busybox/init/mesg.c
Denys Vlasenko b9f2d9f7d9 mass removal of underscores from _BB_DIR_foo and _BB_SUID_foo
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2011-01-18 13:58:01 +01:00

67 lines
1.6 KiB
C

/* vi: set sw=4 ts=4: */
/*
* mesg implementation for busybox
*
* Copyright (c) 2002 Manuel Novoa III <mjn3@codepoet.org>
*
* Licensed under GPLv2 or later, see file LICENSE in this source tree.
*/
//applet:IF_MESG(APPLET(mesg, BB_DIR_USR_BIN, BB_SUID_DROP))
//kbuild:lib-$(CONFIG_MESG) += mesg.o
//config:config MESG
//config: bool "mesg"
//config: default y
//config: help
//config: Mesg controls access to your terminal by others. It is typically
//config: used to allow or disallow other users to write to your terminal
//usage:#define mesg_trivial_usage
//usage: "[y|n]"
//usage:#define mesg_full_usage "\n\n"
//usage: "Control write access to your terminal\n"
//usage: " y Allow write access to your terminal\n"
//usage: " n Disallow write access to your terminal"
#include "libbb.h"
#ifdef USE_TTY_GROUP
#define S_IWGRP_OR_S_IWOTH S_IWGRP
#else
#define S_IWGRP_OR_S_IWOTH (S_IWGRP | S_IWOTH)
#endif
int mesg_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
int mesg_main(int argc UNUSED_PARAM, char **argv)
{
struct stat sb;
const char *tty;
char c = 0;
argv++;
if (!argv[0]
|| (!argv[1] && ((c = argv[0][0]) == 'y' || c == 'n'))
) {
tty = xmalloc_ttyname(STDERR_FILENO);
if (tty == NULL) {
tty = "ttyname";
} else if (stat(tty, &sb) == 0) {
mode_t m;
if (c == 0) {
puts((sb.st_mode & (S_IWGRP|S_IWOTH)) ? "is y" : "is n");
return EXIT_SUCCESS;
}
m = (c == 'y') ? sb.st_mode | S_IWGRP_OR_S_IWOTH
: sb.st_mode & ~(S_IWGRP|S_IWOTH);
if (chmod(tty, m) == 0) {
return EXIT_SUCCESS;
}
}
bb_simple_perror_msg_and_die(tty);
}
bb_show_usage();
}