Initial go port of epics

pkg/ca/search_test.go

@@ -0,0 +1,137 @@
+package ca
+
+import (
+	"net"
+	"testing"
+
+	"github.com/uopi/goca/proto"
+)
+
+// buildOldSearchReply builds a CA_PROTO_SEARCH UDP reply using the old
+// payload format (CA < 4.9): [minor_version(2)][pad(2)][IP(4)].
+// When ip is nil, the IP field is 0xFFFFFFFF (use-sender convention).
+func buildOldSearchReply(searchID uint32, serverIP net.IP, port int) []byte {
+	payload := make([]byte, 8)
+	payload[0] = 0x00
+	payload[1] = proto.MinorVersion // e.g. 0x0D = 13
+	// payload[2:4] = 0x00 0x00 (pad)
+	if serverIP == nil {
+		payload[4] = 0xFF
+		payload[5] = 0xFF
+		payload[6] = 0xFF
+		payload[7] = 0xFF
+	} else {
+		copy(payload[4:], serverIP.To4())
+	}
+	h := proto.Header{
+		Command:    proto.CmdSearch,
+		DataType:   uint16(port),
+		Parameter1: proto.MinorVersion,
+		Parameter2: searchID,
+	}
+	return proto.BuildMessage(h, payload)
+}
+
+// TestParseReplyOldFormatAllFF verifies the old format with 0xFFFFFFFF IP.
+func TestParseReplyOldFormatAllFF(t *testing.T) {
+	se := &searchEngine{waiters: make(map[uint32]*searchWaiter)}
+	const searchID = uint32(42)
+	result := make(chan searchResult, 1)
+	se.mu.Lock()
+	se.waiters[searchID] = &searchWaiter{pvName: "TEST:PV", ch: result}
+	se.mu.Unlock()
+
+	pkt := buildOldSearchReply(searchID, nil, 5064) // nil → 0xFFFFFFFF
+	src := &net.UDPAddr{IP: net.ParseIP("127.0.0.1"), Port: 5064}
+	se.parseReply(pkt, src)
+
+	select {
+	case r := <-result:
+		if r.addr != "127.0.0.1:5064" {
+			t.Errorf("addr = %q, want 127.0.0.1:5064", r.addr)
+		}
+	default:
+		t.Fatal("parseReply did not deliver a result")
+	}
+}
+
+// TestParseReplyOldFormatAllZero verifies the old format with 0.0.0.0 IP
+// (used by some EPICS Base versions to also mean "use sender IP").
+func TestParseReplyOldFormatAllZero(t *testing.T) {
+	se := &searchEngine{waiters: make(map[uint32]*searchWaiter)}
+	const searchID = uint32(43)
+	result := make(chan searchResult, 1)
+	se.mu.Lock()
+	se.waiters[searchID] = &searchWaiter{pvName: "TEST:PV", ch: result}
+	se.mu.Unlock()
+
+	pkt := buildOldSearchReply(searchID, net.IPv4(0, 0, 0, 0).To4(), 5064)
+	src := &net.UDPAddr{IP: net.ParseIP("127.0.0.1"), Port: 5064}
+	se.parseReply(pkt, src)
+
+	select {
+	case r := <-result:
+		if r.addr != "127.0.0.1:5064" {
+			t.Errorf("addr = %q, want 127.0.0.1:5064", r.addr)
+		}
+	default:
+		t.Fatal("parseReply did not deliver a result")
+	}
+}
+
+// TestParseReplyOldFormatExplicitIP verifies that an explicit server IP in
+// the old payload format is read from the correct offset (bytes [4:8]).
+func TestParseReplyOldFormatExplicitIP(t *testing.T) {
+	se := &searchEngine{
+		waiters: make(map[uint32]*searchWaiter),
+	}
+
+	const searchID = uint32(7)
+	result := make(chan searchResult, 1)
+	se.mu.Lock()
+	se.waiters[searchID] = &searchWaiter{pvName: "TEST:PV2", ch: result}
+	se.mu.Unlock()
+
+	explicitIP := net.ParseIP("10.0.0.5").To4()
+	pkt := buildOldSearchReply(searchID, explicitIP, 5064)
+	src := &net.UDPAddr{IP: net.ParseIP("10.0.0.5"), Port: 5064}
+
+	se.parseReply(pkt, src)
+
+	select {
+	case r := <-result:
+		if r.addr != "10.0.0.5:5064" {
+			t.Errorf("addr = %q, want 10.0.0.5:5064", r.addr)
+		}
+	default:
+		t.Fatal("parseReply did not deliver a result")
+	}
+}
+
+// TestParseReplyNewFormat verifies the new payload format (IP at [0:4]).
+func TestParseReplyNewFormat(t *testing.T) {
+	se := &searchEngine{
+		waiters: make(map[uint32]*searchWaiter),
+	}
+
+	const searchID = uint32(99)
+	result := make(chan searchResult, 1)
+	se.mu.Lock()
+	se.waiters[searchID] = &searchWaiter{pvName: "TEST:PV3", ch: result}
+	se.mu.Unlock()
+
+	// New format: IP = 0xFFFFFFFF at [0:4].
+	pkt := EncodeSearchReply(searchID, nil, 5064)
+	src := &net.UDPAddr{IP: net.ParseIP("192.168.1.10"), Port: 5064}
+
+	se.parseReply(pkt, src)
+
+	select {
+	case r := <-result:
+		if r.addr != "192.168.1.10:5064" {
+			t.Errorf("addr = %q, want 192.168.1.10:5064", r.addr)
+		}
+	default:
+		t.Fatal("parseReply did not deliver a result")
+	}
+}