1 /*- 2 * Copyright (c) 1990, 1993 3 * The Regents of the University of California. All rights reserved. 4 * 5 * This code is derived from software contributed to Berkeley by 6 * John B. Roll Jr. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 1. Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in the 15 * documentation and/or other materials provided with the distribution. 16 * 3. All advertising materials mentioning features or use of this software 17 * must display the following acknowledgement: 18 * This product includes software developed by the University of 19 * California, Berkeley and its contributors. 20 * 4. Neither the name of the University nor the names of its contributors 21 * may be used to endorse or promote products derived from this software 22 * without specific prior written permission. 23 * 24 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 25 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 26 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 27 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 28 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 29 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 30 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 31 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 32 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 33 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 34 * SUCH DAMAGE. 35 */ 36 37 #ifndef lint 38 static const char copyright[] = 39 "@(#) Copyright (c) 1990, 1993\n\ 40 The Regents of the University of California. All rights reserved.\n"; 41 #endif /* not lint */ 42 43 #ifndef lint 44 #if 0 45 static char sccsid[] = "@(#)xargs.c 8.1 (Berkeley) 6/6/93"; 46 #endif 47 static const char rcsid[] = 48 "$Id: xargs.c,v 1.7 1998/10/13 14:52:32 des Exp $"; 49 #endif /* not lint */ 50 51 #include <sys/types.h> 52 #include <sys/wait.h> 53 #include <err.h> 54 #include <stdio.h> 55 #include <stdlib.h> 56 #include <string.h> 57 #include <unistd.h> 58 #include "pathnames.h" 59 60 int tflag, rval; 61 int zflag; 62 63 void run __P((char **)); 64 static void usage __P((void)); 65 66 int 67 main(argc, argv, env) 68 int argc; 69 char **argv, **env; 70 { 71 register int ch; 72 register char *p, *bbp, *ebp, **bxp, **exp, **xp; 73 int cnt, indouble, insingle, nargs, nflag, nline, xflag, wasquoted; 74 char **av, *argp, **ep = env; 75 long arg_max; 76 77 /* 78 * POSIX.2 limits the exec line length to ARG_MAX - 2K. Running that 79 * caused some E2BIG errors, so it was changed to ARG_MAX - 4K. Given 80 * that the smallest argument is 2 bytes in length, this means that 81 * the number of arguments is limited to: 82 * 83 * (ARG_MAX - 4K - LENGTH(utility + arguments)) / 2. 84 * 85 * We arbitrarily limit the number of arguments to 5000. This is 86 * allowed by POSIX.2 as long as the resulting minimum exec line is 87 * at least LINE_MAX. Realloc'ing as necessary is possible, but 88 * probably not worthwhile. 89 */ 90 nargs = 5000; 91 if ((arg_max = sysconf(_SC_ARG_MAX)) == -1) 92 errx(1, "sysconf(_SC_ARG_MAX) failed"); 93 nline = arg_max - 4 * 1024; 94 while (*ep) { 95 /* 1 byte for each '\0' */ 96 nline -= strlen(*ep++) + 1 + sizeof(*ep); 97 } 98 nflag = xflag = wasquoted = 0; 99 while ((ch = getopt(argc, argv, "0n:s:tx")) != -1) 100 switch(ch) { 101 case 'n': 102 nflag = 1; 103 if ((nargs = atoi(optarg)) <= 0) 104 errx(1, "illegal argument count"); 105 break; 106 case 's': 107 nline = atoi(optarg); 108 break; 109 case 't': 110 tflag = 1; 111 break; 112 case 'x': 113 xflag = 1; 114 break; 115 case '0': 116 zflag = 1; 117 break; 118 case '?': 119 default: 120 usage(); 121 } 122 argc -= optind; 123 argv += optind; 124 125 if (xflag && !nflag) 126 usage(); 127 128 /* 129 * Allocate pointers for the utility name, the utility arguments, 130 * the maximum arguments to be read from stdin and the trailing 131 * NULL. 132 */ 133 if (!(av = bxp = 134 malloc((u_int)(1 + argc + nargs + 1) * sizeof(char **)))) 135 errx(1, "malloc"); 136 137 /* 138 * Use the user's name for the utility as argv[0], just like the 139 * shell. Echo is the default. Set up pointers for the user's 140 * arguments. 