usr.bin/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  * @(#)apply.c  8.4 (Berkeley) 4/4/94
  37  * $FreeBSD: src/usr.bin/apply/apply.c,v 1.8.2.3 2001/08/01 23:28:04 obrien Exp $
  38  * $DragonFly: src/usr.bin/apply/apply.c,v 1.5 2005/01/04 05:45:02 cpressey Exp $
  39  */
  40
  41 #include <sys/types.h>
  42
  43 #include <sys/wait.h>
  44
  45 #include <ctype.h>
  46 #include <err.h>
  47 #include <paths.h>
  48 #include <signal.h>
  49 #include <stdio.h>
  50 #include <stdlib.h>
  51 #include <string.h>
  52 #include <unistd.h>
  53
  54 #define EXEC    "exec "
  55
  56 static int      exec_shell(const char *, char *, char *);
  57 static void     usage(void);
  58
  59 int
  60 main(int argc, char *argv[])
  61 {
  62         int ch, debug, i, magic, n, nargs, offset, rval;
  63         size_t clen, cmdsize, l;
  64         char *c, *cmd, *name, *p, *q, *shell, *slashp, *tmpshell;
  65
  66         debug = 0;
  67         magic = '%';            /* Default magic char is `%'. */
  68         nargs = -1;
  69         while ((ch = getopt(argc, argv, "a:d0123456789")) != -1)
  70                 switch (ch) {
  71                 case 'a':
  72                         if (optarg[1] != '\0')
  73                                 errx(1,
  74                                     "illegal magic character specification");
  75                         magic = optarg[0];
  76                         break;
  77                 case 'd':
  78                         debug = 1;
  79                         break;
  80                 case '0': case '1': case '2': case '3': case '4':
  81                 case '5': case '6': case '7': case '8': case '9':
  82                         if (nargs != -1)
  83                                 errx(1,
  84                                     "only one -# argument may be specified");
  85                         nargs = optopt - '0';
  86                         break;
  87                 default:
  88                         usage();
  89                 }
  90         argc -= optind;
  91         argv += optind;
  92
  93         if (argc < 2)
  94                 usage();
  95
  96         /*
  97          * The command to run is argv[0], and the args are argv[1..].
  98          * Look for %digit references in the command, remembering the
  99          * largest one.
 100          */
 101         for (n = 0, p = argv[0]; *p != '\0'; ++p)
 102                 if (p[0] == magic && isdigit(p[1]) && p[1] != '0') {
 103                         ++p;
 104                         if (p[0] - '0' > n)
 105                                 n = p[0] - '0';
 106                 }
 107
 108         /*
 109          * Figure out the shell and name arguments to pass to execl()
 110          * in exec_shell().  Always malloc() shell and just set name
 111          * to point at the last part of shell if there are any backslashes,
 112          * otherwise just set it to point at the space malloc()'d.  If
 113          * SHELL environment variable exists, replace contents of
 114          * shell with it.
 115          */
 116         shell = name = NULL;
 117         tmpshell = getenv("SHELL");
 118         shell = (tmpshell != NULL) ? strdup(tmpshell) : strdup(_PATH_BSHELL);
 119         if (shell == NULL)
 120                 err(1, "strdup() failed");
 121         slashp = strrchr(shell, '/');
 122         name = (slashp != NULL) ? slashp + 1 : shell;
 123
 124         /*
 125          * If there were any %digit references, then use those, otherwise
 126          * build a new command string with sufficient %digit references at
 127          * the end to consume (nargs) arguments each time round the loop.
 128          * Allocate enough space to hold the maximum command.  Save the
 129          * size to pass to snprintf().
 130          */
 131         cmdsize = sizeof(EXEC) - 1 + strlen(argv[0])
 132             + 9 * (sizeof(" %1") - 1) + 1;
 133         if ((cmd = malloc(cmdsize)) == NULL)
 134                 err(1, NULL);
 135
 136         if (n == 0) {
 137                 /* If nargs not set, default to a single argument. */
 138                 if (nargs == -1)
 139                         nargs = 1;
 140
 141                 p = cmd;
 142                 offset = snprintf(cmd, cmdsize, EXEC "%s", argv[0]);
 143                 if ((size_t)offset >= cmdsize)
 144                         err(1, "snprintf() failed");
 145                 p += offset;
 146                 cmdsize -= offset;
 147                 for (i = 1; i <= nargs; i++) {
 148                         offset = snprintf(p, cmdsize, " %c%d", magic, i);
 149                         if ((size_t)offset >= cmdsize)
 150                                 err(1, "snprintf() failed");
 151                         p += offset;
 152                         cmdsize -= offset;
 153                 }
 154
 155                 /*
 156                  * If nargs set to the special value 0, eat a single
 157                  * argument for each command execution.
