formats/registry.c

   1 /*
   2  * BabelTrace
   3  *
   4  * Format Registry
   5  *
   6  * Copyright (c) 2010 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
   7  *
   8  * This library is free software; you can redistribute it and/or
   9  * modify it under the terms of the GNU Lesser General Public
  10  * License as published by the Free Software Foundation; either
  11  * version 2.1 of the License, or (at your option) any later version.
  12  *
  13  * This library is distributed in the hope that it will be useful,
  14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  16  * Lesser General Public License for more details.
  17  *
  18  * You should have received a copy of the GNU Lesser General Public
  19  * License along with this library; if not, write to the Free Software
  20  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  21  */
  22
  23 #include <glib.h>
  24 #include <errno.h>
  25
  26 static int init_done;
  27 void __attribute__((constructor)) format_init(void);
  28 void __attribute__((destructor)) format_finalize(void);
  29
  30 /*
  31  * Format registry hash table contains the registered formats. Format
  32  * registration is typically performed by a format plugin.
  33  * TODO: support plugin unload (unregistration of formats).
  34  */
  35 GHashTable *format_registry;
  36
  37 struct format *bt_lookup_format(GQuark qname)
  38 {
  39         if (!init_done)
  40                 return NULL;
  41         return g_hash_table_lookup(format_registry,
  42                                    (gconstpointer) (unsigned long) qname)
  43 }
  44
  45 int bt_register_format(const struct format *format)
  46 {
  47         if (!init_done)
  48                 format_init();
  49
  50         if (bt_lookup_format(qname))
  51                 return -EEXIST;
  52
  53         g_hash_table_insert(format_registry,
  54                             (gconstpointer) (unsigned long) format->name,
  55                             format);
  56         return 0;
  57 }
  58
  59 void format_init(void)
  60 {
  61         format_registry = g_hash_table_new(g_direct_hash, g_direct_equal);
  62         assert(format_registry);
  63         init_done = 1;
  64 }
  65
  66 int format_finalize(void)
  67 {
  68         g_hash_table_destroy(format_registry);
  69 }