// SPDX-License-Identifier: GPL-2.0
#include <linux/termios_internal.h>

/*
 * c_cc characters in the termio structure.  Oh, how I love being
 * backwardly compatible.  Notice that character 4 and 5 are
 * interpreted differently depending on whether ICANON is set in
 * c_lflag.  If it's set, they are used as _VEOF and _VEOL, otherwise
 * as _VMIN and V_TIME.  This is for compatibility with OSF/1 (which
 * is compatible with sysV)...
 */
#define _VMIN   4
#define _VTIME  5

int kernel_termios_to_user_termio(struct termio __user *termio,
                                                struct ktermios *termios)
{
        struct termio v;
        memset(&v, 0, sizeof(struct termio));
        v.c_iflag = termios->c_iflag;
        v.c_oflag = termios->c_oflag;
        v.c_cflag = termios->c_cflag;
        v.c_lflag = termios->c_lflag;
        v.c_line = termios->c_line;
        memcpy(v.c_cc, termios->c_cc, NCC);
        if (!(v.c_lflag & ICANON)) {
                v.c_cc[_VMIN] = termios->c_cc[VMIN];
                v.c_cc[_VTIME] = termios->c_cc[VTIME];
        }
        return copy_to_user(termio, &v, sizeof(struct termio));
}

int user_termios_to_kernel_termios(struct ktermios *k,
                                                 struct termios2 __user *u)
{
        int err;
        err  = get_user(k->c_iflag, &u->c_iflag);
        err |= get_user(k->c_oflag, &u->c_oflag);
        err |= get_user(k->c_cflag, &u->c_cflag);
        err |= get_user(k->c_lflag, &u->c_lflag);
        err |= get_user(k->c_line,  &u->c_line);
        err |= copy_from_user(k->c_cc, u->c_cc, NCCS);
        if (k->c_lflag & ICANON) {
                err |= get_user(k->c_cc[VEOF], &u->c_cc[VEOF]);
                err |= get_user(k->c_cc[VEOL], &u->c_cc[VEOL]);
        } else {
                err |= get_user(k->c_cc[VMIN],  &u->c_cc[_VMIN]);
                err |= get_user(k->c_cc[VTIME], &u->c_cc[_VTIME]);
        }
        err |= get_user(k->c_ispeed,  &u->c_ispeed);
        err |= get_user(k->c_ospeed,  &u->c_ospeed);
        return err;
}

int kernel_termios_to_user_termios(struct termios2 __user *u,
                                                 struct ktermios *k)
{
        int err;
        err  = put_user(k->c_iflag, &u->c_iflag);
        err |= put_user(k->c_oflag, &u->c_oflag);
        err |= put_user(k->c_cflag, &u->c_cflag);
        err |= put_user(k->c_lflag, &u->c_lflag);
        err |= put_user(k->c_line, &u->c_line);
        err |= copy_to_user(u->c_cc, k->c_cc, NCCS);
        if (!(k->c_lflag & ICANON)) {
                err |= put_user(k->c_cc[VMIN],  &u->c_cc[_VMIN]);
                err |= put_user(k->c_cc[VTIME], &u->c_cc[_VTIME]);
        } else {
                err |= put_user(k->c_cc[VEOF], &u->c_cc[VEOF]);
                err |= put_user(k->c_cc[VEOL], &u->c_cc[VEOL]);
        }
        err |= put_user(k->c_ispeed, &u->c_ispeed);
        err |= put_user(k->c_ospeed, &u->c_ospeed);
        return err;
}

int user_termios_to_kernel_termios_1(struct ktermios *k,
                                                 struct termios __user *u)
{
        int err;
        err  = get_user(k->c_iflag, &u->c_iflag);
        err |= get_user(k->c_oflag, &u->c_oflag);
        err |= get_user(k->c_cflag, &u->c_cflag);
        err |= get_user(k->c_lflag, &u->c_lflag);
        err |= get_user(k->c_line,  &u->c_line);
        err |= copy_from_user(k->c_cc, u->c_cc, NCCS);
        if (k->c_lflag & ICANON) {
                err |= get_user(k->c_cc[VEOF], &u->c_cc[VEOF]);
                err |= get_user(k->c_cc[VEOL], &u->c_cc[VEOL]);
        } else {
                err |= get_user(k->c_cc[VMIN],  &u->c_cc[_VMIN]);
                err |= get_user(k->c_cc[VTIME], &u->c_cc[_VTIME]);
        }
        return err;
}

int kernel_termios_to_user_termios_1(struct termios __user *u,
                                                 struct ktermios *k)
{
        int err;
        err  = put_user(k->c_iflag, &u->c_iflag);
        err |= put_user(k->c_oflag, &u->c_oflag);
        err |= put_user(k->c_cflag, &u->c_cflag);
        err |= put_user(k->c_lflag, &u->c_lflag);
        err |= put_user(k->c_line, &u->c_line);
        err |= copy_to_user(u->c_cc, k->c_cc, NCCS);
        if (!(k->c_lflag & ICANON)) {
                err |= put_user(k->c_cc[VMIN],  &u->c_cc[_VMIN]);
                err |= put_user(k->c_cc[VTIME], &u->c_cc[_VTIME]);
        } else {
                err |= put_user(k->c_cc[VEOF], &u->c_cc[VEOF]);
                err |= put_user(k->c_cc[VEOL], &u->c_cc[VEOL]);
        }
        return err;
}