[PATCH v2 2/6] video: console: Parse UTF-8 character sequences

Heinrich Schuchardt xypron.glpk at gmx.de
Mon Feb 12 13:12:00 CET 2024


On 10.02.24 13:46, Janne Grunau via B4 Relay wrote:
> From: Janne Grunau <j at jannau.net>
>
> efi_console / UEFI applications (grub2, sd-boot, ...) pass UTF-8
> character sequences to vidconsole which results in wrong glyphs for code
> points outside of ASCII. The truetype console expects Unicode code
> points and bitmap font based consoles expect code page 437 code points.
> To support both convert UTF-8 to UTF-32 and pass Unicode code points in
> vidconsole_ops.putc_xy(). These can be used directly in console_truetype
> and after conversion to code page 437 in console_{normal,rotate}.
>
> This fixes rendering of international, symbol and box drawing characters
> used by UEFI applications.
>
> Signed-off-by: Janne Grunau <j at jannau.net>
> ---
>   drivers/video/console_normal.c      |  6 ++++--
>   drivers/video/console_rotate.c      | 16 ++++++++++------
>   drivers/video/console_truetype.c    |  8 ++++----
>   drivers/video/vidconsole-uclass.c   | 18 +++++++++++++-----
>   drivers/video/vidconsole_internal.h | 15 +++++++++++++++
>   include/video_console.h             | 10 ++++++----
>   6 files changed, 52 insertions(+), 21 deletions(-)
>
> diff --git a/drivers/video/console_normal.c b/drivers/video/console_normal.c
> index a0231293f3..34ef5a5229 100644
> --- a/drivers/video/console_normal.c
> +++ b/drivers/video/console_normal.c
> @@ -7,6 +7,7 @@
>    */
>
>   #include <common.h>
> +#include <charset.h>
>   #include <dm.h>
>   #include <video.h>
>   #include <video_console.h>
> @@ -63,7 +64,7 @@ static int console_move_rows(struct udevice *dev, uint rowdst,
>   	return 0;
>   }
>
> -static int console_putc_xy(struct udevice *dev, uint x_frac, uint y, char ch)
> +static int console_putc_xy(struct udevice *dev, uint x_frac, uint y, int cp)
>   {
>   	struct vidconsole_priv *vc_priv = dev_get_uclass_priv(dev);
>   	struct udevice *vid = dev->parent;
> @@ -73,8 +74,9 @@ static int console_putc_xy(struct udevice *dev, uint x_frac, uint y, char ch)
>   	int pbytes = VNBYTES(vid_priv->bpix);
>   	int x, linenum, ret;
>   	void *start, *line;
> +	u8 ch = console_utf_to_cp437(cp);
>   	uchar *pfont = fontdata->video_fontdata +
> -			(u8)ch * fontdata->char_pixel_bytes;
> +			ch * fontdata->char_pixel_bytes;
>
>   	if (x_frac + VID_TO_POS(vc_priv->x_charsize) > vc_priv->xsize_frac)
>   		return -EAGAIN;
> diff --git a/drivers/video/console_rotate.c b/drivers/video/console_rotate.c
> index 65358a1c6e..e4303dfb36 100644
> --- a/drivers/video/console_rotate.c
> +++ b/drivers/video/console_rotate.c
> @@ -7,6 +7,7 @@
>    */
>
>   #include <common.h>
> +#include <charset.h>
>   #include <dm.h>
>   #include <video.h>
>   #include <video_console.h>
> @@ -67,7 +68,7 @@ static int console_move_rows_1(struct udevice *dev, uint rowdst, uint rowsrc,
>   	return 0;
>   }
>
> -static int console_putc_xy_1(struct udevice *dev, uint x_frac, uint y, char ch)
> +static int console_putc_xy_1(struct udevice *dev, uint x_frac, uint y, int cp)
>   {
>   	struct vidconsole_priv *vc_priv = dev_get_uclass_priv(dev);
>   	struct udevice *vid = dev->parent;
> @@ -77,8 +78,9 @@ static int console_putc_xy_1(struct udevice *dev, uint x_frac, uint y, char ch)
>   	int pbytes = VNBYTES(vid_priv->bpix);
>   	int x, linenum, ret;
>   	void *start, *line;
> +	u8 ch = console_utf_to_cp437(cp);
>   	uchar *pfont = fontdata->video_fontdata +
> -			(u8)ch * fontdata->char_pixel_bytes;
> +			ch * fontdata->char_pixel_bytes;
>
>   	if (x_frac + VID_TO_POS(vc_priv->x_charsize) > vc_priv->xsize_frac)
>   		return -EAGAIN;
> @@ -145,7 +147,7 @@ static int console_move_rows_2(struct udevice *dev, uint rowdst, uint rowsrc,
>   	return 0;
>   }
>
> -static int console_putc_xy_2(struct udevice *dev, uint x_frac, uint y, char ch)
> +static int console_putc_xy_2(struct udevice *dev, uint x_frac, uint y, int cp)
>   {
>   	struct vidconsole_priv *vc_priv = dev_get_uclass_priv(dev);
>   	struct udevice *vid = dev->parent;
> @@ -155,8 +157,9 @@ static int console_putc_xy_2(struct udevice *dev, uint x_frac, uint y, char ch)
>   	int pbytes = VNBYTES(vid_priv->bpix);
>   	int linenum, x, ret;
>   	void *start, *line;
> +	u8 ch = console_utf_to_cp437(cp);
>   	uchar *pfont = fontdata->video_fontdata +
> -			(u8)ch * fontdata->char_pixel_bytes;
> +			ch * fontdata->char_pixel_bytes;
>
>   	if (x_frac + VID_TO_POS(vc_priv->x_charsize) > vc_priv->xsize_frac)
>   		return -EAGAIN;
> @@ -227,7 +230,7 @@ static int console_move_rows_3(struct udevice *dev, uint rowdst, uint rowsrc,
>   	return 0;
>   }
>
> -static int console_putc_xy_3(struct udevice *dev, uint x_frac, uint y, char ch)
> +static int console_putc_xy_3(struct udevice *dev, uint x_frac, uint y, int cp)
>   {
