Filehandling

* add 'backend' for backend global initialization/destruction
  and common functions.
* WIP: 'file' acts as interface to named files, provides posix
  filehandles with and acquire/release function pair.
* 'filehandle' manages posix filehandles internally, refcounted.
* WIP: 'filehandlecache' keeps unused filehandles in a MRU cache

* WIP: test for filehandle management
* improved filedescriptor test

src/backend/backend.c

@@ -0,0 +1,53 @@
+/*
+  backend  -  common lumiera backend things
+
+  Copyright (C)         Lumiera.org
+    2008,               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.
+*/
+
+#include "backend/backend.h"
+#include "backend/filehandlecache.h"
+#include "backend/filedescriptor.h"
+
+//NOBUG_DEFINE_FLAG_PARENT (backend, lumiera); TODO
+NOBUG_DEFINE_FLAG (backend);
+NOBUG_DEFINE_FLAG_PARENT (file_all, backend);
+
+int
+lumiera_backend_init (void)
+{
+  NOBUG_INIT_FLAG (backend);
+  NOBUG_INIT_FLAG (file_all);
+  NOBUG_INIT_FLAG (file);
+  TRACE (backend);
+  lumiera_filedescriptor_registry_init ();
+
+  int max_entries = 10;         TODO("determine by sysconf (_SC_OPEN_MAX) minus some (big) safety margin "
+                                     "add some override to run tests with few filehandles");
+
+  lumiera_filehandlecache_new (max_entries);
+
+  return 0;
+}
+
+void
+lumiera_backend_destroy (void)
+{
+  TRACE (backend);
+  lumiera_filedescriptor_registry_destroy ();
+  lumiera_filehandlecache_delete ();
+}

src/backend/backend.h

@@ -0,0 +1,36 @@
+/*
+  backend  -  common lumiera backend things
+
+  Copyright (C)         Lumiera.org
+    2008,               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.
+*/
+#ifndef LUMIERA_BACKEND_H
+#define LUMIERA_BACKEND_H
+
+#include <nobug.h>
+
+NOBUG_DECLARE_FLAG (backend);
+NOBUG_DECLARE_FLAG (file_all);
+NOBUG_DECLARE_FLAG (file);
+
+int
+lumiera_backend_init (void);
+
+void
+lumiera_backend_destroy (void);
+
+#endif

src/backend/file.c

@@ -23,17 +23,18 @@
 #include "lib/safeclib.h"
 
 #include "backend/file.h"
+#include "backend/filehandlecache.h"
 #include "backend/filedescriptor.h"
 
 #include <limits.h>
 
-
-NOBUG_DEFINE_FLAG (lumiera_file);
+NOBUG_DEFINE_FLAG_PARENT (file, file_all);
 
 LumieraFile
 lumiera_file_init (LumieraFile self, const char* name, int flags)
 {
-  if (!lumiera_filedescriptor_acquire (&self->descriptor, name, flags))
+  TRACE (file);
+  if (!(self->descriptor = lumiera_filedescriptor_acquire (name, flags)))
     return NULL;
   self->name = lumiera_strndup (name, PATH_MAX);
 
@@ -43,7 +44,8 @@ lumiera_file_init (LumieraFile self, const char* name, int flags)
 LumieraFile
 lumiera_file_destroy (LumieraFile self)
 {
-  lumiera_reference_destroy (&self->descriptor);
+  TRACE (file);
+  lumiera_filedescriptor_release (self->descriptor);
   free ((void*)self->name);
   return self;
 }
@@ -52,6 +54,7 @@ lumiera_file_destroy (LumieraFile self)
 LumieraFile
 lumiera_file_new (const char* name, int flags)
 {
+  TRACE (file);
   LumieraFile self = lumiera_malloc (sizeof (lumiera_file));
   return lumiera_file_init (self, name, flags);
 }
@@ -59,6 +62,48 @@ lumiera_file_new (const char* name, int flags)
 void
 lumiera_file_delete (LumieraFile self)
 {
+  TRACE (file);
   free (lumiera_file_destroy (self));
 }
 
