r4097: Removed GNOME-VFS from --version output; we never use it now (Thomas Leonard).

[rox-filer.git] / ROX-Filer / src / main.c

/*
 * $Id$
 *
 * ROX-Filer, filer for the ROX desktop project
 * Copyright (C) 2005, the ROX-Filer team.
 *
 * 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., 59 Temple
 * Place, Suite 330, Boston, MA  02111-1307  USA
 */

/* main.c - parses command-line options and parameters, plus some global
 *          housekeeping.
 *
 * New to the code and feeling lost? Read global.h now.
 */

#include "config.h"

#include <stdlib.h>
#include <stdio.h>
#include <sys/types.h>
#include <signal.h>
#include <string.h>
#include <sys/wait.h>
#include <unistd.h>
#include <fcntl.h>
#include <pwd.h>
#include <grp.h>
#include <libxml/parser.h>

#ifdef HAVE_GETOPT_LONG
#  include <getopt.h>
#endif

#include <gtk/gtk.h>
#include <gdk/gdkx.h>           /* For rox_x_error */

#include "global.h"

#include "main.h"
#include "support.h"
#include "gui_support.h"
#include "filer.h"
#include "display.h"
#include "mount.h"
#include "menu.h"
#include "dnd.h"
#include "options.h"
#include "choices.h"
#include "type.h"
#include "pixmaps.h"
#include "dir.h"
#include "diritem.h"
#include "action.h"
#include "i18n.h"
#include "remote.h"
#include "pinboard.h"
#include "run.h"
#include "toolbar.h"
#include "bind.h"
#include "panel.h"
#include "session.h"
#include "minibuffer.h"
#include "xtypes.h"

int number_of_windows = 0;      /* Quit when this reaches 0 again... */
int to_wakeup_pipe = -1;        /* Write here to get noticed */

/* Information about the ROX-Filer process */
uid_t euid;
gid_t egid;
int ngroups;                    /* Number of supplemental groups */
gid_t *supplemental_groups = NULL;

/* Message to display at the top of each filer window */
const gchar *show_user_message = NULL;

int home_dir_len;
const char *home_dir, *app_dir;

GtkTooltips *tooltips = NULL;

#define COPYING                                                         \
             N_("Copyright (C) 2005 Thomas Leonard.\n"                  \
                "ROX-Filer comes with ABSOLUTELY NO WARRANTY,\n"        \
                "to the extent permitted by law.\n"                     \
                "You may redistribute copies of ROX-Filer\n"            \
                "under the terms of the GNU General Public License.\n"  \
                "For more information about these matters, "            \
                "see the file named COPYING.\n")

#ifdef HAVE_GETOPT_LONG
#  define USAGE   N_("Try `ROX-Filer/AppRun --help' for more information.\n")
#  define SHORT_ONLY_WARNING ""
#else
#  define USAGE   N_("Try `ROX-Filer/AppRun -h' for more information.\n")
#  define SHORT_ONLY_WARNING    \
                _("NOTE: Your system does not support long options - \n" \
                "you must use the short versions instead.\n\n")
#endif

#define BUGS_TO "<rox-devel@lists.sourceforge.net>"

#define HELP N_("Usage: ROX-Filer/AppRun [OPTION]... [FILE]...\n"       \
       "Open each directory or file listed, or the current working\n"   \
       "directory if no arguments are given.\n\n"                       \
       "  -b, --border=PANEL    open PANEL as a border panel\n" \
       "  -B, --bottom=PANEL    open PAN as a bottom-edge panel\n"      \
       "  -c, --client-id=ID    used for session management\n"          \
       "  -d, --dir=DIR         open DIR as directory (not application)\n"  \
       "  -D, --close=DIR       close DIR and its subdirectories\n"     \
       "  -h, --help            display this help and exit\n"           \
       "  -l, --left=PANEL      open PAN as a left-edge panel\n"        \
       "  -m, --mime-type=FILE  print MIME type of FILE and exit\n" \
       "  -n, --new             start new copy; for debugging the filer\n"  \
       "  -p, --pinboard=PIN    use pinboard PIN as the pinboard\n"     \
       "  -r, --right=PANEL     open PAN as a right-edge panel\n"       \
       "  -R, --RPC             invoke method call read from stdin\n"   \
       "  -s, --show=FILE       open a directory showing FILE\n"        \
       "  -S, --rox-session     use default panel and pinboard options, and -n\n"\
       "  -t, --top=PANEL       open PANEL as a top-edge panel\n"       \
       "  -u, --user            show user name in each window \n"       \
       "  -v, --version         display the version information and exit\n"   \
       "  -x, --examine=FILE    FILE has changed - re-examine it\n"     \
       "\nReport bugs to " BUGS_TO ".\n"                \
       "Home page (including updated versions): http://rox.sourceforge.net/\n")

