k8s.io/apiserver@v0.31.1/pkg/storage/cacher/util.go (about)

     1  /*
     2  Copyright 2015 The Kubernetes Authors.
     3  
     4  Licensed under the Apache License, Version 2.0 (the "License");
     5  you may not use this file except in compliance with the License.
     6  You may obtain a copy of the License at
     7  
     8      http://www.apache.org/licenses/LICENSE-2.0
     9  
    10  Unless required by applicable law or agreed to in writing, software
    11  distributed under the License is distributed on an "AS IS" BASIS,
    12  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    13  See the License for the specific language governing permissions and
    14  limitations under the License.
    15  */
    16  
    17  package cacher
    18  
    19  import (
    20  	"strings"
    21  )
    22  
    23  // hasPathPrefix returns true if the string matches pathPrefix exactly, or if is prefixed with pathPrefix at a path segment boundary
    24  func hasPathPrefix(s, pathPrefix string) bool {
    25  	// Short circuit if s doesn't contain the prefix at all
    26  	if !strings.HasPrefix(s, pathPrefix) {
    27  		return false
    28  	}
    29  
    30  	pathPrefixLength := len(pathPrefix)
    31  
    32  	if len(s) == pathPrefixLength {
    33  		// Exact match
    34  		return true
    35  	}
    36  	if strings.HasSuffix(pathPrefix, "/") {
    37  		// pathPrefix already ensured a path segment boundary
    38  		return true
    39  	}
    40  	if s[pathPrefixLength:pathPrefixLength+1] == "/" {
    41  		// The next character in s is a path segment boundary
    42  		// Check this instead of normalizing pathPrefix to avoid allocating on every call
    43  		return true
    44  	}
    45  	return false
    46  }