Backport of 4dcf0b41c6b01f45e141https://github.com/taglib/taglib/pull/77
Tested with files larger than 2GB which have been created using
sox -n -r 44100 -C 320 large.mp3 synth 58916 sine 440 channels 2
sox -n -r 44100 -C 0 large.flac synth 25459 sine 440 channels 2
sox -n -r 44100 -C 10 large.ogg synth 229806 sine 440 channels 2
sox -n -r 44100 large.wav synth 6692 sine 440 channels 2
ffmpeg -f lavfi -i "sine=frequency=440:duration=244676" -y large.m4a
The only file which was readable with the tagreader example
before this commit was large.ogg. The problem is that long on
Windows is only 32-bit (also in LLP64 data model of 64-bit
compilation target) and all the file offsets using long are
too small for large files. Now long is replaced by offset_t
(defined to be long long on Windows and off_t on UNIX) for such
cases and some unsigned long are now size_t, which has the
correct size even on Windows.