#define SHORT_OPS "c:d:t:b:l:r:B:op:s:hvnux:m:D:RS"

#ifdef HAVE_GETOPT_LONG
static struct option long_opts[] =
{
        {"dir", 1, NULL, 'd'},
        {"top", 1, NULL, 't'},
        {"bottom", 1, NULL, 'B'},
        {"border", 1, NULL, 'b'},
        {"left", 1, NULL, 'l'},
        {"override", 0, NULL, 'o'},
        {"pinboard", 1, NULL, 'p'},
        {"right", 1, NULL, 'r'},
        {"help", 0, NULL, 'h'},
        {"version", 0, NULL, 'v'},
        {"user", 0, NULL, 'u'},
        {"new", 0, NULL, 'n'},
        {"RPC", 0, NULL, 'R'},
        {"show", 1, NULL, 's'},
        {"rox-session", 0, NULL, 'S'},
        {"examine", 1, NULL, 'x'},
        {"close", 1, NULL, 'D'},
        {"mime-type", 1, NULL, 'm'},
        {"client-id", 1, NULL, 'c'},
        {NULL, 0, NULL, 0},
};
#endif

/* Take control of panels away from WM? */
Option o_override_redirect;

/* Options used when we are called by ROX-Session */
enum {
        SESSION_PANEL_ONLY,
        SESSION_PINBOARD_ONLY,
        SESSION_BOTH,
};
Option o_session_panel_or_pin;
Option o_session_panel_name;
Option o_session_pinboard_name;

/* Always start a new filer, even if one seems to be already running */
gboolean new_copy = FALSE;

/* Maps child PIDs to Callback pointers */
static GHashTable *death_callbacks = NULL;
static gboolean child_died_flag = FALSE;

Option o_dnd_no_hostnames;

/* Static prototypes */
static void show_features(void);
static void soap_add(xmlNodePtr body,
                           xmlChar *function,
                           const xmlChar *arg1_name, const xmlChar *arg1_value,
                           const xmlChar *arg2_name, const xmlChar *arg2_value);
static void child_died(int signum);
static void child_died_callback(void);
static void wake_up_cb(gpointer data, gint source, GdkInputCondition condition);
static void xrandr_size_change(GdkScreen *screen, gpointer user_data);
static void add_default_panel_and_pinboard(xmlNodePtr body);
static GList *build_launch(Option *option, xmlNode *node, guchar *label);

/****************************************************************
 *                      EXTERNAL INTERFACE                      *
 ****************************************************************/

/* The value that goes with an option */
#define VALUE (*optarg == '=' ? optarg + 1 : optarg)

static int rox_x_error(Display *display, XErrorEvent *error)
{
        gchar buf[64];

        XGetErrorText(display, error->error_code, buf, 63);

        g_warning ("The program '%s' received an X Window System error.\n"
                        "This probably reflects a bug in the program.\n"
                        "The error was '%s'.\n"
                        "  (Details: serial %ld error_code %d request_code %d minor_code %d)\n"
                        "  (Note to programmers: normally, X errors are reported asynchronously;\n"
                        "   that is, you will receive the error a while after causing it.\n"
                        "   To debug your program, run it with the --sync command line\n"
                        "   option to change this behavior. You can then get a meaningful\n"
                        "   backtrace from your debugger.)",
                        g_get_prgname (),
                        buf,
                        error->serial, 
                        error->error_code, 
                        error->request_code,
                        error->minor_code);

