modify wire plugin load logic to use reference counting

This commit is contained in:
Christian Grothoff 2018-03-12 14:07:42 +01:00
parent 3e191f3b08
commit 7a20062baf
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GPG Key ID: 939E6BE1E29FC3CC

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@ -1,6 +1,6 @@
/*
This file is part of TALER
(C) 2015, 2016, 2017 GNUnet e.V.
(C) 2015, 2016, 2017, 2018 GNUnet e.V.
TALER is free software; you can redistribute it and/or modify it under the
terms of the GNU General Public License as published by the Free Software
@ -23,6 +23,50 @@
#include "taler_util.h"
#include "taler_wire_lib.h"
/**
* A wire plugin that we have loaded.
*/
struct WirePlugin
{
/**
* We keep these in a DLL.
*/
struct WirePlugin *next;
/**
* We keep these in a DLL.
*/
struct WirePlugin *prev;
/**
* Type of this wire plugin.
*/
char *type;
/**
* Wire plugin
*/
struct TALER_WIRE_Plugin *plugin;
/**
* Reference counter for the plugin.
*/
unsigned int rc;
};
/**
* Head of the DLL of loaded wire plugins.
*/
static struct WirePlugin *wp_head;
/**
* Tail of the DLL of loaded wire plugins.
*/
static struct WirePlugin *wp_tail;
/**
* Load a WIRE plugin.
*
@ -36,7 +80,15 @@ TALER_WIRE_plugin_load (const struct GNUNET_CONFIGURATION_Handle *cfg,
{
char *lib_name;
struct TALER_WIRE_Plugin *plugin;
struct WirePlugin *wp;
for (wp = wp_head; NULL != wp; wp = wp->next)
if (0 == strcasecmp (plugin_name,
wp->type))
{
wp->rc++;
return wp->plugin;
}
(void) GNUNET_asprintf (&lib_name,
"libtaler_plugin_wire_%s",
plugin_name);
@ -46,6 +98,15 @@ TALER_WIRE_plugin_load (const struct GNUNET_CONFIGURATION_Handle *cfg,
plugin->library_name = lib_name;
else
GNUNET_free (lib_name);
if (NULL == plugin)
return NULL;
wp = GNUNET_new (struct WirePlugin);
wp->plugin = plugin;
wp->type = GNUNET_strdup (plugin_name);
GNUNET_CONTAINER_DLL_insert (wp_head,
wp_tail,
wp);
wp->rc = 1;
return plugin;
}
@ -58,10 +119,26 @@ TALER_WIRE_plugin_load (const struct GNUNET_CONFIGURATION_Handle *cfg,
void
TALER_WIRE_plugin_unload (struct TALER_WIRE_Plugin *plugin)
{
struct WirePlugin *wp;
char *lib_name;
if (NULL == plugin)
return;
for (wp = wp_head; NULL != wp; wp = wp->next)
{
if (plugin == wp->plugin)
{
wp->rc--;
if (0 < wp->rc)
return;
GNUNET_CONTAINER_DLL_remove (wp_head,
wp_tail,
wp);
GNUNET_free (wp->type);
GNUNET_free (wp);
break;
}
}
lib_name = plugin->library_name;
GNUNET_assert (NULL == GNUNET_PLUGIN_unload (lib_name,
plugin));