// loadInclude tries to load the given reference as an include file.
// Parses it into the supplied AST and verifies that it contains what
// we are looking for.
func loadInclude(ast *parser.AST, includes []string, r *parser.Name) (err error) {
var file string
name := r.Data + ".dasm"
walker := func(f string, info os.FileInfo, e error) (err error) {
if info.IsDir() {
return
}
parts := strings.Split(f, string(filepath.Separator))
for i := range parts {
if len(parts[i]) == 0 {
continue
}
if parts[i][0] == '_' {
return nil
}
}
fb := parts[len(parts)-1]
if fb == name {
file, err = filepath.Abs(f)
if err != nil {
return
}
return io.EOF // Signal walker to stop.
}
return nil
}
for i := range includes {
filepath.Walk(includes[i], walker)
if len(file) > 0 {
break
}
}
if len(file) == 0 {
return parser.NewParseError(ast.Files[r.File()], r.Line(), r.Col(),
"Undefined reference: %q", r.Data)
}
if err = readSource(ast, file); err != nil {
return
}
// Test if the code actually contains the label we are looking for.
if !includeHasLabel(ast, file, r.Data) {
return parser.NewParseError(ast.Files[r.File()], r.Line(), r.Col(),
"Undefined reference: %q. Include file was found, but "+
"it did not define the desired label.", r.Data)
}
// This new file may hold its own include requirements.
return resolveIncludes(ast, includes)
}
// resolveIncludes finds references to undefined labels.
// It then tries to find the code for these labels in the supplied
// include paths. Files should be defined as '<labelname>.dasm'.
func resolveIncludes(ast *parser.AST, includes []string) (err error) {
var labels []*parser.Label
var refs []*parser.Name
var consts []*parser.Name
var funcs []*parser.Function
FindLabels(ast.Root.Children(), &labels)
FindReferences(ast.Root.Children(), &refs)
FindConstants(ast.Root.Children(), &consts)
FindFunctions(ast.Root.Children(), &funcs)
refs = findUndefinedRefs(refs, consts, labels, funcs)
if len(refs) == 0 {
// No undefined references. We're done here.
return
}
if len(includes) == 0 {
// We have unresolved references, but no places to look
// for their implementation. This constitutes a booboo.
return parser.NewParseError(ast.Files[refs[0].File()], refs[0].Line(), refs[0].Col(),
"Undefined reference: %q", refs[0].Data)
}
for i := range refs {
if err = loadInclude(ast, includes, refs[i]); err != nil {
return
}
}
return
}