        /* Try to cope with BadWindow errors */
        if (error->error_code == BadWindow || error->error_code == BadDrawable)
        {
                g_warning(_("We got a BadWindow error from the X server. "
                            "This might be due to this GTK bug (during drag-and-drop?):\n"
                            "http://bugzilla.gnome.org/show_bug.cgi?id=152151\n"
                            "Trying to continue..."));
                return 0;
        }

        abort();
}

/* Parses the command-line to work out what the user wants to do.
 * Tries to send the request to an already-running copy of the filer.
 * If that fails, it initialises all the other modules and executes the
 * request itself.
 */
int main(int argc, char **argv)
{
        int              wakeup_pipe[2];
        int              i;
        struct sigaction act;
        guchar          *tmp, *dir;
        gchar *client_id = NULL;
        gboolean        show_user = FALSE;
        xmlDocPtr       rpc, soap_rpc = NULL, reply;
        xmlNodePtr      body;

        home_dir = g_get_home_dir();
        home_dir_len = strlen(home_dir);
        app_dir = g_strdup(getenv("APP_DIR"));

        /* Get internationalisation up and running. This requires the
         * choices system, to discover the user's preferred language.
         */
        choices_init();
        options_init();
        i18n_init();
        xtype_init();

        if (!app_dir)
        {
                g_warning("APP_DIR environment variable was unset!\n"
                        "Use the AppRun script to invoke ROX-Filer...\n");
                app_dir = g_get_current_dir();
        }
#ifdef HAVE_UNSETENV 
        else
        {
                /* Don't pass it on to our child processes... */
                unsetenv("APP_DIR");
        }
#endif

        /* Sometimes we want to take special action when a child
         * process exits. This hash table is used to convert the
         * child's PID to the callback function.
         */
        death_callbacks = g_hash_table_new(NULL, NULL);

        /* Find out some information about ourself */
        euid = geteuid();
        egid = getegid();
        ngroups = getgroups(0, NULL);
        if (ngroups < 0)
                ngroups = 0;
        else if (ngroups > 0)
        {
                supplemental_groups = g_malloc(sizeof(gid_t) * ngroups);
                getgroups(ngroups, supplemental_groups);
        }

        if (argc == 2 && strcmp(argv[1], "-v") == 0)
        {
                /* This is used by install.sh to test if the filer
                 * compiled OK. Do this test before gtk_init so that
                 * we don't need an X server to install.
                 */
                g_print("ROX-Filer %s\n", VERSION);
                g_print(_(COPYING));
                show_features();
                return EXIT_SUCCESS;
        }

        option_add_int(&o_override_redirect, "override_redirect", FALSE);

        option_add_int(&o_session_panel_or_pin, "session_panel_or_pin",
                       SESSION_BOTH);
        option_add_string(&o_session_panel_name, "session_panel_name",
                          "Default");
        option_add_string(&o_session_pinboard_name, "session_pinboard_name",
                          "Default");
        option_register_widget("launch", build_launch);

        /* The idea here is to convert the command-line arguments
         * into a SOAP RPC.
         * We attempt to invoke the call on an already-running copy of
         * the filer if possible, or execute it ourselves if not.
         */
        rpc = soap_new(&body);

        /* Note: must do this before checking our options,
         * otherwise we report an error for Gtk's options.
         */
        gtk_init(&argc, &argv);
        /* Set a default style for the collection widget */
        gtk_rc_parse_string("style \"rox-default-collection-style\" {\n"
                "  bg[NORMAL] = \"#f3f3f3\"\n"
                "  fg[NORMAL] = \"#000000\"\n"
                "  bg[INSENSITIVE] = \"#bfbfbf\"\n"
                "  fg[INSENSITIVE] = \"#000000\"\n"
                "}\n"
                "style \"rox-default-pinboard-style\" {\n"
                "  bg[NORMAL] = \"#666666\"\n"
                "}\n"
                "widget \"rox-pinboard\" style : gtk "
                "\"rox-default-pinboard-style\"\n"

                "class \"Collection\" style : gtk "
                "\"rox-default-collection-style\"\n");

        g_signal_connect(gdk_screen_get_default(), "size-changed",
                         G_CALLBACK(xrandr_size_change), NULL);

