BonoboPersistFile

BonoboPersistFile — Interface for anything that can save / load itself from a file.

Synopsis




                    BonoboPersistFile;
int                 (*BonoboPersistFileIOFn)            (BonoboPersistFile *pf,
                                                         const CORBA_char *uri,
                                                         CORBA_Environment *ev,
                                                         void *closure);
                    BonoboPersistFileClass;
BonoboPersistFile*  bonobo_persist_file_new             (BonoboPersistFileIOFn load_fn,
                                                         BonoboPersistFileIOFn save_fn,
                                                         const gchar *iid,
                                                         void *closure);
BonoboPersistFile*  bonobo_persist_file_construct       (BonoboPersistFile *pf,
                                                         BonoboPersistFileIOFn load_fn,
                                                         BonoboPersistFileIOFn save_fn,
                                                         const gchar *iid,
                                                         void *closure);

Object Hierarchy


  GObject
   +----BonoboObject
         +----BonoboPersist
               +----BonoboPersistFile

Description

The PersistFile interface is a useful interface for Bonoboizing legacy applications, however, for new / correct applications it is far preferable to implement the BonoboPersistStream interface, since this will not only result in a nice clean to your application architecture, but also allow the transparent use of local, remote, and synthetic streams.

This interface works by connecting callbacks to the methods, in a pretty deprecated fashion, it is probably better nowadays to simply sub-class the BonoboXObject and override the epv methods. Either way, after all the caveats here is an example use:

Example 25. Persist file implementation

static gint
load_from_file (BonoboPersistFile *pf,
                const CORBA_char  *filename,
		CORBA_Environment *ev,
                void              *closure)
{
	EogImageData *image_data = closure;

	g_warning ("Load from '%s'", filename);

	return 0; /* Return 0 on success */
}

static gint
save_to_file (BonoboPersistFile *pf,
              const CORBA_char  *filename,
              CORBA_Environment *ev,
              void              *closure)
{
	EogImageData *image_data = closure;

	g_warning ("Save to '%s'", filename);

	return 0; /* Return 0 on success */
}


Having implemented the callbacks we then have to register them and aggregate the interface to our object:

Example 26. Aggregating a new PersistFile

EogImageData *
eog_image_data_construct (EogImageData *image_data)
{
	BonoboObject        *retval;
	BonoboPersistFile   *file;

	file = bonobo_persist_file_new (
		load_from_file, save_to_file, image_data);

	if (file == NULL) {
		bonobo_object_unref (BONOBO_OBJECT (image_data));
		return NULL;
	}

	bonobo_object_add_interface (BONOBO_OBJECT (image_data),
				     BONOBO_OBJECT (file));

	return image_data;
}


Note again, that you should be writing a BonoboPersistStream interface, however if you have already done this you might like to just have hooks through so that old apps can use the PersistFile interface:

Example 27. Chaining to a PersistStream implementation

static gint
load_from_file (BonoboPersistFile *pf,
                const CORBA_char  *filename,
		CORBA_Environment *ev,
                void              *closure)
{
	Bonobo_PersistStream ps = closure;
	BonoboStream *stream;
	
	stream = bonobo_stream_open (
		BONOBO_IO_DRIVER_FS,
		filename, Bonobo_STORAGE_READ,
		0);

	if (!stream)
		return 0;

	.. extract content type from file ...

	Bonobo_PersistStream_load (ps, type, ev);

	return 0; /* Return 0 on success */
}

static gint
save_to_file (BonoboPersistFile *pf,
              const CORBA_char  *filename,
              CORBA_Environment *ev,
              void              *closure)
{
	Bonobo_PersistStream ps = closure;
	BonoboStream *stream;
	
	stream = bonobo_stream_open (
		BONOBO_IO_DRIVER_FS,
		filename, Bonobo_STORAGE_WRITE | Bonobo_STORAGE_CREATE,
		S_IRUSR | S_IWUSR | S_IRGRP);

	if (!stream)
		return 0;

	.. work out content type we want to save ...

	Bonobo_PersistStream_save (ps, type, ev);

	return 0; /* Return 0 on success */
}


The mime type data can be extracted from gnome-vfs or gnome-mime.

Details

BonoboPersistFile

typedef struct _BonoboPersistFile BonoboPersistFile;

Warning

BonoboPersistFile is deprecated and should not be used in newly-written code.

BonoboPersistFileIOFn ()

int                 (*BonoboPersistFileIOFn)            (BonoboPersistFile *pf,
                                                         const CORBA_char *uri,
                                                         CORBA_Environment *ev,
                                                         void *closure);

Warning

BonoboPersistFileIOFn is deprecated and should not be used in newly-written code.

pf :
uri :
ev :
closure :
Returns :

BonoboPersistFileClass

typedef struct {
	BonoboPersistClass parent_class;

	POA_Bonobo_PersistFile__epv epv;

	/* methods */
	int   (*load)             (BonoboPersistFile *ps,
				   const CORBA_char  *uri,
				   CORBA_Environment *ev);

	int   (*save)             (BonoboPersistFile *ps,
				   const CORBA_char  *uri,
				   CORBA_Environment *ev);

	char *(*get_current_file) (BonoboPersistFile *ps,
				   CORBA_Environment *ev);
} BonoboPersistFileClass;

Warning

BonoboPersistFileClass is deprecated and should not be used in newly-written code.

bonobo_persist_file_new ()

BonoboPersistFile*  bonobo_persist_file_new             (BonoboPersistFileIOFn load_fn,
                                                         BonoboPersistFileIOFn save_fn,
                                                         const gchar *iid,
                                                         void *closure);

Warning

bonobo_persist_file_new is deprecated and should not be used in newly-written code.

Creates a BonoboPersistFile object. The load_fn and save_fn parameters might be NULL. If this is the case, the load and save operations are performed by the class load and save methods

load_fn : Loading routine
save_fn : Saving routine
iid : OAF IID of the object this interface is aggregated to
closure : Data passed to IO routines.
Returns : the BonoboPersistFile.

bonobo_persist_file_construct ()

BonoboPersistFile*  bonobo_persist_file_construct       (BonoboPersistFile *pf,
                                                         BonoboPersistFileIOFn load_fn,
                                                         BonoboPersistFileIOFn save_fn,
                                                         const gchar *iid,
                                                         void *closure);

Warning

bonobo_persist_file_construct is deprecated and should not be used in newly-written code.

Initializes the BonoboPersistFile object. The load_fn and save_fn parameters might be NULL. If this is the case, the load and save operations are performed by the class load and save methods

pf : A BonoboPersistFile
load_fn : Loading routine
save_fn : Saving routine
iid : OAF IID of the object this interface is aggregated to
closure : Data passed to IO routines.
Returns : the BonoboPersistFile.

See Also

BonoboPersistStream, BonoboPersist