merge.C

Go to the documentation of this file.

/***********************************************************************************\
* (c) Copyright 1998-2025 CERN for the benefit of the LHCb and ATLAS collaborations *
*                                                                                   *
* This software is distributed under the terms of the Apache version 2 licence,     *
* copied verbatim in the file "LICENSE".                                            *
*                                                                                   *
* In applying this licence, CERN does not waive the privileges and immunities       *
* granted to it by virtue of its status as an Intergovernmental Organization        *
* or submit itself to any jurisdiction.                                             *
\***********************************************************************************/
#include <TBranch.h>
#include <TFile.h>
#include <TInterpreter.h>
#include <TKey.h>
#include <TLeaf.h>
#include <TROOT.h>
#include <TSystem.h>
#include <TTree.h>
#include <TTreeCloner.h>
#include <TUUID.h>
#include <libgen.h>
#include <map>
#include <memory>
#include <string>
#include <vector>
 
// Forward declarations
class TTree;
class TFile;
class TBranch;
 
/*
 * Gaudi namespace declaration
 */
namespace Gaudi {
 
  typedef int MergeStatus;
  enum MergeStatusEnum { MERGE_ERROR = 0, MERGE_SUCCESS = 1 };
 
  struct ContainerSection {
    int start;
    int length;
  };

  class RootDatabaseMerger {
 
    typedef std::vector<ContainerSection>            ContainerSections;
    typedef std::map<std::string, ContainerSections> DatabaseSections;
 
    DatabaseSections       m_sections;
    std::unique_ptr<TFile> m_output;
    bool                   m_treeSections = false;
 
    union uuid_data {
      unsigned char  buf[16];
      unsigned short sbuf[8];
      unsigned int   ibuf[4];
    };
 
  public:
    RootDatabaseMerger();
    virtual ~RootDatabaseMerger();
    bool exists( const std::string& fid ) const;
    MergeStatus create( const std::string& fid );
    MergeStatus attach( const std::string& fid );
    MergeStatus close();
    MergeStatus merge( const std::string& fid );
    void dumpSections();
    MergeStatus saveSections();
    MergeStatus createFID();

    MergeStatus copyAllTrees( TFile* source );
    MergeStatus copyTree( TFile* source, const std::string& name );
    MergeStatus copyBranch( TTree* src_tree, TTree* out_tree, const std::string& name );
    MergeStatus copyRefs( TFile* source, const std::string& name );
    MergeStatus addSections( TTree* in, TTree* out );
  };
} // End namespace Gaudi
 
using namespace Gaudi;
using namespace std;
 
namespace {
  static bool s_dbg = true;
}

RootDatabaseMerger::RootDatabaseMerger() = default;

RootDatabaseMerger::~RootDatabaseMerger() { close(); }

bool RootDatabaseMerger::exists( const std::string& fid ) const {
  Bool_t result = gSystem->AccessPathName( fid.c_str(), kFileExists );
  // if ( s_dbg ) ::printf("File %s %s!\n",fid.c_str(),result == kFALSE ? "EXISTS" : "DOES NOT EXIST");
  return result == kFALSE;
}

MergeStatus RootDatabaseMerger::attach( const string& file_id ) {
  const char* fid = file_id.c_str();
  if ( m_output ) {
    ::printf( "+++ Another output file %s is already open. Request denied.\n", m_output->GetName() );
    return MERGE_ERROR;
  } else if ( !exists( file_id ) ) {
    ::printf( "+++ Cannot attach output file %s --- file does not exist.\n", fid );
    return MERGE_ERROR;
  }
  m_output.reset( TFile::Open( fid, "UPDATE" ) );
  if ( m_output && !m_output->IsZombie() ) {
    // if ( s_dbg ) ::printf("+++ Update output file %s.\n",fid);
    // if ( s_dbg ) ::printf("+++ Update output file.\n");
    return MERGE_SUCCESS;
  }
  ::printf( "+++ Failed to open new output file %s.\n", fid );
  return MERGE_ERROR;
}

