gnome-program

gnome-program — Initialize and retrieve information about a GNOME application.

Synopsis


#include <libgnome/libgnome.h>


enum        GnomeFileDomain;
            GnomeProgram;
            GnomeModuleInfo;
            GnomeModuleRequirement;
void        (*GnomeModuleInitHook)          (const GnomeModuleInfo *mod_info);
void        (*GnomeModuleClassInitHook)     (GnomeProgramClass *klass,
                                             const GnomeModuleInfo *mod_info);
void        (*GnomeModuleHook)              (GnomeProgram *program,
                                             GnomeModuleInfo *mod_info);
GnomeProgram* gnome_program_init            (const char *app_id,
                                             const char *app_version,
                                             const GnomeModuleInfo *module_info,
                                             int argc,
                                             char **argv,
                                             const char *first_property_name,
                                             ...);
GnomeProgram* gnome_program_initv           (GType type,
                                             const char *app_id,
                                             const char *app_version,
                                             const GnomeModuleInfo *module_info,
                                             int argc,
                                             char **argv,
                                             const char *first_property_name,
                                             va_list args);

GnomeProgram* gnome_program_get             (void);
const char* gnome_program_get_human_readable_name
                                            (GnomeProgram *program);
const char* gnome_program_get_app_id        (GnomeProgram *program);
const char* gnome_program_get_app_version   (GnomeProgram *program);
gchar*      gnome_program_locate_file       (GnomeProgram *program,
                                             GnomeFileDomain domain,
                                             const gchar *file_name,
                                             gboolean only_if_exists,
                                             GSList **ret_locations);

void        gnome_program_module_register   (const GnomeModuleInfo *module_info);
gboolean    gnome_program_module_registered (const GnomeModuleInfo *module_info);
const GnomeModuleInfo* gnome_program_module_load
                                            (const char *mod_name);
guint       gnome_program_install_property  (GnomeProgramClass *pclass,
                                             GObjectGetPropertyFunc get_fn,
                                             GObjectSetPropertyFunc set_fn,
                                             GParamSpec *pspec);
poptContext gnome_program_preinit           (GnomeProgram *program,
                                             const char *app_id,
                                             const char *app_version,
                                             int argc,
                                             char **argv);
void        gnome_program_parse_args        (GnomeProgram *program);
void        gnome_program_postinit          (GnomeProgram *program);

#define     GNOME_PARAM_POPT_TABLE
#define     GNOME_PARAM_POPT_FLAGS
#define     GNOME_PARAM_POPT_CONTEXT
#define     GNOME_PARAM_GOPTION_CONTEXT
#define     GNOME_PARAM_CREATE_DIRECTORIES
#define     GNOME_PARAM_ENABLE_SOUND
#define     GNOME_PARAM_ESPEAKER
#define     GNOME_PARAM_APP_ID
#define     GNOME_PARAM_APP_VERSION
#define     GNOME_PARAM_GNOME_PREFIX
#define     GNOME_PARAM_GNOME_SYSCONFDIR
#define     GNOME_PARAM_GNOME_DATADIR
#define     GNOME_PARAM_GNOME_LIBDIR
#define     GNOME_PARAM_APP_PREFIX
#define     GNOME_PARAM_APP_SYSCONFDIR
#define     GNOME_PARAM_APP_DATADIR
#define     GNOME_PARAM_APP_LIBDIR
#define     GNOME_PARAM_HUMAN_READABLE_NAME
#define     GNOME_PARAM_GNOME_PATH
#define     GNOME_PARAM_NONE
#define     GNOME_PROGRAM_STANDARD_PROPERTIES


Description

Details

enum GnomeFileDomain

typedef enum {
    GNOME_FILE_DOMAIN_UNKNOWN = 0,

    /* Gnome installed files */
    GNOME_FILE_DOMAIN_LIBDIR,
    GNOME_FILE_DOMAIN_DATADIR,
    GNOME_FILE_DOMAIN_SOUND,
    GNOME_FILE_DOMAIN_PIXMAP,
    GNOME_FILE_DOMAIN_CONFIG,
    GNOME_FILE_DOMAIN_HELP,

