mirror of
https://github.com/cheat/cheat.git
synced 2024-11-23 06:21:35 +01:00
80c91cbdee
Integrate `go-git` into the application, and use it to `git clone` cheatsheets when the installer runs. Previously, the installer required that `git` be installed on the system `PATH`, so this change has to big advantages: 1. It removes that system dependency on `git` 2. It paves the way for implementing the `--update` command Additionally, `cheat` now performs a `--depth=1` clone when installing cheatsheets, which should at least somewhat improve installation times (especially on slow network connections).
89 lines
2.0 KiB
Go
89 lines
2.0 KiB
Go
// Copyright 2017 The Go Authors. All rights reserved.
|
|
// Use of this source code is governed by a BSD-style
|
|
// license that can be found in the LICENSE file.
|
|
|
|
package encoding
|
|
|
|
import (
|
|
"io"
|
|
|
|
"github.com/ProtonMail/go-crypto/openpgp/errors"
|
|
)
|
|
|
|
// OID is used to store a variable-length field with a one-octet size
|
|
// prefix. See https://tools.ietf.org/html/rfc6637#section-9.
|
|
type OID struct {
|
|
bytes []byte
|
|
}
|
|
|
|
const (
|
|
// maxOID is the maximum number of bytes in a OID.
|
|
maxOID = 254
|
|
// reservedOIDLength1 and reservedOIDLength2 are OID lengths that the RFC
|
|
// specifies are reserved.
|
|
reservedOIDLength1 = 0
|
|
reservedOIDLength2 = 0xff
|
|
)
|
|
|
|
// NewOID returns a OID initialized with bytes.
|
|
func NewOID(bytes []byte) *OID {
|
|
switch len(bytes) {
|
|
case reservedOIDLength1, reservedOIDLength2:
|
|
panic("encoding: NewOID argument length is reserved")
|
|
default:
|
|
if len(bytes) > maxOID {
|
|
panic("encoding: NewOID argument too large")
|
|
}
|
|
}
|
|
|
|
return &OID{
|
|
bytes: bytes,
|
|
}
|
|
}
|
|
|
|
// Bytes returns the decoded data.
|
|
func (o *OID) Bytes() []byte {
|
|
return o.bytes
|
|
}
|
|
|
|
// BitLength is the size in bits of the decoded data.
|
|
func (o *OID) BitLength() uint16 {
|
|
return uint16(len(o.bytes) * 8)
|
|
}
|
|
|
|
// EncodedBytes returns the encoded data.
|
|
func (o *OID) EncodedBytes() []byte {
|
|
return append([]byte{byte(len(o.bytes))}, o.bytes...)
|
|
}
|
|
|
|
// EncodedLength is the size in bytes of the encoded data.
|
|
func (o *OID) EncodedLength() uint16 {
|
|
return uint16(1 + len(o.bytes))
|
|
}
|
|
|
|
// ReadFrom reads into b the next OID from r.
|
|
func (o *OID) ReadFrom(r io.Reader) (int64, error) {
|
|
var buf [1]byte
|
|
n, err := io.ReadFull(r, buf[:])
|
|
if err != nil {
|
|
if err == io.EOF {
|
|
err = io.ErrUnexpectedEOF
|
|
}
|
|
return int64(n), err
|
|
}
|
|
|
|
switch buf[0] {
|
|
case reservedOIDLength1, reservedOIDLength2:
|
|
return int64(n), errors.UnsupportedError("reserved for future extensions")
|
|
}
|
|
|
|
o.bytes = make([]byte, buf[0])
|
|
|
|
nn, err := io.ReadFull(r, o.bytes)
|
|
if err == io.EOF {
|
|
err = io.ErrUnexpectedEOF
|
|
}
|
|
|
|
return int64(n) + int64(nn), err
|
|
}
|