CMake/Source/CTest/cmCTestMultiProcessHandler.cxx

/*============================================================================
  CMake - Cross Platform Makefile Generator
  Copyright 2000-2009 Kitware, Inc., Insight Software Consortium

  Distributed under the OSI-approved BSD License (the "License");
  see accompanying file Copyright.txt for details.

  This software is distributed WITHOUT ANY WARRANTY; without even the
  implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
  See the License for more information.
============================================================================*/
#include "cmCTestMultiProcessHandler.h"
#include "cmProcess.h"
#include "cmStandardIncludes.h"
#include "cmCTest.h"
#include "cmCTestScriptHandler.h"
#include "cmSystemTools.h"
#include <stdlib.h>
#include <stack>
#include <list>
#include <float.h>
#include <math.h>
#include <cmsys/FStream.hxx>
#include <cmsys/SystemInformation.hxx>

class TestComparator
{
public:
  TestComparator(cmCTestMultiProcessHandler* handler) : Handler(handler) {}
  ~TestComparator() {}

  // Sorts tests in descending order of cost
  bool operator() (int index1, int index2) const
    {
    return Handler->Properties[index1]->Cost >
      Handler->Properties[index2]->Cost;
    }

private:
  cmCTestMultiProcessHandler* Handler;
};

cmCTestMultiProcessHandler::cmCTestMultiProcessHandler()
{
  this->ParallelLevel = 1;
  this->TestLoad = 0;
  this->Completed = 0;
  this->RunningCount = 0;
  this->StopTimePassed = false;
  this->HasCycles = false;
  this->SerialTestRunning = false;
}

cmCTestMultiProcessHandler::~cmCTestMultiProcessHandler()
{
}

  // Set the tests
void
cmCTestMultiProcessHandler::SetTests(TestMap& tests,
                                     PropertiesMap& properties)
{
  this->Tests = tests;
  this->Properties = properties;
  this->Total = this->Tests.size();
  // set test run map to false for all
  for(TestMap::iterator i = this->Tests.begin();
      i != this->Tests.end(); ++i)
    {
    this->TestRunningMap[i->first] = false;
    this->TestFinishMap[i->first] = false;
    }
  if(!this->CTest->GetShowOnly())
    {
    this->ReadCostData();
    this->HasCycles = !this->CheckCycles();
    if(this->HasCycles)
      {
      return;
      }
    this->CreateTestCostList();
    }
}

  // Set the max number of tests that can be run at the same time.
void cmCTestMultiProcessHandler::SetParallelLevel(size_t level)
{
  this->ParallelLevel = level < 1 ? 1 : level;
}

void cmCTestMultiProcessHandler::SetTestLoad(unsigned long load)
{
  this->TestLoad = load;
}

//---------------------------------------------------------
void cmCTestMultiProcessHandler::RunTests()
{
  this->CheckResume();
  if(this->HasCycles)
    {
    return;
    }
  this->TestHandler->SetMaxIndex(this->FindMaxIndex());
  this->StartNextTests();
  while(!this->Tests.empty())
    {
    if(this->StopTimePassed)
      {
      return;
      }
    this->CheckOutput();
    this->StartNextTests();
    }
  // let all running tests finish
  while(this->CheckOutput())
    {
    }
  this->MarkFinished();
  this->UpdateCostData();
}

//---------------------------------------------------------
void cmCTestMultiProcessHandler::StartTestProcess(int test)
{
  cmCTestOptionalLog(this->CTest, HANDLER_VERBOSE_OUTPUT,
    "test " << test << "\n", this->Quiet);
  this->TestRunningMap[test] = true; // mark the test as running
  // now remove the test itself
  this->EraseTest(test);
  this->RunningCount += GetProcessorsUsed(test);

  cmCTestRunTest* testRun = new cmCTestRunTest(this->TestHandler);
  if(this->CTest->GetRepeatUntilFail())
    {
    testRun->SetRunUntilFailOn();
    testRun->SetNumberOfRuns(this->CTest->GetTestRepeat());
    }
  testRun->SetIndex(test);
  testRun->SetTestProperties(this->Properties[test]);

  std::string current_dir = cmSystemTools::GetCurrentWorkingDirectory();
  cmSystemTools::ChangeDirectory(this->Properties[test]->Directory);

