| 1 | package hostguard |
| 2 | |
| 3 | import ( |
| 4 | "context" |
| 5 | "github.com/carlosframework/platform/internal/hostclaim" |
| 6 | ) |
| 7 | |
| 8 | func (g Guard) BeginColdHandover(ctx context.Context, prior, barrier FenceTarget, check func(*hostclaim.Claim) error) error { |
| 9 | return g.beginColdHandover(ctx, prior, barrier, nil, check) |
| 10 | } |
| 11 | |
| 12 | func (g Guard) BeginServingHandover(ctx context.Context, prior, barrier FenceTarget, installation RootInstallation, check func(*hostclaim.Claim) error) error { |
| 13 | if g.Root == nil || prior.Op != "" || prior.Phase != "" || prior.ObligationID != "" || barrier.Op != "" || barrier.Phase != "" || barrier.ObligationID != "" || installation.Empty || installation.Host != prior.Host || installation.Incarnation != prior.Incarnation || installation.Stamp != prior.Stamp || installation.Box != prior.Box || installation.Enrollment != prior.Enrollment || installation.InventoryRevision == 0 { |
| 14 | return ErrInvalidInput |
| 15 | } |
| 16 | return g.beginColdHandover(ctx, prior, barrier, &installation, check) |
| 17 | } |
| 18 | |
| 19 | func (g Guard) beginColdHandover(ctx context.Context, prior, barrier FenceTarget, installation *RootInstallation, check func(*hostclaim.Claim) error) error { |
| 20 | return g.locked(ctx, prior.Host, func(d *recordDir) error { |
| 21 | if ((installation == nil || prior.Session != 0) && prior.validate(prior.Host) != nil) || barrier.validate(prior.Host) != nil || prior.Host != barrier.Host || prior.Incarnation != barrier.Incarnation || barrier.Stamp <= prior.Stamp || barrier.Session <= prior.Session || barrier.Stamp != barrier.Session || check == nil { |
| 22 | return ErrInvalidInput |
| 23 | } |
| 24 | claim, err := g.fresh(ctx, prior.Host) |
| 25 | if err != nil { |
| 26 | return err |
| 27 | } |
| 28 | if err = check(claim); err != nil { |
| 29 | return err |
| 30 | } |
| 31 | if !barrier.matchesSession(claim, Captured{Incarnation: barrier.Incarnation, Stamp: barrier.Stamp}) { |
| 32 | return ErrFenceTarget |
| 33 | } |
| 34 | r, err := d.read(prior.Host) |
| 35 | if err != nil { |
| 36 | return err |
| 37 | } |
| 38 | if installation != nil && (r.installation != *installation || r.quarantined || r.pendingInstallation != nil) { |
| 39 | return ErrRecordIncarnation |
| 40 | } |
| 41 | found := false |
| 42 | for _, receipt := range r.FenceJournal { |
| 43 | if receipt.Target == prior { |
| 44 | found = true |
| 45 | } |
| 46 | } |
| 47 | if !found && (installation == nil || prior.Session != 0) { |
| 48 | return ErrNoFenceReceipt |
| 49 | } |
| 50 | if installation != nil && prior.Session == 0 && (prior.FenceID != "" || (r.ActiveFence != nil && *r.ActiveFence != barrier)) { |
| 51 | return ErrFenceTarget |
| 52 | } |
| 53 | if r.ActiveFence != nil && *r.ActiveFence == barrier { |
| 54 | return d.sync(prior.Host) |
| 55 | } |
| 56 | if r.Incarnation != prior.Incarnation || (r.ActiveStamp != 0 && r.ActiveStamp != prior.Stamp) { |
| 57 | return ErrStampMismatch |
| 58 | } |
| 59 | if r.ActiveFence != nil && *r.ActiveFence != prior { |
| 60 | return ErrFenceActive |
| 61 | } |
| 62 | copied := barrier |
| 63 | r.ActiveFence = &copied |
| 64 | if r.root { |
| 65 | r.barrier = &copied |
| 66 | } |
| 67 | return d.write(r) |
| 68 | }) |
| 69 | } |
| 70 | func (g Guard) CompleteColdHandover(ctx context.Context, barrier FenceTarget, alreadyComplete bool, check func(*hostclaim.Claim) error, fn func() error) error { |
| 71 | return g.locked(ctx, barrier.Host, func(d *recordDir) error { |
| 72 | claim, err := g.fresh(ctx, barrier.Host) |
