mirror of
https://github.com/ibm-s390-linux/s390-tools.git
synced 2026-08-05 02:14:52 +00:00
Initial s390-tools-2.0.0 import
This commit is based on the s390-tools-1.39.0 version. Changes on top of s390-tools-1.39.0: - Add MIT license to all source files - Add LICENSE file - Transform REAMDE to README.md (markdown) - Add AUTHORS.md file - Add CONTRIBUTING.md file - Move changelog from README to CHANGELOG.md file Reviewed-by: Stefan Haberland <sth@linux.vnet.ibm.com> Signed-off-by: Michael Holzheu <holzheu@linux.vnet.ibm.com>
This commit is contained in:
Michael Holzheu
@@ -0,0 +1,192 @@
|
||||
/*
|
||||
* ttyrun - Start a program if a specified terminal device is available
|
||||
*
|
||||
*
|
||||
* ttyrun is typically used to prevent a respawn through the init(8)
|
||||
* program when a terminal is not available.
|
||||
* ttyrun runs the specific program if the specified terminal device
|
||||
* can be opened successfully. Otherwise the program enters a sleep or
|
||||
* exits with a specified return value.
|
||||
*
|
||||
* Example: To start /sbin/agetty on terminal device hvc1, use:
|
||||
*
|
||||
* h1:2345:respawn:/sbin/ttyrun hvc1 /sbin/agetty -L 9600 %t linux
|
||||
*
|
||||
* Note: %t is resolved to the terminal device "hvc1" before /sbin/agetty
|
||||
* is started.
|
||||
*
|
||||
* Return values:
|
||||
* 1 - invalid argument or parameter is missing
|
||||
* 2 - terminal does not resolve to a terminal device
|
||||
* 3 - starting the specified program failed
|
||||
* 1..255 - terminal is not available and the return code is
|
||||
* specified with the -e option
|
||||
*
|
||||
* Copyright 2017 IBM Corp.
|
||||
*
|
||||
* s390-tools is free software; you can redistribute it and/or modify
|
||||
* it under the terms of the MIT license. See LICENSE for details.
|
||||
*/
|
||||
#include <errno.h>
|
||||
#include <fcntl.h>
|
||||
#include <getopt.h>
|
||||
#include <limits.h>
|
||||
#include <signal.h>
|
||||
#include <stdio.h>
|
||||
#include <stdlib.h>
|
||||
#include <string.h>
|
||||
#include <sys/types.h>
|
||||
#include <syslog.h>
|
||||
#include <unistd.h>
|
||||
|
||||
#include "lib/zt_common.h"
|
||||
|
||||
|
||||
#define TTY_ESCAPE_STR "%t"
|
||||
|
||||
#define EXIT_INVALID_ARG 1
|
||||
#define EXIT_NO_TERMINAL 2
|
||||
#define EXIT_EXEC_FAILED 3
|
||||
|
||||
|
||||
static const char usage[] =
|
||||
"Usage: %s [-e status] <term> <program> [<program_options>]\n"
|
||||
" %s [-h|--help] [-v|--version]\n"
|
||||
"\n"
|
||||
"Start the program if the specified terminal device is available.\n"
|
||||
"If the terminal device cannot be opened, sleep until a signal is received\n"
|
||||
"that causes an exit or exit with the return value specified with status.\n"
|
||||
"\n"
|
||||
"-e, --exitstatus Specifies an exit status in the range 1 to 255.\n"
|
||||
"-V, --verbose Displays syslog messages.\n"
|
||||
"-h, --help Displays this help, then exits.\n"
|
||||
"-v, --version Displays version information, then exits.\n";
|
||||
|
||||
static void help_exit(const char *prg)
|
||||
{
|
||||
printf(usage, prg, prg);
|
||||
exit(EXIT_SUCCESS);
|
||||
}
|
||||
|
||||
static void version_exit(const char *prg)
|
||||
{
|
||||
printf("%s: Start a program if a terminal device is available, "
|
||||
"version %s\n", prg, RELEASE_STRING);
|
||||
printf("Copyright IBM Corp. 2010, 2017\n");
|
||||
