mram
8fccd333aa
- diffConfig reports the env var names (from new struct tags) instead of Go field names, so the reload-env reply names what the user can change - the monitor's GPU line now shows the game detector's last finding (external holders or none) and how long ago the check ran - control channel: 10s per-connection watchdog (abortive force-close), cap of 32 concurrent connections, reload-env rate-limited; command read was already capped at 4 KiB
67 lines
1.5 KiB
Go
67 lines
1.5 KiB
Go
//go:build linux
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package control
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import (
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"context"
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"log/slog"
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"net"
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"os"
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"time"
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)
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// sockPath lives in the unit's RuntimeDirectory; mode 0666 lets every
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// local user ask, nothing can reach it from off the machine.
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const sockPath = "/run/gpu-turnstile/control.sock"
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// Serve starts the socket listener in the background and returns; only a
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// setup failure is reported. Each client connection is answered in its own
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// goroutine.
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func Serve(ctx context.Context, h Handler, log *slog.Logger) error {
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os.Remove(sockPath) // stale socket from a previous run
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ln, err := net.Listen("unix", sockPath)
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if err != nil {
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return err
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}
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if err := os.Chmod(sockPath, 0o666); err != nil {
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ln.Close()
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return err
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}
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go func() {
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<-ctx.Done()
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ln.Close()
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}()
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go func() {
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for {
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c, err := ln.Accept()
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if err != nil {
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return // shutting down
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}
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uc := unixConn{c}
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if !serve(uc, h) {
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uc.ForceClose()
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}
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}
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}()
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return nil
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}
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// unixConn adds an abortive ForceClose to net.Conn: a deadline in the
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// past fails pending and future I/O immediately.
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type unixConn struct{ net.Conn }
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func (c unixConn) ForceClose() error {
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c.SetDeadline(time.Now().Add(-time.Second)) //nolint:errcheck // best effort
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return c.Conn.Close()
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}
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// Ask sends one command to the running service and returns its reply.
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func Ask(cmd string) (string, error) {
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c, err := net.DialTimeout("unix", sockPath, 2*time.Second)
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if err != nil {
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return "", ErrUnavailable
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}
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defer c.Close()
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return readReply(c, cmd)
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}
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