add icu version mapper

Author: Pavel Safonov

format/postgres/common/common.go

@@ -1,6 +1,9 @@
 package common
 
-import "github.com/wader/fq/pkg/scalar"
+import (
+	"fmt"
+	"github.com/wader/fq/pkg/scalar"
+)
 
 //typedef enum DBState
 //{
@@ -33,3 +36,17 @@ var WalLevel = scalar.SToScalar{
 	1: {Sym: "WAL_LEVEL_REPLICA"},
 	2: {Sym: "WAL_LEVEL_LOGICAL"},
 }
+
+type icuVersionMapper struct{}
+
+func (m icuVersionMapper) MapScalar(s scalar.S) (scalar.S, error) {
+	a := s.ActualU()
+	major := a & 0xff
+	minor := (a >> 8) & 0xff
+	v1 := (a >> 16) & 0xff
+	v2 := (a >> 24) & 0xff
+	s.Sym = fmt.Sprintf("%d.%d.%d.%d", major, minor, v1, v2)
+	return s, nil
+}
+
+var IcuVersionMapper = icuVersionMapper{}

format/postgres/flavours/pgproee14/pg_control.go

@@ -216,7 +216,7 @@ func DecodePgControl(d *decode.D, in any) any {
 	/* XXX  4-byte padding  */
 	d.FieldU32("data_checksum_version")
 	d.FieldRawLen("mock_authentication_nonce", 32*8, scalar.RawHex)
-	d.FieldU32("icu_version")
+	d.FieldU32("icu_version", common.IcuVersionMapper)
 	d.FieldU32("pg_old_version")
 	d.FieldU32("crc")
 	d.U32()