42 lines
1.1 KiB
Go
42 lines
1.1 KiB
Go
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// Copyright 2017 The Go Authors. All rights reserved.
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// Use of this source code is governed by a BSD-style
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// license that can be found in the LICENSE file.
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package objabi
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import "strings"
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// PathToPrefix converts raw string to the prefix that will be used in the
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// symbol table. All control characters, space, '%' and '"', as well as
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// non-7-bit clean bytes turn into %xx. The period needs escaping only in the
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// last segment of the path, and it makes for happier users if we escape that as
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// little as possible.
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func PathToPrefix(s string) string {
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slash := strings.LastIndex(s, "/")
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// check for chars that need escaping
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n := 0
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for r := 0; r < len(s); r++ {
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if c := s[r]; c <= ' ' || (c == '.' && r > slash) || c == '%' || c == '"' || c >= 0x7F {
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n++
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}
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}
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// quick exit
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if n == 0 {
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return s
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}
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// escape
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const hex = "0123456789abcdef"
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p := make([]byte, 0, len(s)+2*n)
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for r := 0; r < len(s); r++ {
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if c := s[r]; c <= ' ' || (c == '.' && r > slash) || c == '%' || c == '"' || c >= 0x7F {
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p = append(p, '%', hex[c>>4], hex[c&0xF])
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} else {
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p = append(p, c)
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}
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}
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return string(p)
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}
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