+
+int
+lumiera_file_handle_acquire (LumieraFile self)
+{
+  TRACE (file);
+  REQUIRE (self);
+  REQUIRE (self->descriptor);
+  REQUIRE (fhcache);
+
+  LUMIERA_MUTEX_SECTION (file, self->descriptor->rh, &self->descriptor->lock)
+    {
+      if (!self->descriptor->handle)
+        /* no handle yet, get a new one */
+        lumiera_filehandlecache_handle_acquire (fhcache, self->descriptor);
+      else
+        lumiera_filehandlecache_checkout (fhcache, self->descriptor->handle);
+
+      if (self->descriptor->handle->fd == -1)
+        {
+          TODO ("stat handling/update");
+          self->descriptor->handle->fd = open (self->name, self->descriptor->flags);
+          if (self->descriptor->handle->fd == -1)
+            {
+              LUMIERA_ERROR_SET (file, ERRNO);
+            }
+        }
+    }
+
+  return self->descriptor->handle->fd;
+}
+
+void
+lumiera_file_handle_release (LumieraFile self)
+{
+  TRACE (file);
+
+  LUMIERA_MUTEX_SECTION (file, self->descriptor->rh, &self->descriptor->lock)
+    {
+      lumiera_filehandlecache_checkin (fhcache, self->descriptor->handle);
+    }
+}

src/backend/file.h

@@ -26,7 +26,8 @@
 #include "lib/mutex.h"
 #include "lib/llist.h"
 #include "lib/error.h"
-#include "lib/references.h"
+
+NOBUG_DECLARE_FLAG (file);
 
 /**
  * @file File management
@@ -47,18 +48,18 @@ typedef lumiera_file* LumieraFile;
 #include "backend/filedescriptor.h"
 
 
-
-NOBUG_DECLARE_FLAG (lumiera_file);
-
 #define LUMIERA_FILE_READONLY (O_RDONLY | O_LARGEFILE | O_NOATIME)
 #define LUMIERA_FILE_READWRITE (O_RDWR | O_LARGEFILE | O_NOATIME)
 #define LUMIERA_FILE_CREATE (O_RDWR | O_LARGEFILE | O_NOATIME | O_CREAT | O_EXCL)
 #define LUMIERA_FILE_RECREATE (O_RDWR | O_LARGEFILE | O_NOATIME | O_CREAT | O_TRUNC)
 
+/* creat and excl flags will be masked out for descriptor lookup */
+#define LUMIERA_FILE_MASK ~(O_CREAT | O_EXCL)
+
 struct lumiera_file_struct
 {
   const char* name;
-  struct lumiera_reference_struct descriptor;
+  LumieraFiledescriptor descriptor;
 };
 
 /**
@@ -86,5 +87,11 @@ void
 lumiera_file_delete (LumieraFile self);
 
 
+int
+lumiera_file_handle_acquire (LumieraFile self);
+
+void
+lumiera_file_handle_release (LumieraFile self);
+
 #endif
 

src/backend/filedescriptor.c

@@ -23,7 +23,10 @@
 #include "lib/safeclib.h"
 #include "lib/cuckoo.h"
 
+#include "backend/file.h"
 #include "backend/filedescriptor.h"
+#include "backend/filehandle.h"
+#include "backend/filehandlecache.h"
 
 #include <sys/types.h>
 #include <fcntl.h>
@@ -141,6 +144,7 @@ lumiera_filedescriptor_acquire (const char* name, int flags)
                 }
 
               int fd;
+              INFO (filedescriptor, "try creating file: %s", name);
               fd = creat (name, 0777);
               if (fd == -1)
                 {

