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 "$FreeBSD$"; 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, jfound, indouble, insingle; 74 int nargs, nflag, nline, xflag, wasquoted; 75 char **av, **avj, *argp, **ep, *replstr; 76 long arg_max; 77 78 ep = env; 79 jfound = 0; 80 replstr = NULL; /* set if user requests -J */ 81 82 /* 83 * POSIX.2 limits the exec line length to ARG_MAX - 2K. Running that 84 * caused some E2BIG errors, so it was changed to ARG_MAX - 4K. Given 85 * that the smallest argument is 2 bytes in length, this means that 86 * the number of arguments is limited to: 87 * 88 * (ARG_MAX - 4K - LENGTH(utility + arguments)) / 2. 89 * 90 * We arbitrarily limit the number of arguments to 5000. This is 91 * allowed by POSIX.2 as long as the resulting minimum exec line is 92 * at least LINE_MAX. Realloc'ing as necessary is possible, but 93 * probably not worthwhile. 94 */ 95 nargs = 5000; 96 if ((arg_max = sysconf(_SC_ARG_MAX)) == -1) 97 errx(1, "sysconf(_SC_ARG_MAX) failed"); 98 nline = arg_max - 4 * 1024; 99 while (*ep) { 100 /* 1 byte for each '\0' */ 101 nline -= strlen(*ep++) + 1 + sizeof(*ep); 102 } 103 nflag = xflag = wasquoted = 0; 104 while ((ch = getopt(argc, argv, "0J:n:s:tx")) != -1) 105 switch(ch) { 106 case 'J': 107 replstr = optarg; 108 break; 109 case 'n': 110 nflag = 1; 111 if ((nargs = atoi(optarg)) <= 0) 112 errx(1, "illegal argument count"); 113 break; 114 case 's': 115 nline = atoi(optarg); 116 break; 117 case 't': 118 tflag = 1; 119 break; 120 case 'x': 121 xflag = 1; 122 break; 123 case '0': 124 zflag = 1; 125 break; 126 case '?': 127 default: 128 usage(); 129 } 130 argc -= optind; 131 argv += optind; 132 133 if (xflag && !nflag) 134 usage(); 135 136 /* 137 * Allocate pointers for the utility name, the utility arguments, 138 * the maximum arguments to be read from stdin and the trailing 139 * NULL. 140 */ 141 if (!(av = bxp = 142 malloc((u_int)(1 + argc + nargs + 1) * sizeof(char **)))) 143 errx(1, "malloc"); 144 145 /* 146 * Use the user's name for the utility as argv[0], just like the 147 * shell. Echo is the default. Set up pointers for the user's 148 * arguments. 149 */ 150 if (!*argv) 151 cnt = strlen(*bxp++ = _PATH_ECHO); 152 else { 153 cnt = 0; 154 do { 155 if (replstr && strcmp(*argv, replstr) == 0) { 156 jfound = 1; 157 argv++; 158 for (avj = argv; *avj; avj++) 159 cnt += strlen(*avj) + 1; 160 break; 161 } 162 cnt += strlen(*bxp++ = *argv) + 1; 163 } while (*++argv); 164 } 165 166 /* 167 * Set up begin/end/traversing pointers into the array. The -n 168 * count doesn't include the trailing NULL pointer, so the malloc 169 * added in an extra slot. 170 */ 171 exp = (xp = bxp) + nargs; 172 173 /* 174 * Allocate buffer space for the arguments read from stdin and the 175 * trailing NULL. Buffer space is defined as the default or specified 176 * space, minus the length of the utility name and arguments. Set up 177 * begin/end/traversing pointers into the array. The -s count does 178 * include the trailing NULL, so the malloc didn't add in an extra 179 * slot. 180 */ 181 nline -= cnt; 182 if (nline <= 0) 183 errx(1, "insufficient space for command"); 184 185 if (!