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/*

 * Copyright (C) 2006 Jakub Vana

 * Copyright (C) 2006 Ondrej Palkovsky

 * All rights reserved.

 *

 * Redistribution and use in source and binary forms, with or without

 * modification, are permitted provided that the following conditions

 * are met:

 *

 * - Redistributions of source code must retain the above copyright

 *   notice, this list of conditions and the following disclaimer.

 * - Redistributions in binary form must reproduce the above copyright

 *   notice, this list of conditions and the following disclaimer in the

 *   documentation and/or other materials provided with the distribution.

 * - The name of the author may not be used to endorse or promote products

 *   derived from this software without specific prior written permission.

 *

 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR

 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES

 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.

 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,

 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT

 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,

 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY

 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT

 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF

 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

 */

#include <stdlib.h>

#include <unistd.h>

#include <string.h>

#include <ddi.h>

#include <sysinfo.h>

#include <align.h>

#include <as.h>

#include <ipc/fb.h>

#include <ipc/ipc.h>

#include <ipc/ns.h>

#include <ipc/services.h>

#include <kernel/errno.h>

#include <async.h>

#include "font-8x16.h"

#include "helenos.xbm"

#include "fb.h"

#include "main.h"

#include "../console/screenbuffer.h"

#include "ppm.h"

#define DEFAULT_BGCOLOR                0x000080

#define DEFAULT_FGCOLOR                0xffff00

/***************************************************************/

/* Pixel specific fuctions */

typedef void (*conv2scr_fn_t)(void *, int);

typedef int (*conv2rgb_fn_t)(void *);

struct {

	__u8 *fbaddress ;

	unsigned int xres ;

	unsigned int yres ;

	unsigned int scanline ;

	unsigned int pixelbytes ;

	conv2scr_fn_t rgb2scr;

	conv2rgb_fn_t scr2rgb;

} screen;

typedef struct {

	int initialized;

	unsigned int x, y;

	unsigned int width, height;

	/* Text support in window */

	unsigned int rows, cols;

	/* Style for text printing */

	style_t style;

	/* Auto-cursor position */

	int cursor_active, cur_col, cur_row;

	int cursor_shown;

} viewport_t;

/** Maximum number of saved pixmaps 

 * Pixmap is a saved rectangle

 */

#define MAX_PIXMAPS        256

typedef struct {

	unsigned int width;

	unsigned int height;

	__u8 *data;

} pixmap_t;

static pixmap_t pixmaps[MAX_PIXMAPS];

/* Viewport is a rectangular area on the screen */

#define MAX_VIEWPORTS 128

static viewport_t viewports[128];

/* Allow only 1 connection */

static int client_connected = 0;

#define RED(x, bits)	((x >> (16 + 8 - bits)) & ((1 << bits) - 1))

#define GREEN(x, bits)	((x >> (8 + 8 - bits)) & ((1 << bits) - 1))

#define BLUE(x, bits)	((x >> (8 - bits)) & ((1 << bits) - 1))

#define COL_WIDTH	8

#define ROW_BYTES	(screen.scanline * FONT_SCANLINES)

#define POINTPOS(x, y)	((y) * screen.scanline + (x) * screen.pixelbytes)

/* Conversion routines between different color representations */

static void rgb_4byte(void *dst, int rgb)

{

	*(int *)dst = rgb;

}

static int byte4_rgb(void *src)

{

	return (*(int *)src) & 0xffffff;

}

static void rgb_3byte(void *dst, int rgb)

{

	__u8 *scr = dst;

#if (defined(BIG_ENDIAN) || defined(FB_BIG_ENDIAN))

	scr[0] = RED(rgb, 8);

	scr[1] = GREEN(rgb, 8);

	scr[2] = BLUE(rgb, 8);

#else

	scr[2] = RED(rgb, 8);

	scr[1] = GREEN(rgb, 8);

	scr[0] = BLUE(rgb, 8);

#endif

}

static int byte3_rgb(void *src)

{

	__u8 *scr = src;

#if (defined(BIG_ENDIAN) || defined(FB_BIG_ENDIAN))

	return scr[0] << 16 | scr[1] << 8 | scr[2];