        /* Process each option in turn */
        while (1)
        {
                int     c;
#ifdef HAVE_GETOPT_LONG
                int     long_index;
                c = getopt_long(argc, argv, SHORT_OPS,
                                long_opts, &long_index);
#else
                c = getopt(argc, argv, SHORT_OPS);
#endif

                if (c == EOF)
                        break;          /* No more options */
                
                switch (c)
                {
                        case 'n':
                                new_copy = TRUE;
                                break;
                        case 'o':
                                info_message(_("The -o argument is no longer "
                                        "used. You can turn on override "
                                        "redirect from the Options box "
                                        "instead."));
                                break;
                        case 'v':
                                g_print("ROX-Filer %s\n", VERSION);
                                g_print("%s", _(COPYING));
                                show_features();
                                return EXIT_SUCCESS;
                        case 'h':
                                g_print("%s", _(HELP));
                                g_print("%s", _(SHORT_ONLY_WARNING));
                                return EXIT_SUCCESS;
                        case 'D':
                        case 'd':
                        case 'x':
                                /* Argument is a path */
                                if (c == 'd' && VALUE[0] == '/')
                                        tmp = g_strdup(VALUE);
                                else
                                        tmp = pathdup(VALUE);
                                soap_add(body,
                                        c == 'D' ? "CloseDir" :
                                        c == 'd' ? "OpenDir" :
                                        c == 'x' ? "Examine" : "Unknown",
                                        "Filename", tmp,
                                        NULL, NULL);
                                g_free(tmp);
                                break;
                        case 's':
                                tmp = g_path_get_dirname(VALUE);
                                
                                if (tmp[0] == '/')
                                        dir = NULL;
                                else
                                        dir = pathdup(tmp);

                                soap_add(body, "Show",
                                        "Directory", dir ? dir : tmp,
                                        "Leafname", g_basename(VALUE));
                                g_free(tmp);
                                g_free(dir);
                                break;
                        case 'l':
                        case 'r':
                        case 't':
                        case 'B':
                                /* Argument is a leaf (or starts with /) */
                                soap_add(body, "Panel", "Name", VALUE,
                                         "Side", c == 'l' ? "Left" :
                                                 c == 'r' ? "Right" :
                                                 c == 't' ? "Top" :
                                                 c == 'B' ? "Bottom" :
                                                 "Unkown");
                                break;
                        case 'b':
                                /* Argument is a leaf (or starts with /) */
                                if (*VALUE)
                                        soap_add(body, "Panel", "Name", VALUE,
                                                        NULL, NULL);
                                else
                                        soap_add(body, "Panel",
                                                        "Side", "Bottom",
                                                        NULL, NULL);
                                break;
                        case 'p':
                                soap_add(body, "Pinboard",
                                                "Name", VALUE, NULL, NULL);
                                break;
                        case 'u':
                                show_user = TRUE;
                                break;
                        case 'm':
                        {
                                MIME_type *type;
                                type_init();
                                diritem_init();
                                pixmaps_init();
                                type = type_get_type(VALUE);
                                printf("%s/%s\n", type->media_type,
                                                type->subtype);
                                return EXIT_SUCCESS;
                        }
                        case 'c':
                                client_id = g_strdup(VALUE);
                                break;
                        case 'R':
                                soap_rpc = xmlParseFile("-");
                                if (!soap_rpc)
                                        g_error("Invalid XML in RPC");
                                break;

                        case 'S':
                                new_copy = TRUE;
                                add_default_panel_and_pinboard(body);
                                break;

                        default:
                                printf(_(USAGE));
                                return EXIT_FAILURE;
                }
        }

        tooltips = gtk_tooltips_new();

        if (euid == 0 || show_user)
                show_user_message = g_strdup_printf(_("Running as user '%s'"), 
                                                    user_name(euid));
        
        /* Add each remaining (non-option) argument to the list of files
         * to run.
         */
        i = optind;
        while (i < argc)
        {
                tmp = pathdup(argv[i++]);

                soap_add(body, "Run", "Filename", tmp, NULL, NULL);

                g_free(tmp);
        }

        if (soap_rpc)
        {
                if (body->xmlChildrenNode)
                        g_error("Can't use -R with other options - sorry!");
                xmlFreeDoc(rpc);
                body = NULL;
                rpc = soap_rpc;
        }
        else if (!body->xmlChildrenNode)
        {
                /* The user didn't request any action. Open the current
                 * directory.
                 */
                guchar  *dir;

                dir = g_get_current_dir();
                soap_add(body, "OpenDir", "Filename", dir, NULL, NULL);
                g_free(dir);
        }

        option_add_int(&o_dnd_no_hostnames, "dnd_no_hostnames", 1);