 158                  */
 159                 if (nargs == 0)
 160                         nargs = 1;
 161         } else {
 162                 offset = snprintf(cmd, cmdsize, EXEC "%s", argv[0]);
 163                 if ((size_t)offset >= cmdsize)
 164                         err(1, "snprintf() failed");
 165                 nargs = n;
 166         }
 167
 168         /*
 169          * Grab some space in which to build the command.  Allocate
 170          * as necessary later, but no reason to build it up slowly
 171          * for the normal case.
 172          */
 173         if ((c = malloc(clen = 1024)) == NULL)
 174                 err(1, NULL);
 175
 176         /*
 177          * (argc) and (argv) are still offset by one to make it simpler to
 178          * expand %digit references.  At the end of the loop check for (argc)
 179          * equals 1 means that all the (argv) has been consumed.
 180          */
 181         for (rval = 0; argc > nargs; argc -= nargs, argv += nargs) {
 182                 /*
 183                  * Find a max value for the command length, and ensure
 184                  * there's enough space to build it.
 185                  */
 186                 for (l = strlen(cmd), i = 0; i < nargs; i++)
 187                         l += strlen(argv[i+1]);
 188                 if (l > clen && (c = realloc(c, clen = l)) == NULL)
 189                         err(1, NULL);
 190
 191                 /* Expand command argv references. */
 192                 for (p = cmd, q = c; *p != '\0'; ++p) {
 193                         if (p[0] == magic && isdigit(p[1]) && p[1] != '0') {
 194                                 offset = snprintf(q, l, "%s",
 195                                     argv[(++p)[0] - '0']);
 196                                 if ((size_t)offset >= l)
 197                                         err(1, "snprintf() failed");
 198                                 q += offset;
 199                                 l -= offset;
 200                         } else {
 201                                 *q++ = *p;
 202                         }
 203                 }
 204
 205                 /* Terminate the command string. */
 206                 *q = '\0';
 207
 208                 /* Run the command. */
 209                 if (debug) {
 210                         printf("%s\n", c);
 211                 } else {
 212                         if (exec_shell(c, shell, name))
 213                                 rval = 1;
 214                 }
 215         }
 216
 217         if (argc != 1)
 218                 errx(1, "expecting additional argument%s after \"%s\"",
 219             (nargs - argc) ? "s" : "", argv[argc - 1]);
 220         free(cmd);
 221         free(c);
 222         free(shell);
 223         exit(rval);
 224 }
 225
 226 /*
 227  * exec_shell --
 228  *      Execute a shell command using passed use_shell and use_name
 229  *      arguments.
 230  */
 231 static int
 232 exec_shell(const char *command, char *use_shell, char *use_name)
 233 {
 234         pid_t pid;
 235         int omask, pstat;
 236         sig_t intsave, quitsave;
 237
 238         if (command == NULL)            /* just checking... */
 239                 return(1);
 240
 241         omask = sigblock(sigmask(SIGCHLD));
 242         switch(pid = vfork()) {
 243         case -1:                        /* error */
 244                 err(1, "vfork");
 245         case 0:                         /* child */
 246                 (void)sigsetmask(omask);
 247                 execl(use_shell, use_name, "-c", command, NULL);
 248                 warn("%s", use_shell);
 249                 _exit(1);
 250         }
 251         intsave = signal(SIGINT, SIG_IGN);
 252         quitsave = signal(SIGQUIT, SIG_IGN);
 253         pid = waitpid(pid, &pstat, 0);
 254         sigsetmask(omask);
 255         signal(SIGINT, intsave);
 256         signal(SIGQUIT, quitsave);
 257         return(pid == -1 ? -1 : pstat);
 258 }
 259
 260 void
 261 usage(void)
 262 {
 263         fprintf(stderr,
 264             "usage: apply [-a magic] [-d] [-0123456789] "
 265             "command arguments ...\n");
 266         exit(1);
 267 }