallett #ifndef lint
43d7a43b24SJuli Mallett static char sccsid[] = "@(#)xargs.c	8.1 (Berkeley) 6/6/93";
44d7a43b24SJuli Mallett #endif /* not lint */
45d7a43b24SJuli Mallett #endif
4651883012SMike Barcroft #include <sys/cdefs.h>
4751883012SMike Barcroft __FBSDID("$FreeBSD$");
4851883012SMike Barcroft 
4940c6b893SRuslan Ermilov #include <sys/param.h>
509b50d902SRodney W. Grimes #include <sys/wait.h>
5116b07a33SMark Murray 
52a51024e2SPhilippe Charnier #include <err.h>
538ad749a4SDag-Erling Smørgrav #include <errno.h>
5498186e89SMaxime Henrion #include <fcntl.h>
55305e39f4SJuli Mallett #include <langinfo.h>
56305e39f4SJuli Mallett #include <locale.h>
57305e39f4SJuli Mallett #include <paths.h>
58305e39f4SJuli Mallett #include <regex.h>
599b50d902SRodney W. Grimes #include <stdio.h>
609b50d902SRodney W. Grimes #include <stdlib.h>
619b50d902SRodney W. Grimes #include <string.h>
629b50d902SRodney W. Grimes #include <unistd.h>
6316b07a33SMark Murray 
649b50d902SRodney W. Grimes #include "pathnames.h"
659b50d902SRodney W. Grimes 
661926d4aaSJuli Mallett static void	parse_input(int, char *[]);
671926d4aaSJuli Mallett static void	prerun(int, char *[]);
68305e39f4SJuli Mallett static int	prompt(void);
69fc17b349SJuli Mallett static void	run(char **);
7073385ac6SJuli Mallett static void	usage(void);
71fc17b349SJuli Mallett void		strnsubst(char **, const char *, const char *, size_t);
7292095ab6SStephen McKay static pid_t	xwait(int block, int *status);
7370945890SJilles Tjoelker static void	xexit(const char *, const int);
74330d23f5STim J. Robbins static void	waitchildren(const char *, int);
7592095ab6SStephen McKay static void	pids_init(void);
7692095ab6SStephen McKay static int	pids_empty(void);
7792095ab6SStephen McKay static int	pids_full(void);
7892095ab6SStephen McKay static void	pids_add(pid_t pid);
7992095ab6SStephen McKay static int	pids_remove(pid_t pid);
8092095ab6SStephen McKay static int	findslot(pid_t pid);
8192095ab6SStephen McKay static int	findfreeslot(void);
8292095ab6SStephen McKay static void	clearslot(int slot);
839b50d902SRodney W. Grimes 
8416b07a33SMark Murray static char echo[] = _PATH_ECHO;
858eb2a3deSDavid E. O'Brien static char **av, **bxp, **ep, **endxp, **xp;
8691045075SJuli Mallett static char *argp, *bbp, *ebp, *inpline, *p, *replstr;
8791045075SJuli Mallett static const char *eofstr;
8898186e89SMaxime Henrion static int count, insingle, indouble, oflag, pflag, tflag, Rflag, rval, zflag;
89ba084f6aSJuli Mallett static int cnt, Iflag, jfound, Lflag, Sflag, wasquoted, xflag;
90330d23f5STim J. Robbins static int curprocs, maxprocs;
9192095ab6SStephen McKay static pid_t *childpids;
92330d23f5STim J. Robbins 
93330d23f5STim J. Robbins static volatile int childerr;
9416b07a33SMark Murray 
9599a84ce1STim J. Robbins extern char **environ;
9673385ac6SJuli Mallett 
97a51024e2SPhilippe Charnier int
981926d4aaSJuli Mallett main(int argc, char *argv[])
999b50d902SRodney W. Grimes {
100a3e5bc4fSJoseph Koshy 	long arg_max;
10191045075SJuli Mallett 	int ch, Jflag, nargs, nflag, nline;
102fc17b349SJuli Mallett 	size_t linelen;
1033c675167SJuli Mallett 	char *endptr;
1049b50d902SRodney W. Grimes 
105fc17b349SJuli Mallett 	inpline = replstr = NULL;
10691045075SJuli Mallett 	ep = environ;
107fc17b349SJuli Mallett 	eofstr = "";
10891045075SJuli Mallett 	Jflag = nflag = 0;
1098d904f15SDima Dorfman 
110f58b94cbSTim J. Robbins 	(void)setlocale(LC_ALL, "");
111305e39f4SJuli Mallett 
1129b50d902SRodney W. Grimes 	/*
1139b50d902SRodney W. Grimes 	 * POSIX.2 limits the exec line length to ARG_MAX - 2K.  Running that
1149b50d902SRodney W. Grimes 	 * caused some E2BIG errors, so it was changed to ARG_MAX - 4K.  Given
1159b50d902SRodney W. Grimes 	 * that the smallest argument is 2 bytes in length, this means that
1169b50d902SRodney W. Grimes 	 * the number of arguments is limited to:
1179b50d902SRodney W. Grimes 	 *
1189b50d902SRodney W. Grimes 	 *	 (ARG_MAX - 4K - LENGTH(utility + arguments)) / 2.
1199b50d902SRodney W. Grimes 	 *
1209b50d902SRodney W. Grimes 	 * We arbitrarily limit the number of arguments to 5000.  This is
1219b50d902SRodney W. Grimes 	 * allowed by POSIX.2 as long as the resulting minimum exec line is
1229b50d902SRodney W. Grimes 	 * at least LINE_MAX.  Realloc'ing as necessary is possible, but
1239b50d902SRodney W. Grimes 	 * probably not worthwhile.