src/backend/filehandle.c

@@ -0,0 +1,70 @@
+/*
+  filehandle  -  filehandle management and caching
+
+  Copyright (C)         Lumiera.org
+    2008,               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.
+*/
+
+#include "lib/llist.h"
+#include "lib/safeclib.h"
+
+#include "backend/file.h"
+#include "backend/filehandle.h"
+#include "backend/filedescriptor.h"
+
+#include <unistd.h>
+
+NOBUG_DEFINE_FLAG_PARENT (filehandle, file_all);
+
+LumieraFilehandle
+lumiera_filehandle_new ()
+{
+  LumieraFilehandle self = lumiera_malloc (sizeof (lumiera_filehandle));
+  TRACE (filehandle, "%p", self);
+
+  llist_init (&self->cachenode);
+  self->fd = -1;
+  self->use_cnt = 1;
+  self->descriptor = NULL;
+
+  return self;
+}
+
+
+void*
+lumiera_filehandle_destroy_node (LList node)
+{
+  TRACE (filehandle);
+  REQUIRE (llist_is_empty (node));
+  LumieraFilehandle self = (LumieraFilehandle)node;
+  REQUIRE (self->use_cnt == 0);
+
+  if (self->fd >= 0)
+    close (self->fd);
+  self->fd = -1;
+  self->descriptor = NULL;
+  return self;
+}
+
+
+int
+lumiera_filehandle_get (LumieraFilehandle self)
+{
+  REQUIRE (self->descriptor);
+  return -1;
+}
+

src/backend/filehandle.h

@@ -24,6 +24,11 @@
 #include "lib/error.h"
 #include "lib/llist.h"
 
+typedef struct lumiera_filehandle_struct lumiera_filehandle;
+typedef lumiera_filehandle* LumieraFilehandle;
+
+#include "backend/filedescriptor.h"
+
 /**
  * @file Filehandles
  */
@@ -35,16 +40,17 @@
 struct lumiera_filehandle_struct
 {
   llist cachenode;
-  int handle;
-  //LumieraFile file;
-  //lumiera_mutex lock;
+  int fd;
+  unsigned use_cnt;
+  LumieraFiledescriptor descriptor;
 };
-typedef struct lumiera_filehandle_struct lumiera_filehandle;
-typedef lumiera_filehandle* LumieraFilehandle;
 
 LumieraFilehandle
 lumiera_filehandle_new ();
 
+int
+lumiera_filehandle_get (LumieraFilehandle self);
+
 void*
 lumiera_filehandle_destroy_node (LList node);
 

src/backend/filehandlecache.c

@@ -19,41 +19,60 @@
   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 */
 
+#include "lib/safeclib.h"
+
+#include "backend/file.h"
 #include "backend/filehandlecache.h"
 
-NOBUG_DEFINE_FLAG (lumiera_filehandlecache);
+NOBUG_DEFINE_FLAG_PARENT (filehandlecache, file_all);
 
 /* errors */
 
 LUMIERA_ERROR_DEFINE (FILEHANDLECACHE_NOHANDLE, "No filehandle available");
 
 
-/**/
+LumieraFilehandlecache fhcache = NULL;
 
-LumieraFilehandlecache
-lumiera_filehandlecache_init (LumieraFilehandlecache self, int max_entries)
+
+void
+lumiera_filehandlecache_new (int max_entries)
 {
-  lumiera_mrucache_init (&self->cache, lumiera_filehandle_destroy_node);
-  self->available =max_entries;
-  lumiera_mutex_init (&self->lock);
-  return self;
+  if (!fhcache)
+    {
+      NOBUG_INIT_FLAG (filehandlecache);
+      fhcache = lumiera_malloc (sizeof (lumiera_filehandlecache));
+      lumiera_mrucache_init (&fhcache->cache, lumiera_filehandle_destroy_node);
+      fhcache->available = max_entries;
+      fhcache->checked_out = 0;
+      lumiera_mutex_init (&fhcache->lock);
+      RESOURCE_ANNOUNCE (filehandlecache, "mutex", "filehandlecache", fhcache, fhcache->rh);
+    }
+  else
+    NOTREACHED;
 }
 
