src/go/plugin/go.d/agent/confgroup/cache.go
// SPDX-License-Identifier: GPL-3.0-or-later
package confgroup
func NewCache() *Cache {
return &Cache{
hashes: make(map[uint64]uint),
sources: make(map[string]map[uint64]Config),
}
}
type Cache struct {
hashes map[uint64]uint // map[cfgHash]cfgCount
sources map[string]map[uint64]Config // map[cfgSource]map[cfgHash]cfg
}
func (c *Cache) Add(group *Group) (added, removed []Config) {
if group == nil {
return nil, nil
}
if len(group.Configs) == 0 {
return c.addEmpty(group)
}
return c.addNotEmpty(group)
}
func (c *Cache) addEmpty(group *Group) (added, removed []Config) {
set, ok := c.sources[group.Source]
if !ok {
return nil, nil
}
for hash, cfg := range set {
c.hashes[hash]--
if c.hashes[hash] == 0 {
removed = append(removed, cfg)
}
delete(set, hash)
}
delete(c.sources, group.Source)
return nil, removed
}
func (c *Cache) addNotEmpty(group *Group) (added, removed []Config) {
set, ok := c.sources[group.Source]
if !ok {
set = make(map[uint64]Config)
c.sources[group.Source] = set
}
seen := make(map[uint64]struct{})
for _, cfg := range group.Configs {
hash := cfg.Hash()
seen[hash] = struct{}{}
if _, ok := set[hash]; ok {
continue
}
set[hash] = cfg
if c.hashes[hash] == 0 {
added = append(added, cfg)
}
c.hashes[hash]++
}
if !ok {
return added, nil
}
for hash, cfg := range set {
if _, ok := seen[hash]; ok {
continue
}
delete(set, hash)
c.hashes[hash]--
if c.hashes[hash] == 0 {
removed = append(removed, cfg)
}
}
if len(set) == 0 {
delete(c.sources, group.Source)
}
return added, removed
}