From 66964465fcca61ba7e034a50bd11e18dd535ceb1 Mon Sep 17 00:00:00 2001
From: cvetan <cvetan@f7af4fe6-9843-0410-8265-dc069ae4e863>
Date: Fri, 17 Jul 2009 13:06:29 +0000
Subject: [PATCH] New method to access certain event number by using also its
 event-id. Useful in case an event selection/filtering is used.

---
 RAW/AliRawReader.cxx | 37 ++++++++++++++++++++++++++++++++++---
 RAW/AliRawReader.h   |  4 ++++
 2 files changed, 38 insertions(+), 3 deletions(-)

diff --git a/RAW/AliRawReader.cxx b/RAW/AliRawReader.cxx
index 1fc4a057698..922958bc4cd 100644
--- a/RAW/AliRawReader.cxx
+++ b/RAW/AliRawReader.cxx
@@ -541,10 +541,19 @@ Bool_t AliRawReader::ReadNextChar(UChar_t& data)
   return kTRUE;
 }
 
-Bool_t  AliRawReader::GotoEvent(Int_t /*event*/)
+Bool_t  AliRawReader::GotoEvent(Int_t event)
 {
-  Error("GotoEvent","Method not implemented! Nothing done");
-  return kFALSE;
+  // Random access to certain
+  // event index. Could be very slow
+  // for some non-root raw-readers.
+  // So it should be reimplemented there.
+  if (event < fEventNumber) RewindEvents();
+
+  while (fEventNumber < event) {
+    if (!NextEvent()) return kFALSE;
+  }
+
+  return kTRUE;
 }
 
 Int_t AliRawReader::CheckData() const
@@ -701,3 +710,25 @@ void AliRawReader::AddErrorLog(AliRawDataErrorLog::ERawDataErrorLevel level,
     if (prevLog) prevLog->AddCount();
 
 }
+
+Bool_t AliRawReader::GotoEventWithID(Int_t event, 
+				     UInt_t period,
+				     UInt_t orbitID,
+				     UShort_t bcID)
+{
+  // Go to certain event number by
+  // checking the event ID.
+  // Useful in case event-selection
+  // is applied and the 'event' is
+  // relative
+  if (!GotoEvent(event)) return kFALSE;
+
+  while (GetBCID()    != period  ||
+	 GetOrbitID() != orbitID ||
+	 GetPeriod()  != bcID) {
+    if (!NextEvent()) return kFALSE;
+  }
+
+  return kTRUE;
+}
+
diff --git a/RAW/AliRawReader.h b/RAW/AliRawReader.h
index 6ed347e4015..85cdfa54163 100644
--- a/RAW/AliRawReader.h
+++ b/RAW/AliRawReader.h
@@ -123,6 +123,10 @@ class AliRawReader: public TObject {
     virtual Bool_t   NextEvent() = 0;
     virtual Bool_t   RewindEvents() = 0;
     virtual Bool_t   GotoEvent(Int_t event);
+    virtual Bool_t   GotoEventWithID(Int_t event,
+				     UInt_t period,
+				     UInt_t orbitID,
+				     UShort_t bcID);
     virtual Int_t    GetEventIndex() const { return -1; }
     virtual Int_t    GetNumberOfEvents() const { return -1; }
 
-- 
2.39.3