lavfi/pthread: Avoid crashes/odd behavior caused by spurious wakeups

This is similar to 5152196b2b47d446d9a509b9bfb318daa26a1f2b.

Signed-off-by: Derek Buitenhuis <derek.buitenhuis@gmail.com>
nut: Fix unchecked allocations

Signed-off-by: Derek Buitenhuis <derek.buitenhuis@gmail.com>
avcodec/vcr1: Fix bitstream input size check

Found-by: Mateusz "j00ru" Jurczyk and Gynvael Coldwind
Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
avcodec/vcr1: print the actual size when its insufficient

Signed-off-by: Michael Niedermayer <michaelni@gmx.at>