        /* Try to send the request to an already-running copy of the filer */
        gui_support_init();
        if (remote_init(rpc, new_copy))
                return EXIT_SUCCESS;    /* It worked - exit */

        /* Put ourselves into the background (so 'rox' always works the
         * same, whether we're already running or not).
         * Not for -n, though (helps when debugging).
         */
        if (!new_copy)
        {
                int fd;
                pid_t child;

                child = fork();
                if (child > 0)
                        _exit(0);       /* Parent exits */
                /* Otherwise we're the child (or an error occurred - ignore
                 * it!).
                 */

                /* Close stdin. We don't need it, and it can cause problems if
                 * a child process wants a password, etc...
                 */
                fd = open("/dev/null", O_RDONLY);
                if (fd > 0)
                {
                        close(0);
                        dup2(fd, 0);
                        close(fd);
                }
        }

        /* Initialize the rest of the filer... */

        pixmaps_init();

        dnd_init();
        bind_init();
        dir_init();
        diritem_init();
        menu_init();
        minibuffer_init();
        filer_init();
        toolbar_init();
        display_init();
        mount_init();
        type_init();
        action_init();

        pinboard_init();
        panel_init();

        /* Let everyone update */
        options_notify();

        /* When we get a signal, we can't do much right then. Instead,
         * we send a char down this pipe, which causes the main loop to
         * deal with the event next time we're idle.
         */
        pipe(wakeup_pipe);
        close_on_exec(wakeup_pipe[0], TRUE);
        close_on_exec(wakeup_pipe[1], TRUE);
        gdk_input_add_full(wakeup_pipe[0], GDK_INPUT_READ, wake_up_cb,
                        NULL, NULL);
        to_wakeup_pipe = wakeup_pipe[1];

        /* If the pipe is full then we're going to get woken up anyway... */
        set_blocking(to_wakeup_pipe, FALSE);

        /* Let child processes die */
        act.sa_handler = child_died;
        sigemptyset(&act.sa_mask);
        act.sa_flags = SA_NOCLDSTOP;
        sigaction(SIGCHLD, &act, NULL);

        /* Ignore SIGPIPE - check for EPIPE errors instead */
        act.sa_handler = SIG_IGN;
        sigemptyset(&act.sa_mask);
        act.sa_flags = 0;
        sigaction(SIGPIPE, &act, NULL);

        /* Set up session managament if available */
        session_init(client_id);
        g_free(client_id);

        /* See if we need to migrate the Choices directories*/
        choices_migrate();

        /* Finally, execute the request */
        reply = run_soap(rpc);
        xmlFreeDoc(rpc);
        if (reply)
        {
                /* Write the result, if any, to stdout */
                save_xml_file(reply, "-");
                xmlFreeDoc(reply);
        }

        /* Try to find out why we crash with GTK 2.4 */
        XSetErrorHandler(rox_x_error);

        /* Enter the main loop, processing events until all our windows
         * are closed.
         */
        if (number_of_windows > 0)
                gtk_main();

        return EXIT_SUCCESS;
}

/* Register a function to be called when process number 'child' dies. */
void on_child_death(gint child, CallbackFn callback, gpointer data)
{
        Callback        *cb;

        g_return_if_fail(callback != NULL);

        cb = g_new(Callback, 1);

        cb->callback = callback;
        cb->data = data;

        g_hash_table_insert(death_callbacks, GINT_TO_POINTER(child), cb);
}

void one_less_window(void)
{
        if (--number_of_windows < 1)
                gtk_main_quit();
}

/****************************************************************
 *                      INTERNAL FUNCTIONS                      *
 ****************************************************************/

static void show_features(void)
{
        g_print("\n");
        g_print(_("Compiled with GTK version %s\n"), GTK_VERSION);
        g_print(_("Running with GTK version %d.%d.%d\n"),
                                gtk_major_version,
                                gtk_minor_version,
                                gtk_micro_version);
        g_print("\n-- %s --\n\n", _("features set at compile time"));
        g_print("%s... %s\n", _("Large File Support"),
#ifdef LARGE_FILE_SUPPORT
                _("Yes")
#else
                _("No")
#endif
                );
        g_print("%s... %s\n", _("Dnotify support"),
#ifdef USE_DNOTIFY
                _("Yes")
#else
                _("No")
#endif
               );
        g_print("%s... %s\n", _("Binary compatibility"),
#if defined(HAVE_APSYMBOLS_H) || defined(HAVE_APBUILD_APSYMBOLS_H)
                _("Yes (can run with older glibc versions)")
#else
                _("No (apsymbols.h not found)")
#endif
               );
}

