Mercurial > sdl-ios-xcode
annotate src/video/Xext/README @ 3539:f2846bf19360
Fixed bug #896
John Popplewell 2009-12-08 23:05:50 PST
Originally reported by AKFoerster on the mailing list.
Error decoding UTF8 Russian text to UTF-16LE on Windows, but specifically on
platforms without iconv support (the default on Windows).
Valid UTF8 characters are flagged as being overlong and then substituted by the
UNKNOWN_UNICODE character.
After studying the testiconv.c example program, reading the RFCs and putting
some printf statements in SDL_iconv.c the problem is in a test for 'Maximum
overlong sequences', specifically 4.2.1, which is carried out by the following
code:
} else if ( p[0] >= 0xC0 ) {
if ( (p[0] & 0xE0) != 0xC0 ) {
/* Skip illegal sequences
return SDL_ICONV_EILSEQ;
*/
ch = UNKNOWN_UNICODE;
} else {
if ( (p[0] & 0xCE) == 0xC0 ) { <<<<<<<< here
overlong = SDL_TRUE;
}
ch = (Uint32)(p[0] & 0x1F);
left = 1;
}
} else {
Here is the 2-byte encoding of a character in range 00000080 - 000007FF
110xxxxx 10xxxxxx
The line in question is supposed to be checking for an overlong sequence which
would be less than
11000001 10111111
which should be represented as a single byte.
BUT, the mask value (0xCE) is wrong, it isn't checking the top-most bit:
11000001 value
11001110 mask (incorrect)
^
and should be (0xDE):
11000001 value
11011110 mask (correct)
making the above code:
} else if ( p[0] >= 0xC0 ) {
if ( (p[0] & 0xE0) != 0xC0 ) {
/* Skip illegal sequences
return SDL_ICONV_EILSEQ;
*/
ch = UNKNOWN_UNICODE;
} else {
if ( (p[0] & 0xDE) == 0xC0 ) { <<<<<<<< here
overlong = SDL_TRUE;
}
ch = (Uint32)(p[0] & 0x1F);
left = 1;
}
} else {
I can supply a test program and/or a patch if required,
best regards,
John Popplewell
author | Sam Lantinga <slouken@libsdl.org> |
---|---|
date | Fri, 11 Dec 2009 08:03:43 +0000 |
parents | b87d8d4c205d |
children |
rev | line source |
---|---|
292
eadc0746dfaf
Added SDL_LockRect() and SDL_UnlockRect()
Sam Lantinga <slouken@libsdl.org>
parents:
diff
changeset
|
1 |
eadc0746dfaf
Added SDL_LockRect() and SDL_UnlockRect()
Sam Lantinga <slouken@libsdl.org>
parents:
diff
changeset
|
2 The reason these libraries are built outside of the standard XFree86 |
eadc0746dfaf
Added SDL_LockRect() and SDL_UnlockRect()
Sam Lantinga <slouken@libsdl.org>
parents:
diff
changeset
|
3 tree is so that they can be linked as shared object code directly into |
eadc0746dfaf
Added SDL_LockRect() and SDL_UnlockRect()
Sam Lantinga <slouken@libsdl.org>
parents:
diff
changeset
|
4 SDL without causing any symbol collisions with code in the application. |
eadc0746dfaf
Added SDL_LockRect() and SDL_UnlockRect()
Sam Lantinga <slouken@libsdl.org>
parents:
diff
changeset
|
5 |
eadc0746dfaf
Added SDL_LockRect() and SDL_UnlockRect()
Sam Lantinga <slouken@libsdl.org>
parents:
diff
changeset
|
6 You can't link static library code into shared libraries on non-x86 |
eadc0746dfaf
Added SDL_LockRect() and SDL_UnlockRect()
Sam Lantinga <slouken@libsdl.org>
parents:
diff
changeset
|
7 Linux platforms. Since these libraries haven't become standard yet, |
eadc0746dfaf
Added SDL_LockRect() and SDL_UnlockRect()
Sam Lantinga <slouken@libsdl.org>
parents:
diff
changeset
|
8 we'll just include them directly. |
eadc0746dfaf
Added SDL_LockRect() and SDL_UnlockRect()
Sam Lantinga <slouken@libsdl.org>
parents:
diff
changeset
|
9 |
690
b87d8d4c205d
Fixed use of SDL with XInitThreads()
Sam Lantinga <slouken@libsdl.org>
parents:
292
diff
changeset
|
10 These sources are synchronized with XFree86 4.2.1 |