42 lines
760 B
Go
42 lines
760 B
Go
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// Copyright 2015 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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// -build !amd64,!s390x
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package bytes
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// TODO: implements short string optimization on non amd64 platforms
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// and get rid of bytes_amd64.go
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// Index returns the index of the first instance of sep in s, or -1 if sep is not present in s.
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func Index(s, sep []byte) int {
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n := len(sep)
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if n == 0 {
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return 0
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}
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if n > len(s) {
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return -1
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}
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c := sep[0]
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if n == 1 {
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return IndexByte(s, c)
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}
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i := 0
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t := s[:len(s)-n+1]
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for i < len(t) {
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if t[i] != c {
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o := IndexByte(t[i:], c)
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if o < 0 {
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break
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}
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i += o
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}
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if Equal(s[i:i+n], sep) {
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return i
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}
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i++
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}
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return -1
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}
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