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package jsonparser
const absMinInt64 = 1 << 63
const maxInt64 = 1<<63 - 1
const maxUint64 = 1<<64 - 1
// About 2x faster then strconv.ParseInt because it only supports base 10, which is enough for JSON
func parseInt(bytes []byte) (v int64, ok bool, overflow bool) {
if len(bytes) == 0 {
return 0, false, false
}
var neg bool = false
if bytes[0] == '-' {
neg = true
bytes = bytes[1:]
}
var n uint64 = 0
for _, c := range bytes {
if c < '0' || c > '9' {
return 0, false, false
}
if n > maxUint64/10 {
return 0, false, true
}
n *= 10
n1 := n + uint64(c-'0')
if n1 < n {
return 0, false, true
}
n = n1
}
if n > maxInt64 {
if neg && n == absMinInt64 {
return -absMinInt64, true, false
}
return 0, false, true
}
if neg {
return -int64(n), true, false
} else {
return int64(n), true, false
}
}
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