caddy/modules/caddyhttp/reverseproxy/ascii.go
Francis Lavoie e4ce40f8ff
reverseproxy: Sync up handleUpgradeResponse with stdlib (#4664)
* reverseproxy: Sync up `handleUpgradeResponse` with stdlib

I had left this as a TODO for when we bump to minimum 1.17, but I should've realized it was under `internal` so it couldn't be used directly.

Copied the functions we needed for parity. Hopefully this is ok!

* Add tests and fix godoc comments

Co-authored-by: Matthew Holt <mholt@users.noreply.github.com>
2022-04-11 12:49:56 -06:00

57 lines
1.8 KiB
Go

// Copyright 2015 Matthew Holt and The Caddy Authors
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
// Most of the code in this file was initially borrowed from the Go
// standard library and modified; It had this copyright notice:
// Copyright 2021 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
// Original source, copied because the package was marked internal:
// https://github.com/golang/go/blob/5c489514bc5e61ad9b5b07bd7d8ec65d66a0512a/src/net/http/internal/ascii/print.go
package reverseproxy
// asciiEqualFold is strings.EqualFold, ASCII only. It reports whether s and t
// are equal, ASCII-case-insensitively.
func asciiEqualFold(s, t string) bool {
if len(s) != len(t) {
return false
}
for i := 0; i < len(s); i++ {
if asciiLower(s[i]) != asciiLower(t[i]) {
return false
}
}
return true
}
// asciiLower returns the ASCII lowercase version of b.
func asciiLower(b byte) byte {
if 'A' <= b && b <= 'Z' {
return b + ('a' - 'A')
}
return b
}
// asciiIsPrint returns whether s is ASCII and printable according to
// https://tools.ietf.org/html/rfc20#section-4.2.
func asciiIsPrint(s string) bool {
for i := 0; i < len(s); i++ {
if s[i] < ' ' || s[i] > '~' {
return false
}
}
return true
}