SM6FBQ / HackRF clone - History

Merge pull request #1168 from martinling/flush-callback

Provide a callback for TX flush, rather than a wait function.

If TX callback sets valid_length to 0, treat as end of data.

Don't repeat file that can't advance its position.

This avoids a confusing condition when hackrf_transfer is reading from
stdin with -R in which it does not repeat previous data but repeatedly
restarts reading new data after the user types Ctrl-D to indicate EOF.

The -R option should repeat previous data or should do nothing if the
input file cannot be rewound.

Revert rename of byte_count now that we only have one count.

Fold transfer_finished function into libusb transfer callback.

Expand lock scope in libusb transfer callback.

This is required since cancel_transfers will also cancel the flush.