  // Lock the resources we'll be using
  this->LockResources(test);

  if(testRun->StartTest(this->Total))
    {
    this->RunningTests.insert(testRun);
    }
  else if(testRun->IsStopTimePassed())
    {
    this->StopTimePassed = true;
    delete testRun;
    return;
    }
  else
    {

    for(TestMap::iterator j = this->Tests.begin();
      j != this->Tests.end(); ++j)
      {
      j->second.erase(test);
      }

    this->UnlockResources(test);
    this->Completed++;
    this->TestFinishMap[test] = true;
    this->TestRunningMap[test] = false;
    this->RunningCount -= GetProcessorsUsed(test);
    testRun->EndTest(this->Completed, this->Total, false);
    this->Failed->push_back(this->Properties[test]->Name);
    delete testRun;
    }
  cmSystemTools::ChangeDirectory(current_dir);
}

//---------------------------------------------------------
void cmCTestMultiProcessHandler::LockResources(int index)
{
  this->LockedResources.insert(
      this->Properties[index]->LockedResources.begin(),
      this->Properties[index]->LockedResources.end());

  if (this->Properties[index]->RunSerial)
    {
    this->SerialTestRunning = true;
    }
}

//---------------------------------------------------------
void cmCTestMultiProcessHandler::UnlockResources(int index)
{
  for(std::set<std::string>::iterator i =
      this->Properties[index]->LockedResources.begin();
      i != this->Properties[index]->LockedResources.end(); ++i)
    {
    this->LockedResources.erase(*i);
    }
  if (this->Properties[index]->RunSerial)
    {
    this->SerialTestRunning = false;
    }
}

//---------------------------------------------------------
void cmCTestMultiProcessHandler::EraseTest(int test)
{
  this->Tests.erase(test);
  this->SortedTests.erase(
    std::find(this->SortedTests.begin(), this->SortedTests.end(), test));
}

//---------------------------------------------------------
inline size_t cmCTestMultiProcessHandler::GetProcessorsUsed(int test)
{
  size_t processors =
    static_cast<int>(this->Properties[test]->Processors);
  //If processors setting is set higher than the -j
  //setting, we default to using all of the process slots.
  if (processors > this->ParallelLevel)
    {
    processors = this->ParallelLevel;
    }
  return processors;
}

std::string cmCTestMultiProcessHandler::GetName(int test)
{
  return this->Properties[test]->Name;
}

//---------------------------------------------------------
bool cmCTestMultiProcessHandler::StartTest(int test)
{
  //Check for locked resources
  for(std::set<std::string>::iterator i =
      this->Properties[test]->LockedResources.begin();
      i != this->Properties[test]->LockedResources.end(); ++i)
    {
    if(this->LockedResources.find(*i) != this->LockedResources.end())
      {
      return false;
      }
    }

  // if there are no depends left then run this test
  if(this->Tests[test].empty())
    {
    this->StartTestProcess(test);
    return true;
    }
  // This test was not able to start because it is waiting
  // on depends to run
  return false;
}

//---------------------------------------------------------
void cmCTestMultiProcessHandler::StartNextTests()
{
  size_t numToStart = 0;
  if(this->RunningCount < this->ParallelLevel)
    {
    numToStart = this->ParallelLevel - this->RunningCount;
    }

  if(numToStart == 0)
    {
    return;
    }

  // Don't start any new tests if one with the RUN_SERIAL property
  // is already running.
  if (this->SerialTestRunning)
    {
    return;
    }

  bool allTestsFailedTestLoadCheck = false;
  bool usedFakeLoadForTesting = false;
  size_t minProcessorsRequired = this->ParallelLevel;
  std::string testWithMinProcessors = "";

  cmsys::SystemInformation info;

  unsigned long systemLoad = 0;
  size_t spareLoad = 0;
  if (this->TestLoad > 0)
    {
    // Activate possible wait.
    allTestsFailedTestLoadCheck = true;

