cloudflared-mirror/edgediscovery/allregions/region.go

79 lines
1.9 KiB
Go

package allregions
import (
"net"
)
// Region contains cloudflared edge addresses. The edge is partitioned into several regions for
// redundancy purposes.
type Region struct {
connFor map[*net.TCPAddr]UsedBy
}
// NewRegion creates a region with the given addresses, which are all unused.
func NewRegion(addrs []*net.TCPAddr) Region {
// The zero value of UsedBy is Unused(), so we can just initialize the map's values with their
// zero values.
m := make(map[*net.TCPAddr]UsedBy)
for _, addr := range addrs {
m[addr] = Unused()
}
return Region{connFor: m}
}
// AddrUsedBy finds the address used by the given connection in this region.
// Returns nil if the connection isn't using any IP.
func (r *Region) AddrUsedBy(connID int) *net.TCPAddr {
for addr, used := range r.connFor {
if used.Used && used.ConnID == connID {
return addr
}
}
return nil
}
// AvailableAddrs counts how many unused addresses this region contains.
func (r Region) AvailableAddrs() int {
n := 0
for _, usedby := range r.connFor {
if !usedby.Used {
n++
}
}
return n
}
// GetUnusedIP returns a random unused address in this region.
// Returns nil if all addresses are in use.
func (r Region) GetUnusedIP(excluding *net.TCPAddr) *net.TCPAddr {
for addr, usedby := range r.connFor {
if !usedby.Used && addr != excluding {
return addr
}
}
return nil
}
// Use the address, assigning it to a proxy connection.
func (r Region) Use(addr *net.TCPAddr, connID int) {
r.connFor[addr] = InUse(connID)
}
// GetAnyAddress returns an arbitrary address from the region.
func (r Region) GetAnyAddress() *net.TCPAddr {
for addr := range r.connFor {
return addr
}
return nil
}
// GiveBack the address, ensuring it is no longer assigned to an IP.
// Returns true if the address is in this region.
func (r Region) GiveBack(addr *net.TCPAddr) (ok bool) {
if _, ok := r.connFor[addr]; !ok {
return false
}
r.connFor[addr] = Unused()
return true
}