Files
punktfunk/crates/punktfunk-core/Cargo.toml
T
enricobuehler 0f333460ec fix(core): grow UDP socket buffers — fixes 4K/5K video freezing on one frame
The data-plane UDP sockets used the OS default buffer (~208 KB on Linux, similar
on macOS), which is smaller than a single high-resolution frame burst: a
5120×1440 keyframe is ~130 packets the encode|send thread hands to sendmmsg at
once. The burst overflows the buffer — EAGAIN on the host send (now dropped, was
fatal) or a silent drop on the client recv — and because the data plane runs
infinite-GOP, one lost frame breaks every subsequent reference and the decode
freezes on the last good frame until an RFI refresh that may never catch up.
Symptom: connect at 5120×1440, see ONE frame, then a frozen image (audio + input
keep working — those ride QUIC, not this socket).

Set SO_SNDBUF/SO_RCVBUF to 8 MB (clamped by the OS to net.core.{w,r}mem_max on
Linux / kern.ipc.maxsockbuf on macOS); warn if the grant lands far below target so
an undersized host is diagnosable. The client side matters most — the SAME
UdpTransport backs the Apple client's data plane via the C ABI, and macOS grants
multi-MB buffers without any sysctl, so a rebuilt client stops losing frames.

Validated live, bazzite→client at 5120×1440: was 1319/1500 frames (12% loss →
freeze), now 1500/1500 @60 and 5279/5279 @240 (split-encode active), zero
mismatches, p50 1.9–3.4 ms. Host send buffer was still capped at 416 KB and lost
nothing — the loss was purely the client recv buffer.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
2026-06-11 13:28:02 +00:00

54 lines
2.4 KiB
TOML

[package]
name = "punktfunk-core"
description = "punktfunk shared protocol/transport/FEC core, exposed over a stable C ABI"
version.workspace = true
edition.workspace = true
rust-version.workspace = true
license.workspace = true
authors.workspace = true
repository.workspace = true
[lib]
name = "punktfunk_core"
# `lib` — so punktfunk-host / punktfunk-client-rs / tools link it as a normal Rust crate.
# `staticlib` — `libpunktfunk_core.a` for the C test harness and static embedding.
# `cdylib` — `libpunktfunk_core.{so,dylib}` for Swift/Kotlin clients via the C ABI.
crate-type = ["lib", "cdylib", "staticlib"]
[features]
default = []
# Control-plane QUIC (pairing, config, reverse audio). tokio is permitted ONLY here,
# never on the per-frame hot path. Off by default so the core stays runtime-free.
quic = ["dep:quinn", "dep:tokio", "dep:rustls", "dep:rcgen", "dep:rustls-pki-types", "dep:sha2", "dep:hmac", "dep:spake2"]
[dependencies]
reed-solomon-simd = "3.1" # GF(2^16) Leopard-RS, SIMD, O(n log n) — the wall-breaker (P2)
# Vendored fork of fec-rs: GF(2^8) classic RS with the *Cauchy* generator matrix
# (M[j][i] = inv[(m+i)^j]) — byte-identical to the `nanors` library Moonlight uses, so our
# parity is decodable by a stock Moonlight client. (reed-solomon-erasure is Vandermonde and is
# NOT interoperable.) See vendor/fec-rs/LICENSE (BSD-2-Clause).
fec-rs = { path = "vendor/fec-rs" }
aes-gcm = "0.10" # AES-128-GCM session crypto, matches GameStream
zerocopy = { version = "0.8", features = ["derive"] }
bytes = "1"
socket2 = "0.6" # set SO_SNDBUF/SO_RCVBUF — default UDP buffers are too small for 4K/5K frame bursts
thiserror = "2"
tracing = { version = "0.1", default-features = false, features = ["std"] }
rand = "0.9"
zeroize = "1"
quinn = { version = "0.11", optional = true }
rustls = { version = "0.23", optional = true, default-features = false, features = ["ring", "std"] }
rcgen = { version = "0.13", optional = true, default-features = false, features = ["aws_lc_rs", "pem"] }
rustls-pki-types = { version = "1", optional = true }
sha2 = { version = "0.10", optional = true }
hmac = { version = "0.12", optional = true }
spake2 = { version = "0.4", optional = true }
tokio = { version = "1", optional = true, features = ["rt-multi-thread", "net", "sync", "macros"] }
[dev-dependencies]
proptest = "1"
[build-dependencies]
cbindgen = "0.29"