    // Check for a fake load average value used in testing.
    if (const char* fake_load_value =
        cmSystemTools::GetEnv("__CTEST_FAKE_LOAD_AVERAGE_FOR_TESTING"))
      {
      usedFakeLoadForTesting = true;
      if (!cmSystemTools::StringToULong(fake_load_value, &systemLoad))
        {
        cmSystemTools::Error("Failed to parse fake load value: ",
                             fake_load_value);
        }
      }
    // If it's not set, look up the true load average.
    else
      {
      systemLoad = static_cast<unsigned long>(ceil(info.GetLoadAverage()));
      }
    spareLoad = (this->TestLoad > systemLoad ?
                 this->TestLoad - systemLoad : 0);

    // Don't start more tests than the spare load can support.
    if (numToStart > spareLoad)
      {
      numToStart = spareLoad;
      }
    }

  TestList copy = this->SortedTests;
  for(TestList::iterator test = copy.begin(); test != copy.end(); ++test)
    {
    // Take a nap if we're currently performing a RUN_SERIAL test.
    if (this->SerialTestRunning)
      {
      break;
      }
    // We can only start a RUN_SERIAL test if no other tests are also running.
    if (this->Properties[*test]->RunSerial && this->RunningCount > 0)
      {
      continue;
      }

    size_t processors = GetProcessorsUsed(*test);
    bool testLoadOk = true;
    if (this->TestLoad > 0)
      {
      if (processors <= spareLoad)
        {
        cmCTestLog(this->CTest, DEBUG,
                    "OK to run " << GetName(*test) <<
                    ", it requires " << processors <<
                    " procs & system load is: " <<
                    systemLoad << std::endl);
        allTestsFailedTestLoadCheck = false;
        }
      else
        {
        testLoadOk = false;
        }
      }

    if (processors <= minProcessorsRequired)
      {
      minProcessorsRequired = processors;
      testWithMinProcessors = GetName(*test);
      }

    if(testLoadOk && processors <= numToStart && this->StartTest(*test))
      {
      if(this->StopTimePassed)
        {
        return;
        }

      numToStart -= processors;
      }
    else if(numToStart == 0)
      {
      break;
      }
    }

  if (allTestsFailedTestLoadCheck)
    {
    cmCTestLog(this->CTest, HANDLER_OUTPUT, "***** WAITING, ");
    if (this->SerialTestRunning)
      {
      cmCTestLog(this->CTest, HANDLER_OUTPUT,
                 "Waiting for RUN_SERIAL test to finish.");
      }
    else
      {
      cmCTestLog(this->CTest, HANDLER_OUTPUT,
                 "System Load: " << systemLoad << ", "
                 "Max Allowed Load: " << this->TestLoad << ", "
                 "Smallest test " << testWithMinProcessors <<
                 " requires " << minProcessorsRequired);
      }
    cmCTestLog(this->CTest, HANDLER_OUTPUT, "*****" << std::endl);

    if (usedFakeLoadForTesting)
      {
      // Break out of the infinite loop of waiting for our fake load
      // to come down.
      this->StopTimePassed = true;
      }
    else
      {
      // Wait between 1 and 5 seconds before trying again.
      cmCTestScriptHandler::SleepInSeconds(
        cmSystemTools::RandomSeed() % 5 + 1);
      }
    }
}

