chore: release v0.26.0

internal/integrations/udp/wsjthalt.go

@@ -0,0 +1,73 @@
+package udp
+
+import (
+	"bytes"
+	"encoding/binary"
+	"fmt"
+	"strings"
+
+	"hamlog/internal/applog"
+)
+
+// WSJT-X Halt Tx (message type 8) — "stop transmitting".
+//
+// The same two things the Halt Tx button and the Enable Tx toggle do in the
+// application's own window:
+//
+//	Halt Tx  type 8
+//	  id            utf8  the target application's own id
+//	  auto_tx_only  bool  false = stop the transmission NOW
+//	                      true  = let this over finish, then stop auto-Tx
+//
+// Both are useful and they are not the same operation. Stopping mid-over is what
+// you want when you have called the wrong station or realised the frequency is
+// occupied; finishing the over first is what you want when the QSO is complete
+// and cutting the transmission would leave the other end waiting for a report
+// that never lands.
+const wsjtMsgHaltTx = 8
+
+// EncodeHaltTx builds the datagram. autoTxOnly false halts immediately.
+func EncodeHaltTx(programID string, autoTxOnly bool) []byte {
+	var b bytes.Buffer
+	_ = binary.Write(&b, binary.BigEndian, uint32(wsjtMagic))
+	_ = binary.Write(&b, binary.BigEndian, uint32(2)) // schema 2 — what every current sender speaks
+	_ = binary.Write(&b, binary.BigEndian, uint32(wsjtMsgHaltTx))
+	writeQString(&b, programID)
+	var auto uint8
+	if autoTxOnly {
+		auto = 1
+	}
+	_ = binary.Write(&b, binary.BigEndian, auto)
+	return b.Bytes()
+}
+
+// SendHaltTx tells one decoding application to stop transmitting.
+//
+// Routed by PROGRAM ID and answered back to the address that instance's packets
+// arrive from, exactly like SendReply: two receivers can share one multicast
+// group, and halting the 20 m instance because the 6 m one is transmitting would
+// be worse than doing nothing.
+func (m *Manager) SendHaltTx(programID string, autoTxOnly bool) error {
+	if strings.TrimSpace(programID) == "" {
+		return fmt.Errorf("no application id — cannot tell which receiver to halt")
+	}
+	m.mu.Lock()
+	servers := make([]*Server, 0, len(m.inbound))
+	for _, s := range m.inbound {
+		servers = append(servers, s)
+	}
+	m.mu.Unlock()
+
+	for _, s := range servers {
+		conn, addr := s.replyTarget(programID)
+		if conn == nil || addr == nil {
+			continue
+		}
+		if _, err := conn.WriteToUDP(EncodeHaltTx(programID, autoTxOnly), addr); err != nil {
+			return fmt.Errorf("send halt to %s at %s: %w", programID, addr, err)
+		}
+		applog.Printf("udp: halt tx sent to %s at %s (auto_tx_only=%v)", programID, addr, autoTxOnly)
+		return nil
+	}
+	return fmt.Errorf("no packet has arrived from %q yet — nothing to halt", programID)
+}