142 lines
3.2 KiB
Go
142 lines
3.2 KiB
Go
package multiaddr
|
|
|
|
import (
|
|
"bytes"
|
|
"fmt"
|
|
"log"
|
|
"strings"
|
|
)
|
|
|
|
// multiaddr is the data structure representing a Multiaddr
|
|
type multiaddr struct {
|
|
bytes []byte
|
|
}
|
|
|
|
// NewMultiaddr parses and validates an input string, returning a *Multiaddr
|
|
func NewMultiaddr(s string) (a Multiaddr, err error) {
|
|
defer func() {
|
|
if e := recover(); e != nil {
|
|
log.Printf("Panic in NewMultiaddr on input %q: %s", s, e)
|
|
err = fmt.Errorf("%v", e)
|
|
}
|
|
}()
|
|
b, err := stringToBytes(s)
|
|
if err != nil {
|
|
return nil, err
|
|
}
|
|
return multiaddr{bytes: b}, nil
|
|
}
|
|
|
|
// NewMultiaddrBytes initializes a Multiaddr from a byte representation.
|
|
// It validates it as an input string.
|
|
func NewMultiaddrBytes(b []byte) (a Multiaddr, err error) {
|
|
defer func() {
|
|
if e := recover(); e != nil {
|
|
log.Printf("Panic in NewMultiaddrBytes on input %q: %s", b, e)
|
|
err = fmt.Errorf("%v", e)
|
|
}
|
|
}()
|
|
|
|
if err := validateBytes(b); err != nil {
|
|
return nil, err
|
|
}
|
|
|
|
return multiaddr{bytes: b}, nil
|
|
}
|
|
|
|
// Equal tests whether two multiaddrs are equal
|
|
func (m multiaddr) Equal(m2 Multiaddr) bool {
|
|
return bytes.Equal(m.bytes, m2.Bytes())
|
|
}
|
|
|
|
// Bytes returns the []byte representation of this Multiaddr
|
|
//
|
|
// Do not modify the returned buffer, it may be shared.
|
|
func (m multiaddr) Bytes() []byte {
|
|
return m.bytes
|
|
}
|
|
|
|
// String returns the string representation of a Multiaddr
|
|
func (m multiaddr) String() string {
|
|
s, err := bytesToString(m.bytes)
|
|
if err != nil {
|
|
panic(fmt.Errorf("multiaddr failed to convert back to string. corrupted? %s", err))
|
|
}
|
|
return s
|
|
}
|
|
|
|
// Protocols returns the list of protocols this Multiaddr has.
|
|
// will panic in case we access bytes incorrectly.
|
|
func (m multiaddr) Protocols() []Protocol {
|
|
ps := make([]Protocol, 0, 8)
|
|
b := m.bytes
|
|
for len(b) > 0 {
|
|
code, n, err := ReadVarintCode(b)
|
|
if err != nil {
|
|
panic(err)
|
|
}
|
|
|
|
p := ProtocolWithCode(code)
|
|
if p.Code == 0 {
|
|
// this is a panic (and not returning err) because this should've been
|
|
// caught on constructing the Multiaddr
|
|
panic(fmt.Errorf("no protocol with code %d", b[0]))
|
|
}
|
|
ps = append(ps, p)
|
|
b = b[n:]
|
|
|
|
n, size, err := sizeForAddr(p, b)
|
|
if err != nil {
|
|
panic(err)
|
|
}
|
|
|
|
b = b[n+size:]
|
|
}
|
|
return ps
|
|
}
|
|
|
|
// Encapsulate wraps a given Multiaddr, returning the resulting joined Multiaddr
|
|
func (m multiaddr) Encapsulate(o Multiaddr) Multiaddr {
|
|
mb := m.bytes
|
|
ob := o.Bytes()
|
|
|
|
b := make([]byte, len(mb)+len(ob))
|
|
copy(b, mb)
|
|
copy(b[len(mb):], ob)
|
|
return multiaddr{bytes: b}
|
|
}
|
|
|
|
// Decapsulate unwraps Multiaddr up until the given Multiaddr is found.
|
|
func (m multiaddr) Decapsulate(o Multiaddr) Multiaddr {
|
|
s1 := m.String()
|
|
s2 := o.String()
|
|
i := strings.LastIndex(s1, s2)
|
|
if i < 0 {
|
|
// if multiaddr not contained, returns a copy.
|
|
cpy := make([]byte, len(m.bytes))
|
|
copy(cpy, m.bytes)
|
|
return multiaddr{bytes: cpy}
|
|
}
|
|
|
|
ma, err := NewMultiaddr(s1[:i])
|
|
if err != nil {
|
|
panic("Multiaddr.Decapsulate incorrect byte boundaries.")
|
|
}
|
|
return ma
|
|
}
|
|
|
|
var ErrProtocolNotFound = fmt.Errorf("protocol not found in multiaddr")
|
|
|
|
func (m multiaddr) ValueForProtocol(code int) (value string, err error) {
|
|
err = ErrProtocolNotFound
|
|
ForEach(m, func(c Component) bool {
|
|
if c.Protocol().Code == code {
|
|
value = c.Value()
|
|
err = nil
|
|
return false
|
|
}
|
|
return true
|
|
})
|
|
return
|
|
}
|