(bbp = malloc((u_int)nline + 1))) 186 errx(1, "malloc"); 187 ebp = (argp = p = bbp) + nline - 1; 188 189 for (insingle = indouble = 0;;) 190 switch(ch = getchar()) { 191 case EOF: 192 /* No arguments since last exec. */ 193 if (p == bbp) 194 exit(rval); 195 goto arg1; 196 case ' ': 197 case '\t': 198 /* Quotes escape tabs and spaces. */ 199 if (insingle || indouble || zflag) 200 goto addch; 201 goto arg2; 202 case '\0': 203 if (zflag) 204 goto arg2; 205 goto addch; 206 case '\n': 207 if (zflag) 208 goto addch; 209 210 /* Quotes do not escape newlines. */ 211 arg1: if (insingle || indouble) 212 errx(1, "unterminated quote"); 213 214 arg2: 215 /* Do not make empty args unless they are quoted */ 216 if (argp != p || wasquoted) { 217 *p++ = '\0'; 218 *xp++ = argp; 219 } 220 221 /* 222 * If max'd out on args or buffer, or reached EOF, 223 * run the command. If xflag and max'd out on buffer 224 * but not on args, object. 225 */ 226 if (xp == exp || p > ebp || ch == EOF) { 227 if (xflag && xp != exp && p > ebp) 228 errx(1, "insufficient space for arguments"); 229 if (jfound) { 230 for (avj = argv; *avj; avj++) 231 *xp++ = *avj; 232 } 233 *xp = NULL; 234 run(av); 235 if (ch == EOF) 236 exit(rval); 237 p = bbp; 238 xp = bxp; 239 } 240 argp = p; 241 wasquoted = 0; 242 break; 243 case '\'': 244 if (indouble || zflag) 245 goto addch; 246 insingle = !insingle; 247 wasquoted = 1; 248 break; 249 case '"': 250 if (insingle || zflag) 251 goto addch; 252 indouble = !indouble; 253 wasquoted = 1; 254 break; 255 case '\\': 256 if (zflag) 257 goto addch; 258 /* Backslash escapes anything, is escaped by quotes. */ 259 if (!insingle && !indouble && (ch = getchar()) == EOF) 260 errx(1, "backslash at EOF"); 261 /* FALLTHROUGH */ 262 default: 263 addch: if (p < ebp) { 264 *p++ = ch; 265 break; 266 } 267 268 /* If only one argument, not enough buffer space. */ 269 if (bxp == xp) 270 errx(1, "insufficient space for argument"); 271 /* Didn't hit argument limit, so if xflag object. */ 272 if (xflag) 273 errx(1, "insufficient space for arguments"); 274 275 if (jfound) { 276 for (avj = argv; *avj; avj++) 277 *xp++ = *avj; 278 } 279 *xp = NULL; 280 run(av); 281 xp = bxp; 282 cnt = ebp - argp; 283 bcopy(argp, bbp, cnt); 284 p = (argp = bbp) + cnt; 285 *p++ = ch; 286 break; 287 } 288 /* NOTREACHED */ 289 } 290 291 void 292 run(argv) 293 char **argv; 294 { 295 volatile int noinvoke; 296 register char **p; 297 pid_t pid; 298 int status; 299 300 if (tflag) { 301 (void)fprintf(stderr, "%s", *argv); 302 for (p = argv + 1; *p; ++p) 303 (void)fprintf(stderr, " %s", *p); 304 (void)fprintf(stderr, "\n"); 305 (void)fflush(stderr); 306 } 307 noinvoke = 0; 308 switch(pid = fork()) { 309 case -1: 310 err(1, "fork"); 311 case 0: 312 execvp(argv[0], argv); 313 warn("%s", argv[0]); 314 noinvoke = 1; 315 _exit(1); 316 } 317 pid = waitpid(pid, &status, 0); 318 if (pid == -1) 319 err(1, "waitpid"); 320 /* If we couldn't invoke the utility, exit 127. */ 321 if (noinvoke) 322 exit(127); 323 /* If utility signaled or exited with a value of 255, exit 1-125. */ 324 if (WIFSIGNALED(status) || WEXITSTATUS(status) == 255) 325 exit(1); 326 if (WEXITSTATUS(status)) 327 rval = 1; 328 } 329 330 static void 331 usage() 332 { 333 fprintf(stderr, 334 "usage: xargs [-0t] [-J replstr] [-n number [-x]] [-s size]\n" 335 " [utility [argument ...]]\n"); 336 exit(1); 337 } 338