src/cache.h

   1 /* vim:tw=78:ts=8:sw=4:set ft=c:  */
   2 /*
   3     Copyright (C) 2006-2008 Ben Kibbey <bjk@luxsci.net>
   4
   5     This program is free software; you can redistribute it and/or modify
   6     it under the terms of the GNU General Public License as published by
   7     the Free Software Foundation; either version 2 of the License, or
   8     (at your option) any later version.
   9
  10     This program is distributed in the hope that it will be useful,
  11     but WITHOUT ANY WARRANTY; without even the implied warranty of
  12     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13     GNU General Public License for more details.
  14
  15     You should have received a copy of the GNU General Public License
  16     along with this program; if not, write to the Free Software
  17     Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  18 */
  19 #ifndef CACHE_H
  20 #define CACHE_H
  21
  22 #include <pth.h>
  23
  24 #ifdef DEBUG
  25 #define CACHE_LOCK_DEBUG        log_write(N_("LOCK %s tid=%p"), __FUNCTION__, pth_self());
  26 #define CACHE_UNLOCK_DEBUG      log_write(N_("UNLOCK %s tid=%p"), __FUNCTION__, pth_self());
  27 #else
  28 #define CACHE_LOCK_DEBUG
  29 #define CACHE_UNLOCK_DEBUG
  30 #endif
  31
  32 #define CACHE_TRYLOCK(ctx)      if (pth_mutex_acquire(&cache_mutex, TRUE, NULL) == FALSE) {\
  33                                     if (errno == EBUSY) { \
  34                                         log_write(N_("%s(): cache mutex LOCKED"), __FUNCTION__); \
  35                                         if (ctx) \
  36                                             assuan_write_status(ctx, "LOCKED", N_("Waiting for lock")); \
  37                                         pth_mutex_acquire(&cache_mutex, FALSE, NULL); \
  38                                     } \
  39                                     else \
  40                                         log_write("%s(%i): %s", __FUNCTION__, __LINE__, strerror(errno)); \
  41                                 }
  42
  43 #define CACHE_LOCK(ctx)         CACHE_LOCK_DEBUG CACHE_TRYLOCK(ctx)
  44 #define CACHE_UNLOCK            CACHE_UNLOCK_DEBUG pth_mutex_release(&cache_mutex)
  45
  46 typedef struct {
  47     guchar filename[16];        /* MD5 hash. */
  48     guchar key[32];             /* SHA256/AES256/gcrykeysize */
  49     gboolean used;              /* If this cache slot is used. */
  50     glong timeout;              /* adjust_cache_time_thread(). */
  51     glong reset;                /* To reset .timeout. */
  52     pth_mutex_t *mutex;         /* Not related to cache_mutex. */
  53     gint refcount;              /* The number of associated clients. */
  54 } file_cache_t;
  55
  56 void *key_cache;
  57 glong cache_size;
  58 pth_mutex_t cache_mutex;
  59
  60 void cache_adjust_timer(void);
  61 gboolean cache_set_timeout(const guchar *md5filename, glong timeout);
  62 gboolean cache_reset_timeout(const guchar *md5filename, glong timeout);
  63 gboolean cache_iscached(const guchar *md5filename);
  64 gboolean cache_clear(const guchar *md5filename, gint which);
  65 gboolean cache_add_file(const guchar *md5file, const guchar *shakey);
  66 gboolean cache_get_key(const guchar *md5file, guchar *shakey);
  67 gboolean cache_update_key(const guchar *md5filename, const guchar *shakey);
  68 gint cache_file_count(void);
  69 gboolean cache_has_file(const guchar *md5file);
  70 void send_cache_status_all(void);
  71 gboolean cache_get_mutex(const guchar *md5filename, pth_mutex_t **result);
  72 gboolean cache_decr_refcount(const guchar *md5filename);
  73 gboolean cache_incr_refcount(const guchar *md5filename);
  74
  75 #endif