| 1 | // SPDX-License-Identifier: GPL-3.0-or-later |
| 2 | |
| 3 | package matcher |
| 4 | |
| 5 | import "sync" |
| 6 | |
| 7 | type ( |
| 8 | cachedMatcher struct { |
| 9 | matcher Matcher |
| 10 | |
| 11 | mux sync.RWMutex |
| 12 | cache map[string]bool |
| 13 | } |
| 14 | ) |
| 15 | |
| 16 | // WithCache adds cache to the matcher. |
| 17 | func WithCache(m Matcher) Matcher { |
| 18 | switch m { |
| 19 | case TRUE(), FALSE(): |
| 20 | return m |
| 21 | default: |
| 22 | return &cachedMatcher{matcher: m, cache: make(map[string]bool)} |
| 23 | } |
| 24 | } |
| 25 | |
| 26 | func (m *cachedMatcher) Match(b []byte) bool { |
| 27 | s := string(b) |
| 28 | if result, ok := m.fetch(s); ok { |
| 29 | return result |
| 30 | } |
| 31 | result := m.matcher.Match(b) |
| 32 | m.put(s, result) |
| 33 | return result |
| 34 | } |
| 35 | |
| 36 | func (m *cachedMatcher) MatchString(s string) bool { |
| 37 | if result, ok := m.fetch(s); ok { |
| 38 | return result |
| 39 | } |
| 40 | result := m.matcher.MatchString(s) |
| 41 | m.put(s, result) |
| 42 | return result |
| 43 | } |
| 44 | |
| 45 | func (m *cachedMatcher) fetch(key string) (result bool, ok bool) { |
| 46 | m.mux.RLock() |
| 47 | result, ok = m.cache[key] |
| 48 | m.mux.RUnlock() |
| 49 | return |
| 50 | } |
| 51 | |
| 52 | func (m *cachedMatcher) put(key string, result bool) { |
| 53 | m.mux.Lock() |
| 54 | m.cache[key] = result |
| 55 | m.mux.Unlock() |
| 56 | } |