refactor(network): consolidate network change monitoring

Remove separate watchLinkState function and integrate link state change
handling directly into monitorNetworkChanges. This consolidates network
monitoring logic into a single place and simplifies the codebase.

Update netlink dependency from v1.2.1-beta.2 to v1.3.1 and netns from
v0.0.4 to v0.0.5 to use stable versions.

cmd/cli/dns_proxy.go

@@ -1530,6 +1530,11 @@ func (p *prog) monitorNetworkChanges(ctx context.Context) error {
 			return
 		}
 
+		p.Debug().Msg("Link state changed, re-bootstrapping")
+		for _, uc := range p.cfg.Upstream {
+			uc.ReBootstrap(ctrld.LoggerCtx(ctx, p.logger.Load()))
+		}
+
 		// Get IPs from default route interface in new state
 		selfIP := p.defaultRouteIP()
 

cmd/cli/netlink_linux.go

@@ -1,36 +0,0 @@
-package cli
-
-import (
-	"context"
-
-	"github.com/vishvananda/netlink"
-	"golang.org/x/sys/unix"
-
-	"github.com/Control-D-Inc/ctrld"
-)
-
-func (p *prog) watchLinkState(ctx context.Context) {
-	ch := make(chan netlink.LinkUpdate)
-	done := make(chan struct{})
-	defer close(done)
-	if err := netlink.LinkSubscribe(ch, done); err != nil {
-		p.Warn().Err(err).Msg("Could not subscribe link")
-		return
-	}
-	for {
-		select {
-		case <-ctx.Done():
-			return
-		case lu := <-ch:
-			if lu.Change == 0xFFFFFFFF {
-				continue
-			}
-			if lu.Change&unix.IFF_UP != 0 {
-				p.Debug().Msgf("Link state changed, re-bootstrapping")
-				for _, uc := range p.cfg.Upstream {
-					uc.ReBootstrap(ctrld.LoggerCtx(ctx, p.logger.Load()))
-				}
-			}
-		}
-	}
-}

cmd/cli/netlink_others.go

@@ -1,7 +0,0 @@
-//go:build !linux
-
-package cli
-
-import "context"
-
-func (p *prog) watchLinkState(ctx context.Context) {}

cmd/cli/prog.go

@@ -515,7 +515,6 @@ func (p *prog) run(reload bool, reloadCh chan struct{}) {
 			defer wg.Done()
 			p.runClientInfoDiscover(ctx)
 		}()
-		go p.watchLinkState(ctx)
 	}
 
 	if !reload {