-
Notifications
You must be signed in to change notification settings - Fork 111
Commit
This commit does not belong to any branch on this repository, and may belong to a fork outside of the repository.
Merge pull request #81 from multiformats/feat/component
add component/foreach helpers
- Loading branch information
Showing
7 changed files
with
389 additions
and
57 deletions.
There are no files selected for viewing
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
Original file line number | Diff line number | Diff line change |
---|---|---|
@@ -0,0 +1,132 @@ | ||
package multiaddr | ||
|
||
import ( | ||
"bytes" | ||
"encoding/binary" | ||
"fmt" | ||
"strings" | ||
) | ||
|
||
// Component is a single multiaddr Component. | ||
type Component struct { | ||
bytes []byte | ||
protocol Protocol | ||
offset int | ||
} | ||
|
||
func (c *Component) Bytes() []byte { | ||
return c.bytes | ||
} | ||
|
||
func (c *Component) Equal(o Multiaddr) bool { | ||
return bytes.Equal(c.bytes, o.Bytes()) | ||
} | ||
|
||
func (c *Component) Protocols() []Protocol { | ||
return []Protocol{c.protocol} | ||
} | ||
|
||
func (c *Component) Decapsulate(o Multiaddr) Multiaddr { | ||
if c.Equal(o) { | ||
return nil | ||
} | ||
return c | ||
} | ||
|
||
func (c *Component) Encapsulate(o Multiaddr) Multiaddr { | ||
m := multiaddr{bytes: c.bytes} | ||
return m.Encapsulate(o) | ||
} | ||
|
||
func (c *Component) ValueForProtocol(code int) (string, error) { | ||
if c.protocol.Code != code { | ||
return "", ErrProtocolNotFound | ||
} | ||
return c.Value(), nil | ||
} | ||
|
||
func (c *Component) Protocol() Protocol { | ||
return c.protocol | ||
} | ||
|
||
func (c *Component) RawValue() []byte { | ||
return c.bytes[c.offset:] | ||
} | ||
|
||
func (c *Component) Value() string { | ||
if c.protocol.Transcoder == nil { | ||
return "" | ||
} | ||
value, err := c.protocol.Transcoder.BytesToString(c.bytes[c.offset:]) | ||
if err != nil { | ||
// This Component must have been checked. | ||
panic(err) | ||
} | ||
return value | ||
} | ||
|
||
func (c *Component) String() string { | ||
var b strings.Builder | ||
c.writeTo(&b) | ||
return b.String() | ||
} | ||
|
||
// writeTo is an efficient, private function for string-formatting a multiaddr. | ||
// Trust me, we tend to allocate a lot when doing this. | ||
func (c *Component) writeTo(b *strings.Builder) { | ||
b.WriteByte('/') | ||
b.WriteString(c.protocol.Name) | ||
value := c.Value() | ||
if len(value) == 0 { | ||
return | ||
} | ||
if !(c.protocol.Path && value[0] == '/') { | ||
b.WriteByte('/') | ||
} | ||
b.WriteString(value) | ||
} | ||
|
||
// NewComponent constructs a new multiaddr component | ||
func NewComponent(protocol, value string) (*Component, error) { | ||
p := ProtocolWithName(protocol) | ||
if p.Code == 0 { | ||
return nil, fmt.Errorf("unsupported protocol: %s", protocol) | ||
} | ||
if p.Transcoder != nil { | ||
bts, err := p.Transcoder.StringToBytes(value) | ||
if err != nil { | ||
return nil, err | ||
} | ||
return newComponent(p, bts), nil | ||
} else if value != "" { | ||
return nil, fmt.Errorf("protocol %s doesn't take a value", p.Name) | ||
} | ||
return newComponent(p, nil), nil | ||
// TODO: handle path /? | ||
} | ||
|
||
func newComponent(protocol Protocol, bvalue []byte) *Component { | ||
size := len(bvalue) | ||
size += len(protocol.VCode) | ||
if protocol.Size < 0 { | ||
size += VarintSize(len(bvalue)) | ||
} | ||
maddr := make([]byte, size) | ||
var offset int | ||
offset += copy(maddr[offset:], protocol.VCode) | ||
if protocol.Size < 0 { | ||
offset += binary.PutUvarint(maddr[offset:], uint64(len(bvalue))) | ||
} | ||
copy(maddr[offset:], bvalue) | ||
|
||
// For debugging | ||
if len(maddr) != offset+len(bvalue) { | ||
panic("incorrect length") | ||
} | ||
|
||
return &Component{ | ||
bytes: maddr, | ||
protocol: protocol, | ||
offset: offset, | ||
} | ||
} |
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
Oops, something went wrong.