#pragma once

// Pseudo-terminals, Unix98 style: open /dev/ptmx and get the master side of a
// new pair; the slave is /dev/pts/N. What sits between the two is the same
// line discipline a console has. See kernel/dev/pty.c.

#include "core/types.h"

#define PTMX_MAJOR  13      // /dev/ptmx: opening it allocates a pair
#define PTM_MAJOR   14      // a master, minor = pair number; never in a listing
#define PTS_MAJOR   15      // /dev/pts/N
#define NPTY        32

// A controlling terminal that is a pty, in proc->ctty: PTY_CTTY + N. The
// console's are 1..NVT.
#define PTY_CTTY    64

struct inode;
struct file;

int  pty_alloc(void);                // the new pair's number, or -1
int  pty_used(int n);
int  pty_ioctl(struct inode *ip, uint request, addr_t arg);
int  pty_poll(struct inode *ip, int events, int readable, int writable);
struct inode *ptmx_open(struct inode *ip);  // ip locked; returns the master, locked
void pty_init(void);

// Lines the devsw table needs.
int  ptm_read(struct inode*, uint64, char*, int);
int  ptm_write(struct inode*, uint64, char*, int);
int  ptm_ready(struct inode*);
void ptm_open(struct inode*);
void ptm_close(struct inode*);
int  pts_read(struct inode*, uint64, char*, int);
int  pts_write(struct inode*, uint64, char*, int);
int  pts_ready(struct inode*);
void pts_open(struct inode*);
void pts_close(struct inode*);

// From kernel/fs/devfs.c: the inode of master N.
struct inode *devfs_pty_master(int n);