func()

in klog.go [618:658]

• 37 lines of code
• 4 McCabe index (conditional complexity)

func (l *loggingT) formatHeader(s severity, file string, line int) *buffer {
	now := timeNow()
	if line < 0 {
		line = 0 // not a real line number, but acceptable to someDigits
	}
	if s > fatalLog {
		s = infoLog // for safety.
	}
	buf := l.getBuffer()
	if l.skipHeaders {
		return buf
	}

	// Avoid Fprintf, for speed. The format is so simple that we can do it quickly by hand.
	// It's worth about 3X. Fprintf is hard.
	_, month, day := now.Date()
	hour, minute, second := now.Clock()
	// Lmmdd hh:mm:ss.uuuuuu threadid file:line]
	buf.tmp[0] = severityChar[s]
	buf.twoDigits(1, int(month))
	buf.twoDigits(3, day)
	buf.tmp[5] = ' '
	buf.twoDigits(6, hour)
	buf.tmp[8] = ':'
	buf.twoDigits(9, minute)
	buf.tmp[11] = ':'
	buf.twoDigits(12, second)
	buf.tmp[14] = '.'
	buf.nDigits(6, 15, now.Nanosecond()/1000, '0')
	buf.tmp[21] = ' '
	buf.nDigits(7, 22, pid, ' ') // TODO: should be TID
	buf.tmp[29] = ' '
	buf.Write(buf.tmp[:30])
	buf.WriteString(file)
	buf.tmp[0] = ':'
	n := buf.someDigits(1, line)
	buf.tmp[n+1] = ']'
	buf.tmp[n+2] = ' '
	buf.Write(buf.tmp[:n+3])
	return buf
}