MergeStatus RootDatabaseMerger::create( const string& fid ) {
  if ( m_output ) {
    ::printf( "+++ Another output file %s is already open. Request denied.\n", m_output->GetName() );
    return MERGE_ERROR;
  } else if ( exists( fid ) ) {
    ::printf( "+++ Cannot create output file %s --- file already exists.\n", fid.c_str() );
    return MERGE_ERROR;
  }
  m_output.reset( TFile::Open( fid.c_str(), "RECREATE" ) );
  if ( m_output && !m_output->IsZombie() ) {
    TTree* t1 = new TTree( "Sections", "Root Section data" );
    TTree* t2 = new TTree( "Refs", "Root Section data" );
    if ( t1 && t2 ) {
      t1->Branch( "Sections", 0, "Sections/C" );
      t2->Branch( "Links", 0, "Links/C" );
      t2->Branch( "Params", 0, "Params/C" );
      t2->Branch( "Databases", 0, "Databases/C" );
      t2->Branch( "Containers", 0, "Containers/C" );
      if ( s_dbg ) ::printf( "+++ Opened new output file %s.\n", fid.c_str() );
      return MERGE_SUCCESS;
    }
  }
  ::printf( "+++ Failed to open new output file %s.\n", fid.c_str() );
  return MERGE_ERROR;
}

MergeStatus RootDatabaseMerger::createFID() {
  static const char* fmt = "FID=%08lX-%04hX-%04hX-%02hhX%02hhX-%02hhX%02hhX%02hhX%02hhX%02hhX%02hhX";
  if ( m_output ) {
    TTree* t = (TTree*)m_output->Get( "Refs" );
    if ( t ) {
      uuid_data d;
      char      text[256];
      TUUID     uuid;
      TBranch*  b = t->GetBranch( "Params" );
      if ( b ) {
        uuid.GetUUID( d.buf );
        sprintf( text, fmt, d.ibuf[0], d.sbuf[2], d.sbuf[3], d.buf[8], d.buf[9], d.buf[10], d.buf[11], d.buf[12],
                 d.buf[13], d.buf[14], d.buf[15] );
        b->SetAddress( text );
        b->Fill();
        t->Write();
        if ( s_dbg ) ::printf( "+++ Added new GUID %s to merge file.\n", text );
        return MERGE_SUCCESS;
      }
    }
  }
  ::printf( "+++ Failed to add new GUID to merge file.\n" );
  return MERGE_ERROR;
}

MergeStatus RootDatabaseMerger::close() {
  if ( m_output ) {
    // if ( s_dbg ) ::printf("+++ Closing merge file: %s.\n",m_output->GetName());
    if ( s_dbg ) ::printf( "+++ Closing merge file.\n" );
    m_output->Write();
    m_output->Purge();
    if ( s_dbg ) m_output->ls();
    m_output->Close();
    m_output.reset();
  }
  return MERGE_SUCCESS;
}

MergeStatus RootDatabaseMerger::saveSections() {
  if ( m_output ) {
    int    nb, total = 0, nbytes = 0;
    char   text[1024];
    TTree* t = (TTree*)m_output->Get( "Sections" );
    if ( t ) {
      TBranch* b = t->GetBranch( "Sections" );
      if ( b ) {
        b->SetAddress( text );
        for ( const auto& i : m_sections ) {
          string cont = i.first;
          for ( const auto& j : i.second ) {
            ::sprintf( text, "[CNT=%s][START=%d][LEN=%d]", cont.c_str(), j.start, j.length );
            nb = t->Fill();
            ++total;
            if ( nb > 0 )
              nbytes += nb;
            else
              ::printf( "+++ Failed to update Sections tree with new entries. [WRITE_ERROR]\n" );
          }
        }
        ::sprintf( text, "[END-OF-SECTION]" );
        nb = t->Fill();
        ++total;
        if ( nb > 0 )
          nbytes += nb;
        else
          ::printf( "+++ Failed to update Sections branch with new entries. [WRITE_ERROR]\n" );
        t->Write();
        if ( s_dbg ) ::printf( "+++ Added %d Sections entries with %d bytes in total.\n", total, nbytes );
        return MERGE_SUCCESS;
      }
      ::printf( "+++ Failed to update Sections tree with new entries. [NO_OUTPUT_BRANCH]\n" );
      return MERGE_ERROR;
    }
    ::printf( "+++ Failed to update Sections tree with new entries. [NO_OUTPUT_TREE]\n" );
    return MERGE_ERROR;
  }
  ::printf( "+++ Failed to update Sections tree with new entries. [NO_OUTPUT_FILE]\n" );
  return MERGE_ERROR;
}