//---------------------------------------------------------
bool cmCTestMultiProcessHandler::CheckOutput()
{
  // no more output we are done
  if(this->RunningTests.empty())
    {
    return false;
    }
  std::vector<cmCTestRunTest*> finished;
  std::string out, err;
  for(std::set<cmCTestRunTest*>::const_iterator i = this->RunningTests.begin();
      i != this->RunningTests.end(); ++i)
    {
    cmCTestRunTest* p = *i;
    if(!p->CheckOutput())
      {
      finished.push_back(p);
      }
    }
  for( std::vector<cmCTestRunTest*>::iterator i = finished.begin();
       i != finished.end(); ++i)
    {
    this->Completed++;
    cmCTestRunTest* p = *i;
    int test = p->GetIndex();

    bool testResult = p->EndTest(this->Completed, this->Total, true);
    if(p->StartAgain())
      {
      this->Completed--; // remove the completed test because run again
      continue;
      }
    if(testResult)
      {
      this->Passed->push_back(p->GetTestProperties()->Name);
      }
    else
      {
      this->Failed->push_back(p->GetTestProperties()->Name);
      }
    for(TestMap::iterator j = this->Tests.begin();
        j != this->Tests.end(); ++j)
      {
      j->second.erase(test);
      }
    this->TestFinishMap[test] = true;
    this->TestRunningMap[test] = false;
    this->RunningTests.erase(p);
    this->WriteCheckpoint(test);
    this->UnlockResources(test);
    this->RunningCount -= GetProcessorsUsed(test);
    delete p;
    }
  return true;
}

//---------------------------------------------------------
void cmCTestMultiProcessHandler::UpdateCostData()
{
  std::string fname = this->CTest->GetCostDataFile();
  std::string tmpout = fname + ".tmp";
  cmsys::ofstream fout;
  fout.open(tmpout.c_str());

  PropertiesMap temp = this->Properties;

  if(cmSystemTools::FileExists(fname.c_str()))
    {
    cmsys::ifstream fin;
    fin.open(fname.c_str());

    std::string line;
    while(std::getline(fin, line))
      {
      if(line == "---") break;
      std::vector<cmsys::String> parts =
        cmSystemTools::SplitString(line, ' ');
      //Format: <name> <previous_runs> <avg_cost>
      if(parts.size() < 3) break;

      std::string name = parts[0];
      int prev = atoi(parts[1].c_str());
      float cost = static_cast<float>(atof(parts[2].c_str()));

      int index = this->SearchByName(name);
      if(index == -1)
        {
        // This test is not in memory. We just rewrite the entry
        fout << name << " " << prev << " " << cost << "\n";
        }
      else
        {
        // Update with our new average cost
        fout << name << " " << this->Properties[index]->PreviousRuns << " "
          << this->Properties[index]->Cost << "\n";
        temp.erase(index);
        }
      }
    fin.close();
    cmSystemTools::RemoveFile(fname);
    }

  // Add all tests not previously listed in the file
  for(PropertiesMap::iterator i = temp.begin(); i != temp.end(); ++i)
    {
    fout << i->second->Name << " " << i->second->PreviousRuns << " "
      << i->second->Cost << "\n";
    }

  // Write list of failed tests
  fout << "---\n";
  for(std::vector<std::string>::iterator i = this->Failed->begin();
      i != this->Failed->end(); ++i)
    {
    fout << i->c_str() << "\n";
    }
  fout.close();
  cmSystemTools::RenameFile(tmpout.c_str(), fname.c_str());
}

//---------------------------------------------------------
void cmCTestMultiProcessHandler::ReadCostData()
{
  std::string fname = this->CTest->GetCostDataFile();

  if(cmSystemTools::FileExists(fname.c_str(), true))
    {
    cmsys::ifstream fin;
    fin.open(fname.c_str());
    std::string line;
    while(std::getline(fin, line))
      {
      if(line == "---") break;

      std::vector<cmsys::String> parts =
        cmSystemTools::SplitString(line, ' ');

      // Probably an older version of the file, will be fixed next run
      if(parts.size() < 3)
        {
        fin.close();
        return;
        }

      std::string name = parts[0];
      int prev = atoi(parts[1].c_str());
      float cost = static_cast<float>(atof(parts[2].c_str()));

      int index = this->SearchByName(name);
      if(index == -1) continue;

      this->Properties[index]->PreviousRuns = prev;
      // When not running in parallel mode, don't use cost data
      if(this->ParallelLevel > 1 &&
         this->Properties[index] &&
         this->Properties[index]->Cost == 0)
        {
        this->Properties[index]->Cost = cost;
        }
      }
    // Next part of the file is the failed tests
    while(std::getline(fin, line))
      {
      if(line != "")
        {
        this->LastTestsFailed.push_back(line);
        }
      }
    fin.close();
    }
}

