static IEnumerable <Checkpoint> EnumCheckpoints(
ITextAccessIterator tai, PlainTextMatcher matcher,
ProgressAndCancellation progressAndCancellation,
LJTraceSource trace)
{
var advanceTime = new Stopwatch();
long advancesCount = 0;
var matchingTime = new Stopwatch();
long matchCount = 0;
for (;;)
{
StringSlice buf = new StringSlice(tai.CurrentBuffer);
for (int startIdx = 0; ;)
{
matchingTime.Start();
var match = matcher.Match(buf, startIdx);
matchingTime.Stop();
++matchCount;
if (!match.HasValue)
{
break;
}
yield return(new Checkpoint()
{
Position = tai.CharIndexToPosition(match.Value.MatchBegin),
EndPosition = tai.CharIndexToPosition(match.Value.MatchEnd),
IsMatch = true
});
startIdx = match.Value.MatchEnd;
progressAndCancellation.CheckTextIterationCancellation();
}
advanceTime.Start();
bool stop = !tai.Advance(Math.Max(0, tai.CurrentBuffer.Length - matcher.MaxMatchLength));
advanceTime.Stop();
++advancesCount;
if (stop)
{
break;
}
yield return(new Checkpoint()
{
EndPosition = tai.CharIndexToPosition(0),
IsMatch = false
});
progressAndCancellation.CheckTextIterationCancellation();
}
trace.Info("Stats: text buffer matching time: {0} ({1} times)",
matchingTime.Elapsed, matchCount);
trace.Info("Stats: text buffer advance time: {0}/{1}={2}",
advanceTime.Elapsed, advancesCount,
TimeSpan.FromTicks(advanceTime.ElapsedTicks / Math.Max(1, advancesCount)));
}
