Greeter Interface

Greeter Interface — Make a connection to the LightDM daemon and authenticate users

Synopsis

#include <lightdm.h>

void                (*show_message)                     (LightDMGreeter *greeter,
                                                         const gchar *text,
                                                         LightDMMessageType type);
void                (*show_prompt)                      (LightDMGreeter *greeter,
                                                         const gchar *text,
                                                         LightDMPromptType type);
void                (*authentication_complete)          (LightDMGreeter *greeter);
void                (*autologin_timer_expired)          (LightDMGreeter *greeter);
enum                LightDMMessageType;
enum                LightDMPromptType;
LightDMGreeter *    lightdm_greeter_new                 (void);
gboolean            lightdm_greeter_connect_sync        (LightDMGreeter *greeter,
                                                         GError **error);
const gchar *       lightdm_greeter_get_default_session_hint
                                                        (LightDMGreeter *greeter);
const gchar *       lightdm_greeter_get_hint            (LightDMGreeter *greeter,
                                                         const gchar *name);
gboolean            lightdm_greeter_get_has_guest_account_hint
                                                        (LightDMGreeter *greeter);
gboolean            lightdm_greeter_get_hide_users_hint (LightDMGreeter *greeter);
const gchar *       lightdm_greeter_get_select_user_hint
                                                        (LightDMGreeter *greeter);
gboolean            lightdm_greeter_get_select_guest_hint
                                                        (LightDMGreeter *greeter);
const gchar *       lightdm_greeter_get_autologin_user_hint
                                                        (LightDMGreeter *greeter);
gboolean            lightdm_greeter_get_autologin_guest_hint
                                                        (LightDMGreeter *greeter);
gint                lightdm_greeter_get_autologin_timeout_hint
                                                        (LightDMGreeter *greeter);
void                lightdm_greeter_cancel_autologin    (LightDMGreeter *greeter);
void                lightdm_greeter_authenticate        (LightDMGreeter *greeter,
                                                         const gchar *username);
void                lightdm_greeter_authenticate_as_guest
                                                        (LightDMGreeter *greeter);
void                lightdm_greeter_respond             (LightDMGreeter *greeter,
                                                         const gchar *response);
void                lightdm_greeter_cancel_authentication
                                                        (LightDMGreeter *greeter);
gboolean            lightdm_greeter_get_in_authentication
                                                        (LightDMGreeter *greeter);
gboolean            lightdm_greeter_get_is_authenticated
                                                        (LightDMGreeter *greeter);
const gchar *       lightdm_greeter_get_authentication_user
                                                        (LightDMGreeter *greeter);
gboolean            lightdm_greeter_start_session_sync  (LightDMGreeter *greeter,
                                                         const gchar *session,
                                                         GError **error);

Description

LightDMGreeter is an object that manages the connection to the LightDM server and provides common greeter functionality.

Example 1. Example Greeter

int main ()
{
    GMainLoop *main_loop;
    LightDMGreeter *greeter
    main_loop = g_main_loop_new ();
    greeter = lightdm_greeter_new ();
    g_object_connect (greeter, "show-prompt", G_CALLBACK (show_prompt_cb), NULL);
    g_object_connect (greeter, "authentication-complete", G_CALLBACK (authentication_complete_cb), NULL);
    // Connect to LightDM daemon
    if (!lightdm_greeter_connect_sync (greeter, NULL))
        return EXIT_FAILURE;
    // Start authentication
    lightdm_greeter_authenticate (greeter, NULL);
    g_main_loop_run (main_loop);
    return EXIT_SUCCESS;
}
static void show_prompt_cb (LightDMGreeter *greeter, const char *text, LightDMPromptType type)
{
    // Show the user the message and prompt for some response
    gchar *secret = prompt_user (text, type);
    // Give the result to the user
    lightdm_greeter_respond (greeter, response);
}
static void authentication_complete_cb (LightDMGreeter *greeter)
{
    // Start the session
    if (!lightdm_greeter_get_is_authenticated (greeter) ||
        !lightdm_greeter_start_session_sync (greeter, NULL))
    {
        // Failed authentication, try again
        lightdm_greeter_authenticate (greeter, NULL);
    }
}


Details

show_message ()

void                (*show_message)                     (LightDMGreeter *greeter,
                                                         const gchar *text,
                                                         LightDMMessageType type);


show_prompt ()

void                (*show_prompt)                      (LightDMGreeter *greeter,
                                                         const gchar *text,
                                                         LightDMPromptType type);


authentication_complete ()

void                (*authentication_complete)          (LightDMGreeter *greeter);


autologin_timer_expired ()

void                (*autologin_timer_expired)          (LightDMGreeter *greeter);


enum LightDMMessageType

typedef enum {
    LIGHTDM_MESSAGE_TYPE_INFO,
    LIGHTDM_MESSAGE_TYPE_ERROR
} LightDMMessageType;

LIGHTDM_MESSAGE_TYPE_INFO

Informational message.

LIGHTDM_MESSAGE_TYPE_ERROR

Error message.

enum LightDMPromptType

typedef enum {
    LIGHTDM_PROMPT_TYPE_QUESTION,
    LIGHTDM_PROMPT_TYPE_SECRET
} LightDMPromptType;

LIGHTDM_PROMPT_TYPE_QUESTION

Prompt is a question. The information can be shown as it is entered.

LIGHTDM_PROMPT_TYPE_SECRET

Prompt is for secret information. The entered information should be obscured so it can't be publically visible.

lightdm_greeter_new ()

LightDMGreeter *    lightdm_greeter_new                 (void);

Create a new greeter.