//---------------------------------------------------------
int cmCTestMultiProcessHandler::SearchByName(std::string name)
{
  int index = -1;

  for(PropertiesMap::iterator i = this->Properties.begin();
      i != this->Properties.end(); ++i)
    {
    if(i->second->Name == name)
      {
      index = i->first;
      }
    }
  return index;
}

//---------------------------------------------------------
void cmCTestMultiProcessHandler::CreateTestCostList()
{
  if(this->ParallelLevel > 1)
    {
    CreateParallelTestCostList();
    }
  else
    {
    CreateSerialTestCostList();
    }
}

//---------------------------------------------------------
void cmCTestMultiProcessHandler::CreateParallelTestCostList()
{
  TestSet alreadySortedTests;

  std::list<TestSet> priorityStack;
  priorityStack.push_back(TestSet());
  TestSet &topLevel = priorityStack.back();

  // In parallel test runs add previously failed tests to the front
  // of the cost list and queue other tests for further sorting
  for(TestMap::const_iterator i = this->Tests.begin();
    i != this->Tests.end(); ++i)
    {
    if(std::find(this->LastTestsFailed.begin(), this->LastTestsFailed.end(),
       this->Properties[i->first]->Name) != this->LastTestsFailed.end())
      {
      //If the test failed last time, it should be run first.
      this->SortedTests.push_back(i->first);
      alreadySortedTests.insert(i->first);
      }
    else
      {
      topLevel.insert(i->first);
      }
    }

  // In parallel test runs repeatedly move dependencies of the tests on
  // the current dependency level to the next level until no
  // further dependencies exist.
  while(priorityStack.back().size())
    {
    TestSet &previousSet = priorityStack.back();
    priorityStack.push_back(TestSet());
    TestSet &currentSet = priorityStack.back();

    for(TestSet::const_iterator i = previousSet.begin();
      i != previousSet.end(); ++i)
      {
      TestSet const& dependencies = this->Tests[*i];
      currentSet.insert(dependencies.begin(), dependencies.end());
      }

    for(TestSet::const_iterator i = currentSet.begin();
      i != currentSet.end(); ++i)
      {
      previousSet.erase(*i);
      }
    }

  // Remove the empty dependency level
  priorityStack.pop_back();

  // Reverse iterate over the different dependency levels (deepest first).
  // Sort tests within each level by COST and append them to the cost list.
  for(std::list<TestSet>::reverse_iterator i = priorityStack.rbegin();
    i != priorityStack.rend(); ++i)
    {
    TestSet const& currentSet = *i;
    TestComparator comp(this);

    TestList sortedCopy;

    sortedCopy.insert(sortedCopy.end(),
                      currentSet.begin(), currentSet.end());

    std::stable_sort(sortedCopy.begin(), sortedCopy.end(), comp);

    for(TestList::const_iterator j = sortedCopy.begin();
      j != sortedCopy.end(); ++j)
      {
      if(alreadySortedTests.find(*j) == alreadySortedTests.end())
        {
        this->SortedTests.push_back(*j);
        alreadySortedTests.insert(*j);
        }
      }
    }
}

//---------------------------------------------------------
void cmCTestMultiProcessHandler::GetAllTestDependencies(
    int test, TestList& dependencies)
{
  TestSet const& dependencySet = this->Tests[test];
  for(TestSet::const_iterator i = dependencySet.begin();
    i != dependencySet.end(); ++i)
    {
    GetAllTestDependencies(*i, dependencies);
    dependencies.push_back(*i);
    }
}

//---------------------------------------------------------
void cmCTestMultiProcessHandler::CreateSerialTestCostList()
{
  TestList presortedList;

  for(TestMap::iterator i = this->Tests.begin();
    i != this->Tests.end(); ++i)
    {
    presortedList.push_back(i->first);
    }

