Re: [PATCH] Fix console utf8 composing

["Alexander E. Patrakov" <patrakov@ums.usu.ru>]

Jan Engelhardt wrote:
> Hi,
> 
> 
> the following patch had been posted around spring 2005, but has not since 
> been included. It is about that hitting the keys <Compose><o><e> for example
> did not produce the utf8 sequence for o-with-diaeresis, but the ASCII/ISO8859-1
> char for o-w-diaeresis, as I seem to recall.
> http://groups.google.de/group/linux.kernel/browse_thread/thread/e60f286969e83d99/55688a5aab326aa7?tvc=2&q=chris+(+%22utf-8%22+OR+%22utf8%22+)+console#55688a5aab326aa7
> 
> I am posting an updated version that I hope applies to 2.6.15-rc6.
> Not sure what the correct X-Y-by: procedure is for this, as it originally
> is not my work (see URL).

Looks like I did the same backporting independently. Please look at 
http://www.linuxfromscratch.org/~alexander/patches/linux-2.6.14-utf8_input-1.patch 
(that does apply to the latest kernels if you use patch -Np1 -l -i 
linux-2.6.14-utf8_input-1.patch). Differences between our versions are 
described below.

> diff -Ppru linux-2.6.15-rc6-20051219230006/drivers/char/consolemap.c linux-2.6-AS22/drivers/char/consolemap.c
> --- linux-2.6.15-rc6-20051219230006/drivers/char/consolemap.c	2005-12-11 13:42:23.000000000 +0100
> +++ linux-2.6-AS22/drivers/char/consolemap.c	2005-12-19 21:53:25.000000000 +0100
> @@ -178,6 +178,7 @@ struct uni_pagedir {
>  	unsigned long	refcount;
>  	unsigned long	sum;
>  	unsigned char	*inverse_translations[4];
> +	u16		*inverse_trans_unicode;
>  	int		readonly;
>  };
>  
> @@ -208,6 +209,40 @@ static void set_inverse_transl(struct vc
>  	}
>  }
>  
> +static void set_inverse_trans_unicode(struct vc_data *conp, 
> +				      struct uni_pagedir *p)
> +{
> +	int i, j, k, glyph;
> +	u16 **p1, *p2;
> +	u16 *q;
> +	

I'd insert the "if (!p) return;" statement here, for consistency with 
non-Unicode path.

> +	q = p->inverse_trans_unicode;
> +	if (!q) {
> +		q = p->inverse_trans_unicode =
> +			kmalloc(MAX_GLYPH * sizeof(u16), GFP_KERNEL);
> +		if (!q)
> +			return;
> +	}
> +	memset(q, 0, MAX_GLYPH * sizeof(u16));
> +
> +	for (i = 0; i < 32; i++) {
> +		p1 = p->uni_pgdir[i];
> +		if (!p1)
> +			continue;
> +		for (j = 0; j < 32; j++) {
> +			p2 = p1[j];
> +			if (!p2)
> +				continue;
> +			for (k = 0; k < 64; k++) {
> +				glyph = p2[k];
> +				if (glyph >= 0 && glyph < MAX_GLYPH 
> +					       && q[glyph] < 32)
> +		  			q[glyph] = (i << 11) + (j << 6) + k;
> +			}
> +		}
> +	}
> +}
> +
>  unsigned short *set_translate(int m, struct vc_data *vc)
>  {
>  	inv_translate[vc->vc_num] = m;
> @@ -218,19 +253,29 @@ unsigned short *set_translate(int m, str
>   * Inverse translation is impossible for several reasons:
>   * 1. The font<->character maps are not 1-1.
>   * 2. The text may have been written while a different translation map
> - *    was active, or using Unicode.
> + *    was active.
>   * Still, it is now possible to a certain extent to cut and paste non-ASCII.
>   */
> -unsigned char inverse_translate(struct vc_data *conp, int glyph)
> +u16 inverse_translate(struct vc_data *conp, int glyph, int use_unicode)
>  {
>  	struct uni_pagedir *p;
> +	int m;
>  	if (glyph < 0 || glyph >= MAX_GLYPH)
>  		return 0;
> -	else if (!(p = (struct uni_pagedir *)*conp->vc_uni_pagedir_loc) ||
> -		 !p->inverse_translations[inv_translate[conp->vc_num]])
> +	else if (!(p = (struct uni_pagedir *)*conp->vc_uni_pagedir_loc))
>  		return glyph;
> -	else
> -		return p->inverse_translations[inv_translate[conp->vc_num]][glyph];
> +	else if (use_unicode) {
> +		if (!p->inverse_trans_unicode)
> +			return glyph;
> +		else
> +			return p->inverse_trans_unicode[glyph];
> +	} else {
> +		m = inv_translate[conp->vc_num];
> +		if (!p->inverse_translations[m])
> +			return glyph;
> +		else
> +			return p->inverse_translations[m][glyph];
> +	}
>  }
>  
>  static void update_user_maps(void)