    /* Application files */
    GNOME_FILE_DOMAIN_APP_LIBDIR,
    GNOME_FILE_DOMAIN_APP_DATADIR,
    GNOME_FILE_DOMAIN_APP_SOUND,
    GNOME_FILE_DOMAIN_APP_PIXMAP,
    GNOME_FILE_DOMAIN_APP_CONFIG,
    GNOME_FILE_DOMAIN_APP_HELP
} GnomeFileDomain;

Many of the files that a GNOME application needs to access will be installed in standard locations. For example, GNOME help files will be in one location, while help files specific to the current application might be in another location.

The different types of files are given in this enum. User applications make use of the GNOME_FILE_DOMAIN_APP_* types, which specify locations relative to GNOME_PARAM_APP_DATADIR.

GNOME_FILE_DOMAIN_UNKNOWN An unknown file domain (should never be used).
GNOME_FILE_DOMAIN_LIBDIR Libraries in the main GNOME installation.
GNOME_FILE_DOMAIN_DATADIR Data files in the main GNOME installation.
GNOME_FILE_DOMAIN_SOUND Sound files in the main GNOME installation.
GNOME_FILE_DOMAIN_PIXMAP Pixmap files in the main GNOME installation.
GNOME_FILE_DOMAIN_CONFIG Config files in the main GNOME installation.
GNOME_FILE_DOMAIN_HELP Help files in the main GNOME installation.
GNOME_FILE_DOMAIN_APP_LIBDIR Application specific libraries.
GNOME_FILE_DOMAIN_APP_DATADIR Application specific data files.
GNOME_FILE_DOMAIN_APP_SOUND Application specific sound files.
GNOME_FILE_DOMAIN_APP_PIXMAP Application specific pixmap files.
GNOME_FILE_DOMAIN_APP_CONFIG Application specific config files.
GNOME_FILE_DOMAIN_APP_HELP Application specific help files.

GnomeProgram

typedef struct {
    GObject object;

    GnomeProgramPrivate *_priv;
} GnomeProgram;

A structure containing information about the current application. Initialised during a call to gnome_program_init().

GObject object; A GObject containing the parameters and their values which were set dring initialisation.
GnomeProgramPrivate *_priv; Private data about the program instance.

GnomeModuleInfo

typedef struct {
    const char *name;
    const char *version;
    const char *description;
    GnomeModuleRequirement *requirements; /* last element has NULL version */

    GnomeModuleHook instance_init;
    GnomeModuleHook pre_args_parse, post_args_parse;

#ifdef GNOME_DISABLE_DEPRECATED
    struct poptOption *_options;
#else
    struct poptOption *options;
#endif

    GnomeModuleInitHook init_pass;

    GnomeModuleClassInitHook class_init;

    const char *opt_prefix;
    GnomeModuleGetGOptionGroupFunc get_goption_group_func;
} GnomeModuleInfo;

A structure containing information about a module. This contains descriptive information about the module, as well as how to initialise it and what its dependencies are (chained via the requirements parameter).

const char *name; The module name.
const char *version; The module's version string.
const char *description; A string describing the module (can be NULL).
GnomeModuleRequirement *requirements; A pointer to an array of modules that are required by this module. The last module in the array should have its required_version field set to NULL.
GnomeModuleHook instance_init; A function to call to initialise an instance of this module (can be NULL).
GnomeModuleHook pre_args_parse; A function to call before parsing the arguments for this module (can be NULL).
GnomeModuleHook post_args_parse; A function to call after parsing the arguments for this module (can be NULL).
GnomeModuleClassInitHook class_init; A function to call to initialise this module prior to creating any instances (can be NULL).
const char *opt_prefix; Unused.
GnomeModuleGetGOptionGroupFunc get_goption_group_func;

GnomeModuleRequirement

typedef struct {
    const char *required_version;
    const GnomeModuleInfo *module_info;
} GnomeModuleRequirement;

A structure which allows a module to specify the minimum required versions of modules it depends upon.

const char *required_version; The version required by the parent module.
const GnomeModuleInfo *module_info; A GnomeModuleInfo structure detailing the required module.

