Linux-2.6.12-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 */