-LumieraFilehandlecache
-lumiera_filehandlecache_destroy (LumieraFilehandlecache self)
+
+void
+lumiera_filehandlecache_delete (void)
 {
-  self->available += self->cache.cached;
-  lumiera_mrucache_destroy (&self->cache);
-  lumiera_mutex_destroy (&self->lock);
-  return self;
+  if (fhcache)
+    {
+      REQUIRE (!fhcache->checked_out, "Filehandles in use at shutdown");
+      RESOURCE_FORGET (filehandlecache, fhcache->rh);
+      lumiera_mrucache_destroy (&fhcache->cache);
+      lumiera_mutex_destroy (&fhcache->lock);
+      free (fhcache);
+      fhcache = NULL;
+    }
 }
 
 
 LumieraFilehandle
-lumiera_filehandlecache_filehandle_acquire (LumieraFilehandlecache self)
+lumiera_filehandlecache_handle_acquire (LumieraFilehandlecache self, LumieraFiledescriptor desc)
 {
-  LumieraFilehandle ret;
-  LUMIERA_MUTEX_SECTION (&self->lock)
+  TRACE (filehandlecache);
+  LumieraFilehandle ret = NULL;
+  LUMIERA_MUTEX_SECTION (filehandlecache, self->rh, &self->lock)
   {
     if (self->available <= 0 && self->cache.cached)
       {
@@ -65,19 +84,58 @@ lumiera_filehandlecache_filehandle_acquire (LumieraFilehandlecache self)
       }
     else
       {
-        /* allocate new filehandle if we are below the limit or no cached handles where available (overallocating) */
+        /* allocate new filehandle if we are below the limit or no cached handles are available (overallocating) */
         ret = lumiera_filehandle_new ();
         if (!ret)
-          LUMIERA_ERROR_SET (lumiera_filehandlecache, FILEHANDLECACHE_NOHANDLE);
+          LUMIERA_ERROR_SET (filehandlecache, FILEHANDLECACHE_NOHANDLE);
         else
           --self->available;
       }
+    ret->use_cnt = 1;
+    ret->descriptor = desc;
+    desc->handle = ret;
+    ++self->checked_out;
   }
   return ret;
 }
 
-void
-lumiera_filehandlecache_add (LumieraFilehandlecache self, LumieraFilehandle handle)
+
+LumieraFilehandle
+lumiera_filehandlecache_checkout (LumieraFilehandlecache self, LumieraFilehandle handle)
 {
-  UNIMPLEMENTED ("");
+  REQUIRE (self);
+  REQUIRE (handle);
+  /* This function is called with the associated descriptor locked, nothing can modify 'handle' */
+  if (!handle->use_cnt)
+    {
+      /* lock cache and checkout */
+      LUMIERA_MUTEX_SECTION (filehandlecache, self->rh, &self->lock)
+        {
+          lumiera_mrucache_checkout (&self->cache, &handle->cachenode);
+        }
+    }
+  ++handle->use_cnt;
+  ++self->checked_out;
+
+  return handle;
 }
+
+void
+lumiera_filehandlecache_checkin (LumieraFilehandlecache self, LumieraFilehandle handle)
+{
+  REQUIRE (self);
+  REQUIRE (handle);
+  REQUIRE (handle->use_cnt);
+
+  /* This function is called with the associated descriptor locked, nothing can modify 'self' */
+  if (!--handle->use_cnt)
+    {
+      /* lock cache and checin */
+      LUMIERA_MUTEX_SECTION (filehandlecache, self->rh, &self->lock)
+        {
+          --self->checked_out;
+          lumiera_mrucache_checkin (&self->cache, &handle->cachenode);
+        }
+    }
+}
+

src/backend/filehandlecache.h

@@ -25,6 +25,9 @@
 #include "lib/mrucache.h"
 #include "lib/mutex.h"
 
+typedef struct lumiera_filehandlecache_struct lumiera_filehandlecache;
+typedef lumiera_filehandlecache* LumieraFilehandlecache;
+
 #include "backend/filehandle.h"
 
