C++ scr_readw函数代码示例

static int
promcon_start(struct vc_data *conp, char *b)
{
	unsigned short *s = (unsigned short *)
			(conp->vc_origin + py * conp->vc_size_row + (px << 1));
	u16 cs;

	cs = scr_readw(s);
	if (px == pw) {
		unsigned short *t = s - 1;
		u16 ct = scr_readw(t);

		if (inverted(cs) && inverted(ct))
			return sprintf(b, "\b\033[7m%c\b\033[@%c\033[m", cs,
				       ct);
		else if (inverted(cs))
			return sprintf(b, "\b\033[7m%c\033[m\b\033[@%c", cs,
				       ct);
		else if (inverted(ct))
			return sprintf(b, "\b%c\b\033[@\033[7m%c\033[m", cs,
				       ct);
		else
			return sprintf(b, "\b%c\b\033[@%c", cs, ct);
	}

	if (inverted(cs))
		return sprintf(b, "\033[7m%c\033[m\b", cs);
	else
		return sprintf(b, "%c\b", cs);
}

void fbcon_mfb_putcs(struct vc_data *conp, struct display *p, 
		     const unsigned short *s, int count, int yy, int xx)
{
    u8 *dest, *dest0, *cdat;
    u_int rows, bold, revs, underl;
    u8 d;
    u16 c;

    dest0 = p->screen_base+yy*fontheight(p)*p->next_line+xx;
    bold = attr_bold(p,scr_readw(s));
    revs = attr_reverse(p,scr_readw(s));
    underl = attr_underline(p,scr_readw(s));

    while (count--) {
	c = scr_readw(s++) & p->charmask;
	dest = dest0++;
	cdat = p->fontdata+c*fontheight(p);
	for (rows = fontheight(p); rows--; dest += p->next_line) {
	    d = *cdat++;
	    if (underl && !rows)
		d = 0xff;
	    else if (bold)
		d |= d>>1;
	    if (revs)
		d = ~d;
	    *dest = d;
	}
    }
}

static int
promcon_end(struct vc_data *conp, char *b)
{
	unsigned short *s = (unsigned short *)
			(conp->vc_origin + py * conp->vc_size_row + (px << 1));
	char *p = b;
	u16 cs;

	b += sprintf(b, "\033[%d;%dH", py + 1, px + 1);

	cs = scr_readw(s);
	if (px == pw) {
		unsigned short *t = s - 1;
		u16 ct = scr_readw(t);

		if (inverted(cs) && inverted(ct))
			b += sprintf(b, "\b%c\b\033[@\033[7m%c\033[m", cs, ct);
		else if (inverted(cs))
			b += sprintf(b, "\b%c\b\033[@%c", cs, ct);
		else if (inverted(ct))
			b += sprintf(b, "\b\033[7m%c\b\033[@%c\033[m", cs, ct);
		else
			b += sprintf(b, "\b\033[7m%c\033[m\b\033[@%c", cs, ct);
		return b - p;
	}

	if (inverted(cs))
		b += sprintf(b, "%c\b", cs);
	else
		b += sprintf(b, "\033[7m%c\033[m\b", cs);
	return b - p;
}

static void sticon_putcs(struct vc_data *conp, const unsigned short *s,
			 int count, int ypos, int xpos)
{
    int redraw_cursor = 0;

    if (vga_is_gfx || console_blanked)
	    return;

    if (conp->vc_mode != KD_TEXT)
    	    return;

#if 0
    if ((p->cursor_y == ypos) && (xpos <= p->cursor_x) &&
	(p->cursor_x < (xpos + count))) {
	    cursor_undrawn();
	    redraw_cursor = 1;
    }
#endif

    while (count--) {
	sti_putc(sticon_sti, scr_readw(s++), ypos, xpos++);
    }

    if (redraw_cursor)
	    vbl_cursor_cnt = CURSOR_DRAW_DELAY;
}

static inline void bit_putcs_aligned(struct vc_data *vc, struct fb_info *info,
				     const u16 *s, u32 attr, u32 cnt,
				     u32 d_pitch, u32 s_pitch, u32 cellsize,
				     struct fb_image *image, u8 *buf, u8 *dst)
{
	u16 charmask = vc->vc_hi_font_mask ? 0x1ff : 0xff;
	u32 idx = vc->vc_font.width >> 3;
	u8 *src;

	while (cnt--) {
		src = vc->vc_font.data + (scr_readw(s++)&
					  charmask)*cellsize;

		if (attr) {
			update_attr(buf, src, attr, vc);
			src = buf;
		}

		if (likely(idx == 1))
			__fb_pad_aligned_buffer(dst, d_pitch, src, idx,
						image->height);
		else
			fb_pad_aligned_buffer(dst, d_pitch, src, idx,
					      image->height);

