| 1 | // SPDX-License-Identifier: GPL-3.0-or-later |
| 2 | |
| 3 | package l2topology |
| 4 | |
| 5 | import "sync" |
| 6 | |
| 7 | // TopologyBuilderFunc builds the current topology snapshot. |
| 8 | type TopologyBuilderFunc func() (NetworkRouterTopology, error) |
| 9 | |
| 10 | // TopologyUpdater ports non-routing runtime semantics from Enlinkd TopologyUpdater. |
| 11 | type TopologyUpdater struct { |
| 12 | mu sync.RWMutex |
| 13 | |
| 14 | topology NetworkRouterTopology |
| 15 | builder TopologyBuilderFunc |
| 16 | parseFn func() bool |
| 17 | refreshFn func() |
| 18 | hasRun bool |
| 19 | forceRun bool |
| 20 | runFailed bool |
| 21 | lastFailed error |
| 22 | } |
| 23 | |
| 24 | // NewTopologyUpdater builds an updater. parseFn and refreshFn are optional. |
| 25 | func NewTopologyUpdater(builder TopologyBuilderFunc, parseFn func() bool, refreshFn func()) *TopologyUpdater { |
| 26 | if builder == nil { |
| 27 | return &TopologyUpdater{} |
| 28 | } |
| 29 | return &TopologyUpdater{ |
| 30 | builder: builder, |
| 31 | parseFn: parseFn, |
| 32 | refreshFn: refreshFn, |
| 33 | topology: NetworkRouterTopology{}, |
| 34 | } |
| 35 | } |
| 36 | |
| 37 | // RunSchedulable executes one discovery cycle. |
| 38 | func (u *TopologyUpdater) RunSchedulable() { |
| 39 | if u == nil || u.builder == nil { |
| 40 | return |
| 41 | } |
| 42 | |
| 43 | u.mu.Lock() |
| 44 | hasRun := u.hasRun |
| 45 | forceRun := u.forceRun |
| 46 | if forceRun { |
| 47 | u.forceRun = false |
| 48 | } |
| 49 | u.mu.Unlock() |
| 50 | |
| 51 | if !hasRun { |
| 52 | topology, err := u.builder() |
| 53 | u.mu.Lock() |
| 54 | defer u.mu.Unlock() |
| 55 | if err != nil { |
| 56 | u.runFailed = true |
| 57 | u.lastFailed = err |
| 58 | return |
| 59 | } |
| 60 | u.topology = CloneNetworkRouterTopology(topology) |
| 61 | u.hasRun = true |
| 62 | u.runFailed = false |
| 63 | u.lastFailed = nil |
| 64 | return |
| 65 | } |
| 66 | |
| 67 | parseUpdates := false |
| 68 | if u.parseFn != nil { |
| 69 | parseUpdates = u.parseFn() |
| 70 | } |
| 71 | if !parseUpdates && !forceRun { |
| 72 | return |
| 73 | } |
| 74 | if u.refreshFn != nil { |
| 75 | u.refreshFn() |
| 76 | } |
| 77 | |
| 78 | topology, err := u.builder() |
| 79 | u.mu.Lock() |
| 80 | defer u.mu.Unlock() |
| 81 | if err != nil { |
| 82 | u.runFailed = true |
| 83 | u.lastFailed = err |
| 84 | return |
| 85 | } |
| 86 | u.topology = CloneNetworkRouterTopology(topology) |
| 87 | u.runFailed = false |
| 88 | u.lastFailed = nil |
| 89 | } |
| 90 | |
| 91 | // GetTopology returns a non-blocking clone of the current topology. |
| 92 | func (u *TopologyUpdater) GetTopology() NetworkRouterTopology { |
| 93 | if u == nil { |
| 94 | return NetworkRouterTopology{} |
| 95 | } |
| 96 | u.mu.RLock() |
| 97 | topology := CloneNetworkRouterTopology(u.topology) |
| 98 | u.mu.RUnlock() |
| 99 | return topology |
| 100 | } |
| 101 | |
| 102 | // ForceRun requests recomputation on the next RunSchedulable call. |
| 103 | func (u *TopologyUpdater) ForceRun() { |
| 104 | if u == nil { |
| 105 | return |
| 106 | } |
| 107 | u.mu.Lock() |
| 108 | u.forceRun = true |
| 109 | u.mu.Unlock() |
| 110 | } |
| 111 | |
| 112 | // HasRun reports if the first successful run completed. |
| 113 | func (u *TopologyUpdater) HasRun() bool { |
| 114 | if u == nil { |
| 115 | return false |
| 116 | } |
| 117 | u.mu.RLock() |
| 118 | defer u.mu.RUnlock() |
| 119 | return u.hasRun |
| 120 | } |
| 121 | |
| 122 | // LastError returns the last builder error, if any. |
| 123 | func (u *TopologyUpdater) LastError() error { |
| 124 | if u == nil { |
| 125 | return nil |
| 126 | } |
| 127 | u.mu.RLock() |
| 128 | defer u.mu.RUnlock() |
| 129 | return u.lastFailed |
| 130 | } |
| 131 | |
| 132 | // CloneNetworkRouterTopology deep-copies topology structures. |
| 133 | func CloneNetworkRouterTopology(topology NetworkRouterTopology) NetworkRouterTopology { |
| 134 | out := NetworkRouterTopology{ |
| 135 | Vertices: append([]NetworkRouterVertex(nil), topology.Vertices...), |
| 136 | Edges: append([]NetworkRouterEdge(nil), topology.Edges...), |
| 137 | DefaultVertex: topology.DefaultVertex, |
| 138 | } |
| 139 | return out |
| 140 | } |