48 lines
862 B
Go
48 lines
862 B
Go
package jsonparser
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import (
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bio "bytes"
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)
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// minInt64 '-9223372036854775808' is the smallest representable number in int64
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const minInt64 = `9223372036854775808`
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// About 2x faster then strconv.ParseInt because it only supports base 10, which is enough for JSON
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func parseInt(bytes []byte) (v int64, ok bool, overflow bool) {
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if len(bytes) == 0 {
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return 0, false, false
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}
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var neg bool = false
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if bytes[0] == '-' {
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neg = true
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bytes = bytes[1:]
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}
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var b int64 = 0
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for _, c := range bytes {
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if c >= '0' && c <= '9' {
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b = (10 * v) + int64(c-'0')
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} else {
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return 0, false, false
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}
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if overflow = (b < v); overflow {
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break
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}
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v = b
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}
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if overflow {
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if neg && bio.Equal(bytes, []byte(minInt64)) {
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return b, true, false
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}
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return 0, false, true
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}
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if neg {
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return -v, true, false
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} else {
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return v, true, false
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}
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}
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