Configuration Initialiser

The base configuration initialiser flx::run::flx_config::init

This method of the configuration class provides the basic environmental initialisation. It first tries to grab the program arguments using the callback get_flx_args_config which was passed to the constructor, exiting if it returns 1, an error. Otherwise it sets various configuration based on environment variables, or defaults if they're not present.

The first variable obtained is a general debug control variable. The values are printed to standard error if that variable is set.

This method is called by flx_world::setup method to initialise the configuration object. It is a universal method which cannot be replaced.

int
flx_config::init(int argc, char **argv) {
  if(get_flx_args_config(argc, argv, this)) return 1;

  debug = (bool)egetv("FLX_DEBUG", debug);
  if (debug) {
    fprintf(stderr,
      "[FLX_DEBUG] Debug enabled for %s link program\n",
      static_link ? "static" : "dynamic");
  }

  debug_threads = (bool)egetv("FLX_DEBUG_THREADS", debug);
  if (debug_threads) {
    fprintf(stderr, "[FLX_DEBUG_THREADS] Threads debug enabled\n");
  }

  debug_allocations = (bool)egetv("FLX_DEBUG_ALLOCATIONS", debug);
  if (debug_allocations) {
    fprintf(stderr, "[FLX_DEBUG_ALLOCATIONS] Allocation debug enabled\n");
  }

  debug_collections = (bool)egetv("FLX_DEBUG_COLLECTIONS", debug);
  if (debug_collections)
  {
    fprintf(stderr, "[FLX_DEBUG_COLLECTIONS] Collection debug enabled\n");
  }

  report_collections = (bool)egetv("FLX_REPORT_COLLECTIONS", debug);
  if (report_collections)
  {
    fprintf(stderr, "[FLX_REPORT_COLLECTIONS] Collection report enabled\n");
  }

  report_gcstats = (bool)egetv("FLX_REPORT_GCSTATS", report_collections);
  if (report_collections)
  {
    fprintf(stderr, "[FLX_REPORT_GCSTATS] GC statistics report enabled\n");
  }


  debug_driver = (bool)egetv("FLX_DEBUG_DRIVER", debug);
  if (debug_driver)
  {
    fprintf(stderr, "[FLX_DEBUG_DRIVER] Driver debug enabled\n");
  }

  finalise = (bool)egetv("FLX_FINALISE", 0);
  if (debug)
    fprintf(stderr,
      "[FLX_FINALISE] Finalisation %s\n", finalise ? "Enabled" : "Disabled");

  // default collection frequency is 1000 interations
  gc_freq = (size_t)egetv("FLX_GC_FREQ", 1000);
  if (gc_freq < 1) gc_freq = 1;
  if (debug)
    fprintf(stderr, "[FLX_GC_FREQ] call gc every %zu iterations\n", gc_freq);

  // default min mem is 10 Meg
  min_mem = (size_t)(egetv("FLX_MIN_MEM", 10) * 1000000.0);
  if (debug)
    fprintf(stderr, "[FLX_MIN_MEM] call gc only if more than %zu Meg heap used\n", min_mem/1000000);

  // default max mem is unlimited
  max_mem = (size_t)(egetv("FLX_MAX_MEM", 0) * 1000000.0);
  if (max_mem == 0) max_mem = (size_t)-1;
  if (debug)
    fprintf(stderr, "[FLX_MAX_MEM] terminate if more than %zu Meg heap used\n", max_mem/1000000);

  // default free factor is 10%, this is also the minimum allowed
  free_factor = egetv("FLX_FREE_FACTOR", 1.1);
  if (free_factor < 1.1) free_factor = 1.1;
  if (debug)
    fprintf(stderr, "[FLX_FREE_FACTOR] reset gc trigger %4.2f times heap used after collection\n", free_factor);

  // experimental flag to allow collection anywhere
  // later, we default this one to true if we can
  // find all the thread stacks, which should be possible
  // with gcc and probably msvc++

  allow_collection_anywhere = (bool)egetv("FLX_ALLOW_COLLECTION_ANYWHERE", 1);
  if (debug)
    fprintf(stderr, "[FLX_ALLOW_COLLECTION_ANYWHERE] %s\n", allow_collection_anywhere ? "True" : "False");

  gcthreads = (int)egetv("FLX_GCTHREADS",0);
  if (debug)
    fprintf(stderr, "[FLX_GCTHREADS] %d\n",gcthreads);

  if (debug) {
    for (int i=0; i<flx_argc; ++i)
      fprintf(stderr, "flx_argv[%d]->%s\n", i, flx_argv[i]);
  }
  return 0;
}