GnomeModuleInitHook ()

void        (*GnomeModuleInitHook)          (const GnomeModuleInfo *mod_info);

A function that will be called to allow a module to do any pre-initialisation it might need to do prior to having arguments parsed by the controlling parent module (the parent will do the argument parsing for all modules in the hierarchy).

mod_info : The current module.

GnomeModuleClassInitHook ()

void        (*GnomeModuleClassInitHook)     (GnomeProgramClass *klass,
                                             const GnomeModuleInfo *mod_info);

A function called to perform any class specific setup that is required by each module.

klass : The class of the parent module (which could be this module's class). This will usually be GnomeProgramClass.
mod_info : The current module.

GnomeModuleHook ()

void        (*GnomeModuleHook)              (GnomeProgram *program,
                                             GnomeModuleInfo *mod_info);

A function that is called to perform some intialisation in a module (which could be either the main init function or the pre or post argument parsing phase).

program : The GnomeProgram instance which is being initialised.
mod_info : The current module's GnomeModuleInfo structure.

gnome_program_init ()

GnomeProgram* gnome_program_init            (const char *app_id,
                                             const char *app_version,
                                             const GnomeModuleInfo *module_info,
                                             int argc,
                                             char **argv,
                                             const char *first_property_name,
                                             ...);

Initialises the current GNOME libraries for use by the application.

Every GNOME application will need to call this function (or gnome_program_initv()) early in its lifetime to initialize the various GNOME libraries in a consistent fashion. This function is very flexible in allowing the user to specify which modules should be initialised and any special paramter values that should be passed to these modules (along with processing commandline options).

It loads the specified module_info, which is normally LIBGNOME_MODULE or LIBGNOMEUI_MODULE and pulls in all the dependencies. Programs that are not running in setuid or setgid mode will also load modules specified in the --load-modules and also in the GNOME_MODULES environment variable.

After setting up the module loading, this function then calls (in order) gnome_program_preinit(), gnome_program_parse_args() and gnome_program_postinit().

The following example shows how one might initialise a typical program using a goption table that is defined elsewhere.

Example 1. Initializing a GNOME application (deprecated, using popt)

int main(int argc, char **argv) {
	GnomeProgram *my_app;
	GOptionContext *option_context;
	
	/* We assume PACKAGE and VERSION are set to the program name and version
	 * number respectively. Also, assume that 'options' is a global array of
	 * poptOptions.
	 */
	option_context = g_option_context_new (PACKAGE);
	g_option_context_add_main_entries (option_context, options, NULL);
	my_app = gnome_program_init(PACKAGE, VERSION, LIBGNOMEUI_MODULE,
	                            argc, argv,
				    GNOME_PARAM_OPTION_CONTEXT, option_context,
				    GNOME_PARAM_NONE);
	/* Now process any extra args, etc ... */
}

Even though many applications still use popt for command-line option parsing, it has been deprecated in Gnome-2.14 and its use is discouraged for newly-written code. GNOME applications should aim to use the new GOption API. Here an example that shows how one might initialize a typical program using a GOptionEntry table (see the GLib documentation for a more elaborate example of an option entry table):

Example 2. Initializing a GNOME application (new, using GOption)

int main(int argc, char **argv) {
	gchar **remaining_args = NULL;
	GOptionEntry option_entries[] = {
		/* ... your application's command line options go here ... */
		/* last but not least a special option that collects filenames */
		{ G_OPTION_REMAINING, 0, 0, G_OPTION_ARG_FILENAME_ARRAY,
		  &remaining_args,
		  "Special option that collects any remaining arguments for us" },
		{ NULL }
	};

	GOptionContext *option_context;
	GnomeProgram *my_app;

	option_context = g_option_context_new ("my-app");

	/* if you are using any libraries that have command line options
	 * of their own and provide a GOptionGroup with them, you can
	 * add them here as well using g_option_context_add_group()
	 */

	/* now add our own application's command-line options. If you
	 * are using gettext for translations, you should be using
	 * GETTEXT_PACKAGE here instead of NULL
	 */
	g_option_context_add_main_entries (option_context, option_entries, NULL);