#else

	return scr[2] << 16 | scr[1] << 8 | scr[0];

#endif	

}

/**  16-bit depth (5:6:5) */

static void rgb_2byte(void *dst, int rgb)

{

	/* 5-bit, 6-bits, 5-bits */ 

	*((__u16 *)(dst)) = RED(rgb, 5) << 11 | GREEN(rgb, 6) << 5 | BLUE(rgb, 5);

}

/** 16-bit depth (5:6:5) */

static int byte2_rgb(void *src)

{

	int color = *(__u16 *)(src);

	return (((color >> 11) & 0x1f) << (16 + 3)) | (((color >> 5) & 0x3f) << (8 + 2)) | ((color & 0x1f) << 3);

}

/** Put pixel - 8-bit depth (3:2:3) */

static void rgb_1byte(void *dst, int rgb)

{

	*(__u8 *)dst = RED(rgb, 3) << 5 | GREEN(rgb, 2) << 3 | BLUE(rgb, 3);

}

/** Return pixel color - 8-bit depth (3:2:3) */

static int byte1_rgb(void *src)

{

	int color = *(__u8 *)src;

	return (((color >> 5) & 0x7) << (16 + 5)) | (((color >> 3) & 0x3) << (8 + 6)) | ((color & 0x7) << 5);

}

/** Put pixel into viewport 

 *

 * @param vp Viewport identification

 * @param x X coord relative to viewport

 * @param y Y coord relative to viewport

 * @param color RGB color 

 */

static void putpixel(int vp, unsigned int x, unsigned int y, int color)

{

	int dx = viewports[vp].x + x;

	int dy = viewports[vp].y + y;

	(*screen.rgb2scr)(&screen.fbaddress[POINTPOS(dx,dy)],color);

}

/** Get pixel from viewport */

static int getpixel(int vp, unsigned int x, unsigned int y)

{

	int dx = viewports[vp].x + x;

	int dy = viewports[vp].y + y;

	return (*screen.scr2rgb)(&screen.fbaddress[POINTPOS(dx,dy)]);

}

/** Fill line with color BGCOLOR */

static void clear_line(int vp, unsigned int y)

{

	unsigned int x;

	for (x = 0; x < viewports[vp].width; x++)

		putpixel(vp, x, y, viewports[vp].style.bg_color);

}

static void draw_rectangle(int vp, unsigned int sx, unsigned int sy,

			   unsigned int width, unsigned int height,

			   int color)

{

	unsigned int x, y;

	/* Clear first line */

	for (x = 0; x < width; x++)

		putpixel(vp, sx + x, sy, color);

	/* Recompute to screen coords */

	sx += viewports[vp].x;

	sy += viewports[vp].y;

	/* Copy the rest */

	for (y = sy+1;y < sy+height; y++)

		memcpy(&screen.fbaddress[POINTPOS(sx,y)],

		       &screen.fbaddress[POINTPOS(sx,sy)],

		       screen.pixelbytes * width);

}

/** Fill viewport with background color */

static void clear_port(int vp)

{

	viewport_t *vport = &viewports[vp];

	draw_rectangle(vp, 0, 0, vport->width, vport->height, vport->style.bg_color);

}

/** Scroll port up/down 

 *

 * @param vp Viewport to scroll

 * @param rows Positive number - scroll up, negative - scroll down

 */

static void scroll_port(int vp, int rows)

{

	int y;

	int startline;

	int endline;

	viewport_t *vport = &viewports[vp];

	if (rows > 0) {

		for (y=vport->y; y < vport->y+vport->height - rows*FONT_SCANLINES; y++)

			memcpy(&screen.fbaddress[POINTPOS(vport->x,y)],

			       &screen.fbaddress[POINTPOS(vport->x,y + rows*FONT_SCANLINES)],

			       screen.pixelbytes * vport->width);

		draw_rectangle(vp, 0, FONT_SCANLINES*(vport->rows - 1),

			       vport->width, FONT_SCANLINES, vport->style.bg_color);