There is probably a missed set_inverse_trans_unicode(vc_cons[i].d, p); 
in update_user_maps() just after set_inverse_transl(vc_cons[i].d, p, 
USER_MAP);

> @@ -354,6 +399,10 @@ static void con_release_unimap(struct un
>  		kfree(p->inverse_translations[i]);
>  		p->inverse_translations[i] = NULL;
>  	}
> +	if (p->inverse_trans_unicode) {
> +		kfree(p->inverse_trans_unicode);
> +		p->inverse_trans_unicode = NULL;
> +	}
>  }
>  
>  void con_free_unimap(struct vc_data *vc)
> @@ -512,6 +561,7 @@ int con_set_unimap(struct vc_data *vc, u
>  
>  	for (i = 0; i <= 3; i++)
>  		set_inverse_transl(vc, p, i); /* Update all inverse translations */
> +	set_inverse_trans_unicode(vc, p);
>    
>  	return err;
>  }
> @@ -562,6 +612,7 @@ int con_set_default_unimap(struct vc_dat
>  
>  	for (i = 0; i <= 3; i++)
>  		set_inverse_transl(vc, p, i);	/* Update all inverse translations */
> +	set_inverse_trans_unicode(vc, p);
>  	dflt = p;
>  	return err;
>  }
> @@ -618,6 +669,19 @@ void con_protect_unimap(struct vc_data *
>  		p->readonly = rdonly;
>  }
>  
> +/* may be called during an interrupt */
> +u32 conv_8bit_to_uni(unsigned char c)
> +{
> +	/* 
> +	 * Always use USER_MAP. This function is used by the keyboard,
> +	 * which shouldn't be affected by G0/G1 switching, etc.
> +	 * If the user map still contains default values, i.e. the 
> +	 * direct-to-font mapping, then assume user is using Latin1.
> +	 */
> +	unsigned short uni = translations[USER_MAP][c];
> +	return uni == (0xf000 | c) ? c : uni;
> +}
> +
>  int
>  conv_uni_to_pc(struct vc_data *conp, long ucs) 
>  {
> diff -Ppru linux-2.6.15-rc6-20051219230006/drivers/char/keyboard.c linux-2.6-AS22/drivers/char/keyboard.c
> --- linux-2.6.15-rc6-20051219230006/drivers/char/keyboard.c	2005-12-19 21:53:05.000000000 +0100
> +++ linux-2.6-AS22/drivers/char/keyboard.c	2005-12-19 21:53:25.000000000 +0100
> @@ -34,6 +34,7 @@
>  #include <linux/init.h>
>  #include <linux/slab.h>
>  
> +#include <linux/consolemap.h>
>  #include <linux/kbd_kern.h>
>  #include <linux/kbd_diacr.h>
>  #include <linux/vt_kern.h>
> @@ -353,6 +354,15 @@ static void to_utf8(struct vc_data *vc, 
My version of to_utf8() takes uint as a second argument and handles 
values beyonf 0xffff.

