Replace hand-rolled code with std::from_chars for better
maintainability.
The C++ std::from_chars function is intended to be as fast as possible,
so it is unlikely to be slower than the code it replaces. This change is
a net gain because it reduces the amount of hand-rolled code.
Apply a minor cleanup in `TypedField`:
* Remove a non-working and unused move constructor.
* Constrain the remaining constructor to not be overly generic enough as
to be used as a copy or move constructor.
Enhance the /crawl endpoint by publishing WebSocket/RPC ports in the
server_info response. The function processing requests to the /crawl
endpoint actually calls server_info internally, so this change enables a
server to advertise its WebSocket/RPC port(s) to peers via the /crawl
endpoint. `grpc` and `peer` ports are included as well.
The new `ports` array contains objects, each containing a `port` for the
listening port (number string), and an array `protocol` listing the
supported protocol(s).
This allows crawlers to build a richer topology without needing to
port-scan nodes. For non-admin users (including peers), the info about
*admin* ports is excluded.
Also increase test coverage for RPC ServerInfo.
Fix#2837.
Curtail the occurrence of order books that are blocked by reduced offers
with the implementation of the fixReducedOffersV1 amendment.
This commit identifies three ways in which offers can be reduced:
1. A new offer can be partially crossed by existing offers, so the new
offer is reduced when placed in the ledger.
2. An in-ledger offer can be partially crossed by a new offer in a
transaction. So the in-ledger offer is reduced by the new offer.
3. An in-ledger offer may be under-funded. In this case the in-ledger
offer is scaled down to match the available funds.
Reduced offers can block order books if the effective quality of the
reduced offer is worse than the quality of the original offer (from the
perspective of the taker). It turns out that, for small values, the
quality of the reduced offer can be significantly affected by the
rounding mode used during scaling computations.
This commit adjusts some rounding modes so that the quality of a reduced
offer is always at least as good (from the taker's perspective) as the
original offer.
The amendment is titled fixReducedOffersV1 because additional ways of
producing reduced offers may come to light. Therefore, there may be a
future need for a V2 amendment.
* Enable api_version 2, which is currently in beta. It is expected to be
marked stable by the next stable release.
* This does not change any defaults.
* The only existing tests changed were one that set the same flag, which
was now redundant, and a couple that tested versioning explicitly.