1249b50d902SRodney W. Grimes 	 */
1259b50d902SRodney W. Grimes 	nargs = 5000;
126a3e5bc4fSJoseph Koshy 	if ((arg_max = sysconf(_SC_ARG_MAX)) == -1)
127a3e5bc4fSJoseph Koshy 		errx(1, "sysconf(_SC_ARG_MAX) failed");
128a3e5bc4fSJoseph Koshy 	nline = arg_max - 4 * 1024;
12991045075SJuli Mallett 	while (*ep != NULL) {
130e5009da0SSatoshi Asami 		/* 1 byte for each '\0' */
131e5009da0SSatoshi Asami 		nline -= strlen(*ep++) + 1 + sizeof(*ep);
132e5009da0SSatoshi Asami 	}
133330d23f5STim J. Robbins 	maxprocs = 1;
134ba084f6aSJuli Mallett 	while ((ch = getopt(argc, argv, "0E:I:J:L:n:oP:pR:S:s:rtx")) != -1)
1359b50d902SRodney W. Grimes 		switch (ch) {
136fc17b349SJuli Mallett 		case 'E':
137fc17b349SJuli Mallett 			eofstr = optarg;
138fc17b349SJuli Mallett 			break;
139fc17b349SJuli Mallett 		case 'I':
1406ea89183SJuli Mallett 			Jflag = 0;
141fc17b349SJuli Mallett 			Iflag = 1;
1424f49da74SJuli Mallett 			Lflag = 1;
143fc17b349SJuli Mallett 			replstr = optarg;
144fc17b349SJuli Mallett 			break;
1458d904f15SDima Dorfman 		case 'J':
1466ea89183SJuli Mallett 			Iflag = 0;
147b50a7286SJuli Mallett 			Jflag = 1;
1488d904f15SDima Dorfman 			replstr = optarg;
1498d904f15SDima Dorfman 			break;
150fc17b349SJuli Mallett 		case 'L':
1514f49da74SJuli Mallett 			Lflag = atoi(optarg);
152fc17b349SJuli Mallett 			break;
1539b50d902SRodney W. Grimes 		case 'n':
1549b50d902SRodney W. Grimes 			nflag = 1;
1559b50d902SRodney W. Grimes 			if ((nargs = atoi(optarg)) <= 0)
156a51024e2SPhilippe Charnier 				errx(1, "illegal argument count");
1579b50d902SRodney W. Grimes 			break;
15898186e89SMaxime Henrion 		case 'o':
15998186e89SMaxime Henrion 			oflag = 1;
16098186e89SMaxime Henrion 			break;
161330d23f5STim J. Robbins 		case 'P':
162330d23f5STim J. Robbins 			if ((maxprocs = atoi(optarg)) <= 0)
163330d23f5STim J. Robbins 				errx(1, "max. processes must be >0");
164330d23f5STim J. Robbins 			break;
165fc17b349SJuli Mallett 		case 'p':
166fc17b349SJuli Mallett 			pflag = 1;
167fc17b349SJuli Mallett 			break;
168b50a7286SJuli Mallett 		case 'R':
1693c675167SJuli Mallett 			Rflag = strtol(optarg, &endptr, 10);
1703c675167SJuli Mallett 			if (*endptr != '\0')
1713c675167SJuli Mallett 				errx(1, "replacements must be a number");
172b50a7286SJuli Mallett 			break;
1732d14e0e5SDag-Erling Smørgrav 		case 'r':
1742d14e0e5SDag-Erling Smørgrav 			/* GNU compatibility */
1752d14e0e5SDag-Erling Smørgrav 			break;
176ba084f6aSJuli Mallett 		case 'S':
177ba084f6aSJuli Mallett 			Sflag = strtoul(optarg, &endptr, 10);
178ba084f6aSJuli Mallett 			if (*endptr != '\0')
179ba084f6aSJuli Mallett 				errx(1, "replsize must be a number");
180ba084f6aSJuli Mallett 			break;
1819b50d902SRodney W. Grimes 		case 's':
1829b50d902SRodney W. Grimes 			nline = atoi(optarg);
1839b50d902SRodney W. Grimes 			break;
1849b50d902SRodney W. Grimes 		case 't':
1859b50d902SRodney W. Grimes 			tflag = 1;
1869b50d902SRodney W. Grimes 			break;
1879b50d902SRodney W. Grimes 		case 'x':
1889b50d902SRodney W. Grimes 			xflag = 1;
1899b50d902SRodney W. Grimes 			break;
190d9198881SWarner Losh 		case '0':
191d9198881SWarner Losh 			zflag = 1;
192d9198881SWarner Losh 			break;
1939b50d902SRodney W. Grimes 		case '?':
1949b50d902SRodney W. Grimes 		default:
1959b50d902SRodney W. Grimes 			usage();
1969b50d902SRodney W. Grimes 	}
1979b50d902SRodney W. Grimes 	argc -= optind;
1989b50d902SRodney W. Grimes 	argv += optind;
1999b50d902SRodney W. Grimes 
2006ea89183SJuli Mallett 	if (!Iflag && Rflag)
2016ea89183SJuli Mallett 		usage();
202ba084f6aSJuli Mallett 	if (!Iflag && Sflag)
203ba084f6aSJuli Mallett 		usage();
2046ea89183SJuli Mallett 	if (Iflag && !Rflag)
2056ea89183SJuli Mallett 		Rflag = 5;
206ba084f6aSJuli Mallett 	if (Iflag && !Sflag)
207ba084f6aSJuli Mallett 		Sflag = 255;
2089b50d902SRodney W. Grimes 	if (xflag && !nflag)
2099b50d902SRodney W. Grimes 		usage();
2104f49da74SJuli Mallett 	if (Iflag || Lflag)
211fc17b349SJuli Mallett 		xflag = 1;
212fc17b349SJuli Mallett 	if (replstr != NULL && *replstr == '\0')
213fc17b349SJuli Mallett 		errx(1, "replstr may not be empty");
2149b50d902SRodney W. Grimes 
21592095ab6SStephen McKay 	pids_init();
21692095ab6SStephen McKay 
2179b50d902SRodney W. Grimes 	/*
2189b50d902SRodney W. Grimes 	 * Allocate pointers for the utility name, the utility arguments,
2199b50d902SRodney W. Grimes 	 * the maximum arguments to be read from stdin and the trailing
2209b50d902SRodney W. Grimes 	 * NULL.
