/// <summary>
/// Updates the line index centred around 'filepos'.
/// If 'filepos' is within the current byte range of 'm_line_index' then an incremental search
/// for lines is done in the direction needed to re-centre the line list around 'filepos'.
/// If 'reload' is true a full rebuild of the cache is done</summary>
public void Build(long filepos, bool reload, IList <IFilter> filters)
{
// Incremental updates cannot interrupt full reloads
if (m_reload_in_progress && reload == false)
{
return;
}
m_reload_in_progress = reload;
// Increment the build issue number to cancel any previous builds
Interlocked.Increment(ref m_issue);
var issue = m_issue;
// Make a copy of the current state
var state = m_state;
// The index that 'filepos' would have in 'm_line_index'.
// -1 if 'filepos' is before the current cached range,
// or 'm_line_index.Count' if after
state.m_index_centre = FindIndex(m_line_index, filepos);
state.m_index_count = m_line_index.Count;
// Make a copy of the filters
state.m_filters = new List <IFilter>(filters);
// Start a build in a worker thread
ThreadPool.QueueUserWorkItem(BuildWorker);
void BuildWorker(object _)
{
try
{
// Open a new stream to the log data
using (var src = Src.OpenStream())
{
// Determine new state properties of the file
state.m_fileend = src.Length;
state.m_filepos = Math_.Clamp(filepos, 0, state.m_fileend);
// Do the update
var lines = BuildAsync(ref state, src, reload, Progress);
// Add the lines to the line index
m_dispatcher.BeginInvoke(new Action(() =>
{
MergeResults(state, lines, reload, Progress);
}));
}
}
catch (Exception ex)
{
m_dispatcher.BeginInvoke(new Action(() =>
{
BuildError?.Invoke(this, new BuildErrorEventArgs(ex));
}));
}
finally
{
m_dispatcher.BeginInvoke(new Action(() =>
{
if (!Progress(1, 1))
{
return;
}
m_reload_in_progress = false;
}));
}
}
bool Progress(long scanned, long length)
{
m_dispatcher.BeginInvoke(new Action(() =>
{
if (IsBuildCancelled(issue))
{
return;
}
BuildProgress?.Invoke(this, new BuildProgressEventArgs(scanned, length));
}));
return(!IsBuildCancelled(issue));
}
}
