lumiera_/src/vault/filedescriptorregistry.c

152 lines
3.8 KiB
C

/*
FiledescriptorRegistry - registry for tracking all files in use
Copyright (C) Lumiera.org
2008, 2010, Christian Thaeter <ct@pipapo.org>
This program 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 Foundation; either version 2 of
the License, or (at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
* *****************************************************/
/** @file filedescriptorregistry.c
** Implementation of a registry to manage used filedescriptors
** @todo development in this area is stalled since 2010
*/
#include "include/logging.h"
#include "lib/safeclib.h"
#include "lib/mutex.h"
#include "lib/psplay.h"
#include "vault/file.h"
#include "vault/filedescriptor.h"
#include "vault/filedescriptorregistry.h"
/**
* the global registry for file descriptors.
*/
static PSplay filedescriptorregistry = NULL;
static lumiera_mutex filedescriptorregistry_mutex;
static int
cmp_fn (const void* keya, const void* keyb)
{
const LumieraFiledescriptor a = (const LumieraFiledescriptor)keya;
const LumieraFiledescriptor b = (const LumieraFiledescriptor)keyb;
if (a->stat.st_dev < b->stat.st_dev)
return -1;
else if (a->stat.st_dev > b->stat.st_dev)
return 1;
if (a->stat.st_ino < b->stat.st_ino)
return -1;
else if (a->stat.st_ino > b->stat.st_ino)
return 1;
if ((a->flags&LUMIERA_FILE_MASK) < (b->flags&LUMIERA_FILE_MASK))
return -1;
else if ((a->flags&LUMIERA_FILE_MASK) > (b->flags&LUMIERA_FILE_MASK))
return 1;
return 0;
}
static void
delete_fn (PSplaynode node)
{
TODO ("figure name out? or is the handle here always closed");
lumiera_filedescriptor_delete ((LumieraFiledescriptor) node, NULL);
}
static const void*
key_fn (const PSplaynode node)
{
return node;
}
void
lumiera_filedescriptorregistry_init (void)
{
TRACE (filedescriptor_dbg);
REQUIRE (!filedescriptorregistry);
filedescriptorregistry = psplay_new (cmp_fn, key_fn, delete_fn);
if (!filedescriptorregistry)
LUMIERA_DIE (NO_MEMORY);
lumiera_mutex_init (&filedescriptorregistry_mutex, "filedescriptorregistry", &NOBUG_FLAG (mutex_dbg), NOBUG_CONTEXT);
}
void
lumiera_filedescriptorregistry_destroy (void)
{
TRACE (filedescriptor_dbg);
REQUIRE (!psplay_nelements (filedescriptorregistry));
lumiera_mutex_destroy (&filedescriptorregistry_mutex, &NOBUG_FLAG (mutex_dbg), NOBUG_CONTEXT);
if (filedescriptorregistry)
psplay_delete (filedescriptorregistry);
filedescriptorregistry = NULL;
}
LumieraFiledescriptor
lumiera_filedescriptorregistry_ensure (LumieraFiledescriptor template)
{
REQUIRE (filedescriptorregistry, "not initialised");
LumieraFiledescriptor ret = NULL;
LUMIERA_MUTEX_SECTION (mutex_sync, &filedescriptorregistry_mutex)
{
/* lookup/create descriptor */
ret = (LumieraFiledescriptor) psplay_find (filedescriptorregistry, template, 100);
if (!ret)
{
ret = lumiera_filedescriptor_new (template);
if (!ret)
goto error;
psplay_insert (filedescriptorregistry, &ret->node, 100);
}
error:
;
}
return ret;
}
void
lumiera_filedescriptorregistry_remove (LumieraFiledescriptor self)
{
LUMIERA_MUTEX_SECTION (mutex_sync, &filedescriptorregistry_mutex)
psplay_remove (filedescriptorregistry, &self->node);
}