2219b50d902SRodney W. Grimes 	 */
222fc17b349SJuli Mallett 	linelen = 1 + argc + nargs + 1;
2230fa5e8dcSJuli Mallett 	if ((av = bxp = malloc(linelen * sizeof(char **))) == NULL)
22491045075SJuli Mallett 		errx(1, "malloc failed");
2259b50d902SRodney W. Grimes 
2269b50d902SRodney W. Grimes 	/*
2279b50d902SRodney W. Grimes 	 * Use the user's name for the utility as argv[0], just like the
2289b50d902SRodney W. Grimes 	 * shell.  Echo is the default.  Set up pointers for the user's
2299b50d902SRodney W. Grimes 	 * arguments.
2309b50d902SRodney W. Grimes 	 */
2313dca1afcSJuli Mallett 	if (*argv == NULL)
2329bf450b8SJuli Mallett 		cnt = strlen(*bxp++ = echo);
2339b50d902SRodney W. Grimes 	else {
2349b50d902SRodney W. Grimes 		do {
235b50a7286SJuli Mallett 			if (Jflag && strcmp(*argv, replstr) == 0) {
23691045075SJuli Mallett 				char **avj;
2378d904f15SDima Dorfman 				jfound = 1;
2388d904f15SDima Dorfman 				argv++;
2398d904f15SDima Dorfman 				for (avj = argv; *avj; avj++)
2408d904f15SDima Dorfman 					cnt += strlen(*avj) + 1;
2418d904f15SDima Dorfman 				break;
2428d904f15SDima Dorfman 			}
2439b50d902SRodney W. Grimes 			cnt += strlen(*bxp++ = *argv) + 1;
2443dca1afcSJuli Mallett 		} while (*++argv != NULL);
2459b50d902SRodney W. Grimes 	}
2469b50d902SRodney W. Grimes 
2479b50d902SRodney W. Grimes 	/*
2489b50d902SRodney W. Grimes 	 * Set up begin/end/traversing pointers into the array.  The -n
2499b50d902SRodney W. Grimes 	 * count doesn't include the trailing NULL pointer, so the malloc
2509b50d902SRodney W. Grimes 	 * added in an extra slot.
2519b50d902SRodney W. Grimes 	 */
2528eb2a3deSDavid E. O'Brien 	endxp = (xp = bxp) + nargs;
2539b50d902SRodney W. Grimes 
2549b50d902SRodney W. Grimes 	/*
2559b50d902SRodney W. Grimes 	 * Allocate buffer space for the arguments read from stdin and the
2569b50d902SRodney W. Grimes 	 * trailing NULL.  Buffer space is defined as the default or specified
2579b50d902SRodney W. Grimes 	 * space, minus the length of the utility name and arguments.  Set up
2589b50d902SRodney W. Grimes 	 * begin/end/traversing pointers into the array.  The -s count does
2599b50d902SRodney W. Grimes 	 * include the trailing NULL, so the malloc didn't add in an extra
2609b50d902SRodney W. Grimes 	 * slot.
2619b50d902SRodney W. Grimes 	 */
2629b50d902SRodney W. Grimes 	nline -= cnt;
2639b50d902SRodney W. Grimes 	if (nline <= 0)
264a51024e2SPhilippe Charnier 		errx(1, "insufficient space for command");
2659b50d902SRodney W. Grimes 
2669bf450b8SJuli Mallett 	if ((bbp = malloc((size_t)(nline + 1))) == NULL)
26791045075SJuli Mallett 		errx(1, "malloc failed");
2689b50d902SRodney W. Grimes 	ebp = (argp = p = bbp) + nline - 1;
26991045075SJuli Mallett 	for (;;)
27091045075SJuli Mallett 		parse_input(argc, argv);
27191045075SJuli Mallett }
2729b50d902SRodney W. Grimes 
27391045075SJuli Mallett static void
2741926d4aaSJuli Mallett parse_input(int argc, char *argv[])
27591045075SJuli Mallett {
27691045075SJuli Mallett 	int ch, foundeof;
27791045075SJuli Mallett 	char **avj;
27891045075SJuli Mallett 
27991045075SJuli Mallett 	foundeof = 0;
28091045075SJuli Mallett 
2819b50d902SRodney W. Grimes 	switch (ch = getchar()) {
2829b50d902SRodney W. Grimes 	case EOF:
2839b50d902SRodney W. Grimes 		/* No arguments since last exec. */
28470945890SJilles Tjoelker 		if (p == bbp)
28570945890SJilles Tjoelker 			xexit(*av, rval);
2869b50d902SRodney W. Grimes 		goto arg1;
2879b50d902SRodney W. Grimes 	case ' ':
2889b50d902SRodney W. Grimes 	case '\t':
2899b50d902SRodney W. Grimes 		/* Quotes escape tabs and spaces. */
290d9198881SWarner Losh 		if (insingle || indouble || zflag)
2919b50d902SRodney W. Grimes 			goto addch;
2929b50d902SRodney W. Grimes 		goto arg2;
293d9198881SWarner Losh 	case '\0':
29446793db9SGarance A Drosehn 		if (zflag) {
29546793db9SGarance A Drosehn 			/*
29646793db9SGarance A Drosehn 			 * Increment 'count', so that nulls will be treated
29746793db9SGarance A Drosehn 			 * as end-of-line, as well as end-of-argument.  This
29846793db9SGarance A Drosehn 			 * is needed so -0 works properly with -I and -L.