>   	struct vidconsole_priv *vc_priv = dev_get_uclass_priv(dev);
>   	struct udevice *vid = dev->parent;
> @@ -237,8 +240,9 @@ static int console_putc_xy_3(struct udevice *dev, uint x_frac, uint y, char ch)
>   	int pbytes = VNBYTES(vid_priv->bpix);
>   	int linenum, x, ret;
>   	void *start, *line;
> +	u8 ch = console_utf_to_cp437(cp);
>   	uchar *pfont = fontdata->video_fontdata +
> -			(u8)ch * fontdata->char_pixel_bytes;
> +			ch * fontdata->char_pixel_bytes;
>
>   	if (x_frac + VID_TO_POS(vc_priv->x_charsize) > vc_priv->xsize_frac)
>   		return -EAGAIN;
> diff --git a/drivers/video/console_truetype.c b/drivers/video/console_truetype.c
> index 14fb81e956..bc3ec1c31f 100644
> --- a/drivers/video/console_truetype.c
> +++ b/drivers/video/console_truetype.c
> @@ -262,7 +262,7 @@ static int console_truetype_move_rows(struct udevice *dev, uint rowdst,
>   }
>
>   static int console_truetype_putc_xy(struct udevice *dev, uint x, uint y,
> -				    char ch)
> +				    int cp)
>   {
>   	struct vidconsole_priv *vc_priv = dev_get_uclass_priv(dev);
>   	struct udevice *vid = dev->parent;
> @@ -281,7 +281,7 @@ static int console_truetype_putc_xy(struct udevice *dev, uint x, uint y,
>   	int row, ret;
>
>   	/* First get some basic metrics about this character */
> -	stbtt_GetCodepointHMetrics(font, ch, &advance, &lsb);
> +	stbtt_GetCodepointHMetrics(font, cp, &advance, &lsb);
>
>   	/*
>   	 * First out our current X position in fractional pixels. If we wrote
> @@ -290,7 +290,7 @@ static int console_truetype_putc_xy(struct udevice *dev, uint x, uint y,
>   	xpos = frac(VID_TO_PIXEL((double)x));
>   	if (vc_priv->last_ch) {
>   		xpos += met->scale * stbtt_GetCodepointKernAdvance(font,
> -							vc_priv->last_ch, ch);
> +							vc_priv->last_ch, cp);
>   	}
>
>   	/*
> @@ -320,7 +320,7 @@ static int console_truetype_putc_xy(struct udevice *dev, uint x, uint y,
>   	 * return NULL;
>   	 */
>   	data = stbtt_GetCodepointBitmapSubpixel(font, met->scale, met->scale,
> -						x_shift, 0, ch, &width, &height,
> +						x_shift, 0, cp, &width, &height,
>   						&xoff, &yoff);
>   	if (!data)
>   		return width_frac;
> diff --git a/drivers/video/vidconsole-uclass.c b/drivers/video/vidconsole-uclass.c
> index 22d55df71f..5f89f6a521 100644
> --- a/drivers/video/vidconsole-uclass.c
> +++ b/drivers/video/vidconsole-uclass.c
> @@ -11,6 +11,7 @@
>
>   #include <common.h>
>   #include <abuf.h>
> +#include <charset.h>
>   #include <command.h>
>   #include <console.h>
>   #include <log.h>
> @@ -20,7 +21,7 @@
>   #include <video_font.h>		/* Bitmap font for code page 437 */
>   #include <linux/ctype.h>
>
> -int vidconsole_putc_xy(struct udevice *dev, uint x, uint y, char ch)
> +int vidconsole_putc_xy(struct udevice *dev, uint x, uint y, int ch)
>   {
>   	struct vidconsole_ops *ops = vidconsole_get_ops(dev);
>
> @@ -426,8 +427,8 @@ error:
>   	priv->escape = 0;
>   }
>
> -/* Put that actual character on the screen (using the CP437 code page). */
> -static int vidconsole_output_glyph(struct udevice *dev, char ch)
> +/* Put that actual character on the screen (using the UTF-32 code points). */
> +static int vidconsole_output_glyph(struct udevice *dev, int ch)
>   {
>   	struct vidconsole_priv *priv = dev_get_uclass_priv(dev);
>   	int ret;
> @@ -455,7 +456,7 @@ static int vidconsole_output_glyph(struct udevice *dev, char ch)
>   int vidconsole_put_char(struct udevice *dev, char ch)
>   {
>   	struct vidconsole_priv *priv = dev_get_uclass_priv(dev);
> -	int ret;
> +	int cp, ret;
>
>   	if (priv->escape) {
>   		vidconsole_escape_char(dev, ch);
> @@ -489,7 +490,14 @@ int vidconsole_put_char(struct udevice *dev, char ch)
>   		priv->last_ch = 0;
>   		break;
>   	default:
> -		ret = vidconsole_output_glyph(dev, ch);
> +		if (CONFIG_IS_ENABLED(CHARSET)) {
> +			cp = utf8_to_utf32_stream(ch, priv->utf8_buf);
> +			if (cp == 0)
> +				return 0;
> +		} else {
> +			cp = ch;
> +		}
> +		ret = vidconsole_output_glyph(dev, cp);
>   		if (ret < 0)
>   			return ret;
>   		break;
> diff --git a/drivers/video/vidconsole_internal.h b/drivers/video/vidconsole_internal.h
> index 0ec581b266..5dae7f85ad 100644
> --- a/drivers/video/vidconsole_internal.h
> +++ b/drivers/video/vidconsole_internal.h
> @@ -6,6 +6,9 @@
>    * (C) Copyright 2023 Dzmitry Sankouski <dsankouski at gmail.com>
>    */
>
> +#include <charset.h>
> +#include <config.h>
> +
>   #define FLIPPED_DIRECTION 1
>   #define NORMAL_DIRECTION 0
>
> @@ -142,3 +145,15 @@ int console_simple_get_font(struct udevice *dev, int seq, struct vidfont_info *i
>    * See details in video_console.h select_font function
>    **/
>   int console_simple_select_font(struct udevice *dev, const char *name, uint size);
> +
> +/**
> + *
> + */
> +static inline u8 console_utf_to_cp437(int codepoint)
> +{
> +	if (CONFIG_IS_ENABLED(CHARSET)) {
> +		utf_to_cp(&codepoint, codepage_437);
> +		return (u8)codepoint;