  TestComparator comp(this);
  std::stable_sort(presortedList.begin(), presortedList.end(), comp);

  TestSet alreadySortedTests;

  for(TestList::const_iterator i = presortedList.begin();
    i != presortedList.end(); ++i)
    {
      int test = *i;

      if(alreadySortedTests.find(test) != alreadySortedTests.end())
        {
        continue;
        }

      TestList dependencies;
      GetAllTestDependencies(test, dependencies);

      for(TestList::const_iterator j = dependencies.begin();
        j != dependencies.end(); ++j)
        {
        int testDependency = *j;

        if(alreadySortedTests.find(testDependency) == alreadySortedTests.end())
          {
          alreadySortedTests.insert(testDependency);
          this->SortedTests.push_back(testDependency);
          }
        }

      alreadySortedTests.insert(test);
      this->SortedTests.push_back(test);
    }
}

//---------------------------------------------------------
void cmCTestMultiProcessHandler::WriteCheckpoint(int index)
{
  std::string fname = this->CTest->GetBinaryDir()
    + "/Testing/Temporary/CTestCheckpoint.txt";
  cmsys::ofstream fout;
  fout.open(fname.c_str(), std::ios::app);
  fout << index << "\n";
  fout.close();
}

//---------------------------------------------------------
void cmCTestMultiProcessHandler::MarkFinished()
{
  std::string fname = this->CTest->GetBinaryDir()
    + "/Testing/Temporary/CTestCheckpoint.txt";
  cmSystemTools::RemoveFile(fname);
}

//---------------------------------------------------------
//For ShowOnly mode
void cmCTestMultiProcessHandler::PrintTestList()
{
  this->TestHandler->SetMaxIndex(this->FindMaxIndex());
  int count = 0;

  for (PropertiesMap::iterator it = this->Properties.begin();
       it != this->Properties.end(); ++it)
    {
    count++;
    cmCTestTestHandler::cmCTestTestProperties& p = *it->second;

    //push working dir
    std::string current_dir = cmSystemTools::GetCurrentWorkingDirectory();
    cmSystemTools::ChangeDirectory(p.Directory);

    cmCTestRunTest testRun(this->TestHandler);
    testRun.SetIndex(p.Index);
    testRun.SetTestProperties(&p);
    testRun.ComputeArguments(); //logs the command in verbose mode

    if(!p.Labels.empty()) //print the labels
      {
      cmCTestOptionalLog(this->CTest, HANDLER_VERBOSE_OUTPUT, "Labels:",
        this->Quiet);
      }
    for(std::vector<std::string>::iterator label = p.Labels.begin();
        label != p.Labels.end(); ++label)
      {
      cmCTestOptionalLog(this->CTest, HANDLER_VERBOSE_OUTPUT, " " << *label,
        this->Quiet);
      }
    if(!p.Labels.empty()) //print the labels
      {
      cmCTestOptionalLog(this->CTest, HANDLER_VERBOSE_OUTPUT, std::endl,
        this->Quiet);
      }

    if (this->TestHandler->MemCheck)
      {
      cmCTestOptionalLog(this->CTest, HANDLER_OUTPUT, "  Memory Check",
        this->Quiet);
      }
     else
      {
      cmCTestOptionalLog(this->CTest, HANDLER_OUTPUT, "  Test", this->Quiet);
      }
    std::ostringstream indexStr;
    indexStr << " #" << p.Index << ":";
    cmCTestOptionalLog(this->CTest, HANDLER_OUTPUT,
      std::setw(3 + getNumWidth(this->TestHandler->GetMaxIndex()))
      << indexStr.str(), this->Quiet);
    cmCTestOptionalLog(this->CTest, HANDLER_OUTPUT, " ", this->Quiet);
    cmCTestOptionalLog(this->CTest, HANDLER_OUTPUT,
      p.Name.c_str() << std::endl, this->Quiet);
    //pop working dir
    cmSystemTools::ChangeDirectory(current_dir);
    }