	/* We assume PACKAGE and VERSION are set to the program name and version
	 * number respectively. Also, assume that 'option_entries' is a global
	 * array of GOptionEntry structures.
	 */
	my_app = gnome_program_init(PACKAGE, VERSION,
	                            LIBGNOMEUI_MODULE, argc, argv,
	                            GNOME_PARAM_GOPTION_CONTEXT, option_context,
	                            GNOME_PARAM_NONE);

	/* parse remaining command-line arguments that are not
	 * options (e.g. filenames or URIs or whatever), if any
	 */
	if (remaining_args != NULL) {
	    gint i, num_args;

		num_args = g_strv_length (remaining_args);
		for (i = 0; i < num_args; ++i) {
			/* process remaining_args[i] here */
		}
		g_strfreev (remaining_args);
		remaining_args = NULL;
	}

app_id : Application ID string.
app_version : Application version string.
module_info : The module to init with this program.
argc : The number of commmand line arguments contained in argv.
argv : A string array of command line arguments.
first_property_name : The first item in a NULL-terminated list of attribute name and value pairs (so this will be an attribute name or NULL).
... : The continuation of a NULL-terminated list of attribute name/value pairs.
Returns : A GnomeProgram instance representing the current application.

gnome_program_initv ()

GnomeProgram* gnome_program_initv           (GType type,
                                             const char *app_id,
                                             const char *app_version,
                                             const GnomeModuleInfo *module_info,
                                             int argc,
                                             char **argv,
                                             const char *first_property_name,
                                             va_list args);

Provides a non-varargs form of gnome_program_init(). Users will rarely need to call this function directly.

type : The type of application to be initialized (usually GNOME_TYPE_PROGRAM).
app_id : Application ID string.
app_version : Application version string.
module_info : The modules to init with the application.
argc : The number of command line arguments contained in argv.
argv : A string array of command line arguments.
first_property_name : The first item in a NULL-terminated list of attribute name/value.
args : The remaining elements in the NULL terminated list (of which first_property_name is the first element).
Returns : A GnomeProgram instance representing the current application.

gnome_program_get ()

GnomeProgram* gnome_program_get             (void);

Retrieves an object that stored information about the application's state. Other functions assume this will always return a GnomeProgram object which (if not NULL) has already been initialized.

Returns : The application's GnomeProgram instance, or NULL if it does not exist.

gnome_program_get_human_readable_name ()

const char* gnome_program_get_human_readable_name
                                            (GnomeProgram *program);

This function returns a pointer to a static string that the application has provided as a human readable name. The app should provide the name with the GNOME_PARAM_HUMAN_READABLE_NAME init argument. Returns NULL if no name was set.

program : The application object
Returns : Application human-readable name string.

gnome_program_get_app_id ()

const char* gnome_program_get_app_id        (GnomeProgram *program);

This function returns a pointer to a static string that the application has provided as an identifier. This is not meant as a human-readable identifier so much as a unique identifier for programs and libraries.

program : The program object
Returns : Application ID string.

gnome_program_get_app_version ()

const char* gnome_program_get_app_version   (GnomeProgram *program);

This function returns a pointer to a static string that the application has provided as a version number. This is not meant as a human-readable identifier so much as a unique identifier for programs and libraries.

program : The application object
Returns : Application version string.

gnome_program_locate_file ()

gchar*      gnome_program_locate_file       (GnomeProgram *program,
                                             GnomeFileDomain domain,
                                             const gchar *file_name,
                                             gboolean only_if_exists,
                                             GSList **ret_locations);

This function finds a full path to the file_name located in the specified "domain". A domain is a name for a collection of related files. For example, common domains are "libdir", "pixmap", and "config".

If ret_locations is NULL, only one pathname is returned. Otherwise, alternative paths are returned in ret_locations.

User applications should store files in the GNOME_FILE_DOMAIN_APP_* domains. However you MUST set the correct attributes for GnomeProgram for the APP specific prefixes (during the initialization part of the application).

