Initial commit
This commit is contained in:
121
vendor/github.com/cockroachdb/pebble/internal/testkeys/strconv.go
generated
vendored
Normal file
121
vendor/github.com/cockroachdb/pebble/internal/testkeys/strconv.go
generated
vendored
Normal file
@@ -0,0 +1,121 @@
|
||||
/*
|
||||
Copyright 2013 The Perkeep Authors
|
||||
|
||||
Licensed under the Apache License, Version 2.0 (the "License");
|
||||
you may not use this file except in compliance with the License.
|
||||
You may obtain a copy of the License at
|
||||
|
||||
http://www.apache.org/licenses/LICENSE-2.0
|
||||
|
||||
Unless required by applicable law or agreed to in writing, software
|
||||
distributed under the License is distributed on an "AS IS" BASIS,
|
||||
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
|
||||
See the License for the specific language governing permissions and
|
||||
limitations under the License.
|
||||
*/
|
||||
|
||||
package testkeys
|
||||
|
||||
import (
|
||||
"strconv"
|
||||
|
||||
"github.com/cockroachdb/errors"
|
||||
)
|
||||
|
||||
// parseUintBytes is like strconv.ParseUint, but using a []byte. Use of this
|
||||
// function avoids an allocation when parsing an integer out of a []byte.
|
||||
//
|
||||
// This function is copied from go4.org/strconv.
|
||||
func parseUintBytes(s []byte, base int, bitSize int) (n uint64, err error) {
|
||||
var cutoff, maxVal uint64
|
||||
|
||||
if bitSize == 0 {
|
||||
bitSize = int(strconv.IntSize)
|
||||
}
|
||||
|
||||
s0 := s
|
||||
switch {
|
||||
case len(s) < 1:
|
||||
err = strconv.ErrSyntax
|
||||
goto Error
|
||||
|
||||
case 2 <= base && base <= 36:
|
||||
// valid base; nothing to do
|
||||
|
||||
case base == 0:
|
||||
// Look for octal, hex prefix.
|
||||
switch {
|
||||
case s[0] == '0' && len(s) > 1 && (s[1] == 'x' || s[1] == 'X'):
|
||||
base = 16
|
||||
s = s[2:]
|
||||
if len(s) < 1 {
|
||||
err = strconv.ErrSyntax
|
||||
goto Error
|
||||
}
|
||||
case s[0] == '0':
|
||||
base = 8
|
||||
default:
|
||||
base = 10
|
||||
}
|
||||
|
||||
default:
|
||||
err = errors.New("invalid base " + strconv.Itoa(base))
|
||||
goto Error
|
||||
}
|
||||
|
||||
n = 0
|
||||
cutoff = cutoff64(base)
|
||||
maxVal = 1<<uint(bitSize) - 1
|
||||
|
||||
for i := 0; i < len(s); i++ {
|
||||
var v byte
|
||||
d := s[i]
|
||||
switch {
|
||||
case '0' <= d && d <= '9':
|
||||
v = d - '0'
|
||||
case 'a' <= d && d <= 'z':
|
||||
v = d - 'a' + 10
|
||||
case 'A' <= d && d <= 'Z':
|
||||
v = d - 'A' + 10
|
||||
default:
|
||||
n = 0
|
||||
err = strconv.ErrSyntax
|
||||
goto Error
|
||||
}
|
||||
if int(v) >= base {
|
||||
n = 0
|
||||
err = strconv.ErrSyntax
|
||||
goto Error
|
||||
}
|
||||
|
||||
if n >= cutoff {
|
||||
// n*base overflows
|
||||
n = 1<<64 - 1
|
||||
err = strconv.ErrRange
|
||||
goto Error
|
||||
}
|
||||
n *= uint64(base)
|
||||
|
||||
n1 := n + uint64(v)
|
||||
if n1 < n || n1 > maxVal {
|
||||
// n+v overflows
|
||||
n = 1<<64 - 1
|
||||
err = strconv.ErrRange
|
||||
goto Error
|
||||
}
|
||||
n = n1
|
||||
}
|
||||
|
||||
return n, nil
|
||||
|
||||
Error:
|
||||
return n, &strconv.NumError{Func: "ParseUint", Num: string(s0), Err: err}
|
||||
}
|
||||
|
||||
// Return the first number n such that n*base >= 1<<64.
|
||||
func cutoff64(base int) uint64 {
|
||||
if base < 2 {
|
||||
return 0
|
||||
}
|
||||
return (1<<64-1)/uint64(base) + 1
|
||||
}
|
||||
Reference in New Issue
Block a user