>  	}
>  }
>  
> +static void put_8bit(struct vc_data *vc, u8 c)
> +{
> +	if (kbd->kbdmode != VC_UNICODE || c < 32 || c == 127) 
> +		/* Don't translate control chars */
> +		put_queue(vc, c);
> +	else
> +		to_utf8(vc, conv_8bit_to_uni(c));
> +}
> +
>  /*
>   * Called after returning from RAW mode or when changing consoles - recompute
>   * shift_down[] and shift_state from key_down[] maybe called when keymap is
> @@ -413,7 +423,7 @@ static unsigned char handle_diacr(struct
>  	if (ch == ' ' || ch == d)
>  		return d;
>  
> -	put_queue(vc, d);
> +	put_8bit(vc, d);
>  	return ch;
>  }
>  
> @@ -423,7 +433,7 @@ static unsigned char handle_diacr(struct
>  static void fn_enter(struct vc_data *vc, struct pt_regs *regs)
>  {
>  	if (diacr) {
> -		put_queue(vc, diacr);
> +		put_8bit(vc, diacr);
>  		diacr = 0;
>  	}
>  	put_queue(vc, 13);
> @@ -632,7 +642,7 @@ static void k_self(struct vc_data *vc, u
>  		diacr = value;
>  		return;
>  	}
> -	put_queue(vc, value);
> +	put_8bit(vc, value);
>  }
>  
>  /*

In k_shift(), there is a difference in the second argument of to_utf8(). 
My version doesn't have "& 0xffff" because of the abovementioned changes 
to this function.