void RootDatabaseMerger::dumpSections() {
  for ( const auto& i : m_sections ) {
    int    cnt    = 0;
    string prefix = i.first;
    for ( const auto& j : i.second ) {
      char text[1024];
      ::sprintf( text, "['%s'][%d]", prefix.c_str(), cnt++ );
      if ( s_dbg ) {
        ::printf( "+++ section %-55s Start:%8d ... %8d [%d entries]\n", text, j.start, j.start + j.length, j.length );
      }
    }
  }
}

MergeStatus RootDatabaseMerger::merge( const string& fid ) {
  if ( m_output ) {
    std::unique_ptr<TFile> source{ TFile::Open( fid.c_str() ) };
    if ( source && !source->IsZombie() ) {
      size_t idx = fid.rfind( '/' );
      ::printf( "+++ Start merging input file:%s\n",
                idx != string::npos ? fid.substr( idx + 1 ).c_str() : fid.c_str() );
      if ( copyAllTrees( source.get() ) == MERGE_SUCCESS ) {
        if ( copyRefs( source.get(), "Refs" ) == MERGE_SUCCESS ) {
          source->Close();
          return MERGE_SUCCESS;
        }
      }
    }
    ::printf( "+++ Cannot open input file:%s\n", fid.c_str() );
    m_output->cd();
    return MERGE_ERROR;
  }
  ::printf( "+++ No valid output file present. Merge request refused for fid:%s.\n", fid.c_str() );
  return MERGE_ERROR;
}

MergeStatus RootDatabaseMerger::addSections( TTree* in, TTree* out ) {
  if ( m_treeSections ) {
    ContainerSection s;
    s.start  = (int)( out ? out->GetEntries() : 0 );
    s.length = (int)in->GetEntries();
    m_sections[in->GetName()].push_back( s );
    return MERGE_SUCCESS;
  }
 
  TObjArray* a_in = in->GetListOfBranches();
  for ( int i = 0, n = a_in->GetLast(); i < n; ++i ) {
    TBranch* b_in  = (TBranch*)a_in->At( i );
    TBranch* b_out = out ? out->GetBranch( b_in->GetName() ) : 0;
    if ( !out || b_out ) {
      ContainerSection s;
      s.start  = (int)( b_out ? b_out->GetEntries() : 0 );
      s.length = (int)b_in->GetEntries();
      m_sections[b_in->GetName()].push_back( s );
      continue;
    }
    ::printf( "+++ Cannot merge incompatible branches:%s.\n", b_in->GetName() );
    return MERGE_ERROR;
  }
  return MERGE_SUCCESS;
}

MergeStatus RootDatabaseMerger::copyBranch( TTree* src_tree, TTree* out_tree, const string& name ) {
  char     text[4096];
  TBranch* s = src_tree->GetBranch( name.c_str() );
  TBranch* o = out_tree->GetBranch( name.c_str() );
  if ( s && o ) {
    s->SetAddress( text );
    o->SetAddress( text );
    for ( Long64_t i = 0, n = s->GetEntries(); i < n; ++i ) {
      s->GetEntry( i );
      o->Fill();
    }
    return MERGE_SUCCESS;
  }
  return MERGE_ERROR;
}

MergeStatus RootDatabaseMerger::copyAllTrees( TFile* source ) {
  TIter nextkey( source->GetListOfKeys() );
  // m_treeSections = true;
  for ( TKey* key = (TKey*)nextkey(); key; key = (TKey*)nextkey() ) {
    const char* classname = key->GetClassName();
    TClass*     cl        = gROOT->GetClass( classname );
    if ( !cl ) continue;
    if ( cl->InheritsFrom( "TTree" ) ) {
      string name = key->GetName();
      if ( name == "Refs" ) continue;
      m_treeSections = 0 == ::strncmp( key->GetName(), "<local>_", 7 );
      printf( "+++ Copy Tree:%s %d\n", name.c_str(), int( m_treeSections ) );
      if ( copyTree( source, name ) != MERGE_SUCCESS ) {
        m_treeSections = false;
        return MERGE_ERROR;
      }
    }
  }
  m_treeSections = false;
  return MERGE_SUCCESS;
}

