It's a u64, we should pass by copy. This is a big sweeping change,
but mainly mechanical (change one, compile, fix breakage, repeat).
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
This has the benefit of being shorter, as well as more reliable (you
will get a link error if we can't print it, not a runtime one!).
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Min. Cost Flow does not take into account fees when computing a flow
with liquidity constraints.
This is a work-around solution that reduces the amount on every route to
respect the liquidity bound. The deficity in the delivered amount is
solved by running MCF once again.
Changes:
1. the function `flow_complete` allocates amounts to send over the set of routes
computed by the MCF algorithm, but it does not allocate more than liquidity
bound of the route. For this reason `minflow` returns a set of routes that
satisfy the liquidity bounds but it is not guaranteed that the total payment
reaches the destination therefore there could a deficit in the delivery:
`deficit = amount_to_deliver - delivering`.
2. in the function `add_payflows` after `minflow` returns a set of routes we
call `flows_fit_amount` that tries to a allocate the `deficit` in the routes
that the MCF have computed.
3. if the resulting flows pass all payment constraints then we update
`amount_to_deliver = amount_to_deliver - delivering`, and the loop
repeats as long as `amount_to_deliver` is not zero.
In other words, the excess amount, beyond the liquidity bound,
in the routes is removed and then we try to allocate it
into known routes, otherwise we do a whole MCF again just for the
remaining amount.
Fixes issue #6599
The tests will wait until it's locally enabled, but it might not have
the update in the gossip store. So have renepay enhance its local
view even if it already knows about the channel (this is correct
anyway, it just isn't very important usually).
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
```
Flow 391: amount=23528000msat prob=0.000 fees=1023msat delay=140 path=-2471854x37x4/1(min=max=23528783msat)->-2414928x98x0/0->
Flow 391: Failure of 23529023msat for 2471854x37x4/1 capacity [23528783msat,23528783msat] -> [23528783msat,23528783msat]
```
We added fees and went over capacity! This screams of a deeper logic
bug, but renepay is experimental and it's release day so hack around
it for now...
Reported-by: https://github.com/daywalker90
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
It now looks like (for test_hardmpp):
```
# we have computed a set of 1 flows with probability 0.328, fees 0msat and delay 23
# Flow 1: amount=1800000000msat prob=0.328 fees=0msat delay=12 path=-103x2x0/1(min=max=4294967295msat)->-103x5x0/0->-103x3x0/1->
# Flow 1: Failed at node #1 (WIRE_TEMPORARY_CHANNEL_FAILURE): failed: WIRE_TEMPORARY_CHANNEL_FAILURE (reply from remote)
# Flow 1: Failure of 1800000000msat for 103x5x0/0 capacity [0msat,3000000000msat] -> [0msat,1799999999msat]
# we have computed a set of 2 flows with probability 0.115, fees 0msat and delay 23
# Flow 2: amount=500000000msat prob=0.475 fees=0msat delay=12 path=-103x6x0/0(min=max=4294967295msat)->-103x1x0/1->-103x4x0/1->
# Flow 3: amount=1300000000msat prob=0.242 fees=0msat delay=12 path=-103x2x0/1(min=max=4294967295msat)->-103x5x0/0(max=1799999999msat)->-103x3x0/1->
# Flow 3: Failed at node #1 (WIRE_TEMPORARY_CHANNEL_FAILURE): failed: WIRE_TEMPORARY_CHANNEL_FAILURE (reply from remote)
# Flow 3: Failure of 1300000000msat for 103x5x0/0 capacity [0msat,1799999999msat] -> [0msat,1299999999msat]
# we have computed a set of 2 flows with probability 0.084, fees 0msat and delay 23
# Flow 4: amount=260000000msat prob=0.467 fees=0msat delay=12 path=-103x6x0/0(500000000msat in 1 htlcs,min=max=4294967295msat)->-103x1x0/1(500000000msat in 1 htlcs)->-103x4x0/1(500000000msat in 1 htlcs)->
# Flow 5: amount=1040000000msat prob=0.179 fees=0msat delay=12 path=-103x2x0/1(min=max=4294967295msat)->-103x5x0/0(max=1299999999msat)->-103x3x0/1->
# Flow 5: Failed at node #1 (WIRE_TEMPORARY_CHANNEL_FAILURE): failed: WIRE_TEMPORARY_CHANNEL_FAILURE (reply from remote)
# Flow 5: Failure of 1040000000msat for 103x5x0/0 capacity [0msat,1299999999msat] -> [0msat,1039999999msat]
# we have computed a set of 2 flows with probability 0.052, fees 0msat and delay 23
# Flow 6: amount=120000000msat prob=0.494 fees=0msat delay=12 path=-103x6x0/0(760000000msat in 2 htlcs,min=max=4294967295msat)->-103x1x0/1(760000000msat in 2 htlcs)->-103x4x0/1(760000000msat in 2 htlcs)->
# Flow 7: amount=920000000msat prob=0.105 fees=0msat delay=12 path=-103x2x0/1(min=max=4294967295msat)->-103x5x0/0(max=1039999999msat)->-103x3x0/1->
# Flow 7: Success
```
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
There are a few fields in `struct renepay` which are genuinely
transient, but it makes the code much harder to follow than simply
having a single structure.
More cleanups will follow, but this is the minimal set.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
- adopt "const <type> *"convention
- remove use_shadow option for some pyln tests
- show prob. information of flows into paynotes
- show prob. of success of entire payment flow in paynotes
- minflow: We were not releasing the memory of flow arrays when replacing
them with a new canditate.
- use memleak_scan_obj in memleak_check
- replace u64 with size_t
Signed-off-by: Lagrang3 <eduardo.quintana@pm.me>
