delayed newline counting

Fix a lot of corning cases for correct newline counting, but not
the ones where the closing brace is solely on a newline.

parse_test.go

@@ -507,11 +507,17 @@ func TestLineNumberError(t *testing.T) {
 // Test with no known RR on the line
 func TestLineNumberError2(t *testing.T) {
 	s := "example.com. 1000 SO master.example.com. admin.example.com. 1 4294967294 4294967293 4294967295 100"
+	s = "example.com 1000 IN TALINK a.example.com. b.\\@example.com."
+	s = "example.com 1000 IN TALINK ( a.example.com. b.\\@example.com. )"
+	s = `example.com 1000 IN TALINK ( a.example.com. 
+			b.\@example.com. )`
+	s = `example.com 1000 IN TALINK ( a.example.com.  b.\@example.com.
+		)`
 	_, err := NewRR(s)
 	if err == nil {
 		t.Fail()
 	} else {
-		//		fmt.Printf("%s\n", err.Error())
+		fmt.Printf("%s\n", err.Error())
 	}
 }
 

scanner.go

@@ -11,7 +11,7 @@ import (
 type scan struct {
 	src      *bufio.Reader
 	position scanner.Position
-	eof      int // have we just seen an EOF (0 no, 1 yes)
+	eof      bool // Have we just seen a eof
 }
 
 func scanInit(r io.Reader) *scan {
@@ -27,11 +27,16 @@ func (s *scan) tokenText() (byte, error) {
 	if err != nil {
 		return c, err
 	}
-	s.eof = 0
-	if c == '\n' {
+	// delay the newline handling until the next token is delivered,
+	// fixes off-by-one errors when reporting a parse error.
+	if s.eof == true {
 		s.position.Line++
 		s.position.Column = 0
-		s.eof = 1
+		s.eof = false
+	}
+	if c == '\n' {
+		s.eof = true
+		return c, nil
 	}
 	s.position.Column++
 	return c, nil

zscan.go

@@ -72,11 +72,8 @@ func (e *ParseError) Error() (s string) {
 	if e.file != "" {
 		s = e.file + ": "
 	}
-	// the -e.lex.eof is used for a file line number correction. The error
-	// we are printing happend on the line N, but the tokenizer already
-	// saw the \n and incremented the linenumber counter
 	s += "dns: " + e.err + ": " + strconv.QuoteToASCII(e.lex.token) + " at line: " +
-		strconv.Itoa(e.lex.line-e.lex.eof) + ":" + strconv.Itoa(e.lex.column)
+		strconv.Itoa(e.lex.line) + ":" + strconv.Itoa(e.lex.column)
 	return
 }
 
@@ -86,7 +83,6 @@ type lex struct {
 	value  uint8  // Value: _STRING, _BLANK, etc.
 	line   int    // Line in the file
 	column int    // Column in the file
-	eof    int    // Has the tokenizer just seen a newline (0 no, 1 yes)
 	torc   uint16 // Type or class as parsed in the lexer, we only need to look this up in the grammar
 }
 
@@ -451,7 +447,6 @@ func zlexer(s *scan, c chan lex) {
 	for err == nil {
 		l.column = s.position.Column
 		l.line = s.position.Line
-		l.eof = s.eof
 		if stri > maxTok {
 			l.token = "tok length insufficient for parsing"
 			l.err = true