shell_cmds/apply/apply.c

   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 #if 0
  38 #ifndef lint
  39 static char sccsid[] = "@(#)apply.c     8.4 (Berkeley) 4/4/94";
  40 #endif
  41 #endif
  42
  43 #include <sys/cdefs.h>
  44 __RCSID("$FreeBSD: src/usr.bin/apply/apply.c,v 1.22 2002/07/14 18:22:12 alfred Exp $");
  45
  46 #include <sys/types.h>
  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
  58 #include <libiosexec.h>
  59
  60 #define EXEC    "exec "
  61
  62 static int      exec_shell(const char *, char *, char *);
  63 static void     usage(void);
  64
  65 int
  66 main(int argc, char *argv[]) {
  67         int ch, debug, i, magic, n, nargs, offset, rval;
  68         size_t clen, cmdsize, l;
  69         char *c, *cmd, *name, *p, *q, *shell, *slashp, *tmpshell;
  70
  71         debug = 0;
  72         magic = '%';            /* Default magic char is `%'. */
  73         nargs = -1;
  74         while ((ch = getopt(argc, argv, "a:d0123456789")) != -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 '0': case '1': case '2': case '3': case '4':
  86                 case '5': case '6': case '7': case '8': case '9':
  87                         if (nargs != -1)
  88                                 errx(1,
  89                                     "only one -# argument may be specified");
  90                         nargs = optopt - '0';
  91                         break;
  92                 default:
  93                         usage();
  94                 }
  95         argc -= optind;
  96         argv += optind;
  97
  98         if (argc < 2)
  99                 usage();
 100
 101         /*
 102          * The command to run is argv[0], and the args are argv[1..].
 103          * Look for %digit references in the command, remembering the
 104          * largest one.
 105          */
 106         for (n = 0, p = argv[0]; *p != '\0'; ++p)
 107                 if (p[0] == magic && isdigit(p[1]) && p[1] != '0') {
 108                         ++p;
 109                         if (p[0] - '0' > n)
 110                                 n = p[0] - '0';
 111                 }
 112
 113         /*
 114          * Figure out the shell and name arguments to pass to execl()
 115          * in exec_shell().  Always malloc() shell and just set name
 116          * to point at the last part of shell if there are any backslashes,
 117          * otherwise just set it to point at the space malloc()'d.  If
 118          * SHELL environment variable exists, replace contents of
 119          * shell with it.
 120          */
 121         shell = name = NULL;
 122         tmpshell = getenv("SHELL");
 123         shell = (tmpshell != NULL) ? strdup(tmpshell) : strdup(_PATH_BSHELL);
 124         if (shell == NULL)
 125                 err(1, "strdup() failed");
 126         slashp = strrchr(shell, '/');
 127         name = (slashp != NULL) ? slashp + 1 : shell;
 128
 129         /*
 130          * If there were any %digit references, then use those, otherwise
 131          * build a new command string with sufficient %digit references at
 132          * the end to consume (nargs) arguments each time round the loop.
 133          * Allocate enough space to hold the maximum command.  Save the
 134          * size to pass to snprintf().
 135          */
 136         cmdsize = sizeof(EXEC) - 1 + strlen(argv[0])
 137             + 9 * (sizeof(" %1") - 1) + 1;
 138         if ((cmd = malloc(cmdsize)) == NULL)
 139                 err(1, NULL);
 140
 141         if (n == 0) {
 142                 /* If nargs not set, default to a single argument. */
 143                 if (nargs == -1)
 144                         nargs = 1;
 145
 146                 p = cmd;
 147                 offset = snprintf(cmd, cmdsize, EXEC "%s", argv[0]);
 148                 if ((size_t)offset >= cmdsize)
 149                         err(1, "snprintf() failed");
 150                 p += offset;
 151                 cmdsize -= offset;
 152                 for (i = 1; i <= nargs; i++) {
 153                         offset = snprintf(p, cmdsize, " %c%d", magic, i);
 154                         if ((size_t)offset >= cmdsize)
 155                                 err(1, "snprintf() failed");
 156                         p += offset;
 157                         cmdsize -= offset;
 158                 }
 159
 160                 /*
 161                  * If nargs set to the special value 0, eat a single
 162                  * argument for each command execution.
