146 lines
5.2 KiB
C
146 lines
5.2 KiB
C
#ifndef _LINUX_TTY_LDISC_H
|
|
#define _LINUX_TTY_LDISC_H
|
|
|
|
/*
|
|
* This structure defines the interface between the tty line discipline
|
|
* implementation and the tty routines. The following routines can be
|
|
* defined; unless noted otherwise, they are optional, and can be
|
|
* filled in with a null pointer.
|
|
*
|
|
* int (*open)(struct tty_struct *);
|
|
*
|
|
* This function is called when the line discipline is associated
|
|
* with the tty. The line discipline can use this as an
|
|
* opportunity to initialize any state needed by the ldisc routines.
|
|
*
|
|
* void (*close)(struct tty_struct *);
|
|
*
|
|
* This function is called when the line discipline is being
|
|
* shutdown, either because the tty is being closed or because
|
|
* the tty is being changed to use a new line discipline
|
|
*
|
|
* void (*flush_buffer)(struct tty_struct *tty);
|
|
*
|
|
* This function instructs the line discipline to clear its
|
|
* buffers of any input characters it may have queued to be
|
|
* delivered to the user mode process.
|
|
*
|
|
* ssize_t (*chars_in_buffer)(struct tty_struct *tty);
|
|
*
|
|
* This function returns the number of input characters the line
|
|
* discipline may have queued up to be delivered to the user mode
|
|
* process.
|
|
*
|
|
* ssize_t (*read)(struct tty_struct * tty, struct file * file,
|
|
* unsigned char * buf, size_t nr);
|
|
*
|
|
* This function is called when the user requests to read from
|
|
* the tty. The line discipline will return whatever characters
|
|
* it has buffered up for the user. If this function is not
|
|
* defined, the user will receive an EIO error.
|
|
*
|
|
* ssize_t (*write)(struct tty_struct * tty, struct file * file,
|
|
* const unsigned char * buf, size_t nr);
|
|
*
|
|
* This function is called when the user requests to write to the
|
|
* tty. The line discipline will deliver the characters to the
|
|
* low-level tty device for transmission, optionally performing
|
|
* some processing on the characters first. If this function is
|
|
* not defined, the user will receive an EIO error.
|
|
*
|
|
* int (*ioctl)(struct tty_struct * tty, struct file * file,
|
|
* unsigned int cmd, unsigned long arg);
|
|
*
|
|
* This function is called when the user requests an ioctl which
|
|
* is not handled by the tty layer or the low-level tty driver.
|
|
* It is intended for ioctls which affect line discpline
|
|
* operation. Note that the search order for ioctls is (1) tty
|
|
* layer, (2) tty low-level driver, (3) line discpline. So a
|
|
* low-level driver can "grab" an ioctl request before the line
|
|
* discpline has a chance to see it.
|
|
*
|
|
* void (*set_termios)(struct tty_struct *tty, struct termios * old);
|
|
*
|
|
* This function notifies the line discpline that a change has
|
|
* been made to the termios structure.
|
|
*
|
|
* int (*poll)(struct tty_struct * tty, struct file * file,
|
|
* poll_table *wait);
|
|
*
|
|
* This function is called when a user attempts to select/poll on a
|
|
* tty device. It is solely the responsibility of the line
|
|
* discipline to handle poll requests.
|
|
*
|
|
* void (*receive_buf)(struct tty_struct *, const unsigned char *cp,
|
|
* char *fp, int count);
|
|
*
|
|
* This function is called by the low-level tty driver to send
|
|
* characters received by the hardware to the line discpline for
|
|
* processing. <cp> is a pointer to the buffer of input
|
|
* character received by the device. <fp> is a pointer to a
|
|
* pointer of flag bytes which indicate whether a character was
|
|
* received with a parity error, etc.
|
|
*
|
|
* void (*write_wakeup)(struct tty_struct *);
|
|
*
|
|
* This function is called by the low-level tty driver to signal
|
|
* that line discpline should try to send more characters to the
|
|
* low-level driver for transmission. If the line discpline does
|
|
* not have any more data to send, it can just return.
|
|
*
|
|
* int (*hangup)(struct tty_struct *)
|
|
*
|
|
* Called on a hangup. Tells the discipline that it should
|
|
* cease I/O to the tty driver. Can sleep. The driver should
|
|
* seek to perform this action quickly but should wait until
|
|
* any pending driver I/O is completed.
|
|
*/
|
|
|
|
#include <linux/fs.h>
|
|
#include <linux/wait.h>
|
|
|
|
struct tty_ldisc {
|
|
int magic;
|
|
char *name;
|
|
int num;
|
|
int flags;
|
|
|
|
/*
|
|
* The following routines are called from above.
|
|
*/
|
|
int (*open)(struct tty_struct *);
|
|
void (*close)(struct tty_struct *);
|
|
void (*flush_buffer)(struct tty_struct *tty);
|
|
ssize_t (*chars_in_buffer)(struct tty_struct *tty);
|
|
ssize_t (*read)(struct tty_struct * tty, struct file * file,
|
|
unsigned char __user * buf, size_t nr);
|
|
ssize_t (*write)(struct tty_struct * tty, struct file * file,
|
|
const unsigned char * buf, size_t nr);
|
|
int (*ioctl)(struct tty_struct * tty, struct file * file,
|
|
unsigned int cmd, unsigned long arg);
|
|
void (*set_termios)(struct tty_struct *tty, struct termios * old);
|
|
unsigned int (*poll)(struct tty_struct *, struct file *,
|
|
struct poll_table_struct *);
|
|
int (*hangup)(struct tty_struct *tty);
|
|
|
|
/*
|
|
* The following routines are called from below.
|
|
*/
|
|
void (*receive_buf)(struct tty_struct *, const unsigned char *cp,
|
|
char *fp, int count);
|
|
void (*write_wakeup)(struct tty_struct *);
|
|
|
|
struct module *owner;
|
|
|
|
int refcount;
|
|
};
|
|
|
|
#define TTY_LDISC_MAGIC 0x5403
|
|
|
|
#define LDISC_FLAG_DEFINED 0x00000001
|
|
|
|
#define MODULE_ALIAS_LDISC(ldisc) \
|
|
MODULE_ALIAS("tty-ldisc-" __stringify(ldisc))
|
|
|
|
#endif /* _LINUX_TTY_LDISC_H */
|