Add mode that prints multiple worker status in console

hostPool/hostPool.go

@@ -0,0 +1,32 @@
+package gemini
+
+import (
+	"sync"
+)
+
+var ipPool = IpAddressPool{IPs: make(map[string]int)}         //nolint:gochecknoglobals
+var hostPool = HostPool{hostnames: make(map[string]struct{})} //nolint:gochecknoglobals
+
+type HostPool struct {
+	hostnames map[string]struct{}
+	Lock      sync.RWMutex
+}
+
+func (p *HostPool) Add(key string) {
+	p.Lock.Lock()
+	defer p.Lock.Unlock()
+	p.hostnames[key] = struct{}{}
+}
+
+func (p *HostPool) Get(key string) bool {
+	p.Lock.RLock()
+	defer p.Lock.RUnlock()
+	_, ok := p.hostnames[key]
+	return ok
+}
+
+func (p *HostPool) Delete(key string) {
+	p.Lock.Lock()
+	defer p.Lock.Unlock()
+	delete(p.hostnames, key)
+}