		dst += s_pitch;
	}

	info->fbops->fb_imageblit(info, image);
}

static inline void bit_putcs_unaligned(struct vc_data *vc,
				       struct fb_info *info, const u16 *s,
				       u32 attr, u32 cnt, u32 d_pitch,
				       u32 s_pitch, u32 cellsize,
				       struct fb_image *image, u8 *buf,
				       u8 *dst)
{
	u16 charmask = vc->vc_hi_font_mask ? 0x1ff : 0xff;
	u32 shift_low = 0, mod = vc->vc_font.width % 8;
	u32 shift_high = 8;
	u32 idx = vc->vc_font.width >> 3;
	u8 *src;

	while (cnt--) {
		src = vc->vc_font.data + (scr_readw(s++)&
					  charmask)*cellsize;

		if (attr) {
			update_attr(buf, src, attr, vc);
			src = buf;
		}

		fb_pad_unaligned_buffer(dst, d_pitch, src, idx,
					image->height, shift_high,
					shift_low, mod);
		shift_low += mod;
		dst += (shift_low >= 8) ? s_pitch : s_pitch - 1;
		shift_low &= 7;
		shift_high = 8 - shift_low;
	}

	info->fbops->fb_imageblit(info, image);

}

static unsigned short *
promcon_repaint_line(unsigned short *s, unsigned char *buf, unsigned char **bp)
{
	int cnt = pw + 1;
	int attr = -1;
	unsigned char *b = *bp;

	while (cnt--) {
		u16 c = scr_readw(s);
		if (attr != inverted(c)) {
			attr = inverted(c);
			if (attr) {
				strcpy (b, "\033[7m");
				b += 4;
			} else {
				strcpy (b, "\033[m");
				b += 3;
			}
		}
		*b++ = c;
		s++;
		if (b - buf >= 224) {
			promcon_puts(buf, b - buf);
			b = buf;
		}
	}
	*bp = b;
	return s;
}

static void mdacon_invert_region(struct vc_data *c, u16 *p, int count)
{
	for (; count > 0; count--) {
		scr_writew(scr_readw(p) ^ 0x0800, p);
		p++;
	}
}

static void fbcon_sti_putcs(struct vc_data *conp,
			    struct display *p, 
			    const unsigned short *s,
			    int count, int yy, int xx)
{
	u8 *dest, *dest0, *cdat;
	u_int rows, bold, revs, underl;
	u8 d;
	u16 c;

	if(((unsigned)xx > 200) || ((unsigned) yy > 200)) {
		printk("refusing to putcs %p %p %p %d %d %d (%p)\n",
			conp, p, s, count, yy, xx, __builtin_return_address(0));
		return;
	}	


	dest0 = p->screen_base+yy*fontheight(p)*p->next_line+xx;
	if(((u32)dest0&0xf0000000)!=0xf0000000) {
		printk("refusing to putcs %p %p %p %d %d %d (%p) %p = %p + %d * %d * %ld + %d\n",
			conp, p, s, count, yy, xx, __builtin_return_address(0),
			dest0, p->screen_base, yy, fontheight(p), p->next_line,
			xx);
		return;
	}	

	c = scr_readw(s);
	bold = attr_bold(p, c);
	revs = attr_reverse(p, c);
	underl = attr_underline(p, c);

	while (count--) {
		c = scr_readw(s++) & p->charmask;
		dest = dest0++;
		cdat = p->fontdata+c*fontheight(p);
		for (rows = fontheight(p); rows--; dest += p->next_line) {
			d = *cdat++;
			if (0 && underl && !rows)
				d = 0xff;
			else if (0 && bold)
				d |= d>>1;
			if (revs)
				d = ~d;
			writeb_hp (d, dest);
		}
	}
}

static void mdacon_putcs(struct vc_data *c, const unsigned short *s,
		         int count, int y, int x)
{
	u16 *dest = MDA_ADDR(x, y);

	for (; count > 0; count--) {
		scr_writew(mda_convert_attr(scr_readw(s++)), dest++);
	}
}

static void fbcon_riva32_putcs(struct vc_data *conp, struct display *p,
			     const unsigned short *s, int count, int yy,
			     int xx)
{
	u16 c;
	u32 fgx,bgx;

	xx *= fontwidth(p);
	yy *= fontheight(p);

	c = scr_readw(s);
	fgx = ((u32 *)p->dispsw_data)[attr_fgcol(p, c)];
	bgx = ((u32 *)p->dispsw_data)[attr_bgcol(p, c)];
	while (count--) {
		c = scr_readw(s++);
		fbcon_riva_writechr(conp, p, c, fgx, bgx, yy, xx);
		xx += fontwidth(p);
	}
}

