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WavLoader: Search for DATA marker by reading single bytes

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Previously 4 bytes at once were read and compared to the string
"DATA". This worked when the DATA marker was aligned on a 32-bit
boundary relative to the start of the file. However, this is not
guranteed to always be the case, and for some files the loader
would just keep searching for the marker.
This commit is contained in:
Till Mayer 2020-06-18 20:00:32 +02:00 • committed by Andreas Kling
parent c053537321
commit 072e6a6405
1 changed files with 19 additions and 8 deletions
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27
Libraries/LibAudio/WavLoader.cpp
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@ -155,16 +155,27 @@ bool WavLoader::parse_header()
// Read chunks until we find DATA
bool found_data = false;
u32 data_sz = 0;
u8 search_byte = 0;
while (true) {
u32 chunk_id;
stream >> chunk_id;
CHECK_OK("Reading chunk ID searching for data");
stream >> search_byte;
CHECK_OK("Reading byte searching for data");
if (search_byte != 0x64) //D
continue;
stream >> search_byte;
CHECK_OK("Reading next byte searching for data");
if (search_byte != 0x61) //A
continue;
u16 search_remaining = 0;
stream >> search_remaining;
CHECK_OK("Reading remaining bytes searching for data");
if (search_remaining != 0x6174) //TA
continue;
stream >> data_sz;
CHECK_OK("Reading chunk size searching for data");
if (chunk_id == 0x61746164) { // DATA
found_data = true;
break;
}
found_data = true;
break;
}
ok = ok && found_data;