Add invopop/jsonschema fork

vendor/github.com/buger/jsonparser/bytes.go

@@ -0,0 +1,47 @@
+package jsonparser
+
+import (
+	bio "bytes"
+)
+
+// minInt64 '-9223372036854775808' is the smallest representable number in int64
+const minInt64 = `9223372036854775808`
+
+// 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 b int64 = 0
+	for _, c := range bytes {
+		if c >= '0' && c <= '9' {
+			b = (10 * v) + int64(c-'0')
+		} else {
+			return 0, false, false
+		}
+		if overflow = (b < v); overflow {
+			break
+		}
+		v = b
+	}
+
+	if overflow {
+		if neg && bio.Equal(bytes, []byte(minInt64)) {
+			return b, true, false
+		}
+		return 0, false, true
+	}
+
+	if neg {
+		return -v, true, false
+	} else {
+		return v, true, false
+	}
+}