freebsd-dev/bin/echo/echo.c
Warner Losh fbbd9655e5 Renumber copyright clause 4
Renumber cluase 4 to 3, per what everybody else did when BSD granted
them permission to remove clause 3. My insistance on keeping the same
numbering for legal reasons is too pedantic, so give up on that point.

Submitted by:	Jan Schaumann <jschauma@stevens.edu>
Pull Request:	https://github.com/freebsd/freebsd/pull/96
2017-02-28 23:42:47 +00:00

143 lines
4.1 KiB
C

/*-
* Copyright (c) 1989, 1993
* The Regents of the University of California. All rights reserved.
*
* 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.
*/
#if 0
#ifndef lint
static char const copyright[] =
"@(#) Copyright (c) 1989, 1993\n\
The Regents of the University of California. All rights reserved.\n";
#endif /* not lint */
#ifndef lint
static char sccsid[] = "@(#)echo.c 8.1 (Berkeley) 5/31/93";
#endif /* not lint */
#endif
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include <sys/types.h>
#include <sys/uio.h>
#include <assert.h>
#include <capsicum_helpers.h>
#include <err.h>
#include <errno.h>
#include <limits.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
/*
* Report an error and exit.
* Use it instead of err(3) to avoid linking-in stdio.
*/
static __dead2 void
errexit(const char *prog, const char *reason)
{
char *errstr = strerror(errno);
write(STDERR_FILENO, prog, strlen(prog));
write(STDERR_FILENO, ": ", 2);
write(STDERR_FILENO, reason, strlen(reason));
write(STDERR_FILENO, ": ", 2);
write(STDERR_FILENO, errstr, strlen(errstr));
write(STDERR_FILENO, "\n", 1);
exit(1);
}
int
main(int argc, char *argv[])
{
int nflag; /* if not set, output a trailing newline. */
int veclen; /* number of writev arguments. */
struct iovec *iov, *vp; /* Elements to write, current element. */
char space[] = " ";
char newline[] = "\n";
char *progname = argv[0];
if (caph_limit_stdio() < 0 || (cap_enter() < 0 && errno != ENOSYS))
err(1, "capsicum");
/* This utility may NOT do getopt(3) option parsing. */
if (*++argv && !strcmp(*argv, "-n")) {
++argv;
--argc;
nflag = 1;
} else
nflag = 0;
veclen = (argc >= 2) ? (argc - 2) * 2 + 1 : 0;
if ((vp = iov = malloc((veclen + 1) * sizeof(struct iovec))) == NULL)
errexit(progname, "malloc");
while (argv[0] != NULL) {
size_t len;
len = strlen(argv[0]);
/*
* If the next argument is NULL then this is this
* the last argument, therefore we need to check
* for a trailing \c.
*/
if (argv[1] == NULL) {
/* is there room for a '\c' and is there one? */
if (len >= 2 &&
argv[0][len - 2] == '\\' &&
argv[0][len - 1] == 'c') {
/* chop it and set the no-newline flag. */
len -= 2;
nflag = 1;
}
}
vp->iov_base = *argv;
vp++->iov_len = len;
if (*++argv) {
vp->iov_base = space;
vp++->iov_len = 1;
}
}
if (!nflag) {
veclen++;
vp->iov_base = newline;
vp++->iov_len = 1;
}
/* assert(veclen == (vp - iov)); */
while (veclen) {
int nwrite;
nwrite = (veclen > IOV_MAX) ? IOV_MAX : veclen;
if (writev(STDOUT_FILENO, iov, nwrite) == -1)
errexit(progname, "write");
iov += nwrite;
veclen -= nwrite;
}
return 0;
}