TeplMetadataManager: libgedit-tepl 6 Reference Manual

TeplMetadataManager

TeplMetadataManager — To store file metadata on disk

Functions

TeplMetadataManager *	tepl_metadata_manager_get_singleton ()
void	tepl_metadata_manager_trim ()
gboolean	tepl_metadata_manager_load_from_disk ()
gboolean	tepl_metadata_manager_save_to_disk ()
void	tepl_metadata_manager_copy_from ()
void	tepl_metadata_manager_merge_into ()

Types and Values

struct

TeplMetadataManager

Object Hierarchy

    GObject
    ╰── TeplMetadataManager

Includes

#include <tepl/tepl.h>

Description

TeplMetadataManager permits to store file metadata on disk. It serves both as an easier replacement for GVfs metadata, and to have metadata support on platforms that don't support GVfs metadata.

For the GFile where the metadata are stored (see the tepl_metadata_manager_load_from_disk() and tepl_metadata_manager_save_to_disk() functions), the following applies:

A good place to store the metadata is in a sub-directory of the user data directory. See g_get_user_data_dir().
The GFile must be different for each process. It is advised for your application to rely on GApplication process uniqueness. TeplMetadataManager doesn't support concurrent accesses to the same GFile from different processes. Which means that metadata cannot be shared between applications.

High-level API

TeplMetadataManager and TeplMetadata are integrated in the Tepl framework, see:

tepl_application_handle_metadata().
the metadata API of TeplBuffer.

Functions

tepl_metadata_manager_get_singleton ()

TeplMetadataManager *
tepl_metadata_manager_get_singleton (void);

Returns

the TeplMetadataManager singleton instance.

[transfer none]

Since: 5.0

tepl_metadata_manager_trim ()

void
tepl_metadata_manager_trim (TeplMetadataManager *manager,
                            gint max_number_of_locations);

The purpose of having a maximum size is to avoid that the file on disk grows indefinitely.

max_number_of_locations is the maximum number of GFile locations for which metadata are kept. This function discards the least recently accessed metadata if needed.

If max_number_of_locations is -1, a default internal value is used that should fit most applications' needs.

Parameters

manager	the TeplMetadataManager.
max_number_of_locations	the maximum size, or -1 for the default value.

Since: 5.0

tepl_metadata_manager_load_from_disk ()

gboolean
tepl_metadata_manager_load_from_disk (TeplMetadataManager *manager,
                                      GFile *from_file,
                                      GError **error);

Loads synchronously all the metadata from from_file into manager .

A good moment to call this function is on application startup, see the “startup” signal.

Parameters

manager	the TeplMetadataManager.
from_file	the GFile to load metadata from.
error	location to a `NULL` GError, or `NULL`.

Returns

whether the operation was successful.

Since: 5.0

tepl_metadata_manager_save_to_disk ()

gboolean
tepl_metadata_manager_save_to_disk (TeplMetadataManager *manager,
                                    GFile *to_file,
                                    gboolean trim,
                                    GError **error);

Saves synchronously all the metadata from manager to to_file . The parent directories of to_file are created if needed.

A good moment to call this function is on application shutdown, see the “shutdown” signal.

Parameters

manager	the TeplMetadataManager.
to_file	the GFile to save metadata to.
trim	if `TRUE`, `tepl_metadata_manager_trim()` is called with -1.
error	location to a `NULL` GError, or `NULL`.

Returns

whether the operation was successful.

Since: 5.0

tepl_metadata_manager_copy_from ()

void
tepl_metadata_manager_copy_from (TeplMetadataManager *from_manager,
                                 GFile *for_location,
                                 TeplMetadata *to_metadata);

Copies the metadata stored in from_manager for for_location into to_metadata .

If to_metadata already contains a key that is also present in from_manager , the value in to_metadata is overwritten.

If to_metadata already contains a key that is not present in from_manager , the key/value pair is kept in to_metadata , it is not erased.

Parameters

from_manager	the TeplMetadataManager.
for_location	a GFile.
to_metadata	a TeplMetadata.

Since: 5.0

tepl_metadata_manager_merge_into ()

void
tepl_metadata_manager_merge_into (TeplMetadataManager *into_manager,
                                  GFile *for_location,
                                  TeplMetadata *from_metadata);

Merges the metadata from from_metadata into into_manager for for_location .

If a key from from_metadata has been set to NULL, the key/value pair is removed from into_manager . In other words that key/value pair will not be saved at all when calling tepl_metadata_manager_save_to_disk().

If into_manager already contains a key that is not present in from_metadata , the key/value pair is kept in into_manager , it is not erased.

Parameters

into_manager	the TeplMetadataManager.
for_location	a GFile.
from_metadata	a TeplMetadata.

Since: 5.0

Types and Values

struct TeplMetadataManager

struct TeplMetadataManager;