static void fbcon_riva16_putcs(struct vc_data *conp, struct display *p,
			     const unsigned short *s, int count, int yy,
			     int xx)
{
	u16 c;
	u32 fgx,bgx;

	xx *= fontwidth(p);
	yy *= fontheight(p);

	c = scr_readw(s);
	fgx = ((u16 *)p->dispsw_data)[attr_fgcol(p, c)];
	bgx = ((u16 *)p->dispsw_data)[attr_bgcol(p, c)];
	if (p->var.green.length == 6)
		convert_bgcolor_16(&bgx);
	while (count--) {
		c = scr_readw(s++);
		fbcon_riva_writechr(conp, p, c, fgx, bgx, yy, xx);
		xx += fontwidth(p);
	}
}

/* 28.50 in my test */
void fbcon_ega_planes_putcs(struct vc_data *conp, struct display *p, const unsigned short *s,
		   int count, int yy, int xx)
{
	int fg = attr_fgcol(p,scr_readw(s));
	int bg = attr_bgcol(p,scr_readw(s));

	char *where;
	int n;

	setmode(2);
	setop(0);
	selectmask();

	setmask(0xff);
	where = p->screen_base + xx + yy * p->line_length * fontheight(p);
	writeb(bg, where);
	rmb();
	readb(where); /* fill latches */
	wmb();
	selectmask();
	for (n = 0; n < count; n++) {
		int c = scr_readw(s++) & p->charmask;
		u8 *cdat = p->fontdata + c * fontheight(p);
		u8 *end = cdat + fontheight(p);

		while (cdat < end) {
			outb(*cdat++, GRAPHICS_DATA_REG);	
			wmb();
			writeb(fg, where);
			where += p->line_length;
		}
		where += 1 - p->line_length * fontheight(p);
	}
	
	wmb();
}

static void tile_putcs(struct vc_data *vc, struct fb_info *info,
		       const unsigned short *s, int count, int yy, int xx,
		       int fg, int bg)
{
	struct fb_tileblit blit;
	unsigned short charmask = vc->vc_hi_font_mask ? 0x1ff : 0xff;
	int size = sizeof(u32) * count, i;

	blit.sx = xx;
	blit.sy = yy;
	blit.width = count;
	blit.height = 1;
	blit.fg = fg;
	blit.bg = bg;
	blit.length = count;
	blit.indices = (u32 *) fb_get_buffer_offset(info, &info->pixmap, size);
	for (i = 0; i < count; i++)
		blit.indices[i] = (u32)(scr_readw(s++) & charmask);

	info->tileops->fb_tileblit(info, &blit);
}

static void bit_putcs(struct vc_data *vc, struct fb_info *info,
		      const unsigned short *s, int count, int yy, int xx,
		      int fg, int bg)
{
	struct fb_image image;
	u32 width = DIV_ROUND_UP(vc->vc_font.width, 8);
	u32 cellsize = width * vc->vc_font.height;
	u32 maxcnt = info->pixmap.size/cellsize;
	u32 scan_align = info->pixmap.scan_align - 1;
	u32 buf_align = info->pixmap.buf_align - 1;
	u32 mod = vc->vc_font.width % 8, cnt, pitch, size;
	u32 attribute = get_attribute(info, scr_readw(s));
	u8 *dst, *buf = NULL;

	image.fg_color = fg;
	image.bg_color = bg;
	image.dx = xx * vc->vc_font.width;
	image.dy = yy * vc->vc_font.height;
	image.height = vc->vc_font.height;
	image.depth = 1;

	if (attribute) {
		buf = kmalloc(cellsize, GFP_KERNEL);
		if (!buf)
			return;
	}

	while (count) {
		if (count > maxcnt)
			cnt = maxcnt;
		else
			cnt = count;

		image.width = vc->vc_font.width * cnt;
		pitch = DIV_ROUND_UP(image.width, 8) + scan_align;
		pitch &= ~scan_align;
		size = pitch * image.height + buf_align;
		size &= ~buf_align;
		dst = fb_get_buffer_offset(info, &info->pixmap, size);
		image.data = dst;

		if (!mod)
			bit_putcs_aligned(vc, info, s, attribute, cnt, pitch,
					  width, cellsize, &image, buf, dst);
		else
			bit_putcs_unaligned(vc, info, s, attribute, cnt,
					    pitch, width, cellsize, &image,
					    buf, dst);

		image.dx += cnt * vc->vc_font.width;
		count -= cnt;
		s += cnt;
	}

	/* buf is always NULL except when in monochrome mode, so in this case
	   it's a gain to check buf against NULL even though kfree() handles
	   NULL pointers just fine */
	if (unlikely(buf))
		kfree(buf);

}