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/*-
* Copyright (c) 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009,
* 2010, 2011, 2012, 2013, 2014, 2015, 2016, 2017
* mirabilos <m@mirbsd.org>
*
* Provided that these terms and disclaimer and all copyright notices
* are retained or reproduced in an accompanying document, permission
* is granted to deal in this work without restriction, including un-
* limited rights to use, publicly perform, distribute, sell, modify,
* merge, give away, or sublicence.
*
* This work is provided "AS IS" and WITHOUT WARRANTY of any kind, to
* the utmost extent permitted by applicable law, neither express nor
* implied; without malicious intent or gross negligence. In no event
* may a licensor, author or contributor be held liable for indirect,
* direct, other damage, loss, or other issues arising in any way out
* of dealing in the work, even if advised of the possibility of such
* damage or existence of a defect, except proven that it results out
* of said person's immediate fault when using the work as intended.
*/
#include <errno.h>
#include <fcntl.h>
#include <signal.h>
#include <stdint.h>
#include <string.h>
#include <unistd.h>
#define MKSH_CAT_BUFSIZ 256
#ifndef O_BINARY
#define O_BINARY 0
#endif
#define ksh_sigmask(sig) (((sig) < 1 || (sig) > 127) ? 255 : 128 + (sig))
static char buf[MKSH_CAT_BUFSIZ];
static volatile sig_atomic_t intrsig;
static const char Tsynerr[] = "cat: syntax error\n";
static const char unkerr_msg[] = "Unknown error";
static const char sigint_msg[] = " ...\ncat: Interrupted\n";
static void
disperr(const char *fn)
{
int e = errno;
write(2, "cat: ", 5);
write(2, fn, strlen(fn));
write(2, ": ", 2);
if (strerror_r(e, buf, MKSH_CAT_BUFSIZ))
write(2, unkerr_msg, sizeof(unkerr_msg) - 1);
else
write(2, buf, strlen(buf));
write(2, "\n", 1);
}
static void
sighandler(int signo __attribute__((__unused__)))
{
intrsig = 1;
}
int
main(int argc __attribute__((__unused__)), char *wp[])
{
int fd = 0, rv;
ssize_t n, w;
const char *fn = "<stdin>";
char *cp;
++wp;
/* parse options (POSIX demands this) */
while ((cp = *wp) && *cp++ == '-') {
if (!cp[0])
break;
if (cp[0] == '-' && !cp[1]) {
++wp;
break;
}
while (*cp == 'u')
++cp;
if (*cp) {
write(2, Tsynerr, sizeof(Tsynerr) - 1);
return (1);
}
++wp;
}
rv = 0;
/* catch SIGPIPE */
signal(SIGPIPE, SIG_IGN);
/* abort on SIGINT */
signal(SIGINT, sighandler);
do {
if (*wp) {
fn = *wp++;
if (fn[0] == '-' && !fn[1])
fd = 0;
else if ((fd = open(fn, O_RDONLY | O_BINARY)) < 0) {
disperr(fn);
rv = 1;
continue;
}
}
while (/* CONSTCOND */ 1) {
if ((n = read(fd, (cp = buf), MKSH_CAT_BUFSIZ)) == -1) {
if (errno == EINTR) {
/* give the user a chance to ^C out */
if (intrsig)
goto has_intrsig;
/* interrupted, try again */
continue;
}
/* an error occured during reading */
disperr(fn);
rv = 1;
break;
} else if (n == 0)
/* end of file reached */
break;
while (n) {
if (intrsig)
goto has_intrsig;
if ((w = write(1, cp, n)) != -1) {
n -= w;
cp += w;
continue;
}
if (errno == EINTR) {
has_intrsig:
/* give the user a chance to ^C out */
if (intrsig) {
write(2, sigint_msg,
sizeof(sigint_msg) - 1);
return (ksh_sigmask(SIGINT));
}
/* interrupted, try again */
continue;
}
if (errno == EPIPE) {
/* fake receiving signal */
rv = ksh_sigmask(SIGPIPE);
} else {
/* an error occured during writing */
disperr("<stdout>");
rv = 1;
}
if (fd != 0)
close(fd);
goto out;
}
}
if (fd != 0)
close(fd);
} while (*wp);
out:
return (rv);
}
|
