45 lines
		
	
	
		
			869 B
		
	
	
	
		
			Go
		
	
	
	
			
		
		
	
	
			45 lines
		
	
	
		
			869 B
		
	
	
	
		
			Go
		
	
	
	
| // Copyright 2022 The Gitea Authors. All rights reserved.
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| // SPDX-License-Identifier: MIT
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| 
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| package regexplru
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| 
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| import (
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| 	"regexp"
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| 
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| 	"code.gitea.io/gitea/modules/log"
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| 
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| 	lru "github.com/hashicorp/golang-lru/v2"
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| )
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| 
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| var lruCache *lru.Cache[string, any]
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| 
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| func init() {
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| 	var err error
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| 	lruCache, err = lru.New[string, any](1000)
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| 	if err != nil {
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| 		log.Fatal("failed to new LRU cache, err: %v", err)
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| 	}
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| }
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| 
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| // GetCompiled works like regexp.Compile, the compiled expr or error is stored in LRU cache
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| func GetCompiled(expr string) (r *regexp.Regexp, err error) {
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| 	v, ok := lruCache.Get(expr)
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| 	if !ok {
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| 		r, err = regexp.Compile(expr)
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| 		if err != nil {
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| 			lruCache.Add(expr, err)
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| 			return nil, err
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| 		}
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| 		lruCache.Add(expr, r)
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| 	} else {
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| 		r, ok = v.(*regexp.Regexp)
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| 		if !ok {
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| 			if err, ok = v.(error); ok {
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| 				return nil, err
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| 			}
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| 			panic("impossible")
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| 		}
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| 	}
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| 	return r, nil
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| }
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