Mercurial > sdl-ios-xcode
view src/audio/SDL_wave.h @ 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 | 99210400e8b9 |
| children | f7b03b6838cb |
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/* SDL - Simple DirectMedia Layer Copyright (C) 1997-2009 Sam Lantinga This library is SDL_free software; you can redistribute it and/or modify it under the terms of the GNU Lesser General Public License as published by the Free Software Foundation; either version 2.1 of the License, or (at your option) any later version. This library is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for more details. You should have received a copy of the GNU Lesser General Public License along with this library; if not, write to the Free Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA Sam Lantinga slouken@libsdl.org */ #include "SDL_config.h" /* WAVE files are little-endian */ /*******************************************/ /* Define values for Microsoft WAVE format */ /*******************************************/ #define RIFF 0x46464952 /* "RIFF" */ #define WAVE 0x45564157 /* "WAVE" */ #define FACT 0x74636166 /* "fact" */ #define LIST 0x5453494c /* "LIST" */ #define FMT 0x20746D66 /* "fmt " */ #define DATA 0x61746164 /* "data" */ #define PCM_CODE 0x0001 #define MS_ADPCM_CODE 0x0002 #define IEEE_FLOAT_CODE 0x0003 #define IMA_ADPCM_CODE 0x0011 #define MP3_CODE 0x0055 #define WAVE_MONO 1 #define WAVE_STEREO 2 /* Normally, these three chunks come consecutively in a WAVE file */ typedef struct WaveFMT { /* Not saved in the chunk we read: Uint32 FMTchunk; Uint32 fmtlen; */ Uint16 encoding; Uint16 channels; /* 1 = mono, 2 = stereo */ Uint32 frequency; /* One of 11025, 22050, or 44100 Hz */ Uint32 byterate; /* Average bytes per second */ Uint16 blockalign; /* Bytes per sample block */ Uint16 bitspersample; /* One of 8, 12, 16, or 4 for ADPCM */ } WaveFMT; /* The general chunk found in the WAVE file */ typedef struct Chunk { Uint32 magic; Uint32 length; Uint8 *data; } Chunk; /* vi: set ts=4 sw=4 expandtab: */