	} else if (rows < 0) {

		rows = -rows;

		for (y=vport->y + vport->height-1; y >= vport->y + rows*FONT_SCANLINES; y--)

			memcpy(&screen.fbaddress[POINTPOS(vport->x,y)],

				&screen.fbaddress[POINTPOS(vport->x,y - rows*FONT_SCANLINES)],

				screen.pixelbytes * vport->width);

		draw_rectangle(vp, 0, 0, vport->width, FONT_SCANLINES, vport->style.bg_color);

	}

}

static void invert_pixel(int vp,unsigned int x, unsigned int y)

{

	putpixel(vp, x, y, ~getpixel(vp, x, y));

}

/***************************************************************/

/* Character-console functions */

/** Draw character at given position

 *

 * @param vp Viewport where the character is printed

 * @param sx Coordinates of top-left of the character

 * @param sy Coordinates of top-left of the character

 * @param style Color of the character

 * @param transparent If false, print background color

 */

static void draw_glyph(int vp,__u8 glyph, unsigned int sx, unsigned int sy, 

		       style_t style, int transparent)

{

	int i;

	unsigned int y;

	unsigned int glline;

	for (y = 0; y < FONT_SCANLINES; y++) {

		glline = fb_font[glyph * FONT_SCANLINES + y];

		for (i = 0; i < 8; i++) {

			if (glline & (1 << (7 - i)))

				putpixel(vp, sx + i, sy + y, style.fg_color);

			else if (!transparent)

				putpixel(vp, sx + i, sy + y, style.bg_color);

		}

	}

}

/** Invert character at given position */

static void invert_char(int vp,unsigned int row, unsigned int col)

{

	unsigned int x;

	unsigned int y;

	for (x = 0; x < COL_WIDTH; x++)

		for (y = 0; y < FONT_SCANLINES; y++)

			invert_pixel(vp, col * COL_WIDTH + x, row * FONT_SCANLINES + y);

}

/***************************************************************/

/* Stdout specific functions */

/** Create new viewport

 *

 * @return New viewport number

 */

static int viewport_create(unsigned int x, unsigned int y,unsigned int width, 

			   unsigned int height)

{

	int i;

for (i=0; i < MAX_VIEWPORTS; i++) {

		if (!viewports[i].initialized)

			break;

	}

	if (i == MAX_VIEWPORTS)

		return ELIMIT;

	if (width ==0 || height == 0 ||

	    x+width > screen.xres || y+height > screen.yres)

		return EINVAL;

	if (width < FONT_SCANLINES || height < COL_WIDTH)

		return EINVAL;

	viewports[i].x = x;

	viewports[i].y = y;

	viewports[i].width = width;

	viewports[i].height = height;

	viewports[i].rows = height / FONT_SCANLINES;

	viewports[i].cols = width / COL_WIDTH;

	viewports[i].style.bg_color = DEFAULT_BGCOLOR;

	viewports[i].style.fg_color = DEFAULT_FGCOLOR;

	viewports[i].cur_col = 0;

	viewports[i].cur_row = 0;

	viewports[i].cursor_active = 0;

	viewports[i].initialized = 1;

	return i;

}

/** Initialize framebuffer as a chardev output device

 *

 * @param addr Address of theframebuffer

 * @param x    Screen width in pixels

 * @param y    Screen height in pixels

 * @param bpp  Bits per pixel (8, 16, 24, 32)

 * @param scan Bytes per one scanline

 *

 */

static void screen_init(void *addr, unsigned int xres, unsigned int yres, unsigned int bpp, unsigned int scan)

{

	switch (bpp) {

		case 8:

			screen.rgb2scr = rgb_1byte;

			screen.scr2rgb = byte1_rgb;

			screen.pixelbytes = 1;

			break;

		case 16:

			screen.rgb2scr = rgb_2byte;

			screen.scr2rgb = byte2_rgb;

			screen.pixelbytes = 2;

			break;

		case 24:

			screen.rgb2scr = rgb_3byte;

			screen.scr2rgb = byte3_rgb;

			screen.pixelbytes = 3;

			break;

		case 32:

			screen.rgb2scr = rgb_4byte;

			screen.scr2rgb = byte4_rgb;

			screen.pixelbytes = 4;

			break;