29946793db9SGarance A Drosehn 			 */
30046793db9SGarance A Drosehn 			count++;
301d9198881SWarner Losh 			goto arg2;
30246793db9SGarance A Drosehn 		}
303d9198881SWarner Losh 		goto addch;
3049b50d902SRodney W. Grimes 	case '\n':
305d9198881SWarner Losh 		if (zflag)
306d9198881SWarner Losh 			goto addch;
30746793db9SGarance A Drosehn 		count++;	    /* Indicate end-of-line (used by -L) */
308d9198881SWarner Losh 
3099b50d902SRodney W. Grimes 		/* Quotes do not escape newlines. */
31070945890SJilles Tjoelker arg1:		if (insingle || indouble) {
31170945890SJilles Tjoelker 			warnx("unterminated quote");
31270945890SJilles Tjoelker 			xexit(*av, 1);
31370945890SJilles Tjoelker 		}
314ef9866beSJean-Marc Zucconi arg2:
315fc17b349SJuli Mallett 		foundeof = *eofstr != '\0' &&
3164aeb6382SJuli Mallett 		    strncmp(argp, eofstr, p - argp) == 0;
317fc17b349SJuli Mallett 
318ef9866beSJean-Marc Zucconi 		/* Do not make empty args unless they are quoted */
319fc17b349SJuli Mallett 		if ((argp != p || wasquoted) && !foundeof) {
320ef9866beSJean-Marc Zucconi 			*p++ = '\0';
3219b50d902SRodney W. Grimes 			*xp++ = argp;
322fc17b349SJuli Mallett 			if (Iflag) {
323fc17b349SJuli Mallett 				size_t curlen;
324b9b03ba0SJuli Mallett 
325b9b03ba0SJuli Mallett 				if (inpline == NULL)
326fc17b349SJuli Mallett 					curlen = 0;
327fc17b349SJuli Mallett 				else {
3281925cb24SJuli Mallett 					/*
3291925cb24SJuli Mallett 					 * If this string is not zero
3301925cb24SJuli Mallett 					 * length, append a space for
3312b239dd1SJens Schweikhardt 					 * separation before the next
3321925cb24SJuli Mallett 					 * argument.
3331925cb24SJuli Mallett 					 */
334b9b03ba0SJuli Mallett 					if ((curlen = strlen(inpline)))
335fc17b349SJuli Mallett 						strcat(inpline, " ");
336fc17b349SJuli Mallett 				}
337fc17b349SJuli Mallett 				curlen++;
3381925cb24SJuli Mallett 				/*
3391925cb24SJuli Mallett 				 * Allocate enough to hold what we will
3405eb40323SJuli Mallett 				 * be holding in a second, and to append
3411925cb24SJuli Mallett 				 * a space next time through, if we have
3421925cb24SJuli Mallett 				 * to.
3431925cb24SJuli Mallett 				 */
344b9b03ba0SJuli Mallett 				inpline = realloc(inpline, curlen + 2 +
345b9b03ba0SJuli Mallett 				    strlen(argp));
34670945890SJilles Tjoelker 				if (inpline == NULL) {
34770945890SJilles Tjoelker 					warnx("realloc failed");
34870945890SJilles Tjoelker 					xexit(*av, 1);
34970945890SJilles Tjoelker 				}
350fc17b349SJuli Mallett 				if (curlen == 1)
351fc17b349SJuli Mallett 					strcpy(inpline, argp);
352fc17b349SJuli Mallett 				else
353fc17b349SJuli Mallett 					strcat(inpline, argp);
354fc17b349SJuli Mallett 			}
355ef9866beSJean-Marc Zucconi 		}
3569b50d902SRodney W. Grimes 
3579b50d902SRodney W. Grimes 		/*
3589b50d902SRodney W. Grimes 		 * If max'd out on args or buffer, or reached EOF,
3599b50d902SRodney W. Grimes 		 * run the command.  If xflag and max'd out on buffer
3601925cb24SJuli Mallett 		 * but not on args, object.  Having reached the limit
3611925cb24SJuli Mallett 		 * of input lines, as specified by -L is the same as
3621925cb24SJuli Mallett 		 * maxing out on arguments.
3639b50d902SRodney W. Grimes 		 */
3648eb2a3deSDavid E. O'Brien 		if (xp == endxp || p > ebp || ch == EOF ||
3655eb40323SJuli Mallett 		    (Lflag <= count && xflag) || foundeof) {
36670945890SJilles Tjoelker 			if (xflag && xp != endxp && p > ebp) {
36770945890SJilles Tjoelker 				warnx("insufficient space for arguments");
36870945890SJilles Tjoelker 				xexit(*av, 1);
36970945890SJilles Tjoelker 			}
3708d904f15SDima Dorfman 			if (jfound) {
3718d904f15SDima Dorfman 				for (avj = argv; *avj; avj++)
3728d904f15SDima Dorfman 					*xp++ = *avj;
3738d904f15SDima Dorfman 			}
37491045075SJuli Mallett 			prerun(argc, av);
37570945890SJilles Tjoelker 			if (ch == EOF || foundeof)
37670945890SJilles Tjoelker 				xexit(*av, rval);
3779b50d902SRodney W. Grimes 			p = bbp;
3789b50d902SRodney W. Grimes 			xp = bxp;
379fc17b349SJuli Mallett 			count = 0;
380ef9866beSJean-Marc Zucconi 		}
3819b50d902SRodney W. Grimes 		argp = p;
382ef9866beSJean-Marc Zucconi 		wasquoted = 0;
3839b50d902SRodney W. Grimes 		break;
3849b50d902SRodney W. Grimes 	case '\'':
385d9198881SWarner Losh 		if (indouble || zflag)
3869b50d902SRodney W. Grimes 			goto addch;
3879b50d902SRodney W. Grimes 		insingle = !insingle;
388ef9866beSJean-Marc Zucconi 		wasquoted = 1;