  cmCTestOptionalLog(this->CTest, HANDLER_OUTPUT, std::endl << "Total Tests: "
    << this->Total << std::endl, this->Quiet);
}

void cmCTestMultiProcessHandler::PrintLabels()
{
  std::set<std::string> allLabels;
  for (PropertiesMap::iterator it = this->Properties.begin();
       it != this->Properties.end(); ++it)
    {
    cmCTestTestHandler::cmCTestTestProperties& p = *it->second;
    allLabels.insert(p.Labels.begin(), p.Labels.end());
    }

  if(!allLabels.empty())
    {
    cmCTestOptionalLog(this->CTest, HANDLER_OUTPUT,
      "All Labels:" << std::endl, this->Quiet);
    }
  else
    {
    cmCTestOptionalLog(this->CTest, HANDLER_OUTPUT,
      "No Labels Exist" << std::endl, this->Quiet);
    }
  for(std::set<std::string>::iterator label = allLabels.begin();
      label != allLabels.end(); ++label)
    {
    cmCTestOptionalLog(this->CTest, HANDLER_OUTPUT,
      "  " << *label << std::endl, this->Quiet);
    }
}

//---------------------------------------------------------
void cmCTestMultiProcessHandler::CheckResume()
{
  std::string fname = this->CTest->GetBinaryDir()
      + "/Testing/Temporary/CTestCheckpoint.txt";
  if(this->CTest->GetFailover())
    {
    if(cmSystemTools::FileExists(fname.c_str(), true))
      {
      *this->TestHandler->LogFile << "Resuming previously interrupted test set"
        << std::endl
        << "----------------------------------------------------------"
        << std::endl;

      cmsys::ifstream fin;
      fin.open(fname.c_str());
      std::string line;
      while(std::getline(fin, line))
        {
        int index = atoi(line.c_str());
        this->RemoveTest(index);
        }
      fin.close();
      }
    }
  else if(cmSystemTools::FileExists(fname.c_str(), true))
    {
    cmSystemTools::RemoveFile(fname);
    }
}

//---------------------------------------------------------
void cmCTestMultiProcessHandler::RemoveTest(int index)
{
  this->EraseTest(index);
  this->Properties.erase(index);
  this->TestRunningMap[index] = false;
  this->TestFinishMap[index] = true;
  this->Completed++;
}

//---------------------------------------------------------
int cmCTestMultiProcessHandler::FindMaxIndex()
{
  int max = 0;
  cmCTestMultiProcessHandler::TestMap::iterator i = this->Tests.begin();
  for(; i != this->Tests.end(); ++i)
    {
    if(i->first > max)
      {
      max = i->first;
      }
    }
  return max;
}

//Returns true if no cycles exist in the dependency graph
bool cmCTestMultiProcessHandler::CheckCycles()
{
  cmCTestOptionalLog(this->CTest, HANDLER_VERBOSE_OUTPUT,
             "Checking test dependency graph..." << std::endl, this->Quiet);
  for(TestMap::iterator it = this->Tests.begin();
      it != this->Tests.end(); ++it)
    {
    //DFS from each element to itself
    int root = it->first;
    std::set<int> visited;
    std::stack<int> s;
    s.push(root);
    while(!s.empty())
      {
      int test = s.top();
      s.pop();
      if(visited.insert(test).second)
        {
        for(TestSet::iterator d = this->Tests[test].begin();
            d != this->Tests[test].end(); ++d)
          {
          if(*d == root)
            {
            //cycle exists
            cmCTestLog(this->CTest, ERROR_MESSAGE,
                       "Error: a cycle exists in the test dependency graph "
                       "for the test \"" << this->Properties[root]->Name <<
                       "\".\nPlease fix the cycle and run ctest again.\n");
            return false;
            }
          else
            {
            s.push(*d);
            }
          }
        }
      }
    }
  cmCTestOptionalLog(this->CTest, HANDLER_VERBOSE_OUTPUT,
             "Checking test dependency graph end" << std::endl, this->Quiet);
  return true;
}