	}

	screen.fbaddress = (unsigned char *) addr;

	screen.xres = xres;

	screen.yres = yres;

	screen.scanline = scan;

	/* Create first viewport */

	viewport_create(0,0,xres,yres);

}

/** Hide cursor if it is shown */

static void cursor_hide(int vp)

{

	viewport_t *vport = &viewports[vp];

	if (vport->cursor_active && vport->cursor_shown) {

		invert_char(vp, vport->cur_row, vport->cur_col);

		vport->cursor_shown = 0;

	}

}

/** Show cursor if cursor showing is enabled */

static void cursor_print(int vp)

{

	viewport_t *vport = &viewports[vp];

	/* Do not check for cursor_shown */

	if (vport->cursor_active) {

		invert_char(vp, vport->cur_row, vport->cur_col);

		vport->cursor_shown = 1;

	}

}

/** Invert cursor, if it is enabled */

static void cursor_blink(int vp)

{

	viewport_t *vport = &viewports[vp];

	if (vport->cursor_shown)

		cursor_hide(vp);

	else

		cursor_print(vp);

}

/** Draw character at given position relative to viewport 

 * 

 * @param vp Viewport identification

 * @param c Character to print

 * @param row Screen position relative to viewport

 * @param col Screen position relative to viewport

 * @param transparent If false, print background color with character

 */

static void draw_char(int vp, char c, unsigned int row, unsigned int col, style_t style, int transparent)

{

	viewport_t *vport = &viewports[vp];

	/* Optimize - do not hide cursor if we are going to overwrite it */

	if (vport->cursor_active && vport->cursor_shown && 

	    (vport->cur_col != col || vport->cur_row != row))

		invert_char(vp, vport->cur_row, vport->cur_col);

	draw_glyph(vp, c, col * COL_WIDTH, row * FONT_SCANLINES, style, transparent);

	vport->cur_col = col;

	vport->cur_row = row;

	vport->cur_col++;

	if (vport->cur_col>= vport->cols) {

		vport->cur_col = 0;

		vport->cur_row++;

		if (vport->cur_row >= vport->rows)

			vport->cur_row--;

	}

	cursor_print(vp);

}

/** Draw text data to viewport

 *

 * @param vp Viewport id

 * @param data Text data fitting exactly into viewport

 */

static void draw_text_data(int vp, keyfield_t *data)

{

	viewport_t *vport = &viewports[vp];

	int i;

	char c;

	int col,row;

	clear_port(vp);

	for (i=0; i < vport->cols * vport->rows; i++) {

		if (data[i].character == ' ' && style_same(data[i].style,vport->style))

			continue;

		col = i % vport->cols;

		row = i / vport->cols;

		draw_glyph(vp, data[i].character, col * COL_WIDTH, row * FONT_SCANLINES, 

			   data[i].style, style_same(data[i].style,vport->style));

	}

	cursor_print(vp);

}

/** Return first free pixmap */

static int find_free_pixmap(void)

{

	int i;

	for (i=0;i < MAX_PIXMAPS;i++)

		if (!pixmaps[i].data)

			return i;

	return -1;

}

static void putpixel_pixmap(int pm, unsigned int x, unsigned int y, int color)

{

	pixmap_t *pmap = &pixmaps[pm];

	int pos = (y * pmap->width + x) * screen.pixelbytes;

	(*screen.rgb2scr)(&pmap->data[pos],color);

}

/** Create a new pixmap and return appropriate ID */

static int shm2pixmap(char *shm, size_t size)

{

	int pm;

	pixmap_t *pmap;

	pm = find_free_pixmap();

	if (pm == -1)

		return ELIMIT;

	pmap = &pixmaps[pm];

	if (ppm_get_data(shm, size, &pmap->width, &pmap->height))

		return EINVAL;

	pmap->data = malloc(pmap->width * pmap->height * screen.pixelbytes);

	if (!pmap->data)

		return ENOMEM;

	ppm_draw(shm, size, 0, 0, pmap->width, pmap->height, 

		 putpixel_pixmap, pm);

	return pm;

