#include <stdio.h>
#include <stdarg.h>
#include <stdlib.h>

int dodebug = 0, dbug_level = 0, OnlyLevel = 0;
int first = 1;

int DoDebug(int level)
{
   char *DebugLevel;
   if (first) {
      if ((DebugLevel = getenv("DEBUG_LEVEL"))) {
         dodebug = 1;
         dbug_level = atoi(DebugLevel);

         if (dbug_level < 0) {
            dbug_level = -dbug_level;
            OnlyLevel = 1;
         }
      }
      first = 0;
   }

   if (!dodebug)
      return 0;

   if (OnlyLevel && level != dbug_level) return 0;

   if (level > dbug_level) return 0;
   
   return 1;
}

void debug(int level, char *fmt, ...)
{
   va_list args;
   char *DebugLevel, msg[128];
   short NoHdr = 0;

   if (first) {
      if ((DebugLevel = getenv("DEBUG_LEVEL"))) {
         dodebug = 1;
         dbug_level = atoi(DebugLevel);

         if (dbug_level < 0) {
            dbug_level = -dbug_level;
            OnlyLevel = 1;
         }
      }
      first = 0;
   }

   if (!dodebug)
      return;

   if (OnlyLevel && level != dbug_level) return;
     
   if (level < 0) {
      level = -level;
      NoHdr = 1;
   }

   if (level > dbug_level) return;

   va_start(args, fmt);

   if (NoHdr)
      (void)vfprintf(stderr, fmt, args);
   else
   {
      (void)vsprintf(msg, fmt, args);
      (void)fprintf(stderr, "dbug %d: %s", level, msg);
   }
   fflush(stderr);

   va_end(args);

}