#458 libFLAC: crash when giving underestimated total samples

[tmkk]

When FLAC__stream_encoder_set_verify is set to true and giving underestimated total sample count in FLAC__stream_encoder_set_total_samples_estimate, an encoder crashes at the end of a process (possibly in FLAC__stream_encoder_finish). The crash doesn't happen when verify is turned off.

See the code attached to reproduce the crash.

[tmkk]

My investigation

Direct reason: buffer overflows in append_to_verify_fifo_[interleaved_]
Fundamental reason: decoder for verify may stop processing (and stop consuming FIFO) when total samples in STREAMINFO is a non-zero value, while encoder still continues to fill FIFO
Solution: force set total samples to zero when first write STREAMINFO in FLAC__StreamEncoderInitStatus in case verify is enabled

This patch solves the problem.