Re: [PATCH RFC 3/6] lib/charset: Map cp437 low chars (0x01 - 0x1f) from unicode

On 1/17/24 23:24, Janne Grunau via B4 Relay wrote:

From: Janne Grunau j@jannau.net

Add mappings for code points 1 - 31 as those code points in code page 437 are graphics. Thios fixes rendering issues of various EFI boot loaders (grub2,

%s/Thios/This/

sd-boot, ...) using EFI_SIMPLE_TEXT_OUTPUT_PROTOCOL.

Could you, please, explain the reason for the change a bit more in depth.

The applications above produce UTF-16. A Truetype font should not have symbols for positions 0x00-0x1f. Codepage 437 is only relevant for FAT file names that might use this character set.

Why do you want to translate well define Unicode code points to characters 0x00-0x1f?

Best regards

Heinrich

Signed-off-by: Janne Grunau j@jannau.net

include/charset.h | 2 +- include/cp1250.h | 12 ++++++++++-- include/cp437.h | 12 ++++++++++-- lib/charset.c | 9 ++++++--- lib/efi_loader/efi_unicode_collation.c | 2 +- 5 files changed, 28 insertions(+), 9 deletions(-)

diff --git a/include/charset.h b/include/charset.h index 714382e1c1..c51c29235f 100644 --- a/include/charset.h +++ b/include/charset.h @@ -16,7 +16,7 @@ /*

• codepage_437 - Unicode to codepage 437 translation table

*/ -extern const u16 codepage_437[128]; +extern const u16 codepage_437[160];

/**

• console_read_unicode() - read Unicode code point from console

diff --git a/include/cp1250.h b/include/cp1250.h index adacf8a958..b762c78d9f 100644 --- a/include/cp1250.h +++ b/include/cp1250.h @@ -1,10 +1,18 @@ /* SPDX-License-Identifier: GPL-2.0+ */

/*

• • Constant CP1250 contains the Unicode code points for characters 0x80 - 0xff
• • of the code page 1250.

• • Constant CP1250 contains the Unicode code points for characters 0x00 - 0x1f
• • and 0x80 - 0xff of the code page 1250.
  */ #define CP1250 { \
• 0x0000, 0x0000, 0x0000, 0x0000, \
• 0x0000, 0x0000, 0x0000, 0x0000, \
• 0x0000, 0x0000, 0x0000, 0x0000, \
• 0x0000, 0x0000, 0x0000, 0x0000, \
• 0x0000, 0x0000, 0x0000, 0x0000, \
• 0x0000, 0x0000, 0x0000, 0x0000, \
• 0x0000, 0x0000, 0x0000, 0x0000, \
• 0x0000, 0x0000, 0x0000, 0x0000, \ 0x20ac, 0x0000, 0x201a, 0x0000, \ 0x201e, 0x2026, 0x2020, 0x2021, \ 0x0000, 0x2030, 0x0160, 0x2039, \

diff --git a/include/cp437.h b/include/cp437.h index 0b2b97132e..5093130f5e 100644 --- a/include/cp437.h +++ b/include/cp437.h @@ -1,10 +1,18 @@ /* SPDX-License-Identifier: GPL-2.0+ */

/*

• • Constant CP437 contains the Unicode code points for characters 0x80 - 0xff
• • of the code page 437.

• • Constant CP437 contains the Unicode code points for characters 0x00 - 0x1f
• • and 0x80 - 0xff of the code page 437.
  */ #define CP437 { \
• 0x0000, 0x263a, 0x263b, 0x2665, \
• 0x2666, 0x2663, 0x2660, 0x2022, \
• 0x25d8, 0x25cb, 0x25d9, 0x2642, \
• 0x2640, 0x266a, 0x266b, 0x263c, \
• 0x25ba, 0x25c4, 0x2195, 0x203c, \
• 0x00b6, 0x00a7, 0x25ac, 0x21a8, \
• 0x2191, 0x2193, 0x2192, 0x2190, \
• 0x221f, 0x2194, 0x25b2, 0x25bc, \ 0x00c7, 0x00fc, 0x00e9, 0x00e2, \ 0x00e4, 0x00e0, 0x00e5, 0x00e7, \ 0x00ea, 0x00eb, 0x00e8, 0x00ef, \

diff --git a/lib/charset.c b/lib/charset.c index 5e4c4f948a..1f8480150a 100644 --- a/lib/charset.c +++ b/lib/charset.c @@ -16,7 +16,7 @@ /**

• codepage_437 - Unicode to codepage 437 translation table

*/ -const u16 codepage_437[128] = CP437; +const u16 codepage_437[160] = CP437;

static struct capitalization_table capitalization_table[] = #ifdef CONFIG_EFI_UNICODE_CAPITALIZATION @@ -517,9 +517,12 @@ int utf_to_cp(s32 *c, const u16 *codepage) int j;

/* Look up codepage translation */

• for (j = 0; j < 0x80; ++j) {
  

• for (j = 0; j < 0xA0; ++j) {
  if (*c == codepage[j]) {
  

• 		*c = j + 0x80;
  

• 		if (j < 0x20)
  

• 			*c = j;
  

• 		else
  

• 			*c = j + 0x60;
  	return 0;
  }
  

  }

diff --git a/lib/efi_loader/efi_unicode_collation.c b/lib/efi_loader/efi_unicode_collation.c index c4c7572063..4b2c52918a 100644 --- a/lib/efi_loader/efi_unicode_collation.c +++ b/lib/efi_loader/efi_unicode_collation.c @@ -257,7 +257,7 @@ static void EFIAPI efi_fat_to_str(struct efi_unicode_collation_protocol *this, for (i = 0; i < fat_size; ++i) { c = (unsigned char)fat[i]; if (c > 0x80)

• 	c = codepage[c - 0x80];
  

• 	c = codepage[c - 0x60];
  

  string[i] = c; if (!c) break;