lotus/chain/events/events_height.go
2019-09-18 13:01:52 +02:00

120 lines
2.5 KiB
Go

package events
import (
"sync"
"github.com/filecoin-project/go-lotus/chain/types"
)
type heightEvents struct {
lk sync.Mutex
tsc *tipSetCache
gcConfidence uint64
ctr triggerId
heightTriggers map[triggerId]*heightHandler
htTriggerHeights map[triggerH][]triggerId
htHeights map[msgH][]triggerId
}
func (e *heightEvents) headChangeAt(rev, app []*types.TipSet) error {
e.lk.Lock()
defer e.lk.Unlock()
// highest tipset is always the first (see api.ReorgOps)
newH := app[0].Height()
for _, ts := range rev {
// TODO: log error if h below gcconfidence
// revert height-based triggers
for _, tid := range e.htHeights[ts.Height()] {
// don't revert if newH is above this ts
if newH >= ts.Height() {
continue
}
err := e.heightTriggers[tid].revert(ts)
if err != nil {
log.Errorf("reverting chain trigger (@H %d): %s", ts.Height(), err)
}
}
if err := e.tsc.revert(ts); err != nil {
return err
}
}
tail := len(app) - 1
for i := range app {
ts := app[tail-i]
if err := e.tsc.add(ts); err != nil {
return err
}
// height triggers
for _, tid := range e.htTriggerHeights[ts.Height()] {
hnd := e.heightTriggers[tid]
triggerH := ts.Height() - uint64(hnd.confidence)
incTs, err := e.tsc.get(triggerH)
if err != nil {
return err
}
if err := hnd.handle(incTs, ts.Height()); err != nil {
msgInfo := ""
log.Errorf("chain trigger (%s@H %d, called @ %d) failed: %s", msgInfo, triggerH, ts.Height(), err)
}
}
}
return nil
}
// ChainAt invokes the specified `HeightHandler` when the chain reaches the
// specified height+confidence threshold. If the chain is rolled-back under the
// specified height, `RevertHandler` will be called.
func (e *heightEvents) ChainAt(hnd HeightHandler, rev RevertHandler, confidence int, h uint64) error {
e.lk.Lock()
defer e.lk.Unlock()
bestH := e.tsc.best().Height()
if bestH >= h+uint64(confidence) {
ts, err := e.tsc.get(h)
if err != nil {
log.Warnf("events.ChainAt: calling HandleFunc with nil tipset, not found in cache: %s", err)
}
if err := hnd(ts, bestH); err != nil {
return err
}
}
if bestH >= h+uint64(confidence)+e.gcConfidence {
return nil
}
triggerAt := h + uint64(confidence)
id := e.ctr
e.ctr++
e.heightTriggers[id] = &heightHandler{
confidence: confidence,
handle: hnd,
revert: rev,
}
e.htHeights[h] = append(e.htHeights[h], id)
e.htTriggerHeights[triggerAt] = append(e.htTriggerHeights[triggerAt], id)
return nil
}