CMake/Source/cmMathCommand.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 "cmMathCommand.h"

#include "cmExprParserHelper.h"

//----------------------------------------------------------------------------
bool cmMathCommand
::InitialPass(std::vector<std::string> const& args, cmExecutionStatus &)
{
  if ( args.size() < 1 )
    {
    this->SetError("must be called with at least one argument.");
    return false;
    }
  const std::string &subCommand = args[0];
  if(subCommand == "EXPR")
    {
    return this->HandleExprCommand(args);
    }
  std::string e = "does not recognize sub-command "+subCommand;
  this->SetError(e.c_str());
  return false;
}

//----------------------------------------------------------------------------
bool cmMathCommand::HandleExprCommand(std::vector<std::string> const& args)
{
  if ( args.size() != 3 )
    {
    this->SetError("EXPR called with incorrect arguments.");
    return false;
    }

  const std::string& outputVariable = args[1];
  const std::string& expression = args[2];
  
  cmExprParserHelper helper;
  if ( !helper.ParseString(expression.c_str(), 0) )
    {
    std::string e = "cannot parse the expression: \""+expression+"\": ";
    e += helper.GetError();
    this->SetError(e.c_str());
    return false;
    }

  char buffer[1024];
  sprintf(buffer, "%d", helper.GetResult());

  this->Makefile->AddDefinition(outputVariable.c_str(), buffer);
  return true;
}