Linux-2.6.12-rc2v2.6.12-rc2

Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!

1 files changed, 154 insertions, 0 deletions

diff --git a/include/linux/tty_ldisc.h b/include/linux/tty_ldisc.h
new file mode 100644
index 000000000000..6066afde5ce4
--- /dev/null
+++ b/include/linux/tty_ldisc.h
@@ -0,0 +1,154 @@
+#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.
+ * 
+ * int	(*receive_room)(struct tty_struct *);
+ *
+ * 	This function is called by the low-level tty driver to
+ * 	determine how many characters the line discpline can accept.
+ * 	The low-level driver must not send more characters than was
+ * 	indicated by receive_room, or the line discpline may drop
+ * 	those characters.
+ * 
+ * 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);
+	int	(*receive_room)(struct tty_struct *);
+	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 */