apply.c revision 70669
1/*- 2 * Copyright (c) 1994 3 * The Regents of the University of California. All rights reserved. 4 * 5 * This code is derived from software contributed to Berkeley by 6 * Jan-Simon Pendry. 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#if 0 39static const char sccsid[] = "@(#)apply.c 8.4 (Berkeley) 4/4/94"; 40#endif 41static const char rcsid[] = 42 "$FreeBSD: head/usr.bin/apply/apply.c 70669 2001-01-04 19:05:49Z will $"; 43#endif /* not lint */ 44 45#include <sys/types.h> 46 47#include <sys/wait.h> 48 49#include <ctype.h> 50#include <err.h> 51#include <paths.h> 52#include <signal.h> 53#include <stdio.h> 54#include <stdlib.h> 55#include <string.h> 56#include <unistd.h> 57 58void usage (void); 59static int exec_shell (const char *); 60 61static unsigned int prespecified; 62static char *shell; 63 64int 65main(int argc, char **argv) 66{ 67 int ch, debug, i, magic, n, nargs, rval; 68 size_t clen, l; 69 char *c, *cmd, *p, *q; 70 71 debug = 0; 72 magic = '%'; /* Default magic char is `%'. */ 73 nargs = -1; 74 while ((ch = getopt(argc, argv, "a:ds:0123456789")) != -1) 75 switch (ch) { 76 case 'a': 77 if (optarg[1] != '\0') 78 errx(1, 79 "illegal magic character specification"); 80 magic = optarg[0]; 81 break; 82 case 'd': 83 debug = 1; 84 break; 85 case 's': 86 prespecified = 1; 87 shell = optarg; 88 break; 89 case '0': case '1': case '2': case '3': case '4': 90 case '5': case '6': case '7': case '8': case '9': 91 if (nargs != -1) 92 errx(1, 93 "only one -# argument may be specified"); 94 nargs = optopt - '0'; 95 break; 96 default: 97 usage(); 98 } 99 argc -= optind; 100 argv += optind; 101 102 if (argc < 2) 103 usage(); 104 105 /* 106 * The command to run is argv[0], and the args are argv[1..]. 107 * Look for %digit references in the command, remembering the 108 * largest one. 109 */ 110 for (n = 0, p = argv[0]; *p != '\0'; ++p) 111 if (p[0] == magic && isdigit(p[1]) && p[1] != '0') { 112 ++p; 113 if (p[0] - '0' > n) 114 n = p[0] - '0'; 115 } 116 117 /* 118 * If there were any %digit references, then use those, otherwise 119 * build a new command string with sufficient %digit references at 120 * the end to consume (nargs) arguments each time round the loop. 121 * Allocate enough space to hold the maximum command. 122 */ 123 if ((cmd = malloc(sizeof("exec ") - 1 + 124 strlen(argv[0]) + 9 * (sizeof(" %1") - 1) + 1)) == NULL) 125 err(1, NULL); 126 127 if (n == 0) { 128 /* If nargs not set, default to a single argument. */ 129 if (nargs == -1) 130 nargs = 1; 131 132 p = cmd; 133 p += snprintf(cmd, sizeof(cmd), "exec %s", argv[0]); 134 for (i = 1; i <= nargs; i++) 135 p += snprintf(p, sizeof(p), " %c%d", magic, i); 136 137 /* 138 * If nargs set to the special value 0, eat a single 139 * argument for each command execution. 140 */ 141 if (nargs == 0) 142 nargs = 1; 143 } else { 144 (void)snprintf(cmd, sizeof(cmd), "exec %s", argv[0]); 145 nargs = n; 146 } 147 148 /* 149 * Grab some space in which to build the command. Allocate 150 * as necessary later, but no reason to build it up slowly 151 * for the normal case. 152 */ 153 if ((c = malloc(clen = 1024)) == NULL) 154 err(1, NULL); 155 156 /* 157 * (argc) and (argv) are still offset by one to make it simpler to 158 * expand %digit references. At the end of the loop check for (argc) 159 * equals 1 means that all the (argv) has been consumed. 160 */ 161 for (rval = 0; argc > nargs; argc -= nargs, argv += nargs) { 162 /* 163 * Find a max value for the command length, and ensure 164 * there's enough space to build it. 165 */ 166 for (l = strlen(cmd), i = 0; i < nargs; i++) 167 l += strlen(argv[i+1]); 168 if (l > clen && (c = realloc(c, clen = l)) == NULL) 169 err(1, NULL); 170 171 /* Expand command argv references. */ 172 for (p = cmd, q = c; *p != '\0'; ++p) 173 if (p[0] == magic && isdigit(p[1]) && p[1] != '0') 174 q += snprintf(q, sizeof(q), "%s", argv[(++p)[0] - '0']); 175 else 176 *q++ = *p; 177 178 /* Terminate the command string. */ 179 *q = '\0'; 180 181 /* Run the command. */ 182 if (debug) 183 (void)printf("%s\n", c); 184 else 185 if (exec_shell(c)) 186 rval = 1; 187 } 188 189 if (argc != 1) 190 errx(1, "expecting additional argument%s after \"%s\"", 191 (nargs - argc) ? "s" : "", argv[argc - 1]); 192 exit(rval); 193} 194 195/* 196 * exec_shell -- 197 * Private version of system(3). Use the user's SHELL environment 198 * variable as the shell to execute. 199 */ 200static int 201exec_shell(const char *command) 202{ 203 static char *name; 204 char *tmpshell; 205 pid_t pid; 206 int omask, pstat; 207 sig_t intsave, quitsave; 208 unsigned int okshell = 0; 209 210 if (shell == NULL) { 211 if ((shell = getenv("SHELL")) == NULL) 212 if (strlcpy(shell, _PATH_BSHELL, sizeof(shell)) != strlen(shell)) 213 err(1, "strlcpy() failed"); 214 if ((name = strrchr(shell, '/')) == NULL) { 215 if (strlcpy(name, shell, sizeof(name)) != strlen(shell)) 216 err(1, "strlcpy() failed"); 217 } else { 218 ++name; 219 } 220 } 221 222 /* Now double-check to make sure the shell is friendly */ 223 if (!prespecified) 224 while((tmpshell = getusershell()) != NULL) 225 if (strcmp((const char *)tmpshell, (const char *)shell) == 0) 226 okshell = 1; 227 228 if (!command || !okshell) /* just checking... */ 229 return(1); 230 231 omask = sigblock(sigmask(SIGCHLD)); 232 switch(pid = vfork()) { 233 case -1: /* error */ 234 err(1, "vfork"); 235 case 0: /* child */ 236 (void)sigsetmask(omask); 237 execl(shell, name, "-c", command, NULL); 238 warn("%s", shell); 239 _exit(1); 240 } 241 intsave = signal(SIGINT, SIG_IGN); 242 quitsave = signal(SIGQUIT, SIG_IGN); 243 pid = waitpid(pid, &pstat, 0); 244 (void)sigsetmask(omask); 245 (void)signal(SIGINT, intsave); 246 (void)signal(SIGQUIT, quitsave); 247 return(pid == -1 ? -1 : pstat); 248} 249 250void 251usage() 252{ 253 254 (void)fprintf(stderr, 255 "usage: apply [-a magic] [-d] [-s shell] [-0123456789] command arguments ...\n"); 256 exit(1); 257} 258