 /**
@@ -43,55 +46,55 @@ struct lumiera_filehandlecache_struct
 {
   lumiera_mrucache cache;
   int available;
+  int checked_out;
   lumiera_mutex lock;
+  RESOURCE_HANDLE (rh);
 };
-typedef struct lumiera_filehandlecache_struct lumiera_filehandlecache;
-typedef lumiera_filehandlecache* LumieraFilehandlecache;
 
+extern LumieraFilehandlecache fhcache;
 
 /**
- * Initializes a filehandle cache.
- * @param self pointer to the cache to be initialized
+ * Initializes the filehandle cache.
  * @param max_entries number how much filehandles shall be managed
- * @return self as given
  * The number of elements the cache can hold is static and should be
- * determined by sysconf (_SC_OPEN_MAX) minus some safety margin.
+ * determined by sysconf (_SC_OPEN_MAX) minus some (big) safety margin.
  */
-LumieraFilehandlecache
-lumiera_filehandlecache_init (LumieraFilehandlecache self, int max_entries);
+void
+lumiera_filehandlecache_new (int max_entries);
 
 /**
- * Destroy a filehandle cache.
- * @param self the cache to be destroyed
- * @return self as given to the now uninitialized! cache
+ * Delete the filehandle cache.
  * No filehandles in the cache must be locked, this would be a fatal error.
  * The handles are closed automatically.
  */
-LumieraFilehandlecache
-lumiera_filehandlecache_destroy (LumieraFilehandlecache self);
+void
+lumiera_filehandlecache_delete (void);
 
 /**
  * Get a fresh filehandle.
  * @param self pointer to the cache
  * @return the new filehandle
- * one must call lumiera_mutexacquirer_unlock (&lock) to free the lock on the handle when done
  */
 LumieraFilehandle
-lumiera_filehandlecache_filehandle_acquire (LumieraFilehandlecache self);
+lumiera_filehandlecache_handle_acquire (LumieraFilehandlecache self, LumieraFiledescriptor desc);
 
 /**
- * Add filehande back to cache.
+ * Add filehande back to cache, the filehandle becomes subject of aging.
  * @param self pointer to the cache
  * @param handle filehandle to be put back
  */
 void
-lumiera_filehandlecache_add (LumieraFilehandlecache self, LumieraFilehandle handle);
+lumiera_filehandlecache_add_filehandle (LumieraFilehandlecache self, LumieraFilehandle handle);
 
 /**
- * 
+ * Remove a filehandle from cache aging
+ * Filehandles which are subject of cache aging must be checked out before they can be used
+ *
  */
 LumieraFilehandle
-lumiera_filehandlecache_remove (LumieraFilehandlecache self, int fd);
+lumiera_filehandlecache_checkout (LumieraFilehandlecache self, LumieraFilehandle handle);
 
+void
+lumiera_filehandlecache_checkin (LumieraFilehandlecache self, LumieraFilehandle handle);
 
 #endif

tests/20filehandle.tests

@@ -0,0 +1,7 @@
+
+TESTING "Filehandle management" ./test-filehandles
+
+
+TEST "basic filehandle usage" basic <<END
+return: 0
+END

tests/Makefile.am

@@ -56,9 +56,9 @@ test_filedescriptors_SOURCES = $(tests_srcdir)/backend/test-filedescriptors.c
 test_filedescriptors_CPPFLAGS = $(AM_CPPFLAGS) -std=gnu99 -Wall -Werror -I$(top_srcdir)/src/
 test_filedescriptors_LDADD = liblumibackend.a liblumi.a -lnobugmt -lpthread -ldl -lm
 
