neoneo-go/pkg/core/cache.go
Roman Khimov b263c97bbb core: add some mechanism to drop bad blocks from cache
If we can't persist anything from our cache there is something wrong with
it. Try to remediate some possible problems.
2019-09-16 16:26:30 +03:00

87 lines
1.9 KiB
Go

package core
import (
"sync"
"github.com/CityOfZion/neo-go/pkg/util"
)
// Cache is data structure with fixed type key of Uint256, but has a
// generic value. Used for block, tx and header cache types.
type Cache struct {
lock sync.RWMutex
m map[util.Uint256]interface{}
}
// NewCache returns a ready to use Cache object.
func NewCache() *Cache {
return &Cache{
m: make(map[util.Uint256]interface{}),
}
}
// GetBlock will return a Block type from the cache.
func (c *Cache) GetBlock(h util.Uint256) (block *Block, ok bool) {
c.lock.RLock()
defer c.lock.RUnlock()
return c.getBlock(h)
}
func (c *Cache) getBlock(h util.Uint256) (block *Block, ok bool) {
if v, b := c.m[h]; b {
block, ok = v.(*Block)
return
}
return
}
// Add adds the given hash along with its value to the cache.
func (c *Cache) Add(h util.Uint256, v interface{}) {
c.lock.Lock()
defer c.lock.Unlock()
c.add(h, v)
}
func (c *Cache) add(h util.Uint256, v interface{}) {
c.m[h] = v
}
func (c *Cache) has(h util.Uint256) bool {
_, ok := c.m[h]
return ok
}
// Has returns whether the cache contains the given hash.
func (c *Cache) Has(h util.Uint256) bool {
c.lock.Lock()
defer c.lock.Unlock()
return c.has(h)
}
// Len return the number of items present in the cache.
func (c *Cache) Len() int {
c.lock.RLock()
defer c.lock.RUnlock()
return len(c.m)
}
// Delete removes the item out of the cache.
func (c *Cache) Delete(h util.Uint256) {
c.lock.Lock()
defer c.lock.Unlock()
delete(c.m, h)
}
// ReapStrangeBlocks drops blocks from cache that don't fit into the
// blkHeight-headHeight interval. Cache should only contain blocks that we
// expect to get and store.
func (c *Cache) ReapStrangeBlocks(blkHeight, headHeight uint32) {
c.lock.Lock()
defer c.lock.Unlock()
for i, b := range c.m {
block, ok := b.(*Block)
if ok && (block.Index < blkHeight || block.Index > headHeight) {
delete(c.m, i)
}
}
}