 163                  */
 164                 if (nargs == 0)
 165                         nargs = 1;
 166         } else {
 167                 offset = snprintf(cmd, cmdsize, EXEC "%s", argv[0]);
 168                 if ((size_t)offset >= cmdsize)
 169                         err(1, "snprintf() failed");
 170                 nargs = n;
 171         }
 172
 173         /*
 174          * Grab some space in which to build the command.  Allocate
 175          * as necessary later, but no reason to build it up slowly
 176          * for the normal case.
 177          */
 178         if ((c = malloc(clen = 1024)) == NULL)
 179                 err(1, NULL);
 180
 181         /*
 182          * (argc) and (argv) are still offset by one to make it simpler to
 183          * expand %digit references.  At the end of the loop check for (argc)
 184          * equals 1 means that all the (argv) has been consumed.
 185          */
 186         for (rval = 0; argc > nargs; argc -= nargs, argv += nargs) {
 187                 /*
 188                  * Find a max value for the command length, and ensure
 189                  * there's enough space to build it.
 190                  */
 191                 for (l = strlen(cmd), i = 0; i < nargs; i++)
 192                         l += strlen(argv[i+1]);
 193                 if (l > clen && (c = realloc(c, clen = l)) == NULL)
 194                         err(1, NULL);
 195
 196                 /* Expand command argv references. */
 197                 for (p = cmd, q = c; *p != '\0'; ++p)
 198                         if (p[0] == magic && isdigit(p[1]) && p[1] != '0') {
 199                                 offset = snprintf(q, l, "%s",
 200                                     argv[(++p)[0] - '0']);
 201                                 if ((size_t)offset >= l)
 202                                         err(1, "snprintf() failed");
 203                                 q += offset;
 204                                 l -= offset;
 205                         } else
 206                                 *q++ = *p;
 207
 208                 /* Terminate the command string. */
 209                 *q = '\0';
 210
 211                 /* Run the command. */
 212                 if (debug)
 213                         (void)printf("%s\n", c);
 214                 else
 215                         if (exec_shell(c, shell, name))
 216                                 rval = 1;
 217         }
 218
 219         if (argc != 1)
 220                 errx(1, "expecting additional argument%s after \"%s\"",
 221             (nargs - argc) ? "s" : "", argv[argc - 1]);
 222         free(cmd);
 223         free(c);
 224         free(shell);
 225         exit(rval);
 226 }
 227
 228 /*
 229  * exec_shell --
 230  *      Execute a shell command using passed use_shell and use_name
 231  *      arguments.
 232  */
 233 static int
 234 exec_shell(const char *command, char *use_shell, char *use_name)
 235 {
 236         pid_t pid;
 237         int omask, pstat;
 238         sig_t intsave, quitsave;
 239
 240         if (!command)           /* just checking... */
 241                 return(1);
 242
 243         omask = sigblock(sigmask(SIGCHLD));
 244         switch(pid = vfork()) {
 245         case -1:                        /* error */
 246                 err(1, "vfork");
 247         case 0:                         /* child */
 248                 (void)sigsetmask(omask);
 249                 execl(use_shell, use_name, "-c", command, (char *)NULL);
 250                 warn("%s", use_shell);
 251                 _exit(1);
 252         }
 253         intsave = signal(SIGINT, SIG_IGN);
 254         quitsave = signal(SIGQUIT, SIG_IGN);
 255         pid = waitpid(pid, &pstat, 0);
 256         (void)sigsetmask(omask);
 257         (void)signal(SIGINT, intsave);
 258         (void)signal(SIGQUIT, quitsave);
 259         return(pid == -1 ? -1 : pstat);
 260 }
 261
 262 void
 263 usage(void)
 264 {
 265
 266         (void)fprintf(stderr,
 267         "usage: apply [-a magic] [-d] [-0123456789] command arguments ...\n");
 268         exit(1);
 269 }