r2634: Updates for the new shared MIME database.

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

/*
 * $Id$
 *
 * ROX-Filer, filer for the ROX desktop project
 * Copyright (C) 2003, 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
 */

/* type.c - code for dealing with filetypes */

#include "config.h"

#include <stdlib.h>
#include <stdio.h>
#include <errno.h>
#include <ctype.h>
#include <time.h>
#include <sys/param.h>
#include <fnmatch.h>
#include <sys/types.h>
#include <fcntl.h>

#ifdef WITH_GNOMEVFS
# include <libgnomevfs/gnome-vfs.h>
# include <libgnomevfs/gnome-vfs-mime.h>
# include <libgnomevfs/gnome-vfs-mime-handlers.h>
# include <libgnomevfs/gnome-vfs-application-registry.h>
#endif

#include "global.h"

#include "string.h"
#include "fscache.h"
#include "main.h"
#include "pixmaps.h"
#include "run.h"
#include "gui_support.h"
#include "choices.h"
#include "type.h"
#include "support.h"
#include "diritem.h"
#include "dnd.h"
#include "options.h"
#include "filer.h"
#include "action.h"             /* (for action_chmod) */
#include "xml.h"
#include "dropbox.h"

#define TYPE_NS "http://www.freedesktop.org/standards/shared-mime-info"
enum {SET_MEDIA, SET_TYPE};

/* Colours for file types (same order as base types) */
static gchar *opt_type_colours[][2] = {
        {"display_err_colour",  "#ff0000"},
        {"display_unkn_colour", "#000000"},
        {"display_dir_colour",  "#000080"},
        {"display_pipe_colour", "#444444"},
        {"display_sock_colour", "#ff00ff"},
        {"display_file_colour", "#000000"},
        {"display_cdev_colour", "#000000"},
        {"display_bdev_colour", "#000000"},
        {"display_door_colour", "#ff00ff"},
        {"display_exec_colour", "#006000"},
        {"display_adir_colour", "#006000"}
};
#define NUM_TYPE_COLOURS\
                (sizeof(opt_type_colours) / sizeof(opt_type_colours[0]))

/* Parsed colours for file types */
static Option o_type_colours[NUM_TYPE_COLOURS];
static GdkColor type_colours[NUM_TYPE_COLOURS];

/* Static prototypes */
static void load_mime_types(void);
static void alloc_type_colours(void);
static char *get_action_save_path(GtkWidget *dialog);
static void edit_mime_types(guchar *unused);
static MIME_type *get_mime_type(const gchar *type_name, gboolean can_create);
static GList *build_type_edit(Option *none, xmlNode *node, guchar *label);
static gboolean remove_handler_with_confirm(const guchar *path);

/* When working out the type for a file, this hash table is checked
 * first...
 */
static GHashTable *literal_hash = NULL; /* name -> MIME-type */

/* Maps extensions to MIME_types (eg 'png'-> MIME_type *).
 * Extensions may contain dots; 'tar.gz' matches '*.tar.gz', etc.
 * The hash table is consulted from each dot in the string in turn
 * (First .ps.gz, then try .gz)
 */
static GHashTable *extension_hash = NULL;

/* The first pattern in the list which matches is used */
typedef struct pattern {
        gint len;               /* Used for sorting */
        gchar *glob;
        MIME_type *type;
} Pattern;
static GPtrArray *glob_patterns = NULL; /* [Pattern] */

/* Hash of all allocated MIME types, indexed by "media/subtype".
 * MIME_type structs are never freed; this table prevents memory leaks
 * when rereading the config files.
 */
static GHashTable *type_hash = NULL;

/* Most things on Unix are text files, so this is the default type */
MIME_type *text_plain;
MIME_type *inode_directory;
MIME_type *inode_pipe;
MIME_type *inode_socket;
MIME_type *inode_block_dev;
MIME_type *inode_char_dev;
MIME_type *application_executable;
MIME_type *inode_unknown;
MIME_type *inode_door;

static Option o_display_colour_types;

void type_init(void)
{
        int             i;
        
        extension_hash = g_hash_table_new(g_str_hash, g_str_equal);
        type_hash = g_hash_table_new(g_str_hash, g_str_equal);

        text_plain = get_mime_type("text/plain", TRUE);
        inode_directory = get_mime_type("inode/directory", TRUE);
        inode_pipe = get_mime_type("inode/fifo", TRUE);
        inode_socket = get_mime_type("inode/socket", TRUE);
        inode_block_dev = get_mime_type("inode/blockdevice", TRUE);
        inode_char_dev = get_mime_type("inode/chardevice", TRUE);
        application_executable = get_mime_type("application/x-executable", TRUE);
        inode_unknown = get_mime_type("inode/unknown", TRUE);
        inode_door = get_mime_type("inode/door", TRUE);

        load_mime_types();

        option_register_widget("type-edit", build_type_edit);
        
        option_add_int(&o_display_colour_types, "display_colour_types", TRUE);
        
        for (i = 0; i < NUM_TYPE_COLOURS; i++)
                option_add_string(&o_type_colours[i],
                                  opt_type_colours[i][0],
                                  opt_type_colours[i][1]);
        alloc_type_colours();

        option_add_notify(alloc_type_colours);
}

/* Read-load all the glob patterns.
 * Note: calls filer_update_all.
 */
void reread_mime_files(void)
{
        load_mime_types();
}