The ret_locations list and its contents should be freed by the caller, as should the returned string.

program : A valid GnomeProgram object or NULL (in which case the current application is used).
domain : A GnomeFileDomain.
file_name : A file name or path inside the 'domain' to find.
only_if_exists : Only return a full pathname if the specified file actually exists
ret_locations : If this is not NULL, a list of all the possible locations of the file will be returned.
Returns : The full path to the file (if it exists or only_if_exists is FALSE) or NULL.

gnome_program_module_register ()

void        gnome_program_module_register   (const GnomeModuleInfo *module_info);

This function is used to register a module to be initialized by the GNOME library framework. The memory pointed to by module_info must be valid during the whole application initialization process, and the module described by module_info must only use the module_info pointer to register itself.

module_info : A pointer to a GnomeModuleInfo structure describing the module to be initialized

gnome_program_module_registered ()

gboolean    gnome_program_module_registered (const GnomeModuleInfo *module_info);

This method checks to see whether a specific module has been initialized in the specified program.

module_info : A pointer to a GnomeModuleInfo structure describing the module to be queried
Returns : A value indicating whether the specified module has been registered/initialized in the current program

gnome_program_module_load ()

const GnomeModuleInfo* gnome_program_module_load
                                            (const char *mod_name);

Loads a shared library that contains a GnomeModuleInfo dynamic_module_info structure.

mod_name : module name
Returns : The GnomeModuleInfo structure that was loaded, or NULL if the module could not be loaded.

gnome_program_install_property ()

guint       gnome_program_install_property  (GnomeProgramClass *pclass,
                                             GObjectGetPropertyFunc get_fn,
                                             GObjectSetPropertyFunc set_fn,
                                             GParamSpec *pspec);

Install a collection of available properties, their default values and the functions to set and retrieve these properties.

Normal applications will never need to call this function, it is mostly for use by other platform library authors.

pclass : A GnomeProgramClass.
get_fn : A function to get property values.
set_fn : A function to set property values.
pspec : A collection of properties.
Returns : The number of properties installed.

gnome_program_preinit ()

poptContext gnome_program_preinit           (GnomeProgram *program,
                                             const char *app_id,
                                             const char *app_version,
                                             int argc,
                                             char **argv);

This function performs the portion of application initialization that needs to be done prior to command line argument parsing. The poptContext returned can be used for getopt()-style option processing.

program : Application object
app_id : application ID string
app_version : application version string
argc : The number of commmand line arguments contained in 'argv'
argv : A string array of command line arguments
Returns : A poptContext representing the argument parsing state, or NULL if using GOption argument parsing.

gnome_program_parse_args ()

void        gnome_program_parse_args        (GnomeProgram *program);

Parses the command line arguments for the application

program : Application object

gnome_program_postinit ()

void        gnome_program_postinit          (GnomeProgram *program);

Called after gnome_program_parse_args(), this function takes care of post-parse initialization and cleanup

program : Application object

GNOME_PARAM_POPT_TABLE

#define GNOME_PARAM_POPT_TABLE          "popt-table"

Warning

GNOME_PARAM_POPT_TABLE is deprecated and should not be used in newly-written code. 2.14. Use GOption argument parsing instead, with GNOME_PARAM_GOPTION_CONTEXT.

This parameter contains the table of options to be passed to popt (write on init only). Mutually exclusive with using GNOME_PARAM_GOPTION_CONTEXT parameter.


GNOME_PARAM_POPT_FLAGS

#define GNOME_PARAM_POPT_FLAGS          "popt-flags"

Warning

GNOME_PARAM_POPT_FLAGS is deprecated and should not be used in newly-written code. 2.14. Use GOption argument parsing instead.

This parameter contains the flags to use for popt (write on init only).


GNOME_PARAM_POPT_CONTEXT

#define GNOME_PARAM_POPT_CONTEXT        "popt-context"

Warning

GNOME_PARAM_POPT_CONTEXT is deprecated and should not be used in newly-written code. 2.14. Use GOption argument parsing instead.

This parameter contains the context pointer that GnomeProgram is using for popt parsing (readable).


