root/include/linux/vt_buffer.h

INCLUDED FROM

DEFINITIONS

1. scr_memsetw
2. scr_memcpyw
3. scr_memmovew

/*
 *      include/linux/vt_buffer.h -- Access to VT screen buffer
 *
 *      (c) 1998 Martin Mares <mj@ucw.cz>
 *
 *      This is a set of macros and functions which are used in the
 *      console driver and related code to access the screen buffer.
 *      In most cases the console works with simple in-memory buffer,
 *      but when handling hardware text mode consoles, we store
 *      the foreground console directly in video memory.
 */

#ifndef _LINUX_VT_BUFFER_H_
#define _LINUX_VT_BUFFER_H_


#if defined(CONFIG_VGA_CONSOLE) || defined(CONFIG_MDA_CONSOLE)
#include <asm/vga.h>
#endif

#ifndef VT_BUF_HAVE_RW
#define scr_writew(val, addr) (*(addr) = (val))
#define scr_readw(addr) (*(addr))
#define scr_memcpyw(d, s, c) memcpy(d, s, c)
#define scr_memmovew(d, s, c) memmove(d, s, c)
#define VT_BUF_HAVE_MEMCPYW
#define VT_BUF_HAVE_MEMMOVEW
#endif

#ifndef VT_BUF_HAVE_MEMSETW
static inline void scr_memsetw(u16 *s, u16 c, unsigned int count)
{
        count /= 2;
        while (count--)
                scr_writew(c, s++);
}
#endif

#ifndef VT_BUF_HAVE_MEMCPYW
static inline void scr_memcpyw(u16 *d, const u16 *s, unsigned int count)
{
        count /= 2;
        while (count--)
                scr_writew(scr_readw(s++), d++);
}
#endif

#ifndef VT_BUF_HAVE_MEMMOVEW
static inline void scr_memmovew(u16 *d, const u16 *s, unsigned int count)
{
        if (d < s)
                scr_memcpyw(d, s, count);
        else {
                count /= 2;
                d += count;
                s += count;
                while (count--)
                        scr_writew(scr_readw(--s), --d);
        }
}
#endif

#endif