Exemple #1
0
func (p *parser) parseSignature(n *parse.Node, scope *ast.Scope) *ast.FuncType {
	funcType := ast.FuncType{
		Params: p.parseParams(n.Child(0), scope),
	}
	if n.ChildCount() > 1 {
		funcType.Results = p.parseResults(n.Child(1), scope)
	}
	return &funcType
}
Exemple #2
0
func (p *Package) writeDefsFunc(fc, fgo2 *os.File, n *Name) {
	name := n.Go
	gtype := n.FuncType.Go
	if n.AddError {
		// Add "os.Error" to return type list.
		// Type list is known to be 0 or 1 element - it's a C function.
		err := &ast.Field{Type: ast.NewIdent("os.Error")}
		l := gtype.Results.List
		if len(l) == 0 {
			l = []*ast.Field{err}
		} else {
			l = []*ast.Field{l[0], err}
		}
		t := new(ast.FuncType)
		*t = *gtype
		t.Results = &ast.FieldList{List: l}
		gtype = t
	}

	// Go func declaration.
	d := &ast.FuncDecl{
		Name: ast.NewIdent(n.Mangle),
		Type: gtype,
	}
	printer.Fprint(fgo2, fset, d)
	fmt.Fprintf(fgo2, "\n")

	if name == "CString" || name == "GoString" || name == "GoStringN" {
		// The builtins are already defined in the C prolog.
		return
	}

	var argSize int64
	_, argSize = p.structType(n)

	// C wrapper calls into gcc, passing a pointer to the argument frame.
	fmt.Fprintf(fc, "void _cgo%s%s(void*);\n", cPrefix, n.Mangle)
	fmt.Fprintf(fc, "\n")
	fmt.Fprintf(fc, "void\n")
	if argSize == 0 {
		argSize++
	}
	fmt.Fprintf(fc, "·%s(struct{uint8 x[%d];}p)\n", n.Mangle, argSize)
	fmt.Fprintf(fc, "{\n")
	fmt.Fprintf(fc, "\truntime·cgocall(_cgo%s%s, &p);\n", cPrefix, n.Mangle)
	if n.AddError {
		// gcc leaves errno in first word of interface at end of p.
		// check whether it is zero; if so, turn interface into nil.
		// if not, turn interface into errno.
		// Go init function initializes ·_Cerrno with an os.Errno
		// for us to copy.
		fmt.Fprintln(fc, `	{
			int32 e;
			void **v;
			v = (void**)(&p+1) - 2;	/* v = final two void* of p */
			e = *(int32*)v;
			v[0] = (void*)0xdeadbeef;
			v[1] = (void*)0xdeadbeef;
			if(e == 0) {
				/* nil interface */
				v[0] = 0;
				v[1] = 0;
			} else {
				·_Cerrno(v, e);	/* fill in v as os.Error for errno e */
			}
		}`)
	}
	fmt.Fprintf(fc, "}\n")
	fmt.Fprintf(fc, "\n")
}
Exemple #3
0
func (p *Package) writeDefsFunc(fgo2 io.Writer, n *Name, callsMalloc *bool) {
	name := n.Go
	gtype := n.FuncType.Go
	void := gtype.Results == nil || len(gtype.Results.List) == 0
	if n.AddError {
		// Add "error" to return type list.
		// Type list is known to be 0 or 1 element - it's a C function.
		err := &ast.Field{Type: ast.NewIdent("error")}
		l := gtype.Results.List
		if len(l) == 0 {
			l = []*ast.Field{err}
		} else {
			l = []*ast.Field{l[0], err}
		}
		t := new(ast.FuncType)
		*t = *gtype
		t.Results = &ast.FieldList{List: l}
		gtype = t
	}

	// Go func declaration.
	d := &ast.FuncDecl{
		Name: ast.NewIdent(n.Mangle),
		Type: gtype,
	}

	// Builtins defined in the C prolog.
	inProlog := builtinDefs[name] != ""
	cname := fmt.Sprintf("_cgo%s%s", cPrefix, n.Mangle)
	paramnames := []string(nil)
	for i, param := range d.Type.Params.List {
		paramName := fmt.Sprintf("p%d", i)
		param.Names = []*ast.Ident{ast.NewIdent(paramName)}
		paramnames = append(paramnames, paramName)
	}