-#check_PROGRAMS += test-filehandles
-#test_filehandles_SOURCES = $(tests_srcdir)/backend/test-filehandles.c
-#test_filehandles_CPPFLAGS = $(AM_CPPFLAGS) -std=gnu99 -Wall -Werror -I$(top_srcdir)/src/
-#test_filehandles_LDADD = liblumibackend.a liblumi.a -lnobugmt -lpthread -ldl -lm
+check_PROGRAMS += test-filehandles
+test_filehandles_SOURCES = $(tests_srcdir)/backend/test-filehandles.c
+test_filehandles_CPPFLAGS = $(AM_CPPFLAGS) -std=gnu99 -Wall -Werror -I$(top_srcdir)/src/
+test_filehandles_LDADD = liblumibackend.a liblumi.a -lnobugmt -lpthread -ldl -lm
 
 TESTS = $(tests_srcdir)/test.sh

tests/backend/test-filedescriptors.c

@@ -22,19 +22,21 @@
 
 #include "lib/safeclib.h"
 
+#include "backend/backend.h"
 #include "backend/filedescriptor.h"
 
 #include "tests/test.h"
 
 TESTS_BEGIN
 
-
 TEST ("acquire_existing")
 {
+  lumiera_backend_init ();
   LumieraFiledescriptor descriptor = lumiera_filedescriptor_acquire (",tmp_testfile", LUMIERA_FILE_READONLY);
   if (descriptor)
     {
       lumiera_filedescriptor_release (descriptor);
+      lumiera_backend_destroy ();
       return 0;
     }
   else
@@ -43,12 +45,14 @@ TEST ("acquire_existing")
 
 TEST ("acquire_existing_again")
 {
+  lumiera_backend_init ();
   LumieraFiledescriptor descriptor = lumiera_filedescriptor_acquire (",tmp_testfile", LUMIERA_FILE_READONLY);
   if (descriptor)
     {
       LumieraFiledescriptor descriptor2 = lumiera_filedescriptor_acquire (",tmp_testfile", LUMIERA_FILE_READONLY);
       lumiera_filedescriptor_release (descriptor2);
       lumiera_filedescriptor_release (descriptor);
+      lumiera_backend_destroy ();
       return 0;
     }
   else
@@ -57,10 +61,12 @@ TEST ("acquire_existing_again")
 
 TEST ("acquire_create")
 {
+  lumiera_backend_init ();
   LumieraFiledescriptor descriptor = lumiera_filedescriptor_acquire (",tmp_testfile", LUMIERA_FILE_CREATE);
   if (descriptor)
     {
       lumiera_filedescriptor_release (descriptor);
+      lumiera_backend_destroy ();
       return 0;
     }
   else
@@ -69,11 +75,13 @@ TEST ("acquire_create")
 
 TEST ("acquire_create_dir")
 {
+  lumiera_backend_init ();
   LumieraFiledescriptor descriptor =
     lumiera_filedescriptor_acquire (",tmp_testdir/nested/,tmp_testfile", LUMIERA_FILE_CREATE);
   if (descriptor)
     {
       lumiera_filedescriptor_release (descriptor);
+      lumiera_backend_destroy ();
       return 0;
     }
   else

tests/backend/test-filehandles.c

@@ -0,0 +1,58 @@
+/*
+  test-filehandles.c  -  test filehandle management
+
+  Copyright (C)         Lumiera.org
+    2008,               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.
+*/
+#define _GNU_SOURCE
+
+#include "lib/llist.h"
+
+#include "backend/backend.h"
+#include "backend/filehandlecache.h"
+
+#include "tests/test.h"
+
+TESTS_BEGIN
+
+TEST ("basic")
+{
+  lumiera_backend_init ();
+  LumieraFile file = lumiera_file_new (",tmp_testfile", LUMIERA_FILE_CREATE);
+
+  /* get the filehandle */
+  int fd = lumiera_file_handle_acquire (file);
+
+  /* we now 'own'it and can use it */
+  ENSURE (fd > -1);
+  printf ("got filehandle #%d\n", fd);
+
+  /* put it into aging, can't use anymore */
+  lumiera_file_handle_release (file);
+
+  lumiera_file_delete (file);
+  lumiera_backend_destroy ();
+}
+
+
+TEST ("more")
+{
+  lumiera_backend_init ();
+  lumiera_backend_destroy ();
+}
+
+TESTS_END