141 */ 142 if (!*argv) 143 cnt = strlen(*bxp++ = _PATH_ECHO); 144 else { 145 cnt = 0; 146 do { 147 cnt += strlen(*bxp++ = *argv) + 1; 148 } while (*++argv); 149 } 150 151 /* 152 * Set up begin/end/traversing pointers into the array. The -n 153 * count doesn't include the trailing NULL pointer, so the malloc 154 * added in an extra slot. 155 */ 156 exp = (xp = bxp) + nargs; 157 158 /* 159 * Allocate buffer space for the arguments read from stdin and the 160 * trailing NULL. Buffer space is defined as the default or specified 161 * space, minus the length of the utility name and arguments. Set up 162 * begin/end/traversing pointers into the array. The -s count does 163 * include the trailing NULL, so the malloc didn't add in an extra 164 * slot. 165 */ 166 nline -= cnt; 167 if (nline <= 0) 168 errx(1, "insufficient space for command"); 169 170 if (!(bbp = malloc((u_int)nline + 1))) 171 errx(1, "malloc"); 172 ebp = (argp = p = bbp) + nline - 1; 173 174 for (insingle = indouble = 0;;) 175 switch(ch = getchar()) { 176 case EOF: 177 /* No arguments since last exec. */ 178 if (p == bbp) 179 exit(rval); 180 goto arg1; 181 case ' ': 182 case '\t': 183 /* Quotes escape tabs and spaces. */ 184 if (insingle || indouble || zflag) 185 goto addch; 186 goto arg2; 187 case '\0': 188 if (zflag) 189 goto arg2; 190 goto addch; 191 case '\n': 192 if (zflag) 193 goto addch; 194 195 /* Quotes do not escape newlines. */ 196 arg1: if (insingle || indouble) 197 errx(1, "unterminated quote"); 198 199 arg2: 200 /* Do not make empty args unless they are quoted */ 201 if (argp != p || wasquoted) { 202 *p++ = '\0'; 203 *xp++ = argp; 204 } 205 206 /* 207 * If max'd out on args or buffer, or reached EOF, 208 * run the command. If xflag and max'd out on buffer 209 * but not on args, object. 210 */ 211 if (xp == exp || p > ebp || ch == EOF) { 212 if (xflag && xp != exp && p > ebp) 213 errx(1, "insufficient space for arguments"); 214 *xp = NULL; 215 run(av); 216 if (ch == EOF) 217 exit(rval); 218 p = bbp; 219 xp = bxp; 220 } 221 argp = p; 222 wasquoted = 0; 223 break; 224 case '\'': 225 if (indouble || zflag) 226 goto addch; 227 insingle = !insingle; 228 wasquoted = 1; 229 break; 230 case '"': 231 if (insingle || zflag) 232 goto addch; 233 indouble = !indouble; 234 wasquoted = 1; 235 break; 236 case '\\': 237 if (zflag) 238 goto addch; 239 /* Backslash escapes anything, is escaped by quotes. */ 240 if (!insingle && !indouble && (ch = getchar()) == EOF) 241 errx(1, "backslash at EOF"); 242 /* FALLTHROUGH */ 243 default: 244 addch: if (p < ebp) { 245 *p++ = ch; 246 break; 247 } 248 249 /* If only one argument, not enough buffer space. */ 250 if (bxp == xp) 251 errx(1, "insufficient space for argument"); 252 /* Didn't hit argument limit, so if xflag object. */ 253 if (xflag) 254 errx(1, "insufficient space for arguments"); 255 256 *xp = NULL; 257 run(av); 258 xp = bxp; 259 cnt = ebp - argp; 260 bcopy(argp, bbp, cnt); 261 p = (argp = bbp) + cnt; 262 *p++ = ch; 263 break; 264 } 265 /* NOTREACHED */ 266 } 267 268 void 269 run(argv) 270 char **argv; 271 { 272 volatile int noinvoke; 273 register char **p; 274 pid_t pid; 275 int status; 276 277 if (tflag) { 278 (void)fprintf(stderr, "%s", *argv); 279 for (p = argv + 1; *p; ++p) 280 (void)fprintf(stderr, " %s", *p); 281 (void)fprintf(stderr, "\n"); 282 (void)fflush(stderr); 283 } 284 noinvoke = 0; 285 switch(pid = fork()) { 286 case -1: 287 err(1, "fork"); 288 case 0: 289 execvp(argv[0], argv); 290 warn("%s", argv[0]); 291 noinvoke = 1; 292 _exit(1); 293 } 294 pid = waitpid(pid, &status, 0); 295 if (pid == -1) 296 err(1, "waitpid"); 297 /* If we couldn't invoke the utility, exit 127. */ 298 if (noinvoke) 299 exit(127); 300 /* If utility signaled or exited with a value of 255, exit 1-125. */ 301 if (WIFSIGNALED(status) || WEXITSTATUS(status) == 255) 302 exit(1); 303 if (WEXITSTATUS(status)) 304 rval = 1; 305 } 306 307 static void 308 usage() 309 { 310 (void)fprintf(stderr, 311 "usage: xargs [-0] [-t] [-n number [-x]] [-s size] [utility [argument ...]]\n"); 312 exit(1); 313 } 314