formats/registry.c

   1 /*
   2  * BabelTrace
   3  *
   4  * Format Registry
   5  *
   6  * Copyright 2010 - Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
   7  *
   8  * Permission is hereby granted, free of charge, to any person obtaining a copy
   9  * of this software and associated documentation files (the "Software"), to deal
  10  * in the Software without restriction, including without limitation the rights
  11  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
  12  * copies of the Software, and to permit persons to whom the Software is
  13  * furnished to do so, subject to the following conditions:
  14  *
  15  * The above copyright notice and this permission notice shall be included in
  16  * all copies or substantial portions of the Software.
  17  */
  18
  19 #include <babeltrace/format.h>
  20 #include <glib.h>
  21 #include <errno.h>
  22
  23 static int init_done;
  24 void __attribute__((constructor)) format_init(void);
  25 void __attribute__((destructor)) format_finalize(void);
  26
  27 /*
  28  * Format registry hash table contains the registered formats. Format
  29  * registration is typically performed by a format plugin.
  30  * TODO: support plugin unload (unregistration of formats).
  31  */
  32 GHashTable *format_registry;
  33
  34 struct format *bt_lookup_format(GQuark qname)
  35 {
  36         if (!init_done)
  37                 return NULL;
  38         return g_hash_table_lookup(format_registry,
  39                                    (gconstpointer) (unsigned long) qname);
  40 }
  41
  42 int bt_register_format(struct format *format)
  43 {
  44         if (!init_done)
  45                 format_init();
  46
  47         if (bt_lookup_format(format->name))
  48                 return -EEXIST;
  49
  50         g_hash_table_insert(format_registry,
  51                             (gpointer) (unsigned long) format->name,
  52                             format);
  53         return 0;
  54 }
  55
  56 void format_init(void)
  57 {
  58         format_registry = g_hash_table_new(g_direct_hash, g_direct_equal);
  59         assert(format_registry);
  60         init_done = 1;
  61 }
  62
  63 void format_finalize(void)
  64 {
  65         g_hash_table_destroy(format_registry);
  66 }