MergeStatus RootDatabaseMerger::copyTree( TFile* source, const string& name ) {
  TTree* src_tree = (TTree*)source->Get( name.c_str() );
  if ( src_tree ) {
    Long64_t src_entries = src_tree->GetEntries();
    TTree*   out_tree    = (TTree*)m_output->Get( name.c_str() );
    m_output->cd();
    if ( 0 == src_tree->GetEntries() ) { src_tree->SetEntries( 1 ); }
    addSections( src_tree, out_tree );
    if ( !out_tree ) {
      out_tree = src_tree->CloneTree( -1, "fast" );
      if ( s_dbg ) ::printf( "+++ Created new Tree %s.\n", out_tree->GetName() );
      out_tree->Write();
      delete out_tree;
      return MERGE_SUCCESS;
    }
    m_output->GetObject( name.c_str(), out_tree );
    TTreeCloner cloner( src_tree, out_tree, "fast" );
    if ( cloner.IsValid() ) {
      Long64_t out_entries = out_tree->GetEntries();
      out_tree->SetEntries( out_entries + src_entries );
      Bool_t res = cloner.Exec();
      if ( s_dbg ) ::printf( "+++ Merged tree: %s res=%d\n", out_tree->GetName(), res );
      out_tree->Write();
      delete out_tree;
      return MERGE_SUCCESS;
    } else {
      // Fast cloning is not possible for this input TTree.
      // ... see TTree::CloneTree for example of recovery code ...
      ::printf( "+++ Got a tree where fast cloning is not possible -- operation failed.\n" );
      return MERGE_ERROR;
    }
#if 0
    Long64_t nb = out_tree->CopyEntries(src_tree,-1,"fast");
    Long64_t out_entries = out_tree->GetEntries();
    out_tree->SetEntries(out_entries+src_entries);
    out_tree->Write();
    if ( s_dbg ) ::printf("+++ Merged tree: %s res=%lld\n",out_tree->GetName(),nb);
    return MERGE_SUCCESS;
#endif
  }
  return MERGE_ERROR;
}

MergeStatus RootDatabaseMerger::copyRefs( TFile* source, const string& name ) {
  TTree* src_tree = (TTree*)source->Get( name.c_str() );
  if ( src_tree ) {
    TTree* out_tree = (TTree*)m_output->Get( name.c_str() );
    if ( out_tree ) {
      addSections( src_tree, out_tree );
      copyBranch( src_tree, out_tree, "Links" );
      copyBranch( src_tree, out_tree, "Params" );
      copyBranch( src_tree, out_tree, "Containers" );
      copyBranch( src_tree, out_tree, "Databases" );
      out_tree->Write();
      return MERGE_SUCCESS;
    }
  }
  return MERGE_ERROR;
}
 
int merge( const char* target, const char* source, bool fixup = false, bool dbg = true ) {
  s_dbg = dbg;
  // s_dbg = true;
#if 0
  static bool first = true;
  if ( first ) {
    first = false;
    gSystem->Load("libCintex");
    gInterpreter->ProcessLine("Cintex::Enable()");
    //gSystem->Load("libGaudiKernelDict");
    //gSystem->Load("libGaudiTestSuiteDict");
  }
#endif
  // printf("+++ Target:%s\n+++ Source file:%s Fixup:%s Dbg:%s\n",
  //     target,source, fixup ? "YES" : "NO",s_dbg ? "YES" : "NO");
  RootDatabaseMerger m;
  MergeStatus        ret = m.exists( target ) ? m.attach( target ) : m.create( target );
  if ( ret == MERGE_SUCCESS ) {
    ret = m.merge( source );
    if ( ret == MERGE_SUCCESS ) {
      m.dumpSections();
      if ( fixup ) m.createFID();
      m.saveSections();
      return m.close();
    }
  }
  ::printf( "+++ Cannot open output file:%s\n", target );
  return 0;
}