| 73 | if err != nil { |
| 74 | return err |
| 75 | } |
| 76 | if check == nil || fn == nil { |
| 77 | return ErrInvalidInput |
| 78 | } |
| 79 | if err = check(claim); err != nil { |
| 80 | return err |
| 81 | } |
| 82 | r, err := d.read(barrier.Host) |
| 83 | if err != nil { |
| 84 | return err |
| 85 | } |
| 86 | if alreadyComplete && r.Incarnation == barrier.Incarnation && r.ActiveStamp == barrier.Stamp && r.ActiveFence == nil { |
| 87 | if g.Root == nil { |
| 88 | return d.sync(barrier.Host) |
| 89 | } |
| 90 | if err := g.refreshRootInventory(ctx, &r); err != nil { |
| 91 | return err |
| 92 | } |
| 93 | return d.write(r) |
| 94 | } |
| 95 | if r.ActiveFence == nil || *r.ActiveFence != barrier || r.Incarnation != barrier.Incarnation { |
| 96 | return ErrFenceTarget |
| 97 | } |
| 98 | if err = fn(); err != nil { |
| 99 | return err |
| 100 | } |
| 101 | if r.ActiveStamp != barrier.Stamp { |
| 102 | r.retire() |
| 103 | r.ActiveStamp = barrier.Stamp |
| 104 | } |
| 105 | r.ActiveFence = nil |
| 106 | r.barrier = nil |
| 107 | if err := g.refreshRootInventory(ctx, &r); err != nil { |
| 108 | return err |
| 109 | } |
| 110 | return d.write(r) |
| 111 | }) |
| 112 | } |
| 113 | |
| 114 | func (g Guard) CompletedColdPredecessor(ctx context.Context, host string, captured Captured, session uint64, op, phase string) (FenceReceipt, error) { |
| 115 | var found FenceReceipt |
| 116 | err := g.fenceLocked(ctx, host, captured, func(d *recordDir) error { |
| 117 | r, err := d.read(host) |
| 118 | if err != nil { |
| 119 | return err |
| 120 | } |
| 121 | if r.root && r.ActiveFence != nil { |
| 122 | t := *r.ActiveFence |
| 123 | if t.Host == host && t.Incarnation == captured.Incarnation && t.Stamp == captured.Stamp && t.Session == session && t.Op == op && t.Phase == phase { |
| 124 | for _, receipt := range r.FenceJournal { |
| 125 | if receipt.Target == t { |
| 126 | found = receipt |
| 127 | return nil |
| 128 | } |
| 129 | } |
| 130 | return ErrNoFenceReceipt |
| 131 | } |
| 132 | } |
| 133 | for _, receipt := range r.FenceJournal { |
| 134 | t := receipt.Target |
| 135 | if t.Host == host && t.Incarnation == captured.Incarnation && t.Stamp == captured.Stamp && t.Session == session && t.Op == op && t.Phase == phase { |
| 136 | if found.Target.FenceID != "" && found.Target != t { |
| 137 | return ErrFenceTarget |
| 138 | } |
| 139 | found = receipt |
| 140 | } |
| 141 | } |
| 142 | if found.Target.FenceID == "" { |
| 143 | return ErrNoFenceReceipt |
| 144 | } |
| 145 | return nil |
| 146 | }) |
| 147 | return found, err |
| 148 | } |
| 149 | |
| 150 | func (g Guard) AbandonColdHandover(ctx context.Context, barrier FenceTarget) error { |
| 151 | if g.Root == nil { |
| 152 | return ErrUnsupported |
| 153 | } |
| 154 | return g.readLocked(ctx, barrier.Host, func(d *recordDir) error { |
| 155 | c, err := g.fresh(ctx, barrier.Host) |
| 156 | if err != nil { |
| 157 | return err |
| 158 | } |
| 159 | if c.Holder.Incarnation == barrier.Incarnation && (c.Holder.Stamp < barrier.Stamp || c.Holder.Session <= barrier.Session) { |
| 160 | return ErrFenced |
| 161 | } |
| 162 | r, err := d.read(barrier.Host) |
| 163 | if err != nil { |
| 164 | return err |
| 165 | } |
| 166 | if r.barrier == nil { |
| 167 | return nil |
| 168 | } |
| 169 | if *r.barrier != barrier { |
| 170 | return ErrFenceTarget |
| 171 | } |
| 172 | r.rootRetired = append(r.rootRetired, Captured{Incarnation: barrier.Incarnation, Stamp: barrier.Stamp}) |
| 173 | r.barrier = nil |
| 174 | if r.ActiveFence != nil && *r.ActiveFence == barrier { |
