This is used for figuring out the close transaction balances,
but can also be used in the future for dynamic fee support.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Use our own structure with the information we need about HTLCs,
and remove protobufs from the API.
The is_funder() helper goes inside gather_updates.h.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
This gets truncated for on-chain transactions (thus, rounding may
contribute to fees).
This also means we currently have an upper bound of 0.04 BTC per HTLC;
this can be increased later if required.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
This shows where funds are going at any time (fees vs to each side).
funding.c is mainly rewritten, and should be clearer now.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Both sides elect a commitment fee, and the lowest is chosen. That means
you can't game the other side (but if you offer too low, then can error
out of course).
Fees are split 50-50 if possible: originally the whole fee has to be
paid by the (single) funder. Neither side can withdraw funds which
would make them unable to pay fees.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Most complex change was gather_updates(), which handles all the "what
is the current state of the channel" logic for our dumb test utils.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Rusty Russell