.

t/neo/protogen.go

@@ -22,19 +22,46 @@ import (
 	"go/ast"
 	"go/parser"
 	"go/token"
+	"go/types"
+	"log"
 )
 
-var _ = ast.Print
+// information about one packet type
+type PacketType struct {
+	name    string
+	msgCode uint16 // message code for this packet type - derived from type order number in source
+}
+
+var fset = token.NewFileSet()
+var info = &types.Info{
+	Types: make(map[ast.Expr]types.TypeAndValue),
+	Uses:  make(map[*ast.Ident]types.Object),
+	Defs:  make(map[*ast.Ident]types.Object),
+}
+
+// complete position of a node
+func pos(n ast.Node) {
+	return fset.Position(n.Pos())
+}
 
 func main() {
-	fset := token.NewFileSet()
+	typeMap := map[string]*PacketType{}	// XXX needed ?
+
+	// go through proto.go and collect packets type definitions
 
 	var mode parser.Mode = 0	// parser.Trace
 	f, err := parser.ParseFile(fset, "proto.go", nil, mode)
 	if err != nil {
-		panic(err)	// XXX log
+		log.Fatal(err)	// parse error
 	}
 
+	conf := types.Config{}
+	pkg, err := conf.Check("proto", fset, []*ast.File{f}, info)
+	if err != nil {
+		log.Fatal(err)	// typecheck error
+	}
+
+
 	ncode := 0
 
 	//ast.Print(fset, f)
@@ -42,53 +69,132 @@ func main() {
 
 	for _, decl := range f.Decls {
 		// we look for types (which can be only under GenDecl)
-		gdecl, ok := decl.(*ast.GenDecl)
-		if !ok || gdecl.Tok != token.TYPE {
+		gendecl, ok := decl.(*ast.GenDecl)
+		if !ok || gendecl.Tok != token.TYPE {
 			continue
 		}
 
-		for _, spec := range gdecl.Specs {
-			tspec := spec.(*ast.TypeSpec)	// must be because tok = TYPE
-			tname := tspec.Name.Name
+		for _, spec := range gendecl.Specs {
+			typespec := spec.(*ast.TypeSpec) // must be because tok = TYPE
+			typename := typespec.Name.Name
 
-			// we are only interested in struct types
-			tstruct, ok := tspec.Type.(*ast.StructType)
-			if !ok {
+			switch t := typespec.Type.(type) {
+			default:
+				// we are only interested in struct types
 				continue
-			}
 
-			//fmt.Printf("\n%s:\n", tname)
-			//fmt.Println(tstruct)
-			//ast.Print(fset, tstruct)
+			case *ast.StructType:
+				//fmt.Printf("\n%s:\n", typename)
+				//fmt.Println(t)
+				//ast.Print(fset, t)
 
-			if ncode != 0 {
-				fmt.Println()
-			}
+				PacketType{name: typename, msgCode: ncode}
 
-			for _, fieldv := range tstruct.Fields.List {
-				// we only support simple types like uint16
-				ftype, ok := fieldv.Type.(*ast.Ident)
-				if !ok {
-					// TODO log
-					// TODO proper error message
-					panic(fmt.Sprintf("%#v not supported", fieldv.Type))
-				}
+				// if ncode != 0 {
+				// 	fmt.Println()
+				// }
 
-				if len(fieldv.Names) != 0 {
-					for _, field := range fieldv.Names {
-						fmt.Printf("%s(%d).%s\t%s\n", tname, ncode, field.Name, ftype)
+				for _, fieldv := range t.Fields.List {
+					// we only support simple types like uint16
+					ftype, ok := fieldv.Type.(*ast.Ident)
+					if !ok {
+						// TODO log
+						// TODO proper error message
+						panic(fmt.Sprintf("%#v not supported", fieldv.Type))
 					}
-				} else {
-					// no names means embedding
-					fmt.Printf("%s(%d).<%s>\n", tname, ncode, ftype)
-				}
-			}
 
-			ncode++
+					if len(fieldv.Names) != 0 {
+						for _, field := range fieldv.Names {
+							fmt.Printf("%s(%d).%s\t%s\n", typename, ncode, field.Name, ftype)
+						}
+					} else {
+						// no names means embedding
+						fmt.Printf("%s(%d).<%s>\n", typename, ncode, ftype)
+					}
+				}
 
+				ncode++
+			}
 		}
 
 		//fmt.Println(gdecl)
 		//ast.Print(fset, gdecl)
 	}
 }
+
+// wiresize returns wire size of a type
+// type must be of fixed size (e.g. not a slice or map)
+// XXX ast.Expr -> ?
+func wiresize(*ast.Expr) int {
+	// TODO
+}
+
+func gendecode(typespec *ast.TypeSpec) string {
+	buf := butes.Buffer{}
+
+	typename := typespec.Name.Name
+	t := typespec.Type.(*ast.StructType)	// must be
+	fmt.Fprintf(&buf, "func (p *%s) NEODecode(data []byte) int {\n", typename)
+
+	n := 0	// current decode pos in data
+
+	for _, fieldv := t.Fields.List {
+		// type B struct { ... }
+		//
+		// type A struct {
+		//	x, y int	<- fieldv
+		//	B		<- fieldv
+
+		// embedding: change `B` -> `B B` (field type must be Ident)
+		fieldnamev := fieldv.Names
+		if fieldnamev == nil {
+			fieldnamev = []*ast.Ident{fieldv.Type.(*ast.Ident)}
+		}
+
+		for fieldname := range fieldnamev {
+			switch fieldtype := fieldv.Type.(type) {
+			// we are processing:	<fieldname> <fieldtype>
+
+			// simple types like uint16
+			case *ast.Ident:
+				// TODO
+
+			// array or slice
+			case *ast.ArrayType:
+				if fieldtype.Len != nil {
+					log.Fatalf("%s: TODO arrays not suported", pos(fieldtype))
+				}
+
+				eltsize := wiresize(fieldtype.Elt)	// TODO
+
+				// len	  u32
+				// [len] items
+				emit("length = Uint32(data[%s:])", n)
+				n += 4
+				emit("for ; length != 0; length-- {")
+				emit("}")
+
+
+
+			// map
+			case *ast.MapType:
+				// len	  u32
+				// [len] key, value
+				emit("length = Uint32(data[%s:])", n)
+				n += 4
+
+				keysize := wiresize(fieldtype.Key)
+				valsize := wiresize(fieldtype.Value)
+
+			// XXX *ast.StructType ?
+
+			default:
+				panic()	// TODO
+			}
+		}
+	}
+
+	fmt.Fprintf(&buf, "}\n")
+	// TODO format.Source(buf.Bytes())	(XXX -> better at top-level for whole file)
+	return buf.String()
+}

t/neo/storage.go

@@ -63,7 +63,7 @@ func (stor *StorageApplication) ServeLink(ctx context.Context, link *NodeLink) {
 	switch pkt.MsgCode {
 	case GetObject:
 		req := GetObject{}
-		err = req.Decode(pkt.Payload())
+		err = req.NEODecode(pkt.Payload())
 		if err != nil {
 			sendErr("malformed GetObject packet:", err)
 		}