* refactor: directly copy from socket to incoming payload
* refactor: directly process the incoming field
There is no need to copy the payload to a new buffer before processing.
`process_peer_message()` isn't going to return until it's done, and nothing else is going to mess with the incoming field while inside `process_peer_message()`.
* refactor: remove while loop
* add assert
* fix: correct condition to advertise pex support in ltep handshake
1. Advertise pex support regardless of whether the peer had advertised pex support. No reason to give up an opportunity to advertise pex support just because our direct peer does not support it.
2. Check if pex is enabled in global settings as well.
* perf: use libtransmission::StackBuffer in variant-benc
* perf: use libtransmission::StackBuffer in variant-json
* perf: use libtransmission::StackBuffer in handshake
* perf: use libtransmission::StackBuffer in peer-msgs
* perf: use libtransmission::StackBuffer in peer-io
* Revert "perf: use libsmall in libtransmission, pt 3 (#5653)"
This reverts commit 3b03494580.
* Revert "perf: use small in libtransmission (#5650)"
This reverts commit 559f6f0332.
* refactor: reimplement Buffer using small
* refactor: use SmallBuffer in announcer-udp
* refactor: use SmallBuffer in variant-json
* refactor: use SmallBuffer in variant-benc
* refactor: use SmallBuffer in handshake
* refactor: use SmallBuffer in peer-msgs
* refactor: delete move semantics on stack-based buffers
Write non-piece peer messages directly to the peer's outbuf instead of
waiting for a pulse() message to refill it. This can help with latency
sending messages out.
Change the semantics of `tr_peerIo::get_write_buffer_space()`: this is
now interpreted as the preferred minimum size, rather than the maximum.
It's OK to enqueue an outgoing piece message as long as there's _some_
space left, even if the message is larger than that space.
Build peer messages with template fold expressions. This lets us move
all the message-building to a single function and add some sanity checks
to the outgoing messages.
