[source_sndfile] avoid declaration after statement
[source_sndfile] set error message when reading after close
[source_sndfile] fix reading sizes when resampling
[source_sndfile] use padding helpers
[source_sndfile] validate input sizes to prevent invalid reads, remove channel copying for now
[source] simplify and avoid unrequired checks
[io] remove useless check in source_sndfile
src/io/source_sndfile.c: allow closing twice
src/io/source_sndfile.c: make sure seek position is >= 0
src/io/source_sndfile.c: call sf_seek after checking for s->handle
src/io/source_sndfile.c: avoid seeking in closed file
src/aubio_priv.h: move include config.h here
src/io/source_sndfile.c
src/io/source_sndfile.c: add missing floor in ratio comparison
src/io/source_sndfile.c: set handle to null after sucessful close
src/io/source_sndfile.c: add support for multi-channel resampling
src/io/source_sndfile.c: improve formatting
src/io/source_sndfile.c: approximate duration when resampling
src/io/source_sndfile.h: add _get_duration
src/io/: also copy null ending char