}

/** Handle shared memory communication calls

 *

 * Protocol for drawing pixmaps:

 * - FB_PREPARE_SHM(client shm identification)

 * - IPC_M_SEND_AS_AREA

 * - FB_DRAW_PPM(startx,starty)

 * - FB_DROP_SHM

 *

 * Protocol for text drawing

 * - IPC_M_SEND_AS_AREA

 * - FB_DRAW_TEXT_DATA

 *

 * @param callid Callid of the current call

 * @param call Current call data

 * @param vp Active viewport

 * @return 0 if the call was not handled byt this function, 1 otherwise

 *

 * note: this function is not threads safe, you would have

 * to redefine static variables with __thread

 */

static int shm_handle(ipc_callid_t callid, ipc_call_t *call, int vp)

{

	static keyfield_t *interbuffer = NULL;

	static size_t intersize = 0;

	static char *shm = NULL;

	static ipcarg_t shm_id = 0;

	static size_t shm_size;

	int handled = 1;

	int retval = 0;

	viewport_t *vport = &viewports[vp];

	unsigned int x,y;

	switch (IPC_GET_METHOD(*call)) {

	case IPC_M_AS_AREA_SEND:

		/* We accept one area for data interchange */

		if (IPC_GET_ARG1(*call) == shm_id) {

			void *dest = as_get_mappable_page(IPC_GET_ARG2(*call));

			shm_size = IPC_GET_ARG2(*call);

			if (!ipc_answer_fast(callid, 0, (sysarg_t)dest, 0)) 

				shm = dest;

			else

				shm_id = 0;

			if (shm[0] != 'P')

				while (1)

					;

			return 1;

		} else {

			intersize = IPC_GET_ARG2(*call);

			receive_comm_area(callid,call,(void **)&interbuffer);

		}

		return 1;

	case FB_PREPARE_SHM:

		if (shm_id)

			retval = EBUSY;

		else 

			shm_id = IPC_GET_ARG1(*call);

		break;

	case FB_DROP_SHM:

		if (shm) {

			as_area_destroy(shm);

			shm = NULL;

		}

		shm_id = 0;

		break;

	case FB_SHM2PIXMAP:

		if (!shm) {

			retval = EINVAL;

			break;

		}

		retval = shm2pixmap(shm, shm_size);

		break;

	case FB_DRAW_PPM:

		if (!shm) {

			retval = EINVAL;

			break;

		}

		x = IPC_GET_ARG1(*call);

		y = IPC_GET_ARG2(*call);

		if (x > vport->width || y > vport->height) {

			retval = EINVAL;

			break;

		}

		ppm_draw(shm, shm_size, IPC_GET_ARG1(*call), IPC_GET_ARG2(*call),

			 vport->width - x, vport->height - y, putpixel, vp);

		break;

	case FB_DRAW_TEXT_DATA:

		if (!interbuffer) {

			retval = EINVAL;

			break;

		}

		if (intersize < vport->cols*vport->rows*sizeof(*interbuffer)) {

			retval = EINVAL;

			break;

		}

		draw_text_data(vp, interbuffer);

		break;

	default:

		handled = 0;

	}

	if (handled)

		ipc_answer_fast(callid, retval, 0, 0);

	return handled;

}

/** Save viewport to pixmap */

static int save_vp_to_pixmap(int vp)

{

	int pm;

	pixmap_t *pmap;

	viewport_t *vport = &viewports[vp];

	int x,y;

	int rowsize;

	int tmp;

	pm = find_free_pixmap();

	if (pm == -1)

		return ELIMIT;

	pmap = &pixmaps[pm];

	pmap->data = malloc(screen.pixelbytes * vport->width * vport->height);

	if (!pmap->data)

		return ENOMEM;

	pmap->width = vport->width;

	pmap->height = vport->height;

	rowsize = vport->width * screen.pixelbytes;

	for (y=0;y < vport->height; y++) {

		tmp = (vport->y + y) * screen.scanline + vport->x * screen.pixelbytes;

		memcpy(pmap->data + rowsize*y, screen.fbaddress + tmp, rowsize); 

