configExample.cpp

Example program demonstrating the use of ArConfigThis program shows how to use ArConfig to store configuration parameters and load/save them from a file.

The ArNetworking library includes server classes that will let you use a remote client such as MobileEyes to view and change the configuration. See ArNetworking documentation and examples.

/*
Adept MobileRobots Robotics Interface for Applications (ARIA)
Copyright (C) 2004, 2005 ActivMedia Robotics LLC
Copyright (C) 2006, 2007, 2008, 2009, 2010 MobileRobots Inc.
Copyright (C) 2011, 2012, 2013 Adept Technology

     This program is free software; you can redistribute it and/or modify
     it under the terms of the GNU General Public License as published by
     the Free Software Foundation; either version 2 of the License, or
     (at your option) any later version.

     This program is distributed in the hope that it will be useful,
     but WITHOUT ANY WARRANTY; without even the implied warranty of
     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
     GNU General Public License for more details.

     You should have received a copy of the GNU General Public License
     along with this program; if not, write to the Free Software
     Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA

If you wish to redistribute ARIA under different terms, contact 
Adept MobileRobots for information about a commercial version of ARIA at 
robots@mobilerobots.com or 
Adept MobileRobots, 10 Columbia Drive, Amherst, NH 03031; +1-603-881-7960
*/
#include "Aria.h"

class ConfigExample
{
  ArConfig* myConfig;
  int myIntParam;
  double myDoubleParam;
  bool myBoolParam;
  char myStringParam[256];
  ArRetFunctorC<bool, ConfigExample> myProcessConfigCB;

public:
  ConfigExample():
    myIntParam(0),
    myDoubleParam(0.5),
    myBoolParam(false),
    myProcessConfigCB(this, &ConfigExample::processConfigFile)
  {
    // The global Aria class contains an ArConfig object.  You can create
    // other instances of ArConfig, but this is how you can share one ArConfig
    // among various program modules.
    // If you want to store a config parameter in ArConfig, first you must add 
    // it to the ArConfig object.  Parameters are stored in sections, and
    // they affect a variable via a pointer provided in an ArConfigArg
    // object:
    ArConfig* config = Aria::getConfig();
    config->setSectionComment("Example Section", "Contains parameters created by the configExample");

    // Add an integer which ranges from -10 to 10:
    config->addParam( ArConfigArg("ExampleIntegerParameter", &myIntParam, "Example parameter integer.", -10, 10), "Example Section", ArPriority::NORMAL);
    
    // Add a floating point number which ranges from 0.0 to 1.0:
    config->addParam( ArConfigArg("ExampleDoubleParameter", &myDoubleParam, "Example double precision floating point number.", 0.0, 1.0), "Example Section", ArPriority::NORMAL);

    // Essential parameters can be placed in the "Important" priority level:
    config->addParam( ArConfigArg("ExampleBoolParameter", &myBoolParam, "Example boolean parameter."), "Example Section", ArPriority::IMPORTANT);

    // Unimportant parameters can be placed in the "Trivial" priority level:
    myStringParam[0] = '\0';  // make string empty
    config->addParam( ArConfigArg("ExampleStringParameter", myStringParam, "Example string parameter.", 256), "Example Section", ArPriority::TRIVIAL);

    // You can set a callback to be invoked when the configuration changes, in
    // case you need to respond to any changes in the parameter values:
    config->addProcessFileCB(&myProcessConfigCB, 0);
  }

  
  // Method called by config process callback when a new file is loaded.
  // It can return false to indicate an error, or true to indicate no error.
  bool processConfigFile() 
  {
    ArLog::log(ArLog::Normal, "configExample: Config changed. New values: int=%d, float=%f, bool=%s, string=\"%s\".", myIntParam, myDoubleParam, myBoolParam?"true":"false", myStringParam);
    return true;
  }
};
  
int main(int argc, char **argv)
{
  Aria::init();
  ArArgumentParser argParser(&argc, argv);
  argParser.loadDefaultArguments();
  if (argc < 2 || !Aria::parseArgs() || argParser.checkArgument("-help"))
  {
    ArLog::log(ArLog::Terse, "configExample usage: configExample <config file>.\nFor example, \"configExample examples/configExample.cfg\".");
    Aria::logOptions();
    Aria::exit(1);
    return 1;
  }
  
  // Object containing config parameters, and responding to changes:
  ConfigExample configExample;

  // Load a config file given on the command line into the global 
  // ArConfig object kept by Aria.  Normally ArConfig expects config
  // files to be in the main ARIA directory (i.e. /usr/local/Aria or
  // a directory specified by the $ARIA environment variable).
  char error[512];
  const char* filename = argParser.getArg(1);
  ArConfig* config = Aria::getConfig();
  ArLog::log(ArLog::Normal, "configExample: loading configuration file \"%s\"...", filename);
  if (! config->parseFile(filename, true, false, error, 512) )
  {
    ArLog::log(ArLog::Terse, "configExample: Error loading configuration file \"%s\" %s. Try \"examples/configExample.cfg\".", filename, error);
    Aria::exit(-1);
    return -1;
  }

  ArLog::log(ArLog::Normal, "configExample: Loaded configuration file \"%s\".", filename);
  
  // After changing a config value, you should invoke the callbacks:
  ArConfigSection* section = config->findSection("Example Section");
  if (section)
  {
    ArConfigArg* arg = section->findParam("ExampleBoolParameter");
    if (arg)
    {
      arg->setBool(!arg->getBool());
      if (! config->callProcessFileCallBacks(false, error, 512) )
      {
        ArLog::log(ArLog::Terse, "configExample: Error processing modified config: %s.", error);
      }
      else
      {
        ArLog::log(ArLog::Normal, "configExample: Successfully modified config and invoked callbacks.");
      }
    }
  }

  // You can save the configuration as well:
  ArLog::log(ArLog::Normal, "configExample: Saving configuration...");
  if(!config->writeFile(filename))
  {
    ArLog::log(ArLog::Terse, "configExample: Error saving configuration to file \"%s\"!", filename);
  }

  // end of program.
  ArLog::log(ArLog::Normal, "configExample: end of program.");
  Aria::exit(0);
  return 0;
}