3899b50d902SRodney W. Grimes 		break;
3909b50d902SRodney W. Grimes 	case '"':
391d9198881SWarner Losh 		if (insingle || zflag)
3929b50d902SRodney W. Grimes 			goto addch;
3939b50d902SRodney W. Grimes 		indouble = !indouble;
394ef9866beSJean-Marc Zucconi 		wasquoted = 1;
3959b50d902SRodney W. Grimes 		break;
3969b50d902SRodney W. Grimes 	case '\\':
397d9198881SWarner Losh 		if (zflag)
398d9198881SWarner Losh 			goto addch;
3999b50d902SRodney W. Grimes 		/* Backslash escapes anything, is escaped by quotes. */
40070945890SJilles Tjoelker 		if (!insingle && !indouble && (ch = getchar()) == EOF) {
40170945890SJilles Tjoelker 			warnx("backslash at EOF");
40270945890SJilles Tjoelker 			xexit(*av, 1);
40370945890SJilles Tjoelker 		}
4049b50d902SRodney W. Grimes 		/* FALLTHROUGH */
4059b50d902SRodney W. Grimes 	default:
4069b50d902SRodney W. Grimes addch:		if (p < ebp) {
4079b50d902SRodney W. Grimes 			*p++ = ch;
4089b50d902SRodney W. Grimes 			break;
4099b50d902SRodney W. Grimes 		}
4109b50d902SRodney W. Grimes 
4119b50d902SRodney W. Grimes 		/* If only one argument, not enough buffer space. */
41270945890SJilles Tjoelker 		if (bxp == xp) {
41370945890SJilles Tjoelker 			warnx("insufficient space for argument");
41470945890SJilles Tjoelker 			xexit(*av, 1);
41570945890SJilles Tjoelker 		}
4169b50d902SRodney W. Grimes 		/* Didn't hit argument limit, so if xflag object. */
41770945890SJilles Tjoelker 		if (xflag) {
41870945890SJilles Tjoelker 			warnx("insufficient space for arguments");
41970945890SJilles Tjoelker 			xexit(*av, 1);
42070945890SJilles Tjoelker 		}
4219b50d902SRodney W. Grimes 
4228d904f15SDima Dorfman 		if (jfound) {
4238d904f15SDima Dorfman 			for (avj = argv; *avj; avj++)
4248d904f15SDima Dorfman 				*xp++ = *avj;
4258d904f15SDima Dorfman 		}
42691045075SJuli Mallett 		prerun(argc, av);
4279b50d902SRodney W. Grimes 		xp = bxp;
4289b50d902SRodney W. Grimes 		cnt = ebp - argp;
429fc17b349SJuli Mallett 		memcpy(bbp, argp, (size_t)cnt);
4309b50d902SRodney W. Grimes 		p = (argp = bbp) + cnt;
4319b50d902SRodney W. Grimes 		*p++ = ch;
4329b50d902SRodney W. Grimes 		break;
4339b50d902SRodney W. Grimes 	}
4349b50d902SRodney W. Grimes }
4359b50d902SRodney W. Grimes 
436263dc775SJuli Mallett /*
437263dc775SJuli Mallett  * Do things necessary before run()'ing, such as -I substitution,
438263dc775SJuli Mallett  * and then call run().
439263dc775SJuli Mallett  */
440263dc775SJuli Mallett static void
4411926d4aaSJuli Mallett prerun(int argc, char *argv[])
442263dc775SJuli Mallett {
443263dc775SJuli Mallett 	char **tmp, **tmp2, **avj;
44491045075SJuli Mallett 	int repls;
44591045075SJuli Mallett 
44691045075SJuli Mallett 	repls = Rflag;
447263dc775SJuli Mallett 
448be70f7d4SJuli Mallett 	if (argc == 0 || repls == 0) {
449263dc775SJuli Mallett 		*xp = NULL;
450263dc775SJuli Mallett 		run(argv);
451263dc775SJuli Mallett 		return;
452263dc775SJuli Mallett 	}
453263dc775SJuli Mallett 
454263dc775SJuli Mallett 	avj = argv;
455263dc775SJuli Mallett 
456263dc775SJuli Mallett 	/*
457263dc775SJuli Mallett 	 * Allocate memory to hold the argument list, and
458263dc775SJuli Mallett 	 * a NULL at the tail.
459263dc775SJuli Mallett 	 */
460b6594dbaSJuli Mallett 	tmp = malloc((argc + 1) * sizeof(char**));
46170945890SJilles Tjoelker 	if (tmp == NULL) {
46270945890SJilles Tjoelker 		warnx("malloc failed");
46370945890SJilles Tjoelker 		xexit(*argv, 1);
46470945890SJilles Tjoelker 	}
465263dc775SJuli Mallett 	tmp2 = tmp;
466263dc775SJuli Mallett 
467263dc775SJuli Mallett 	/*
468263dc775SJuli Mallett 	 * Save the first argument and iterate over it, we
469263dc775SJuli Mallett 	 * cannot do strnsubst() to it.
470263dc775SJuli Mallett 	 */
47170945890SJilles Tjoelker 	if ((*tmp++ = strdup(*avj++)) == NULL) {
47270945890SJilles Tjoelker 		warnx("strdup failed");
47370945890SJilles Tjoelker 		xexit(*argv, 1);
47470945890SJilles Tjoelker 	}
475263dc775SJuli Mallett 
476263dc775SJuli Mallett 	/*
477263dc775SJuli Mallett 	 * For each argument to utility, if we have not used up
478263dc775SJuli Mallett 	 * the number of replacements we are allowed to do, and
4792b239dd1SJens Schweikhardt 	 * if the argument contains at least one occurrence of
480263dc775SJuli Mallett 	 * replstr, call strnsubst(), else just save the string.
481263dc775SJuli Mallett 	 * Iterations over elements of avj and tmp are done
482263dc775SJuli Mallett 	 * where appropriate.