	}

	return pm;

}

/** Draw pixmap on screen

 *

 * @param vp Viewport to draw on

 * @param pm Pixmap identifier

 */

static int draw_pixmap(int vp, int pm)

{

	pixmap_t *pmap = &pixmaps[pm];

	viewport_t *vport = &viewports[vp];

	int x,y;

	int tmp, srcrowsize;

	int realwidth, realheight, realrowsize;

	if (!pmap->data)

		return EINVAL;

	realwidth = pmap->width <= vport->width ? pmap->width : vport->width;

	realheight = pmap->height <= vport->height ? pmap->height : vport->height;

	srcrowsize = vport->width * screen.pixelbytes;

	realrowsize = realwidth * screen.pixelbytes;

	for (y=0; y < realheight; y++) {

		tmp = (vport->y + y) * screen.scanline + vport->x * screen.pixelbytes;

		memcpy(screen.fbaddress + tmp, pmap->data + y * srcrowsize, realrowsize);

	}

	return 0;

}

/** Handler for messages concerning pixmap handling */

static int pixmap_handle(ipc_callid_t callid, ipc_call_t *call, int vp)

{

	int handled = 1;

	int retval = 0;

	int i,nvp;

	switch (IPC_GET_METHOD(*call)) {

	case FB_VP_DRAW_PIXMAP:

		nvp = IPC_GET_ARG1(*call);

		if (nvp == -1)

			nvp = vp;

		if (nvp < 0 || nvp >= MAX_VIEWPORTS || !viewports[nvp].initialized) {

			retval = EINVAL;

			break;

		}

		i = IPC_GET_ARG2(*call);

		retval = draw_pixmap(nvp, i);

		break;

	case FB_VP2PIXMAP:

		nvp = IPC_GET_ARG1(*call);

		if (nvp == -1)

			nvp = vp;

		if (nvp < 0 || nvp >= MAX_VIEWPORTS || !viewports[nvp].initialized)

			retval = EINVAL;

		else

			retval = save_vp_to_pixmap(nvp);

		break;

	case FB_DROP_PIXMAP:

		i = IPC_GET_ARG1(*call);

		if (i >= MAX_PIXMAPS) {

			retval = EINVAL;

			break;

		}

		if (pixmaps[i].data) {

			free(pixmaps[i].data);

			pixmaps[i].data = NULL;

		}

		break;

	default:

		handled = 0;

	}

	if (handled)

		ipc_answer_fast(callid, retval, 0, 0);

	return handled;

}

/** Function for handling connections to FB

 *

 */

static void fb_client_connection(ipc_callid_t iid, ipc_call_t *icall)

{

	ipc_callid_t callid;

	ipc_call_t call;

	int retval;

	int i;

	unsigned int row,col;

	char c;

	int vp = 0;

	viewport_t *vport = &viewports[0];

	if (client_connected) {

		ipc_answer_fast(iid, ELIMIT, 0,0);

		return;

	}

	client_connected = 1;

	ipc_answer_fast(iid, 0, 0, 0); /* Accept connection */

	while (1) {

		callid = async_get_call_timeout(&call,250000);

		if (!callid) {

			cursor_blink(vp);

			continue;

		}

		if (shm_handle(callid, &call, vp))

			continue;

		if (pixmap_handle(callid, &call, vp))

			continue;

 		switch (IPC_GET_METHOD(call)) {

		case IPC_M_PHONE_HUNGUP:

			client_connected = 0;

			/* cleanup other viewports */

			for (i=1; i < MAX_VIEWPORTS; i++)

				vport->initialized = 0;

			ipc_answer_fast(callid,0,0,0);

			return; /* Exit thread */

		case FB_PUTCHAR:

		case FB_TRANS_PUTCHAR:

			c = IPC_GET_ARG1(call);

			row = IPC_GET_ARG2(call);

			col = IPC_GET_ARG3(call);

			if (row >= vport->rows || col >= vport->cols) {

				retval = EINVAL;

				break;