static void soap_add(xmlNodePtr body,
                           xmlChar *function,
                           const xmlChar *arg1_name, const xmlChar *arg1_value,
                           const xmlChar *arg2_name, const xmlChar *arg2_value)
{
        xmlNodePtr node;
        xmlNs *rox;

        rox = xmlSearchNsByHref(body->doc, body, ROX_NS);
        
        node = xmlNewChild(body, rox, function, NULL);

        if (arg1_name)
        {
                xmlNewTextChild(node, rox, arg1_name, arg1_value);
                if (arg2_name)
                        xmlNewTextChild(node, rox, arg2_name, arg2_value);
        }
}

/* This is called as a signal handler; simply ensures that
 * child_died_callback() will get called later.
 */
static void child_died(int signum)
{
        child_died_flag = TRUE;
        write(to_wakeup_pipe, "\0", 1); /* Wake up! */
}

static void child_died_callback(void)
{
        int             status;
        gint            child;

        child_died_flag = FALSE;

        /* Find out which children exited and allow them to die */
        do
        {
                Callback        *cb;

                child = waitpid(-1, &status, WNOHANG);

                if (child == 0 || child == -1)
                        return;

                cb = g_hash_table_lookup(death_callbacks,
                                GINT_TO_POINTER(child));
                if (cb)
                {
                        cb->callback(cb->data);
                        g_hash_table_remove(death_callbacks,
                                        GINT_TO_POINTER(child));
                }

        } while (1);
}

#define BUFLEN 40
/* When data is written to_wakeup_pipe, this gets called from the event
 * loop some time later. Useful for getting out of signal handlers, etc.
 */
static void wake_up_cb(gpointer data, gint source, GdkInputCondition condition)
{
        char buf[BUFLEN];

        read(source, buf, BUFLEN);
        
        if (child_died_flag)
                child_died_callback();
#ifdef USE_DNOTIFY
        if (dnotify_wakeup_flag)
                dnotify_wakeup();
#endif
}

static void xrandr_size_change(GdkScreen *screen, gpointer user_data)
{
        gui_store_screen_geometry(screen);

        panel_update_size();
        pinboard_update_size();
}

static void add_default_panel_and_pinboard(xmlNodePtr body)
{
        char *name;

        if (o_session_panel_or_pin.int_value != SESSION_PANEL_ONLY)
        {
                name=o_session_pinboard_name.value;
                if (!name[0])
                        name="Default";
                soap_add(body, "Pinboard","Name", name, NULL, NULL);
        }
                                        
        if (o_session_panel_or_pin.int_value != SESSION_PINBOARD_ONLY)
        {
                name = o_session_panel_name.value;
                if (!name[0])
                        name="Default";
                
                soap_add(body, "Panel", "Name", name, NULL, NULL);
        }
}

static GtkWidget *launch_button_new(const char *label, const char *uri)
{
        GtkWidget *button;
        GClosure *closure;

        button = button_new_mixed(GTK_STOCK_PREFERENCES, label);
        closure = g_cclosure_new_swap(G_CALLBACK(launch_uri),
                                        g_strdup(uri),
                                        (GClosureNotify) g_free);
        g_signal_connect_closure(button, "clicked", closure, FALSE);

        allow_right_click(button);

        return button;
}

static GList *build_launch(Option *option, xmlNode *node, guchar *label)
{
        GtkWidget *align;
        char *uri;

        g_return_val_if_fail(option == NULL, NULL);
        g_return_val_if_fail(label != NULL, NULL);

        uri = xmlGetProp(node, "uri");

        g_return_val_if_fail(uri != NULL, NULL);

        align = gtk_alignment_new(0, 0.5, 0, 0);

        gtk_container_add(GTK_CONTAINER(align),
                        launch_button_new(_(label), uri));

        g_free(uri);

        return g_list_append(NULL, align);
}