/* $OpenBSD: xargs.c,v 1.13 2003/06/10 22:20:54 deraadt Exp $ */ /* $NetBSD: xargs.c,v 1.7 1994/11/14 06:51:41 jtc Exp $ */ /*- * Copyright (c) 1990, 1993 * The Regents of the University of California. All rights reserved. * * This code is derived from software contributed to Berkeley by * John B. Roll Jr. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * 3. Neither the name of the University nor the names of its contributors * may be used to endorse or promote products derived from this software * without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. */ #ifndef lint static char copyright[] = "@(#) Copyright (c) 1990, 1993\n\ The Regents of the University of California. All rights reserved.\n"; #endif /* not lint */ #ifndef lint #if 0 static char sccsid[] = "@(#)xargs.c 8.1 (Berkeley) 6/6/93"; #endif static char rcsid[] = "$OpenBSD: xargs.c,v 1.13 2003/06/10 22:20:54 deraadt Exp $"; #endif /* not lint */ #include #include #include #include #include #include #include #include #include #include #include #include "pathnames.h" int tflag, rval; int zflag; void run(char **); void usage(void); int main(int argc, char *argv[]) { int ch; char *p, *bbp, *ebp, **bxp, **exp, **xp; int cnt, indouble, insingle, nargs, nflag, nline, xflag; char **av, *argp; int arg_max; setlocale(LC_ALL, ""); /* * POSIX.2 limits the exec line length to ARG_MAX - 2K. Running that * caused some E2BIG errors, so it was changed to ARG_MAX - 4K. Given * that the smallest argument is 2 bytes in length, this means that * the number of arguments is limited to: * * (ARG_MAX - 4K - LENGTH(utility + arguments)) / 2. * * We arbitrarily limit the number of arguments to 5000. This is * allowed by POSIX.2 as long as the resulting minimum exec line is * at least LINE_MAX. Realloc'ing as necessary is possible, but * probably not worthwhile. */ nargs = 5000; if ((arg_max = sysconf(_SC_ARG_MAX)) == -1) errx(1, "sysconf(_SC_ARG_MAX) failed"); nline = arg_max - 4 * 1024; nflag = xflag = 0; while ((ch = getopt(argc, argv, "0n:s:tx")) != -1) switch(ch) { case 'n': nflag = 1; if ((nargs = atoi(optarg)) <= 0) errx(1, "illegal argument count"); break; case 's': nline = atoi(optarg); break; case 't': tflag = 1; break; case 'x': xflag = 1; break; case '0': zflag = 1; break; case '?': default: usage(); } argc -= optind; argv += optind; /* * Allocate pointers for the utility name, the utility arguments, * the maximum arguments to be read from stdin and the trailing * NULL. */ if (!(av = bxp = malloc((u_int)(1 + argc + nargs + 1) * sizeof(char **)))) err(1, NULL); /* * Use the user's name for the utility as argv[0], just like the * shell. Echo is the default. Set up pointers for the user's * arguments. */ if (!*argv) cnt = strlen(*bxp++ = _PATH_ECHO); else { cnt = 0; do { cnt += strlen(*bxp++ = *argv) + 1; } while (*++argv); } /* * Set up begin/end/traversing pointers into the array. The -n * count doesn't include the trailing NULL pointer, so the malloc * added in an extra slot. */ exp = (xp = bxp) + nargs; /* * Allocate buffer space for the arguments read from stdin and the * trailing NULL. Buffer space is defined as the default or specified * space, minus the length of the utility name and arguments. Set up * begin/end/traversing pointers into the array. The -s count does * include the trailing NULL, so the malloc didn't add in an extra * slot. */ nline -= cnt; if (nline <= 0) errx(1, "insufficient space for command"); if (!(bbp = malloc((u_int)nline + 1))) err(1, NULL); ebp = (argp = p = bbp) + nline - 1; for (insingle = indouble = 0;;) switch(ch = getchar()) { case EOF: /* No arguments since last exec. */ if (p == bbp) exit(rval); /* Nothing since end of last argument. */ if (argp == p) { *xp = NULL; run(av); exit(rval); } goto arg1; case ' ': case '\t': /* Quotes escape tabs and spaces. */ if (insingle || indouble || zflag) goto addch; goto arg2; case '\0': if (zflag) goto arg2; goto addch; case '\n': if (zflag) goto addch; /* Empty lines are skipped. */ if (argp == p) continue; /* Quotes do not escape newlines. */ arg1: if (insingle || indouble) errx(1, "unterminated quote"); arg2: *p = '\0'; *xp++ = argp; /* * If max'd out on args or buffer, or reached EOF, * run the command. If xflag and max'd out on buffer * but not on args, object. */ if (xp == exp || p == ebp || ch == EOF) { if (xflag && xp != exp && p == ebp) errx(1, "insufficient space for arguments"); *xp = NULL; run(av); if (ch == EOF) exit(rval); p = bbp; xp = bxp; } else ++p; argp = p; break; case '\'': if (indouble || zflag) goto addch; insingle = !insingle; break; case '"': if (insingle || zflag) goto addch; indouble = !indouble; break; case '\\': if (zflag) goto addch; /* Backslash escapes anything, is escaped by quotes. */ if (!insingle && !indouble && (ch = getchar()) == EOF) errx(1, "backslash at EOF"); /* FALLTHROUGH */ default: addch: if (p < ebp) { *p++ = ch; break; } /* If only one argument, not enough buffer space. */ if (bxp == xp) errx(1, "insufficient space for argument"); /* Didn't hit argument limit, so if xflag object. */ if (xflag) errx(1, "insufficient space for arguments"); *xp = NULL; run(av); xp = bxp; cnt = ebp - argp; bcopy(argp, bbp, cnt); p = (argp = bbp) + cnt; *p++ = ch; break; } /* NOTREACHED */ } void run(char **argv) { volatile int noinvoke; char **p; pid_t pid; int status; if (tflag) { (void)fprintf(stderr, "%s", *argv); for (p = argv + 1; *p; ++p) (void)fprintf(stderr, " %s", *p); (void)fprintf(stderr, "\n"); (void)fflush(stderr); } noinvoke = 0; switch(pid = vfork()) { case -1: err(1, "vfork"); case 0: execvp(argv[0], argv); noinvoke = (errno == ENOENT) ? 127 : 126; warn("%s", argv[0]); _exit(1); } pid = waitpid(pid, &status, 0); if (pid == -1) err(1, "waitpid"); /* * If we couldn't invoke the utility or the utility didn't exit * properly, quit with 127 or 126 respectively. */ if (noinvoke) exit(noinvoke); /* * According to POSIX, we have to exit if the utility exits with * a 255 status, or is interrupted by a signal. xargs is allowed * to return any exit status between 1 and 125 in these cases, but * we'll use 124 and 125, the same values used by GNU xargs. */ if (WIFEXITED(status)) { if (WEXITSTATUS(status) == 255) { warnx("%s exited with status 255", argv[0]); exit(124); } else if (WEXITSTATUS(status) != 0) { rval = 123; } } else if (WIFSIGNALED(status)) { if (WTERMSIG(status) != SIGPIPE) { if (WTERMSIG(status) < NSIG) warnx("%s terminated by SIG%s", argv[0], sys_signame[WTERMSIG(status)]); else warnx("%s terminated by signal %d", argv[0], WTERMSIG(status)); } exit(125); } } void usage(void) { fprintf(stderr, "usage: xargs [-0] [-t] [-n number [-x]] [-s size] " "[utility [argument ...]]\n"); exit(1); }