src/util/speedup.c

   1 /*
   2      This file is part of GNUnet.
   3      Copyright (C) 2011-2013 GNUnet e.V.
   4
   5      GNUnet is free software; you can redistribute it and/or modify
   6      it under the terms of the GNU General Public License as published
   7      by the Free Software Foundation; either version 3, or (at your
   8      option) any later version.
   9
  10      GNUnet is distributed in the hope that it will be useful, but
  11      WITHOUT ANY WARRANTY; without even the implied warranty of
  12      MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13      General Public License for more details.
  14
  15      You should have received a copy of the GNU General Public License
  16      along with GNUnet; see the file COPYING.  If not, write to the
  17      Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
  18      Boston, MA 02110-1301, USA.
  19 */
  20
  21 /**
  22  * @file util/speedup.c
  23  * @author Matthias Wachs
  24  * @brief functions to speedup peer execution by manipulation system time
  25  */
  26 #include "platform.h"
  27 #include "gnunet_util_lib.h"
  28 #include "speedup.h"
  29
  30 #define LOG(kind,...) GNUNET_log_from (kind, "util-speedup", __VA_ARGS__)
  31
  32
  33 static struct GNUNET_TIME_Relative interval;
  34
  35 static struct GNUNET_TIME_Relative delta;
  36
  37 static struct GNUNET_SCHEDULER_Task *speedup_task;
  38
  39
  40 static void
  41 do_speedup (void *cls)
  42 {
  43   static long long current_offset;
  44
  45   speedup_task = NULL;
  46   current_offset += delta.rel_value_us;
  47   GNUNET_TIME_set_offset (current_offset);
  48   LOG (GNUNET_ERROR_TYPE_DEBUG,
  49        "Speeding up execution time by %s\n",
  50        GNUNET_STRINGS_relative_time_to_string (delta, GNUNET_NO));
  51   speedup_task = GNUNET_SCHEDULER_add_delayed (interval,
  52                                                &do_speedup,
  53                                                NULL);
  54 }
  55
  56
  57 /**
  58  * Start task that may speed up our system clock artificially
  59  *
  60  * @param cfg configuration to use
  61  * @return #GNUNET_OK on success, #GNUNET_SYSERR if the speedup was not configured
  62  */
  63 int
  64 GNUNET_SPEEDUP_start_ (const struct GNUNET_CONFIGURATION_Handle *cfg)
  65 {
  66   GNUNET_assert (NULL == speedup_task);
  67   if (GNUNET_OK !=
  68       GNUNET_CONFIGURATION_get_value_time (cfg,
  69                                            "testing",
  70                                            "SPEEDUP_INTERVAL",
  71                                            &interval))
  72     return GNUNET_SYSERR;
  73   if (GNUNET_OK !=
  74       GNUNET_CONFIGURATION_get_value_time (cfg,
  75                                            "testing",
  76                                            "SPEEDUP_DELTA",
  77                                            &delta))
  78     return GNUNET_SYSERR;
  79
  80   if ( (0 == interval.rel_value_us) ||
  81        (0 == delta.rel_value_us) )
  82   {
  83     LOG (GNUNET_ERROR_TYPE_DEBUG,
  84          "Speed up disabled\n");
  85     return GNUNET_OK;
  86   }
  87   LOG (GNUNET_ERROR_TYPE_DEBUG,
  88        "Speed up execution by %s\n",
  89        GNUNET_STRINGS_relative_time_to_string (delta, GNUNET_NO));
  90   LOG (GNUNET_ERROR_TYPE_DEBUG,
  91        "Speed up executed every %s\n",
  92        GNUNET_STRINGS_relative_time_to_string (interval, GNUNET_NO));
  93   speedup_task = GNUNET_SCHEDULER_add_now_with_lifeness (GNUNET_NO,
  94                                                          &do_speedup,
  95                                                          NULL);
  96   return GNUNET_OK;
  97 }
  98
  99
 100 /**
 101  * Stop tasks that modify clock behavior.
 102  */
 103 void
 104 GNUNET_SPEEDUP_stop_ ()
 105 {
 106   if (NULL != speedup_task)
 107   {
 108     GNUNET_SCHEDULER_cancel (speedup_task);
 109     speedup_task = NULL;
 110   }
 111   if ( (0 != interval.rel_value_us) &&
 112        (0 != delta.rel_value_us) )
 113     LOG (GNUNET_ERROR_TYPE_DEBUG,
 114          "Stopped execution speed up\n");
 115 }
 116
 117 /* end of speedup.c */