The (u8) conversion is superfluous in C.

> +	}
> +	return (u8)codepoint;
> +}
> diff --git a/include/video_console.h b/include/video_console.h
> index bde67fa9a5..20cf2d0101 100644
> --- a/include/video_console.h
> +++ b/include/video_console.h
> @@ -43,6 +43,7 @@ enum {
>    * @col_saved:		Saved X position, in fractional units (VID_TO_POS(x))
>    * @row_saved:		Saved Y position in pixels (0=top)
>    * @escape_buf:		Buffer to accumulate escape sequence
> + * @utf8_buf:		Buffer to accumulate UTF-8 byte sequence
>    */
>   struct vidconsole_priv {
>   	struct stdio_dev sdev;
> @@ -66,6 +67,7 @@ struct vidconsole_priv {
>   	int row_saved;
>   	int col_saved;
>   	char escape_buf[32];
> +	char utf8_buf[8];

In patch 1 you described that 5 bytes are enough.

Best regards

Heinrich

>   };
>
>   /**
> @@ -124,12 +126,12 @@ struct vidconsole_ops {
>   	 * @x_frac:	Fractional pixel X position (0=left-most pixel) which
>   	 *		is the X position multipled by VID_FRAC_DIV.
>   	 * @y:		Pixel Y position (0=top-most pixel)
> -	 * @ch:		Character to write
> +	 * @cp:		UTF-32 code point to write
>   	 * @return number of fractional pixels that the cursor should move,
>   	 * if all is OK, -EAGAIN if we ran out of space on this line, other -ve
>   	 * on error
>   	 */
> -	int (*putc_xy)(struct udevice *dev, uint x_frac, uint y, char ch);
> +	int (*putc_xy)(struct udevice *dev, uint x_frac, uint y, int cp);
>
>   	/**
>   	 * move_rows() - Move text rows from one place to another
> @@ -403,12 +405,12 @@ void vidconsole_pop_colour(struct udevice *dev, struct vidconsole_colour *old);
>    * @x_frac:	Fractional pixel X position (0=left-most pixel) which
>    *		is the X position multipled by VID_FRAC_DIV.
>    * @y:		Pixel Y position (0=top-most pixel)
> - * @ch:		Character to write
> + * @cp:		UTF-32 code point to write
>    * Return: number of fractional pixels that the cursor should move,
>    * if all is OK, -EAGAIN if we ran out of space on this line, other -ve
>    * on error
>    */
> -int vidconsole_putc_xy(struct udevice *dev, uint x, uint y, char ch);
> +int vidconsole_putc_xy(struct udevice *dev, uint x, uint y, int cp);
>
>   /**
>    * vidconsole_move_rows() - Move text rows from one place to another
>



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