	if *gccgo {
		// Gccgo style hooks.
		fmt.Fprint(fgo2, "\n")
		conf.Fprint(fgo2, fset, d)
		fmt.Fprint(fgo2, " {\n")
		if !inProlog {
			fmt.Fprint(fgo2, "\tdefer syscall.CgocallDone()\n")
			fmt.Fprint(fgo2, "\tsyscall.Cgocall()\n")
		}
		if n.AddError {
			fmt.Fprint(fgo2, "\tsyscall.SetErrno(0)\n")
		}
		fmt.Fprint(fgo2, "\t")
		if !void {
			fmt.Fprint(fgo2, "r := ")
		}
		fmt.Fprintf(fgo2, "%s(%s)\n", cname, strings.Join(paramnames, ", "))

		if n.AddError {
			fmt.Fprint(fgo2, "\te := syscall.GetErrno()\n")
			fmt.Fprint(fgo2, "\tif e != 0 {\n")
			fmt.Fprint(fgo2, "\t\treturn ")
			if !void {
				fmt.Fprint(fgo2, "r, ")
			}
			fmt.Fprint(fgo2, "e\n")
			fmt.Fprint(fgo2, "\t}\n")
			fmt.Fprint(fgo2, "\treturn ")
			if !void {
				fmt.Fprint(fgo2, "r, ")
			}
			fmt.Fprint(fgo2, "nil\n")
		} else if !void {
			fmt.Fprint(fgo2, "\treturn r\n")
		}

		fmt.Fprint(fgo2, "}\n")

		// declare the C function.
		fmt.Fprintf(fgo2, "//extern %s\n", cname)
		d.Name = ast.NewIdent(cname)
		if n.AddError {
			l := d.Type.Results.List
			d.Type.Results.List = l[:len(l)-1]
		}
		conf.Fprint(fgo2, fset, d)
		fmt.Fprint(fgo2, "\n")

		return
	}

	if inProlog {
		fmt.Fprint(fgo2, builtinDefs[name])
		if strings.Contains(builtinDefs[name], "_cgo_cmalloc") {
			*callsMalloc = true
		}
		return
	}

	// Wrapper calls into gcc, passing a pointer to the argument frame.
	fmt.Fprintf(fgo2, "//go:cgo_import_static %s\n", cname)
	fmt.Fprintf(fgo2, "//go:linkname __cgofn_%s %s\n", cname, cname)
	fmt.Fprintf(fgo2, "var __cgofn_%s byte\n", cname)
	fmt.Fprintf(fgo2, "var %s = unsafe.Pointer(&__cgofn_%s)\n", cname, cname)

	nret := 0
	if !void {
		d.Type.Results.List[0].Names = []*ast.Ident{ast.NewIdent("r1")}
		nret = 1
	}
	if n.AddError {
		d.Type.Results.List[nret].Names = []*ast.Ident{ast.NewIdent("r2")}
	}

	fmt.Fprint(fgo2, "\n")
	fmt.Fprint(fgo2, "//go:cgo_unsafe_args\n")
	conf.Fprint(fgo2, fset, d)
	fmt.Fprint(fgo2, " {\n")

	// NOTE: Using uintptr to hide from escape analysis.
	arg := "0"
	if len(paramnames) > 0 {
		arg = "uintptr(unsafe.Pointer(&p0))"
	} else if !void {
		arg = "uintptr(unsafe.Pointer(&r1))"
	}

	prefix := ""
	if n.AddError {
		prefix = "errno := "
	}
	fmt.Fprintf(fgo2, "\t%s_cgo_runtime_cgocall(%s, %s)\n", prefix, cname, arg)
	if n.AddError {
		fmt.Fprintf(fgo2, "\tif errno != 0 { r2 = syscall.Errno(errno) }\n")
	}
	fmt.Fprintf(fgo2, "\tif _Cgo_always_false {\n")
	for i := range d.Type.Params.List {
		fmt.Fprintf(fgo2, "\t\t_Cgo_use(p%d)\n", i)
	}
	fmt.Fprintf(fgo2, "\t}\n")
	fmt.Fprintf(fgo2, "\treturn\n")
	fmt.Fprintf(fgo2, "}\n")
}
Exemple #4
0
func (p *Package) writeDefsFunc(fc, fgo2 *os.File, n *Name) {
	name := n.Go
	gtype := n.FuncType.Go
	void := gtype.Results == nil || len(gtype.Results.List) == 0
	if n.AddError {
		// Add "error" to return type list.
		// Type list is known to be 0 or 1 element - it's a C function.
		err := &ast.Field{Type: ast.NewIdent("error")}
		l := gtype.Results.List
		if len(l) == 0 {
			l = []*ast.Field{err}
		} else {
			l = []*ast.Field{l[0], err}
		}
		t := new(ast.FuncType)
		*t = *gtype
		t.Results = &ast.FieldList{List: l}
		gtype = t
	}