| 175 | r.ActiveFence = nil |
| 176 | } |
| 177 | return d.write(r) |
| 178 | }) |
| 179 | } |
| 180 | |
| 181 | // SettleObsoleteColdHandover settles an interrupted cold handover from prior |
| 182 | // whose journaled successor root found obsolete at startup: stamped under a |
| 183 | // box binding other than the one in root's startup roster read (roster |
| 184 | // binding B3). It is fenced: it runs under the host lock every handover step |
| 185 | // takes, and only for a prior whose completed fence receipt this record |
| 186 | // holds. It needs no claim session advance, unlike AbandonColdHandover: the |
| 187 | // trigger is the binding change, decided by root from its own roster read. |
| 188 | // |
| 189 | // It undoes BeginColdHandover: the barrier is cleared and the deny slot it |
| 190 | // took goes back to the prior's completed fence, the state the prior's stop |
| 191 | // left. It records the successor's stamp as retired so it is never |
| 192 | // installed or reused, and then runs record, which persists the settlement |
| 193 | // in the handover's own journal. The prior keeps its historical cleanup |
| 194 | // authority: its stamp stays the active one, its completed fence and |
| 195 | // receipt stay, so its cleanup stop and retirement still complete. Settling |
| 196 | // again, with the barrier already cleared, only re-runs record. |
| 197 | func (g Guard) SettleObsoleteColdHandover(ctx context.Context, prior, barrier FenceTarget, record func() error) error { |
| 198 | if g.Root == nil { |
| 199 | return ErrUnsupported |
| 200 | } |
| 201 | if record == nil || prior.validate(prior.Host) != nil || barrier.validate(prior.Host) != nil || prior.Host != barrier.Host || prior.Incarnation != barrier.Incarnation || barrier.Stamp <= prior.Stamp || barrier.Session <= prior.Session || barrier.Stamp != barrier.Session { |
| 202 | return ErrInvalidInput |
| 203 | } |
| 204 | return g.locked(ctx, prior.Host, func(d *recordDir) error { |
| 205 | r, err := d.read(prior.Host) |
| 206 | if err != nil { |
| 207 | return err |
| 208 | } |
| 209 | successor := Captured{Incarnation: barrier.Incarnation, Stamp: barrier.Stamp} |
| 210 | retired := false |
| 211 | for _, old := range r.rootRetired { |
| 212 | if old == successor { |
| 213 | retired = true |
| 214 | } |
| 215 | } |
| 216 | // Already settled: only the journal's record may be missing. Whatever |
| 217 | // happened to the host since (a new successor, a new stop) stands. |
| 218 | if retired && r.barrier == nil && (r.ActiveFence == nil || *r.ActiveFence != barrier) { |
| 219 | return record() |
| 220 | } |
| 221 | found := false |
| 222 | for _, receipt := range r.FenceJournal { |
| 223 | if receipt.Target == prior { |
| 224 | found = true |
| 225 | } |
| 226 | } |
| 227 | if !found { |
| 228 | return ErrNoFenceReceipt |
| 229 | } |
| 230 | if r.Incarnation != prior.Incarnation || r.ActiveStamp != prior.Stamp { |
| 231 | return ErrStampMismatch |
| 232 | } |
| 233 | if r.barrier != nil && *r.barrier != barrier || r.ActiveFence != nil && *r.ActiveFence != barrier && *r.ActiveFence != prior { |
| 234 | return ErrFenceTarget |
| 235 | } |
| 236 | if !retired { |
| 237 | r.rootRetired = append(r.rootRetired, successor) |
| 238 | } |
| 239 | r.barrier = nil |
| 240 | if r.ActiveFence != nil && *r.ActiveFence == barrier { |
| 241 | restored := prior |
| 242 | r.ActiveFence = &restored |
| 243 | } |
| 244 | if err := d.write(r); err != nil { |
| 245 | return err |
| 246 | } |
| 247 | return record() |
| 248 | }) |
| 249 | } |
| 250 | |
amadan