// SPDX-License-Identifier: GPL-2.0/* * Copyright (C) 2002 - 2007 Jeff Dike (jdike@{addtoit,linux.intel}.com) */ #include <stdlib.h>#include <unistd.h>#include <errno.h>#include <fcntl.h>#include <kern_util.h>#include <os.h> struct grantpt_info {	int fd;	int res;	int err;}; static void grantpt_cb(void *arg){	struct grantpt_info *info = arg; 	info->res = grantpt(info->fd);	info->err = errno;} int get_pty(void){	struct grantpt_info info;	int fd, err; 	fd = open("/dev/ptmx", O_RDWR);	if (fd < 0) {		err = -errno;		printk(UM_KERN_ERR "get_pty : Couldn't open /dev/ptmx - "		       "err = %d\n", errno);		return err;	} 	info.fd = fd;	initial_thread_cb(grantpt_cb, &info); 	if (info.res < 0) {		err = -info.err;		printk(UM_KERN_ERR "get_pty : Couldn't grant pty - "		       "errno = %d\n", -info.err);		goto out;	} 	if (unlockpt(fd) < 0) {		err = -errno;		printk(UM_KERN_ERR "get_pty : Couldn't unlock pty - "		       "errno = %d\n", errno);		goto out;	}	return fd;out:	close(fd);	return err;}