45 lines
1.2 KiB
Go
45 lines
1.2 KiB
Go
// +build !appengine,!appenginevm
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package jsonparser
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import (
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"reflect"
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"strconv"
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"unsafe"
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"runtime"
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)
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//
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// The reason for using *[]byte rather than []byte in parameters is an optimization. As of Go 1.6,
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// the compiler cannot perfectly inline the function when using a non-pointer slice. That is,
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// the non-pointer []byte parameter version is slower than if its function body is manually
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// inlined, whereas the pointer []byte version is equally fast to the manually inlined
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// version. Instruction count in assembly taken from "go tool compile" confirms this difference.
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//
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// TODO: Remove hack after Go 1.7 release
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//
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func equalStr(b *[]byte, s string) bool {
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return *(*string)(unsafe.Pointer(b)) == s
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}
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func parseFloat(b *[]byte) (float64, error) {
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return strconv.ParseFloat(*(*string)(unsafe.Pointer(b)), 64)
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}
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// A hack until issue golang/go#2632 is fixed.
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// See: https://github.com/golang/go/issues/2632
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func bytesToString(b *[]byte) string {
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return *(*string)(unsafe.Pointer(b))
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}
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func StringToBytes(s string) []byte {
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b := make([]byte, 0, 0)
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bh := (*reflect.SliceHeader)(unsafe.Pointer(&b))
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sh := (*reflect.StringHeader)(unsafe.Pointer(&s))
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bh.Data = sh.Data
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bh.Cap = sh.Len
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bh.Len = sh.Len
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runtime.KeepAlive(s)
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return b
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}
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