	// Go func declaration.
	d := &ast.FuncDecl{
		Name: ast.NewIdent(n.Mangle),
		Type: gtype,
	}

	// Builtins defined in the C prolog.
	inProlog := name == "CString" || name == "GoString" || name == "GoStringN" || name == "GoBytes" || name == "_CMalloc"

	if *gccgo {
		// Gccgo style hooks.
		fmt.Fprint(fgo2, "\n")
		cname := fmt.Sprintf("_cgo%s%s", cPrefix, n.Mangle)
		paramnames := []string(nil)
		for i, param := range d.Type.Params.List {
			paramName := fmt.Sprintf("p%d", i)
			param.Names = []*ast.Ident{ast.NewIdent(paramName)}
			paramnames = append(paramnames, paramName)
		}

		conf.Fprint(fgo2, fset, d)
		fmt.Fprint(fgo2, " {\n")
		if !inProlog {
			fmt.Fprint(fgo2, "\tdefer syscall.CgocallDone()\n")
			fmt.Fprint(fgo2, "\tsyscall.Cgocall()\n")
		}
		if n.AddError {
			fmt.Fprint(fgo2, "\tsyscall.SetErrno(0)\n")
		}
		fmt.Fprint(fgo2, "\t")
		if !void {
			fmt.Fprint(fgo2, "r := ")
		}
		fmt.Fprintf(fgo2, "%s(%s)\n", cname, strings.Join(paramnames, ", "))

		if n.AddError {
			fmt.Fprint(fgo2, "\te := syscall.GetErrno()\n")
			fmt.Fprint(fgo2, "\tif e != 0 {\n")
			fmt.Fprint(fgo2, "\t\treturn ")
			if !void {
				fmt.Fprint(fgo2, "r, ")
			}
			fmt.Fprint(fgo2, "e\n")
			fmt.Fprint(fgo2, "\t}\n")
			fmt.Fprint(fgo2, "\treturn ")
			if !void {
				fmt.Fprint(fgo2, "r, ")
			}
			fmt.Fprint(fgo2, "nil\n")
		} else if !void {
			fmt.Fprint(fgo2, "\treturn r\n")
		}

		fmt.Fprint(fgo2, "}\n")

		// declare the C function.
		fmt.Fprintf(fgo2, "//extern _cgo%s%s\n", cPrefix, n.Mangle)
		d.Name = ast.NewIdent(cname)
		if n.AddError {
			l := d.Type.Results.List
			d.Type.Results.List = l[:len(l)-1]
		}
		conf.Fprint(fgo2, fset, d)
		fmt.Fprint(fgo2, "\n")

		return
	}
	conf.Fprint(fgo2, fset, d)
	fmt.Fprint(fgo2, "\n")

	if inProlog {
		return
	}

	var argSize int64
	_, argSize = p.structType(n)

	// C wrapper calls into gcc, passing a pointer to the argument frame.
	fmt.Fprintf(fc, "#pragma cgo_import_static _cgo%s%s\n", cPrefix, n.Mangle)
	fmt.Fprintf(fc, "void _cgo%s%s(void*);\n", cPrefix, n.Mangle)
	fmt.Fprintf(fc, "\n")
	fmt.Fprintf(fc, "void\n")
	if argSize == 0 {
		argSize++
	}
	// TODO(rsc): The struct here should declare pointers only where
	// there are pointers in the actual argument frame.
	// This is a workaround for golang.org/issue/6397.
	fmt.Fprintf(fc, "·%s(struct{", n.Mangle)
	if n := argSize / p.PtrSize; n > 0 {
		fmt.Fprintf(fc, "void *y[%d];", n)
	}
	if n := argSize % p.PtrSize; n > 0 {
		fmt.Fprintf(fc, "uint8 x[%d];", n)
	}
	fmt.Fprintf(fc, "}p)\n")
	fmt.Fprintf(fc, "{\n")
	fmt.Fprintf(fc, "\truntime·cgocall(_cgo%s%s, &p);\n", cPrefix, n.Mangle)
	if n.AddError {
		// gcc leaves errno in first word of interface at end of p.
		// check whether it is zero; if so, turn interface into nil.
		// if not, turn interface into errno.
		// Go init function initializes ·_Cerrno with an os.Errno
		// for us to copy.
		fmt.Fprintln(fc, `	{
			int32 e;
			void **v;
			v = (void**)(&p+1) - 2;	/* v = final two void* of p */
			e = *(int32*)v;
			v[0] = (void*)0xdeadbeef;
			v[1] = (void*)0xdeadbeef;
			if(e == 0) {
				/* nil interface */
				v[0] = 0;
				v[1] = 0;
			} else {
				·_Cerrno(v, e);	/* fill in v as error for errno e */
			}
		}`)
	}
	fmt.Fprintf(fc, "}\n")
	fmt.Fprintf(fc, "\n")
}
Exemple #5
0
func (p *Package) writeDefsFunc(fc, fgo2 *os.File, n *Name) {
	name := n.Go
	gtype := n.FuncType.Go
	if n.AddError {
		// Add "error" to return type list.
		// Type list is known to be 0 or 1 element - it's a C function.
		err := &ast.Field{Type: ast.NewIdent("error")}
		l := gtype.Results.List
		if len(l) == 0 {
			l = []*ast.Field{err}
		} else {
			l = []*ast.Field{l[0], err}
		}
		t := new(ast.FuncType)
		*t = *gtype
		t.Results = &ast.FieldList{List: l}
		gtype = t
	}

