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/* $OpenBSD: apply.c,v 1.27 2015/10/10 17:48:34 deraadt Exp $ */
/* $NetBSD: apply.c,v 1.3 1995/03/25 03:38:23 glass Exp $ */
/*-
* Copyright (c) 1994
* The Regents of the University of California. All rights reserved.
*
* This code is derived from software contributed to Berkeley by
* Jan-Simon Pendry.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#include <sys/wait.h>
#include <ctype.h>
#include <err.h>
#include <paths.h>
#include <signal.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
__dead void usage(void);
static int mysystem(const char *);
int
main(int argc, char *argv[])
{
int ch, clen, debug, i, l, magic, n, nargs, rval;
char *c, *c2, *cmd, *p, *q;
size_t len;
if (pledge("stdio proc exec", NULL) == -1)
err(1, "pledge");
debug = 0;
magic = '%'; /* Default magic char is `%'. */
nargs = -1;
while ((ch = getopt(argc, argv, "a:d0123456789")) != -1)
switch (ch) {
case 'a':
if (optarg[1] != '\0')
errx(1,
"illegal magic character specification.");
magic = optarg[0];
break;
case 'd':
debug = 1;
break;
case '0': case '1': case '2': case '3': case '4':
case '5': case '6': case '7': case '8': case '9':
if (nargs != -1)
errx(1,
"only one -# argument may be specified.");
nargs = ch - '0';
break;
default:
usage();
}
argc -= optind;
argv += optind;
if (argc < 2)
usage();
/*
* The command to run is argv[0], and the args are argv[1..].
* Look for %digit references in the command, remembering the
* largest one.
*/
for (n = 0, p = argv[0]; *p != '\0'; ++p)
if (p[0] == magic &&
isdigit((unsigned char)p[1]) && p[1] != '0') {
++p;
if (p[0] - '0' > n)
n = p[0] - '0';
}
/*
* If there were any %digit references, then use those, otherwise
* build a new command string with sufficient %digit references at
* the end to consume (nargs) arguments each time round the loop.
* Allocate enough space to hold the maximum command.
*/
if (n == 0) {
len = sizeof("exec ") - 1 +
strlen(argv[0]) + 9 * (sizeof(" %1") - 1) + 1;
if ((cmd = malloc(len)) == NULL)
err(1, NULL);
/* If nargs not set, default to a single argument. */
if (nargs == -1)
nargs = 1;
l = snprintf(cmd, len, "exec %s", argv[0]);
if (l >= len || l == -1)
errx(1, "error building exec string");
len -= l;
p = cmd + l;
for (i = 1; i <= nargs; i++) {
l = snprintf(p, len, " %c%d", magic, i);
if (l >= len || l == -1)
errx(1, "error numbering arguments");
len -= l;
p += l;
}
/*
* If nargs set to the special value 0, eat a single
* argument for each command execution.
*/
if (nargs == 0)
nargs = 1;
} else {
if (asprintf(&cmd, "exec %s", argv[0]) == -1)
err(1, NULL);
nargs = n;
}
/*
* Grab some space in which to build the command. Allocate
* as necessary later, but no reason to build it up slowly
* for the normal case.
*/
if ((c = malloc(clen = 1024)) == NULL)
err(1, NULL);
/*
* (argc) and (argv) are still offset by one to make it simpler to
* expand %digit references. At the end of the loop check for (argc)
* equals 1 means that all the (argv) has been consumed.
*/
for (rval = 0; argc > nargs; argc -= nargs, argv += nargs) {
/*
* Find a max value for the command length, and ensure
* there's enough space to build it.
*/
for (l = strlen(cmd), i = 0; i < nargs; i++)
l += strlen(argv[i+1]);
if (l > clen) {
if ((c2 = realloc(c, l)) == NULL)
err(1, NULL);
c = c2;
clen = l;
}
/* Expand command argv references. */
for (p = cmd, q = c; *p != '\0'; ++p)
if (p[0] == magic &&
isdigit((unsigned char)p[1]) && p[1] != '0') {
strlcpy(q, argv[(++p)[0] - '0'], c + clen - q);
q += strlen(q);
} else
*q++ = *p;
/* Terminate the command string. */
*q = '\0';
/* Run the command. */
if (debug)
(void)printf("%s\n", c);
else if (mysystem(c))
rval = 1;
}
if (argc != 1)
errx(1, "expecting additional argument%s after \"%s\"",
(nargs - argc) ? "s" : "", argv[argc - 1]);
exit(rval);
}
/*
* mysystem --
* Private version of system(3). Use the user's SHELL environment
* variable as the shell to execute.
*/
static int
mysystem(const char *command)
{
static const char *name, *shell;
pid_t pid;
int pstat;
sigset_t mask, omask;
sig_t intsave, quitsave;
if (shell == NULL) {
if ((shell = getenv("SHELL")) == NULL)
shell = _PATH_BSHELL;
if ((name = strrchr(shell, '/')) == NULL)
name = shell;
else
++name;
}
if (!command) /* just checking... */
return(1);
sigemptyset(&mask);
sigaddset(&mask, SIGCHLD);
sigprocmask(SIG_BLOCK, &mask, &omask);
switch(pid = fork()) {
case -1: /* error */
err(1, "fork");
case 0: /* child */
sigprocmask(SIG_SETMASK, &omask, NULL);
execl(shell, name, "-c", command, (char *)NULL);
err(1, "%s", shell);
}
intsave = signal(SIGINT, SIG_IGN);
quitsave = signal(SIGQUIT, SIG_IGN);
pid = waitpid(pid, &pstat, 0);
sigprocmask(SIG_SETMASK, &omask, NULL);
(void)signal(SIGINT, intsave);
(void)signal(SIGQUIT, quitsave);
return(pid == -1 ? -1 : pstat);
}
__dead void
usage(void)
{
(void)fprintf(stderr,
"usage: apply [-#] [-d] [-a magic] command argument ...\n");
exit(1);
}
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