483263dc775SJuli Mallett 	 */
484263dc775SJuli Mallett 	while (--argc) {
485263dc775SJuli Mallett 		*tmp = *avj++;
486263dc775SJuli Mallett 		if (repls && strstr(*tmp, replstr) != NULL) {
487ba084f6aSJuli Mallett 			strnsubst(tmp++, replstr, inpline, (size_t)Sflag);
4883c675167SJuli Mallett 			if (repls > 0)
489263dc775SJuli Mallett 				repls--;
490263dc775SJuli Mallett 		} else {
49170945890SJilles Tjoelker 			if ((*tmp = strdup(*tmp)) == NULL) {
49270945890SJilles Tjoelker 				warnx("strdup failed");
49370945890SJilles Tjoelker 				xexit(*argv, 1);
49470945890SJilles Tjoelker 			}
495263dc775SJuli Mallett 			tmp++;
496263dc775SJuli Mallett 		}
497263dc775SJuli Mallett 	}
498263dc775SJuli Mallett 
499263dc775SJuli Mallett 	/*
500263dc775SJuli Mallett 	 * Run it.
501263dc775SJuli Mallett 	 */
502b6594dbaSJuli Mallett 	*tmp = NULL;
503263dc775SJuli Mallett 	run(tmp2);
504263dc775SJuli Mallett 
505263dc775SJuli Mallett 	/*
506263dc775SJuli Mallett 	 * Walk from the tail to the head, free along the way.
507263dc775SJuli Mallett 	 */
508263dc775SJuli Mallett 	for (; tmp2 != tmp; tmp--)
509263dc775SJuli Mallett 		free(*tmp);
510263dc775SJuli Mallett 	/*
511263dc775SJuli Mallett 	 * Now free the list itself.
512263dc775SJuli Mallett 	 */
513263dc775SJuli Mallett 	free(tmp2);
514263dc775SJuli Mallett 
515263dc775SJuli Mallett 	/*
516986d829bSJuli Mallett 	 * Free the input line buffer, if we have one.
517263dc775SJuli Mallett 	 */
51851f7a48bSJuli Mallett 	if (inpline != NULL) {
51991045075SJuli Mallett 		free(inpline);
52051f7a48bSJuli Mallett 		inpline = NULL;
52151f7a48bSJuli Mallett 	}
522263dc775SJuli Mallett }
523263dc775SJuli Mallett 
524fc17b349SJuli Mallett static void
52573385ac6SJuli Mallett run(char **argv)
5269b50d902SRodney W. Grimes {
5279b50d902SRodney W. Grimes 	pid_t pid;
5280792992cSMaxime Henrion 	int fd;
529330d23f5STim J. Robbins 	char **avec;
5309b50d902SRodney W. Grimes 
531305e39f4SJuli Mallett 	/*
532305e39f4SJuli Mallett 	 * If the user wants to be notified of each command before it is
533305e39f4SJuli Mallett 	 * executed, notify them.  If they want the notification to be
534305e39f4SJuli Mallett 	 * followed by a prompt, then prompt them.
535305e39f4SJuli Mallett 	 */
536fc17b349SJuli Mallett 	if (tflag || pflag) {
5379b50d902SRodney W. Grimes 		(void)fprintf(stderr, "%s", *argv);
53891045075SJuli Mallett 		for (avec = argv + 1; *avec != NULL; ++avec)
53991045075SJuli Mallett 			(void)fprintf(stderr, " %s", *avec);
540305e39f4SJuli Mallett 		/*
541305e39f4SJuli Mallett 		 * If the user has asked to be prompted, do so.
542305e39f4SJuli Mallett 		 */
543305e39f4SJuli Mallett 		if (pflag)
544305e39f4SJuli Mallett 			/*
545305e39f4SJuli Mallett 			 * If they asked not to exec, return without execution
546305e39f4SJuli Mallett 			 * but if they asked to, go to the execution.  If we
547305e39f4SJuli Mallett 			 * could not open their tty, break the switch and drop
548305e39f4SJuli Mallett 			 * back to -t behaviour.
549305e39f4SJuli Mallett 			 */
550305e39f4SJuli Mallett 			switch (prompt()) {
551305e39f4SJuli Mallett 			case 0:
552fc17b349SJuli Mallett 				return;
553305e39f4SJuli Mallett 			case 1:
554305e39f4SJuli Mallett 				goto exec;
555305e39f4SJuli Mallett 			case 2:
556305e39f4SJuli Mallett 				break;
557305e39f4SJuli Mallett 			}
5589b50d902SRodney W. Grimes 		(void)fprintf(stderr, "\n");
5599b50d902SRodney W. Grimes 		(void)fflush(stderr);
5609b50d902SRodney W. Grimes 	}
561305e39f4SJuli Mallett exec:
5628ad749a4SDag-Erling Smørgrav 	childerr = 0;
5638ad749a4SDag-Erling Smørgrav 	switch (pid = vfork()) {
5649b50d902SRodney W. Grimes 	case -1:
56570945890SJilles Tjoelker 		warn("vfork");
56670945890SJilles Tjoelker 		xexit(*argv, 1);
5679b50d902SRodney W. Grimes 	case 0:
568cec1ba8cSMaxime Henrion 		if (oflag) {
5690792992cSMaxime Henrion 			if ((fd = open(_PATH_TTY, O_RDONLY)) == -1)
5700792992cSMaxime Henrion 				err(1, "can't open /dev/tty");
571cec1ba8cSMaxime Henrion 		} else {
5720792992cSMaxime Henrion 			fd = open(_PATH_DEVNULL, O_RDONLY);
5730792992cSMaxime Henrion 		}
5740792992cSMaxime Henrion 		if (fd > STDIN_FILENO) {
5750792992cSMaxime Henrion 			if (dup2(fd, STDIN_FILENO) != 0)
5760792992cSMaxime Henrion 				err(1, "can't dup2 to stdin");
5770792992cSMaxime Henrion 			close(fd);
57898186e89SMaxime Henrion 		}
5799b50d902SRodney W. Grimes 		execvp(argv[0], argv);
5808ad749a4SDag-Erling Smørgrav 		childerr = errno;
5819b50d902SRodney W. Grimes 		_exit(1);
5829b50d902SRodney W. Grimes 	}
58392095ab6SStephen McKay 	pids_add(pid);
584330d23f5STim J. Robbins 	waitchildren(*argv, 0);
585330d23f5STim J. Robbins }
586330d23f5STim J. Robbins 
58792095ab6SStephen McKay /*
58892095ab6SStephen McKay  * Wait for a tracked child to exit and return its pid and exit status.