	// Go func declaration.
	d := &ast.FuncDecl{
		Name: ast.NewIdent(n.Mangle),
		Type: gtype,
	}

	if *gccgo {
		// Gccgo style hooks.
		// we hook directly into C. gccgo goes not support cgocall yet.
		if !n.AddError {
			fmt.Fprintf(fgo2, "//extern %s\n", n.C)
			conf.Fprint(fgo2, fset, d)
			fmt.Fprint(fgo2, "\n")
		} else {
			// write a small wrapper to retrieve errno.
			cname := fmt.Sprintf("_cgo%s%s", cPrefix, n.Mangle)
			paramnames := []string(nil)
			for i, param := range d.Type.Params.List {
				paramName := fmt.Sprintf("p%d", i)
				param.Names = []*ast.Ident{ast.NewIdent(paramName)}
				paramnames = append(paramnames, paramName)
			}
			conf.Fprint(fgo2, fset, d)
			fmt.Fprintf(fgo2, "{\n")
			fmt.Fprintf(fgo2, "\tsyscall.SetErrno(0)\n")
			fmt.Fprintf(fgo2, "\tr := %s(%s)\n", cname, strings.Join(paramnames, ", "))
			fmt.Fprintf(fgo2, "\te := syscall.GetErrno()\n")
			fmt.Fprintf(fgo2, "\tif e != 0 {\n")
			fmt.Fprintf(fgo2, "\t\treturn r, e\n")
			fmt.Fprintf(fgo2, "\t}\n")
			fmt.Fprintf(fgo2, "\treturn r, nil\n")
			fmt.Fprintf(fgo2, "}\n")
			// declare the C function.
			fmt.Fprintf(fgo2, "//extern %s\n", n.C)
			d.Name = ast.NewIdent(cname)
			l := d.Type.Results.List
			d.Type.Results.List = l[:len(l)-1]
			conf.Fprint(fgo2, fset, d)
			fmt.Fprint(fgo2, "\n")
		}
		return
	}
	conf.Fprint(fgo2, fset, d)
	fmt.Fprint(fgo2, "\n")

	if name == "CString" || name == "GoString" || name == "GoStringN" || name == "GoBytes" {
		// The builtins are already defined in the C prolog.
		return
	}

	var argSize int64
	_, argSize = p.structType(n)

	// C wrapper calls into gcc, passing a pointer to the argument frame.
	fmt.Fprintf(fc, "void _cgo%s%s(void*);\n", cPrefix, n.Mangle)
	fmt.Fprintf(fc, "\n")
	fmt.Fprintf(fc, "void\n")
	if argSize == 0 {
		argSize++
	}
	fmt.Fprintf(fc, "·%s(struct{uint8 x[%d];}p)\n", n.Mangle, argSize)
	fmt.Fprintf(fc, "{\n")
	fmt.Fprintf(fc, "\truntime·cgocall(_cgo%s%s, &p);\n", cPrefix, n.Mangle)
	if n.AddError {
		// gcc leaves errno in first word of interface at end of p.
		// check whether it is zero; if so, turn interface into nil.
		// if not, turn interface into errno.
		// Go init function initializes ·_Cerrno with an os.Errno
		// for us to copy.
		fmt.Fprintln(fc, `	{
			int32 e;
			void **v;
			v = (void**)(&p+1) - 2;	/* v = final two void* of p */
			e = *(int32*)v;
			v[0] = (void*)0xdeadbeef;
			v[1] = (void*)0xdeadbeef;
			if(e == 0) {
				/* nil interface */
				v[0] = 0;
				v[1] = 0;
			} else {
				·_Cerrno(v, e);	/* fill in v as error for errno e */
			}
		}`)
	}
	fmt.Fprintf(fc, "}\n")
	fmt.Fprintf(fc, "\n")
}