> diff -Ppru linux-2.6.15-rc6-20051219230006/drivers/char/selection.c linux-2.6-AS22/drivers/char/selection.c
> --- linux-2.6.15-rc6-20051219230006/drivers/char/selection.c	2005-12-11 13:42:24.000000000 +0100
> +++ linux-2.6-AS22/drivers/char/selection.c	2005-12-19 21:53:25.000000000 +0100
> @@ -20,6 +20,7 @@
>  
>  #include <asm/uaccess.h>
>  
> +#include <linux/kbd_kern.h>
>  #include <linux/vt_kern.h>
>  #include <linux/consolemap.h>
>  #include <linux/selection.h>
> @@ -34,6 +35,7 @@ extern void poke_blanked_console(void);
>  /* Variables for selection control. */
>  /* Use a dynamic buffer, instead of static (Dec 1994) */
>  struct vc_data *sel_cons;		/* must not be disallocated */
> +static int use_unicode;
>  static volatile int sel_start = -1; 	/* cleared by clear_selection */
>  static int sel_end;
>  static int sel_buffer_lth;
> @@ -54,10 +56,8 @@ static inline void highlight_pointer(con
>  	complement_pos(sel_cons, where);
>  }
>  
> -static unsigned char
> -sel_pos(int n)
> -{
> -	return inverse_translate(sel_cons, screen_glyph(sel_cons, n));
> +static u16 sel_pos(int n) {
> +    return inverse_translate(sel_cons, screen_glyph(sel_cons, n), use_unicode);
>  }
>  
>  /* remove the current selection highlight, if any,
> @@ -86,8 +86,8 @@ static u32 inwordLut[8]={
>    0xFF7FFFFF  /* latin-1 accented letters, not division sign */
>  };
>  
> -static inline int inword(const unsigned char c) {
> -	return ( inwordLut[c>>5] >> (c & 0x1F) ) & 1;
> +static inline int inword(const u16 c) {
> +    return c > 0xff || ((inwordLut[c >> 5] >> (c & 0x1F)) & 1);
>  }
>  
>  /* set inwordLut contents. Invoked by ioctl(). */
> @@ -108,13 +108,35 @@ static inline unsigned short limit(const
>  	return (v > u) ? u : v;
>  }
>  
> +/* stores the char in UTF8 and returns the number of bytes used (1-3) */
> +int store_utf8(u16 c, char *p)  {
> +	if (c < 0x80) {
> +		/* 0******* */
> +		p[0] = c;
> +		return 1;
> +	} else if (c < 0x800) {
> +		/* 110***** 10****** */
> +		p[0] = 0xc0 | (c >> 6);
> +		p[1] = 0x80 | (c & 0x3f);
> +		return 2;
> + 	} else {
> +		/* 1110**** 10****** 10****** */
> +		p[0] = 0xe0 | (c >> 12);
> +		p[1] = 0x80 | ((c >> 6) & 0x3f);
> +		p[2] = 0x80 | (c & 0x3f);
> +		return 3;
> + 	}
> +}
> +
>  /* set the current selection. Invoked by ioctl() or by kernel code. */
>  int set_selection(const struct tiocl_selection __user *sel, struct tty_struct *tty)
>  {
>  	struct vc_data *vc = vc_cons[fg_console].d;
>  	int sel_mode, new_sel_start, new_sel_end, spc;
>  	char *bp, *obp;
> -	int i, ps, pe;
> +        int i, ps, pe, multiplier;
> +        u16 c;
> +        struct kbd_struct *kbd = kbd_table + fg_console;
>  
>  	poke_blanked_console();
>  
> @@ -158,6 +180,7 @@ int set_selection(const struct tiocl_sel
>  		clear_selection();
>  		sel_cons = vc_cons[fg_console].d;
>  	}
> +	use_unicode = kbd && kbd->kbdmode == VC_UNICODE;
>  
>  	switch (sel_mode)
>  	{
> @@ -240,7 +263,8 @@ int set_selection(const struct tiocl_sel
>  	sel_end = new_sel_end;
>  
>  	/* Allocate a new buffer before freeing the old one ... */
> -	bp = kmalloc((sel_end-sel_start)/2+1, GFP_KERNEL);
> +	multiplier = use_unicode ? 3 : 1;  /* chars can take up to 3 bytes */
> +	bp = kmalloc((sel_end-sel_start)/2*multiplier+1, GFP_KERNEL);
>  	if (!bp) {
>  		printk(KERN_WARNING "selection: kmalloc() failed\n");
>  		clear_selection();
> @@ -251,8 +275,12 @@ int set_selection(const struct tiocl_sel
>  
>  	obp = bp;
>  	for (i = sel_start; i <= sel_end; i += 2) {
> -		*bp = sel_pos(i);
> -		if (!isspace(*bp++))
> +		c = sel_pos(i);
> +		if (use_unicode)
> +			bp += store_utf8(c, bp);
> +		else
> +			*bp++ = c;
> +		if (!isspace(c))
>  			obp = bp;
>  		if (! ((i + 2) % vc->vc_size_row)) {
>  			/* strip trailing blanks from line and add newline,
> diff -Ppru linux-2.6.15-rc6-20051219230006/include/linux/consolemap.h linux-2.6-AS22/include/linux/consolemap.h
> --- linux-2.6.15-rc6-20051219230006/include/linux/consolemap.h	2005-10-28 02:02:08.000000000 +0200
> +++ linux-2.6-AS22/include/linux/consolemap.h	2005-12-19 21:53:25.000000000 +0100
> @@ -10,6 +10,7 @@
>  
>  struct vc_data;
>  
> -extern unsigned char inverse_translate(struct vc_data *conp, int glyph);
> +extern u16 inverse_translate(struct vc_data *conp, int glyph, int use_unicode);
>  extern unsigned short *set_translate(int m, struct vc_data *vc);
>  extern int conv_uni_to_pc(struct vc_data *conp, long ucs);
> +extern u32 conv_8bit_to_uni(unsigned char c);
> #eof
> 
> 
> 
> Jan Engelhardt