About 2x faster then strconv.ParseInt because it only supports base 10, which is enough for JSON
(bytes []byte)
| 7 | |
| 8 | // About 2x faster then strconv.ParseInt because it only supports base 10, which is enough for JSON |
| 9 | func parseInt(bytes []byte) (v int64, ok bool, overflow bool) { |
| 10 | l := len(bytes) |
| 11 | if l == 0 { |
| 12 | return 0, false, false |
| 13 | } |
| 14 | |
| 15 | var neg bool = false |
| 16 | i := 0 |
| 17 | if bytes[0] == '-' { |
| 18 | neg = true |
| 19 | i = 1 |
| 20 | } |
| 21 | |
| 22 | if l-i < 19 { |
| 23 | for ; i < l; i++ { |
| 24 | d := bytes[i] - '0' |
| 25 | if d > 9 { |
| 26 | return 0, false, false |
| 27 | } |
| 28 | v = 10*v + int64(d) |
| 29 | } |
| 30 | |
| 31 | if neg { |
| 32 | return -v, true, false |
| 33 | } |
| 34 | return v, true, false |
| 35 | } |
| 36 | |
| 37 | if neg { |
| 38 | bytes = bytes[1:] |
| 39 | } |
| 40 | |
| 41 | var n uint64 = 0 |
| 42 | for _, c := range bytes { |
| 43 | if c < '0' || c > '9' { |
| 44 | return 0, false, false |
| 45 | } |
| 46 | if n > maxUint64/10 { |
| 47 | return 0, false, true |
| 48 | } |
| 49 | n *= 10 |
| 50 | n1 := n + uint64(c-'0') |
| 51 | if n1 < n { |
| 52 | return 0, false, true |
| 53 | } |
| 54 | n = n1 |
| 55 | } |
| 56 | |
| 57 | if n > maxInt64 { |
| 58 | if neg && n == absMinInt64 { |
| 59 | return -absMinInt64, true, false |
| 60 | } |
| 61 | return 0, false, true |
| 62 | } |
| 63 | |
| 64 | if neg { |
| 65 | return -int64(n), true, false |
| 66 | } else { |
no outgoing calls