58992095ab6SStephen McKay  *
59092095ab6SStephen McKay  * Ignores (discards) all untracked child processes.
59192095ab6SStephen McKay  * Returns -1 and sets errno to ECHILD if no tracked children exist.
59292095ab6SStephen McKay  * If block is set, waits indefinitely for a child process to exit.
59392095ab6SStephen McKay  * If block is not set and no children have exited, returns 0 immediately.
59492095ab6SStephen McKay  */
59592095ab6SStephen McKay static pid_t
59692095ab6SStephen McKay xwait(int block, int *status) {
59792095ab6SStephen McKay 	pid_t pid;
59892095ab6SStephen McKay 
59992095ab6SStephen McKay 	if (pids_empty()) {
60092095ab6SStephen McKay 		errno = ECHILD;
60129afe03fSStephen McKay 		return (-1);
60292095ab6SStephen McKay 	}
60392095ab6SStephen McKay 
60492095ab6SStephen McKay 	while ((pid = waitpid(-1, status, block ? 0 : WNOHANG)) > 0)
60592095ab6SStephen McKay 		if (pids_remove(pid))
60692095ab6SStephen McKay 			break;
60792095ab6SStephen McKay 
60829afe03fSStephen McKay 	return (pid);
60992095ab6SStephen McKay }
61092095ab6SStephen McKay 
611330d23f5STim J. Robbins static void
61270945890SJilles Tjoelker xexit(const char *name, const int exit_code) {
61370945890SJilles Tjoelker 	waitchildren(name, 1);
61470945890SJilles Tjoelker 	exit(exit_code);
61570945890SJilles Tjoelker }
61670945890SJilles Tjoelker 
61770945890SJilles Tjoelker static void
618330d23f5STim J. Robbins waitchildren(const char *name, int waitall)
619330d23f5STim J. Robbins {
620330d23f5STim J. Robbins 	pid_t pid;
621330d23f5STim J. Robbins 	int status;
62270945890SJilles Tjoelker 	int cause_exit = 0;
623330d23f5STim J. Robbins 
62492095ab6SStephen McKay 	while ((pid = xwait(waitall || pids_full(), &status)) > 0) {
62570945890SJilles Tjoelker 		/*
62670945890SJilles Tjoelker 		 * If we couldn't invoke the utility or if utility exited
62770945890SJilles Tjoelker 		 * because of a signal or with a value of 255, warn (per
62870945890SJilles Tjoelker 		 * POSIX), and then wait until all other children have
62970945890SJilles Tjoelker 		 * exited before exiting 1-125. POSIX requires us to stop
63070945890SJilles Tjoelker 		 * reading if child exits because of a signal or with 255,
63170945890SJilles Tjoelker 		 * but it does not require us to exit immediately; waiting
63270945890SJilles Tjoelker 		 * is preferable to orphaning.
63370945890SJilles Tjoelker 		 */
63470945890SJilles Tjoelker 		if (childerr != 0 && cause_exit == 0) {
635330d23f5STim J. Robbins 			errno = childerr;
63670945890SJilles Tjoelker 			waitall = 1;
63770945890SJilles Tjoelker 			cause_exit = ENOENT ? 127 : 126;
63870945890SJilles Tjoelker 			warn("%s", name);
63970945890SJilles Tjoelker 		} else if (WIFSIGNALED(status)) {
64070945890SJilles Tjoelker 			waitall = cause_exit = 1;
64170945890SJilles Tjoelker 			warnx("%s: terminated with signal %d; aborting",
64223583c4fSJilles Tjoelker 			    name, WTERMSIG(status));
64370945890SJilles Tjoelker 		} else if (WEXITSTATUS(status) == 255) {
64470945890SJilles Tjoelker 			waitall = cause_exit = 1;
64570945890SJilles Tjoelker 			warnx("%s: exited with status 255; aborting", name);
64670945890SJilles Tjoelker 		} else if (WEXITSTATUS(status))
6479b50d902SRodney W. Grimes  			rval = 1;
6489b50d902SRodney W. Grimes 	}
64992095ab6SStephen McKay 
65070945890SJilles Tjoelker  	if (cause_exit)
65170945890SJilles Tjoelker 		exit(cause_exit);
652330d23f5STim J. Robbins 	if (pid == -1 && errno != ECHILD)
65392095ab6SStephen McKay 		err(1, "waitpid");
65492095ab6SStephen McKay }
65592095ab6SStephen McKay 
65692095ab6SStephen McKay #define	NOPID	(0)
65792095ab6SStephen McKay 
65892095ab6SStephen McKay static void
65929afe03fSStephen McKay pids_init(void)
66092095ab6SStephen McKay {
66192095ab6SStephen McKay 	int i;
66292095ab6SStephen McKay 
66392095ab6SStephen McKay 	if ((childpids = malloc(maxprocs * sizeof(*childpids))) == NULL)
66492095ab6SStephen McKay 		errx(1, "malloc failed");
66592095ab6SStephen McKay 
66692095ab6SStephen McKay 	for (i = 0; i < maxprocs; i++)
66792095ab6SStephen McKay 		clearslot(i);
66892095ab6SStephen McKay }
66992095ab6SStephen McKay 
67092095ab6SStephen McKay static int
67129afe03fSStephen McKay pids_empty(void)
