source: trunk/lib/Gnuplot.cc @ 63

// $Id: Gnuplot.cc 63 2006-01-19 23:07:36Z peter $

#include "Gnuplot.h"

#include <cstdio>
#include <unistd.h>
#include <string>

#include <iostream>

namespace theplu {
namespace svnstat {


  Gnuplot::Gnuplot(void)
    : linestyle_("steps"), pipe_(NULL)
  {
    acquire_program_path("gnuplot");
    if (gnuplot_binary_.empty())
      throw GnuplotException("Can't find gnuplot in your PATH");

    pipe_=popen(gnuplot_binary_.c_str(),"w");
    if (!pipe_)
      throw GnuplotException("Could'nt open connection to gnuplot");
  }


  Gnuplot::~Gnuplot(void)
  {
    if (pclose(pipe_) == -1)
      throw GnuplotException("Problem closing communication to gnuplot");
    for (std::list<std::string>::iterator i=tempfiles_.begin();
         i!=tempfiles_.end(); i++)
      remove(i->c_str());
  }


  void Gnuplot::acquire_program_path(const std::string& progname)
  {
    char* env_path=getenv("PATH");  // is there a need to free this memory?
    if (!env_path)
      throw GnuplotException("Environment variable PATH is not set");

    std::list<std::string> paths;
    tokenizer(env_path,paths);
    for (std::list<std::string>::const_iterator i=paths.begin();
         i!=paths.end(); ++i) {
      std::string tmp((*i) + '/' + progname);
      if (!access(tmp.c_str(),X_OK)) {
        gnuplot_binary_=tmp;
        break;
      }
    }

    if (gnuplot_binary_.empty())
      throw GnuplotException("Cannot find '" + progname + "' in PATH");
  }

  
  void Gnuplot::date_plot(const std::vector<double>& y, 
                          const std::string& format)
  { 
    command(std::string("set xdata time")); 
    command("set timefmt '" + date_input_format_ + "'");
    command("set format x '" + format + "'");
    assert(date_[0].size());
    assert(y.back());
    plot(y,date_,"plot"); 
  }


  void Gnuplot::date_replot(const std::vector<double>& y, 
                            const std::string& format)
  { 
    // Peter is this working, really?
    //command(std::string("set xdata time")); 
    //command("set format x '" + format + "'");
    plot(y,date_,"replot"); 
  }


  void Gnuplot::tokenizer(const std::string& in,
                          std::list<std::string>& tokens,
                          const std::string& delimiters)
  {
    std::string::size_type previous_pos=in.find_first_not_of(delimiters,0);
    std::string::size_type position=in.find_first_of(delimiters,previous_pos);
    while ((std::string::npos!=position) || (std::string::npos!=previous_pos)) {
      tokens.push_back(in.substr(previous_pos, position-previous_pos));
      previous_pos=in.find_first_not_of(delimiters,position);
      position=in.find_first_of(delimiters,previous_pos);
    }
  }


  void Gnuplot::command(std::string cmdstr)
  {
    if (*(cmdstr.rbegin())!='\n')
      cmdstr+='\n';
    fputs(cmdstr.c_str(),pipe_);
    fflush(pipe_);
  }


}} // end of namespace svnstat and namespace theplu