// read a line from the readByter (only "\n" and "\r\n" are recognized as line endings)
func newLine(rb readByter, num int) (l *line, err os.Error) {
buf := new([256]byte)
pos := 0
// read almost a full line into the buffer
c, e := rb.ReadByte()
for ; e == nil && c != '\n'; c, e = rb.ReadByte() {
if !legalChar(c) {
common.HandleFatal(fmt.Sprintf("Unable to handle non-ASCII character %d in line %d!", c, num))
}
putChar(c, buf, pos, num)
pos++
}
// handle last character
if e == os.EOF {
putChar(common.EOF, buf, pos, num)
} else if e != nil {
return nil, e
} else {
putChar(c, buf, pos, num)
}
return &line{num, buf[0 : pos+1]}, nil
}
func any2line(any interface{}) *line {
line, ok := any.(*line)
if !ok {
common.HandleFatal("Internal error (not a line)!")
}
return line
}
// read a new line and append it to the source buffer
func (sb *SrcBuffer) readNewLine() {
if sb.buf.Len() > MAX_BUFFER_LINES {
sb.Error("Buffer overflow; please break up your code into smaller pieces");
}
num := 0;
if sb.curLine != nil {
num = sb.curLine.num + 1;
}
line, err := newLine(sb.source, num);
if err != nil {
common.HandleFatal(fmt.Sprintf("While reading line %d: %v", num+1, err.String()));
}
sb.curLine = line;
sb.curElem = sb.buf.PushBack(line);
}
// Error - Handle errors by writing a description to STDERR and exiting.
func (sb *SrcBuffer) Error(msg string) {
common.HandleFatal(
common.MakeErrString(msg, sb.curLine.num, sb.curLine.String(), sb.curCol, 1)
);
}
func (piece *SrcPiece) Error(msg string) {
common.HandleFatal(common.MakeErrString(msg, piece.StartLine(), piece.WholeLine(),
piece.StartColumn(), len(piece.Content()) )
);
}
func putChar(c byte, buf []byte, pos int, num int) {
if pos >= len(buf) {
common.HandleFatal(fmt.Sprintf("Line %d is longer than %d bytes!", num, len(buf)))
}
buf[pos] = c
}