67292095ab6SStephen McKay {
673*a274be77SEitan Adler 
67429afe03fSStephen McKay 	return (curprocs == 0);
67592095ab6SStephen McKay }
67692095ab6SStephen McKay 
67792095ab6SStephen McKay static int
67829afe03fSStephen McKay pids_full(void)
67992095ab6SStephen McKay {
680*a274be77SEitan Adler 
68129afe03fSStephen McKay 	return (curprocs >= maxprocs);
68292095ab6SStephen McKay }
68392095ab6SStephen McKay 
68492095ab6SStephen McKay static void
68592095ab6SStephen McKay pids_add(pid_t pid)
68692095ab6SStephen McKay {
68792095ab6SStephen McKay 	int slot;
68892095ab6SStephen McKay 
68992095ab6SStephen McKay 	slot = findfreeslot();
69092095ab6SStephen McKay 	childpids[slot] = pid;
69192095ab6SStephen McKay 	curprocs++;
69292095ab6SStephen McKay }
69392095ab6SStephen McKay 
69492095ab6SStephen McKay static int
69592095ab6SStephen McKay pids_remove(pid_t pid)
69692095ab6SStephen McKay {
69792095ab6SStephen McKay 	int slot;
69892095ab6SStephen McKay 
69992095ab6SStephen McKay 	if ((slot = findslot(pid)) < 0)
70029afe03fSStephen McKay 		return (0);
70192095ab6SStephen McKay 
70292095ab6SStephen McKay 	clearslot(slot);
70392095ab6SStephen McKay 	curprocs--;
70429afe03fSStephen McKay 	return (1);
70592095ab6SStephen McKay }
70692095ab6SStephen McKay 
70792095ab6SStephen McKay static int
70829afe03fSStephen McKay findfreeslot(void)
70992095ab6SStephen McKay {
71092095ab6SStephen McKay 	int slot;
71192095ab6SStephen McKay 
71292095ab6SStephen McKay 	if ((slot = findslot(NOPID)) < 0)
71392095ab6SStephen McKay 		errx(1, "internal error: no free pid slot");
71429afe03fSStephen McKay 	return (slot);
71592095ab6SStephen McKay }
71692095ab6SStephen McKay 
71792095ab6SStephen McKay static int
71892095ab6SStephen McKay findslot(pid_t pid)
71992095ab6SStephen McKay {
72092095ab6SStephen McKay 	int slot;
72192095ab6SStephen McKay 
72292095ab6SStephen McKay 	for (slot = 0; slot < maxprocs; slot++)
72392095ab6SStephen McKay 		if (childpids[slot] == pid)
72429afe03fSStephen McKay 			return (slot);
72529afe03fSStephen McKay 	return (-1);
72692095ab6SStephen McKay }
72792095ab6SStephen McKay 
72892095ab6SStephen McKay static void
72992095ab6SStephen McKay clearslot(int slot)
73092095ab6SStephen McKay {
731*a274be77SEitan Adler 
73292095ab6SStephen McKay 	childpids[slot] = NOPID;
733330d23f5STim J. Robbins }
7349b50d902SRodney W. Grimes 
735305e39f4SJuli Mallett /*
736305e39f4SJuli Mallett  * Prompt the user about running a command.
737305e39f4SJuli Mallett  */
738305e39f4SJuli Mallett static int
739305e39f4SJuli Mallett prompt(void)
740305e39f4SJuli Mallett {
741305e39f4SJuli Mallett 	regex_t cre;
742305e39f4SJuli Mallett 	size_t rsize;
743305e39f4SJuli Mallett 	int match;
744305e39f4SJuli Mallett 	char *response;
745305e39f4SJuli Mallett 	FILE *ttyfp;
746305e39f4SJuli Mallett 
747305e39f4SJuli Mallett 	if ((ttyfp = fopen(_PATH_TTY, "r")) == NULL)
748305e39f4SJuli Mallett 		return (2);	/* Indicate that the TTY failed to open. */
749305e39f4SJuli Mallett 	(void)fprintf(stderr, "?...");
750305e39f4SJuli Mallett 	(void)fflush(stderr);
751305e39f4SJuli Mallett 	if ((response = fgetln(ttyfp, &rsize)) == NULL ||
75230aaff11SWarner Losh 	    regcomp(&cre, nl_langinfo(YESEXPR), REG_BASIC) != 0) {
753305e39f4SJuli Mallett 		(void)fclose(ttyfp);
754305e39f4SJuli Mallett 		return (0);
755305e39f4SJuli Mallett 	}
756b65bc267SJuli Mallett 	response[rsize - 1] = '\0';
757305e39f4SJuli Mallett 	match = regexec(&cre, response, 0, NULL, 0);
758305e39f4SJuli Mallett 	(void)fclose(ttyfp);
759305e39f4SJuli Mallett 	regfree(&cre);
760305e39f4SJuli Mallett 	return (match == 0);
761305e39f4SJuli Mallett }
762305e39f4SJuli Mallett 
763a51024e2SPhilippe Charnier static void
76473385ac6SJuli Mallett usage(void)
7659b50d902SRodney W. Grimes {
766*a274be77SEitan Adler 
7678d904f15SDima Dorfman 	fprintf(stderr,
768ba084f6aSJuli Mallett "usage: xargs [-0opt] [-E eofstr] [-I replstr [-R replacements] [-S replsize]]\n"
769ba084f6aSJuli Mallett "             [-J replstr] [-L number] [-n number [-x]] [-P maxprocs]\n"
770ba084f6aSJuli Mallett "             [-s size] [utility [argument ...]]\n");
7719b50d902SRodney W. Grimes 	exit(1);
7729b50d902SRodney W. Grimes }
773