exit(EXIT_SUCCESS);
|
||||
}
|
||||
|
||||
static void err_exit(const char *prg, const char *msg)
|
||||
{
|
||||
fprintf(stderr, "%s: %s\n", prg, msg);
|
||||
exit(EXIT_INVALID_ARG);
|
||||
}
|
||||
|
||||
static void wait_and_exit(void)
|
||||
{
|
||||
/* sleep until a signal is received, then exit */
|
||||
pause();
|
||||
exit(EXIT_SUCCESS);
|
||||
}
|
||||
|
||||
static const struct option prog_opts[] = {
|
||||
{ "help", no_argument, NULL, 'h'},
|
||||
{ "version", no_argument, NULL, 'v'},
|
||||
{ "exitstatus", required_argument, NULL, 'e'},
|
||||
{ "verbose", no_argument, NULL, 'V'},
|
||||
{ NULL, no_argument, NULL, 0 },
|
||||
};
|
||||
|
||||
int main(int argc, char *argv[])
|
||||
{
|
||||
int rc, tty, i, c, index, done, term_index, verbose;
|
||||
char terminal[PATH_MAX] = "";
|
||||
unsigned long exitstatus;
|
||||
|
||||
|
||||
/* parse command options */
|
||||
if (argc == 1)
|
||||
err_exit(argv[0], "One or more options are required but missing");
|
||||
|
||||
exitstatus = done = term_index = verbose = 0;
|
||||
while (!done) {
|
||||
c = getopt_long(argc, argv, "-hve:V", prog_opts, NULL);
|
||||
switch (c) {
|
||||
case -1:
|
||||
done = 1;
|
||||
break;
|
||||
case 1:
|
||||
/* the first non-optional argument must be the
|
||||
* terminal device */
|
||||
if (!strncmp(optarg, "/", 1))
|
||||
strncpy(terminal, optarg, PATH_MAX - 1);
|
||||
else
|
||||
snprintf(terminal, PATH_MAX, "/dev/%s", optarg);
|
||||
terminal[PATH_MAX - 1] = 0;
|
||||
term_index = optind - 1;
|
||||
done = 1;
|
||||
break;
|
||||
case 'e':
|
||||
errno = 0;
|
||||
exitstatus = strtoul(optarg, (char **) NULL, 10);
|
||||
if (errno == ERANGE)
|
||||
err_exit(argv[0], "The exit status must be "
|
||||
"an integer in the range 1 to 255");
|
||||
|
||||
if (!exitstatus || exitstatus > 255)
|
||||
err_exit(argv[0], "The exit status must be "
|
||||
"in the range 1 to 255");
|
||||
break;
|
||||
case 'V':
|
||||
verbose = 1;
|
||||
break;
|
||||
case 'h':
|
||||
help_exit(argv[0]);
|
||||
case 'v':
|
||||
version_exit(argv[0]);
|
||||
case '?':
|
||||
fprintf(stderr, "Try %s --help for more information\n",
|
||||
argv[0]);
|
||||
exit(EXIT_INVALID_ARG);
|
||||
}
|
||||
}
|
||||
index = optind;
|
||||
|
||||
/* check terminal */
|
||||
if (!strlen(terminal))
|
||||
err_exit(argv[0], "You must specify the name of "
|
||||
"a terminal device");
|
||||
|
||||
/* any program to start? */
|
||||
if (index == argc)
|
||||
err_exit(argv[0], "You must specify a program to start");
|
||||
|
||||
/* open and check terminal device */
|
||||
tty = open(terminal, O_NOCTTY | O_RDONLY | O_NONBLOCK);
|
||||
if (tty == -1) {
|
||||
if (verbose) {
|
||||
openlog(argv[0], LOG_PID, LOG_DAEMON);
|
||||
syslog(LOG_INFO, "Could not open tty %s (%s)",
|
||||
terminal, strerror(errno));
|
||||
closelog();
|
||||
}
|
||||
|
||||
/* enter wait or exit */
|
||||
if (exitstatus)
|
||||
exit(exitstatus);
|
||||
wait_and_exit();
|
||||
}
|
||||
rc = !isatty(tty);
|
||||
close(tty);
|
||||
if (rc)
|
||||
exit(EXIT_NO_TERMINAL);
|
||||
|
||||
/* start getty program */
|
||||
for (i = index; i < argc; i++)
|
||||
if (!strcmp(argv[i], TTY_ESCAPE_STR) && term_index)
|
||||
argv[i] = argv[term_index];
|
||||
if (execv(argv[index], argv + index))
|
||||
exit(EXIT_EXEC_FAILED);
|
||||
|
||||
exit(EXIT_SUCCESS);
|
||||
}
|
||||
Reference in New Issue
Block a user