src/mutex.h

   1 /* vim:tw=78:ts=8:sw=4:set ft=c:  */
   2 /*
   3     Copyright (C) 2006, 2007, 2008, 2009, 2010, 2011, 2012
   4     Ben Kibbey <bjk@luxsci.net>
   5
   6     This program is free software; you can redistribute it and/or modify
   7     it under the terms of the GNU General Public License as published by
   8     the Free Software Foundation; either version 2 of the License, or
   9     (at your option) any later version.
  10
  11     This program is distributed in the hope that it will be useful,
  12     but WITHOUT ANY WARRANTY; without even the implied warranty of
  13     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14     GNU General Public License for more details.
  15
  16     You should have received a copy of the GNU General Public License
  17     along with this program; if not, write to the Free Software
  18     Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02110-1301  USA
  19 */
  20 #ifndef LOCK_H
  21 #define LOCK_H
  22
  23 #include <pth.h>
  24 #include <assert.h>
  25 #include <errno.h>
  26 #include "cache.h"
  27
  28 #ifdef MUTEX_DEBUG
  29 #define MUTEX_LOCK_DEBUG(m) \
  30     log_write("%s(%i): %s(): LOCK %p", __FILE__, __LINE__, __FUNCTION__, m);
  31 #define MUTEX_UNLOCK_DEBUG(m) \
  32     log_write("%s(%i): %s(): UNLOCK %p", __FILE__, __LINE__, __FUNCTION__, m);
  33 #else
  34 #define MUTEX_LOCK_DEBUG(m)
  35 #define MUTEX_UNLOCK_DEBUG(m)
  36 #endif
  37
  38 #define CACHE_LOCK(ctx) MUTEX_LOCK(&cache_mutex)
  39 #define CACHE_UNLOCK MUTEX_UNLOCK(&cache_mutex)
  40
  41 #define MUTEX_LOCK(m) \
  42     MUTEX_LOCK_DEBUG(m) \
  43     if (!pth_mutex_acquire(m, FALSE, NULL)) { \
  44         log_write("%s(%i): %s: LOCK", __FILE__, __LINE__, strerror(errno)); \
  45         assert(0); \
  46     } \
  47
  48 #define MUTEX_UNLOCK(m) \
  49     MUTEX_UNLOCK_DEBUG(m) \
  50     if (!pth_mutex_release(m) && errno != EDEADLK) { \
  51         log_write("%s(%i): %s: UNLOCK", __FILE__, __LINE__, strerror(errno)); \
  52         assert(0); \
  53     }
  54
  55 #define MUTEX_LOCK_EV(client, m, rc) { \
  56     pth_event_t ev = pth_event(PTH_EVENT_FD|PTH_UNTIL_FD_READABLE, \
  57             client->thd->fd); \
  58     MUTEX_LOCK_DEBUG(m) \
  59     if (!pth_mutex_acquire(m, FALSE, ev)) { \
  60         rc = gpg_error_from_errno(errno); \
  61         log_write("%s(%i): LOCK: %s", __FILE__, __LINE__, pwmd_strerror(rc));\
  62     } \
  63     pth_event_free(ev, PTH_FREE_ALL); \
  64 }
  65
  66 #define MUTEX_TRYLOCK(client, m, rc) \
  67     if (!pth_mutex_acquire(m, TRUE, NULL)) { \
  68         if (errno == EBUSY) { \
  69             if (client && client->ctx) {\
  70                 rc = send_status(client->ctx, STATUS_LOCKED, NULL); \
  71                 if (!rc) { \
  72                     MUTEX_LOCK_EV(client, m, rc); \
  73                 } \
  74             } \
  75         } \
  76         else { \
  77             log_write("%s(%i): %s: LOCK errno=%i", __FILE__, __LINE__, __FUNCTION__, errno); \
  78             assert(0); \
  79         } \
  80     } \
  81     else { \
  82         MUTEX_LOCK_DEBUG(m) \
  83     }
  84
  85 #endif