Returns :

the new LightDMGreeter

lightdm_greeter_connect_sync ()

gboolean            lightdm_greeter_connect_sync        (LightDMGreeter *greeter,
                                                         GError **error);

Connects the greeter to the display manager. Will block until connected.

greeter :

The greeter to connect

error :

return location for a GError, or NULL

Returns :

TRUE if successfully connected

lightdm_greeter_get_default_session_hint ()

const gchar *       lightdm_greeter_get_default_session_hint
                                                        (LightDMGreeter *greeter);

Get the default session to use.

greeter :

A LightDMGreeter

Returns :

The session name

lightdm_greeter_get_hint ()

const gchar *       lightdm_greeter_get_hint            (LightDMGreeter *greeter,
                                                         const gchar *name);

Get a hint.

greeter :

A LightDMGreeter

name :

The hint name to query.

Returns :

The value for this hint or NULL if not set.

lightdm_greeter_get_has_guest_account_hint ()

gboolean            lightdm_greeter_get_has_guest_account_hint
                                                        (LightDMGreeter *greeter);

Check if guest sessions are supported.

greeter :

A LightDMGreeter

Returns :

TRUE if guest sessions are supported.

lightdm_greeter_get_hide_users_hint ()

gboolean            lightdm_greeter_get_hide_users_hint (LightDMGreeter *greeter);

Check if user accounts should be shown. If this is TRUE then the list of accounts should be taken from LightDMUserList and displayed in the greeter for the user to choose from. Note that this list can be empty and it is recommended you show a method for the user to enter a username manually.

If this option is shown the greeter should only allow these users to be chosen for login unless the manual login hint is set.

greeter :

A LightDMGreeter

Returns :

TRUE if the available users should not be shown.

lightdm_greeter_get_select_user_hint ()

const gchar *       lightdm_greeter_get_select_user_hint
                                                        (LightDMGreeter *greeter);

Get the user to select by default.

greeter :

A LightDMGreeter

Returns :

A username

lightdm_greeter_get_select_guest_hint ()

gboolean            lightdm_greeter_get_select_guest_hint
                                                        (LightDMGreeter *greeter);

Check if the guest account should be selected by default.

greeter :

A LightDMGreeter

Returns :

TRUE if the guest account should be selected by default.

lightdm_greeter_get_autologin_user_hint ()

const gchar *       lightdm_greeter_get_autologin_user_hint
                                                        (LightDMGreeter *greeter);

Get the user account to automatically logg into when the timer expires.

greeter :

A LightDMGreeter

Returns :

The user account to automatically log into.

lightdm_greeter_get_autologin_guest_hint ()

gboolean            lightdm_greeter_get_autologin_guest_hint
                                                        (LightDMGreeter *greeter);

Check if the guest account should be automatically logged into when the timer expires.

greeter :

A LightDMGreeter

Returns :

TRUE if the guest account should be automatically logged into.

lightdm_greeter_get_autologin_timeout_hint ()

gint                lightdm_greeter_get_autologin_timeout_hint
                                                        (LightDMGreeter *greeter);

Get the number of seconds to wait before automaitcally logging in.

greeter :

A LightDMGreeter

Returns :

The number of seconds to wait before automatically logging in or 0 for no timeout.

lightdm_greeter_cancel_autologin ()

void                lightdm_greeter_cancel_autologin    (LightDMGreeter *greeter);

Cancel the automatic login.

greeter :

A LightDMGreeter

lightdm_greeter_authenticate ()

void                lightdm_greeter_authenticate        (LightDMGreeter *greeter,
                                                         const gchar *username);

Starts the authentication procedure for a user.

greeter :

A LightDMGreeter

username :

A username or NULL to prompt for a username. [allow-none]

lightdm_greeter_authenticate_as_guest ()

void                lightdm_greeter_authenticate_as_guest
                                                        (LightDMGreeter *greeter);

Starts the authentication procedure for the guest user.

greeter :

A LightDMGreeter

lightdm_greeter_respond ()

void                lightdm_greeter_respond             (LightDMGreeter *greeter,
                                                         const gchar *response);

Provide response to a prompt. May be one in a series.

greeter :

A LightDMGreeter

response :

Response to a prompt

lightdm_greeter_cancel_authentication ()

void                lightdm_greeter_cancel_authentication
                                                        (LightDMGreeter *greeter);

Cancel the current user authentication.

greeter :

A LightDMGreeter

lightdm_greeter_get_in_authentication ()

gboolean            lightdm_greeter_get_in_authentication
                                                        (LightDMGreeter *greeter);

Checks if the greeter is in the process of authenticating.

greeter :

A LightDMGreeter

Returns :

TRUE if the greeter is authenticating a user.

lightdm_greeter_get_is_authenticated ()

gboolean            lightdm_greeter_get_is_authenticated
                                                        (LightDMGreeter *greeter);

Checks if the greeter has successfully authenticated.

greeter :

A LightDMGreeter

Returns :

TRUE if the greeter is authenticated for login.

lightdm_greeter_get_authentication_user ()

const gchar *       lightdm_greeter_get_authentication_user
                                                        (LightDMGreeter *greeter);

Get the user that is being authenticated.

greeter :

A LightDMGreeter

Returns :

The username of the authentication user being authenticated or NULL if no authentication in progress.

lightdm_greeter_start_session_sync ()

gboolean            lightdm_greeter_start_session_sync  (LightDMGreeter *greeter,
                                                         const gchar *session,
                                                         GError **error);

Start a session for the authenticated user.

greeter :

A LightDMGreeter

session :

The session to log into or NULL to use the default. [allow-none]

error :

return location for a GError, or NULL

Returns :

TRUE if the session was started.