			}

			ipc_answer_fast(callid,0,0,0);

			draw_char(vp, c, row, col, vport->style, IPC_GET_METHOD(call) == FB_TRANS_PUTCHAR);

			continue; /* msg already answered */

		case FB_CLEAR:

			clear_port(vp);

			cursor_print(vp);

			retval = 0;

			break;

 		case FB_CURSOR_GOTO:

			row = IPC_GET_ARG1(call);

			col = IPC_GET_ARG2(call);

			if (row >= vport->rows || col >= vport->cols) {

				retval = EINVAL;

				break;

			}

 			retval = 0;

			cursor_hide(vp);

			vport->cur_col = col;

			vport->cur_row = row;

			cursor_print(vp);

 			break;

		case FB_CURSOR_VISIBILITY:

			cursor_hide(vp);

			vport->cursor_active = IPC_GET_ARG1(call);

			cursor_print(vp);

			retval = 0;

			break;

		case FB_GET_CSIZE:

			ipc_answer_fast(callid, 0, vport->rows, vport->cols);

			continue;

		case FB_SCROLL:

			i = IPC_GET_ARG1(call);

			if (i > vport->rows || i < (- (int)vport->rows)) {

				retval = EINVAL;

				break;

			}

			cursor_hide(vp);

			scroll_port(vp, i);

			cursor_print(vp);

			retval = 0;

			break;

		case FB_VIEWPORT_SWITCH:

			i = IPC_GET_ARG1(call);

			if (i < 0 || i >= MAX_VIEWPORTS) {

				retval = EINVAL;

				break;

			}

			if (! viewports[i].initialized ) {

				retval = EADDRNOTAVAIL;

				break;

			}

			cursor_hide(vp);

			vp = i;

			vport = &viewports[vp];

			cursor_print(vp);

			retval = 0;

			break;

		case FB_VIEWPORT_CREATE:

			retval = viewport_create(IPC_GET_ARG1(call) >> 16,

						 IPC_GET_ARG1(call) & 0xffff,

						 IPC_GET_ARG2(call) >> 16,

						 IPC_GET_ARG2(call) & 0xffff);

			break;

		case FB_VIEWPORT_DELETE:

			i = IPC_GET_ARG1(call);

			if (i < 0 || i >= MAX_VIEWPORTS) {

				retval = EINVAL;

				break;

			}

			if (! viewports[i].initialized ) {

				retval = EADDRNOTAVAIL;

				break;

			}

			viewports[i].initialized = 0;

			retval = 0;

			break;

		case FB_SET_STYLE:

			vport->style.fg_color = IPC_GET_ARG1(call);

			vport->style.bg_color = IPC_GET_ARG2(call);

			retval = 0;

			break;

		case FB_GET_RESOLUTION:

			ipc_answer_fast(callid, 0, screen.xres,screen.yres);

			continue;

		default:

			retval = ENOENT;

		}

		ipc_answer_fast(callid,retval,0,0);

	}

}

/** Initialization of framebuffer */

int fb_init(void)

{

	void *fb_ph_addr;

	unsigned int fb_width;

	unsigned int fb_height;

	unsigned int fb_bpp;

	unsigned int fb_scanline;

	void *fb_addr;

	size_t asz;

	async_set_client_connection(fb_client_connection);

	fb_ph_addr=(void *)sysinfo_value("fb.address.physical");

	fb_width=sysinfo_value("fb.width");

	fb_height=sysinfo_value("fb.height");

	fb_bpp=sysinfo_value("fb.bpp");

	fb_scanline=sysinfo_value("fb.scanline");

	asz = fb_scanline*fb_height;

	fb_addr = as_get_mappable_page(asz);

	map_physmem(fb_ph_addr, fb_addr, ALIGN_UP(asz,PAGE_SIZE) >>PAGE_WIDTH,

		    AS_AREA_READ | AS_AREA_WRITE | AS_AREA_CACHEABLE);

	screen_init(fb_addr, fb_width, fb_height, fb_bpp, fb_scanline);

	return 0;

}