On 26.08.18 20:34, Heinrich Schuchardt wrote:
On 08/26/2018 08:05 PM, Alexander Graf wrote:
On 11.08.18 17:28, Heinrich Schuchardt wrote:
The width and precision of the printf() function refer to the number of characters not to the number of bytes printed.
Signed-off-by: Heinrich Schuchardt xypron.glpk@gmx.de
lib/vsprintf.c | 22 +++++++++++++--------- 1 file changed, 13 insertions(+), 9 deletions(-)
diff --git a/lib/vsprintf.c b/lib/vsprintf.c index a07128ad96..b7eb9d5f5e 100644 --- a/lib/vsprintf.c +++ b/lib/vsprintf.c @@ -280,18 +280,22 @@ static char *string16(char *buf, char *end, u16 *s, int field_width, int precision, int flags) { u16 *str = s ? s : L"<NULL>";
- int utf16_len = u16_strnlen(str, precision);
- u8 utf8[utf16_len * MAX_UTF8_PER_UTF16];
- int utf8_len, i;
- utf8_len = utf16_to_utf8(utf8, str, utf16_len) - utf8;
ssize_t i, len = utf16_strnlen(str, precision);
if (!(flags & LEFT))
while (utf8_len < field_width--)
for (; len < field_width; --field_width) ADDCH(buf, ' ');
- for (i = 0; i < utf8_len; ++i)
ADDCH(buf, utf8[i]);- while (utf8_len < field_width--)
- for (i = 0; i < len; ++i) {
s32 code = utf16_get((const u16 **)&str);if (code < 0) {code = '?';if (*str)++str;}utf8_put(code, &buf);Can you introduce or reuse a strcpy() helper in charset.c for this? That way the compiler has the chance to inline utf16_get() and utf8_put() and make the function fast.
strcpy() works on bytes not on multi-byte utf-8 characters. So it is unclear to me how I should make use of strcpy() here.
What I was trying to imply is that what you're doing here is very similar to utf8_utf16_strncpy(). Maybe we can reuse the same function or at least something very similar.
Of cause we could define utf8_put() and utf8_get() as inline function. But that would increase code size. Is this what you would prefer? I would guess that the serial interface is always the slowest part of text output anyway.
Real serial output is definitely orders of magnitude slower, I agree. But if we can make the code easier to read along the way I'm all for it ;).
I think what it boils down to is that I'd prefer if we keep utf{8,16}_{get,put}() as local to charset.c as we can and instead put slightly higher level wrappers around them, like you did for pretty much everything else.
Alex