155 lines
3.0 KiB
Go
155 lines
3.0 KiB
Go
package multiaddr
|
|
|
|
import "fmt"
|
|
|
|
// Split returns the sub-address portions of a multiaddr.
|
|
func Split(m Multiaddr) []Multiaddr {
|
|
var addrs []Multiaddr
|
|
ForEach(m, func(c Component) bool {
|
|
addrs = append(addrs, &c)
|
|
return true
|
|
})
|
|
return addrs
|
|
}
|
|
|
|
// Join returns a combination of addresses.
|
|
func Join(ms ...Multiaddr) Multiaddr {
|
|
switch len(ms) {
|
|
case 0:
|
|
// empty multiaddr, unfortunately, we have callers that rely on
|
|
// this contract.
|
|
return multiaddr{}
|
|
case 1:
|
|
return ms[0]
|
|
}
|
|
|
|
length := 0
|
|
bs := make([][]byte, len(ms))
|
|
for i, m := range ms {
|
|
bs[i] = m.Bytes()
|
|
length += len(bs[i])
|
|
}
|
|
|
|
bidx := 0
|
|
b := make([]byte, length)
|
|
for _, mb := range bs {
|
|
bidx += copy(b[bidx:], mb)
|
|
}
|
|
return multiaddr{bytes: b}
|
|
}
|
|
|
|
// Cast re-casts a byte slice as a multiaddr. will panic if it fails to parse.
|
|
func Cast(b []byte) Multiaddr {
|
|
m, err := NewMultiaddrBytes(b)
|
|
if err != nil {
|
|
panic(fmt.Errorf("multiaddr failed to parse: %s", err))
|
|
}
|
|
return m
|
|
}
|
|
|
|
// StringCast like Cast, but parses a string. Will also panic if it fails to parse.
|
|
func StringCast(s string) Multiaddr {
|
|
m, err := NewMultiaddr(s)
|
|
if err != nil {
|
|
panic(fmt.Errorf("multiaddr failed to parse: %s", err))
|
|
}
|
|
return m
|
|
}
|
|
|
|
// SplitFirst returns the first component and the rest of the multiaddr.
|
|
func SplitFirst(m Multiaddr) (*Component, Multiaddr) {
|
|
b := m.Bytes()
|
|
if len(b) == 0 {
|
|
return nil, nil
|
|
}
|
|
n, c, err := readComponent(b)
|
|
if err != nil {
|
|
panic(err)
|
|
}
|
|
if len(b) == n {
|
|
return &c, nil
|
|
}
|
|
return &c, multiaddr{b[n:]}
|
|
}
|
|
|
|
// SplitLast returns the rest of the multiaddr and the last component.
|
|
func SplitLast(m Multiaddr) (Multiaddr, *Component) {
|
|
b := m.Bytes()
|
|
if len(b) == 0 {
|
|
return nil, nil
|
|
}
|
|
|
|
var (
|
|
c Component
|
|
err error
|
|
offset int
|
|
)
|
|
for {
|
|
var n int
|
|
n, c, err = readComponent(b[offset:])
|
|
if err != nil {
|
|
panic(err)
|
|
}
|
|
if len(b) == n+offset {
|
|
// Reached end
|
|
if offset == 0 {
|
|
// Only one component
|
|
return nil, &c
|
|
}
|
|
return multiaddr{b[:offset]}, &c
|
|
}
|
|
offset += n
|
|
}
|
|
}
|
|
|
|
// SplitFunc splits the multiaddr when the callback first returns true. The
|
|
// component on which the callback first returns will be included in the
|
|
// *second* multiaddr.
|
|
func SplitFunc(m Multiaddr, cb func(Component) bool) (Multiaddr, Multiaddr) {
|
|
b := m.Bytes()
|
|
if len(b) == 0 {
|
|
return nil, nil
|
|
}
|
|
var (
|
|
c Component
|
|
err error
|
|
offset int
|
|
)
|
|
for offset < len(b) {
|
|
var n int
|
|
n, c, err = readComponent(b[offset:])
|
|
if err != nil {
|
|
panic(err)
|
|
}
|
|
if cb(c) {
|
|
break
|
|
}
|
|
offset += n
|
|
}
|
|
switch offset {
|
|
case 0:
|
|
return nil, m
|
|
case len(b):
|
|
return m, nil
|
|
default:
|
|
return multiaddr{b[:offset]}, multiaddr{b[offset:]}
|
|
}
|
|
}
|
|
|
|
// ForEach walks over the multiaddr, component by component.
|
|
//
|
|
// This function iterates over components *by value* to avoid allocating.
|
|
func ForEach(m Multiaddr, cb func(c Component) bool) {
|
|
b := m.Bytes()
|
|
for len(b) > 0 {
|
|
n, c, err := readComponent(b)
|
|
if err != nil {
|
|
panic(err)
|
|
}
|
|
if !cb(c) {
|
|
return
|
|
}
|
|
b = b[n:]
|
|
}
|
|
}
|