GNOME_PARAM_GOPTION_CONTEXT

#define GNOME_PARAM_GOPTION_CONTEXT     "goption-context"

This parameter contains the GOptionContext pointer that GnomeProgram is using for GOption parsing (write on init only). The GnomeProgram will assume ownership of the passed GOptionContext. Mutually exclusive with using the GNOME_PARAM_POPT_TABLE parameter.

Since 2.14


GNOME_PARAM_CREATE_DIRECTORIES

#define GNOME_PARAM_CREATE_DIRECTORIES  "create-directories"

This parameter contains TRUE if the standard GNOME directories should be created on startup.


GNOME_PARAM_ENABLE_SOUND

#define GNOME_PARAM_ENABLE_SOUND        "enable-sound"

This parameter determines whether or not to enable sound on startup.


GNOME_PARAM_ESPEAKER

#define GNOME_PARAM_ESPEAKER            "espeaker"

This parameter describes how to connect to esd.


GNOME_PARAM_APP_ID

#define GNOME_PARAM_APP_ID              "app-id"

This parameter contains the ID string to use for the application (readable).


GNOME_PARAM_APP_VERSION

#define GNOME_PARAM_APP_VERSION         "app-version"

This parameter contains the application version (readable).


GNOME_PARAM_GNOME_PREFIX

#define GNOME_PARAM_GNOME_PREFIX        "gnome-prefix"

This parameter contains the prefix where the main GNOME system is installed (readable, writable on init only).


GNOME_PARAM_GNOME_SYSCONFDIR

#define GNOME_PARAM_GNOME_SYSCONFDIR    "gnome-sysconfdir"

This parameter contains the prefix where the GNOME configuration files are installed (readable, writable on init only).


GNOME_PARAM_GNOME_DATADIR

#define GNOME_PARAM_GNOME_DATADIR       "gnome-datadir"

This parameter contains the prefix where the GNOME data files are installed (readable, writable on init only).


GNOME_PARAM_GNOME_LIBDIR

#define GNOME_PARAM_GNOME_LIBDIR        "gnome-libdir"

This parameter contains the prefix where the GNOME library files are installed (readable, writable on init only).


GNOME_PARAM_APP_PREFIX

#define GNOME_PARAM_APP_PREFIX          "app-prefix"

This parameter contains the prefix where this application was installed (read / write).


GNOME_PARAM_APP_SYSCONFDIR

#define GNOME_PARAM_APP_SYSCONFDIR      "app-sysconfdir"

This parameter contains the prefix where this application's configuration files are installed (read / write).


GNOME_PARAM_APP_DATADIR

#define GNOME_PARAM_APP_DATADIR         "app-datadir"

This parameter contains the prefix where this application's data files are installed (read / write).


GNOME_PARAM_APP_LIBDIR

#define GNOME_PARAM_APP_LIBDIR          "app-libdir"

This parameter contains the prefix where this application's library files are installed (read / write).


GNOME_PARAM_HUMAN_READABLE_NAME

#define GNOME_PARAM_HUMAN_READABLE_NAME "human-readable-name"

This parameter contains the human readable name of the application (readable).


GNOME_PARAM_GNOME_PATH

#define GNOME_PARAM_GNOME_PATH          "gnome-path"

This parameter contains the path in which to look for installed files (taken from the GNOME2_PATH environment variable).


GNOME_PARAM_NONE

#define GNOME_PARAM_NONE                NULL

Used to terminate a list of parameters and their values.


GNOME_PROGRAM_STANDARD_PROPERTIES

#define     GNOME_PROGRAM_STANDARD_PROPERTIES

When PREFIX, SYSCONFDIR, DATADIR and LIBDIR are defined during the build process, this macro can be used to assign these values to GNOME_PARAM_APP_PREFIX, GNOME_PARAM_APP_SYSCONFDIR, GNOME_PARAM_APP_DATADIR and GNOME_PARAM_APP_LIBDIR respectively so that the GNOME libraries automatically know where to fetch application specific data from.

Every respectable GNOME application should set these variables and use GNOME_PROGRAM_STANDARD_PROPERTIES in the call to gnome_program_init().