/* Returns the MIME_type structure for the given type name. It is looked
 * up in type_hash and returned if found. If not found (and can_create is
 * TRUE) then a new MIME_type is made, added to type_hash and returned.
 * NULL is returned if type_name is not in type_hash and can_create is
 * FALSE, or if type_name does not contain a '/' character.
 */
static MIME_type *get_mime_type(const gchar *type_name, gboolean can_create)
{
        MIME_type *mtype;
        gchar *slash;

        mtype = g_hash_table_lookup(type_hash, type_name);
        if (mtype || !can_create)
                return mtype;

        slash = strchr(type_name, '/');
        g_return_val_if_fail(slash != NULL, NULL);     /* XXX: Report nicely */

        mtype = g_new(MIME_type, 1);
        mtype->media_type = g_strndup(type_name, slash - type_name);
        mtype->subtype = g_strdup(slash + 1);
        mtype->image = NULL;
        mtype->comment = NULL;

        g_hash_table_insert(type_hash, g_strdup(type_name), mtype);

        return mtype;
}

const char *basetype_name(DirItem *item)
{
        if (item->flags & ITEM_FLAG_SYMLINK)
                return _("Sym link");
        else if (item->flags & ITEM_FLAG_MOUNT_POINT)
                return _("Mount point");
        else if (item->flags & ITEM_FLAG_APPDIR)
                return _("App dir");

        switch (item->base_type)
        {
                case TYPE_FILE:
                        return _("File");
                case TYPE_DIRECTORY:
                        return _("Dir");
                case TYPE_CHAR_DEVICE:
                        return _("Char dev");
                case TYPE_BLOCK_DEVICE:
                        return _("Block dev");
                case TYPE_PIPE:
                        return _("Pipe");
                case TYPE_SOCKET:
                        return _("Socket");
                case TYPE_DOOR:
                        return _("Door");
        }
        
        return _("Unknown");
}

/*                      MIME-type guessing                      */

/* Get the type of this file - stats the file and uses that if
 * possible. For regular or missing files, uses the pathname.
 */
MIME_type *type_get_type(const guchar *path)
{
        struct stat     info;
        MIME_type       *type = NULL;
        int             base = TYPE_FILE;
        gboolean        exec = FALSE;

        if (mc_stat(path, &info) == 0)
        {
                base = mode_to_base_type(info.st_mode);
                if (info.st_mode & (S_IXUSR | S_IXGRP | S_IXOTH))
                        exec = TRUE;
        }

        if (base == TYPE_FILE)
                type = type_from_path(path);

        if (!type)
        {
                if (base == TYPE_FILE && exec)
                        type = application_executable;
                else
                        type = mime_type_from_base_type(base);
        }

        return type;
}

/* Returns a pointer to the MIME-type.
 * NULL if we can't think of anything.
 */
MIME_type *type_from_path(const char *path)
{
        const char *ext, *dot, *leafname;
        char *lower;
        MIME_type *type = NULL;
        int     i;

#if 0
# ifdef WITH_GNOMEVFS
        if (o_use_gnomevfs.int_value)
                return get_mime_type(gnome_vfs_mime_type_from_name(path), TRUE);
# endif
#endif

        leafname = g_basename(path);

        type = g_hash_table_lookup(literal_hash, leafname);
        if (type)
                return type;
        lower = g_utf8_strdown(leafname, -1);
        type = g_hash_table_lookup(literal_hash, lower);
        if (type)
                goto out;

        ext = leafname;

        while ((dot = strchr(ext, '.')))
        {
                ext = dot + 1;

                type = g_hash_table_lookup(extension_hash, ext);

                if (type)
                        goto out;

                type = g_hash_table_lookup(extension_hash,
                                        lower + (ext - leafname));
                if (type)
                        goto out;
        }

        for (i = 0; i < glob_patterns->len; i++)
        {
                Pattern *p = glob_patterns->pdata[i];

                if (fnmatch(p->glob, leafname, 0) == 0 ||
                    fnmatch(p->glob, lower, 0) == 0)
                {
                        type = p->type;
                        goto out;
                }
        }

out:
        g_free(lower);

        return type;
}

/* Returns the file/dir in Choices for handling this type.
 * NULL if there isn't one. g_free() the result.
 */
static char *handler_for(MIME_type *type)
{
        char    *type_name;
        char    *open;

        type_name = g_strconcat(type->media_type, "_", type->subtype, NULL);
        open = choices_find_path_load(type_name, "MIME-types");
        g_free(type_name);

        if (!open)
                open = choices_find_path_load(type->media_type, "MIME-types");

        return open;
}

/*                      Actions for types                       */

gboolean type_open(const char *path, MIME_type *type)
{
        gchar *argv[] = {NULL, NULL, NULL};
        char            *open;
        gboolean        retval;
        struct stat     info;

        argv[1] = (char *) path;

        open = handler_for(type);
        if (!open)
                return FALSE;

        if (stat(open, &info))
        {
                report_error("stat(%s): %s", open, g_strerror(errno));
                g_free(open);
                return FALSE;
        }

        if (info.st_mode & S_IWOTH)
        {
                gchar *choices_dir;
                GList *paths;

                report_error(_("Executable '%s' is world-writeable! Refusing "
                        "to run. Please change the permissions now (this "
                        "problem may have been caused by a bug in earlier "
                        "versions of the filer).\n\n"
                        "Having (non-symlink) run actions world-writeable "
                        "means that other people who use your computer can "
                        "replace your run actions with malicious versions.\n\n"
                        "If you trust everyone who could write to these files "
                        "then you needn't worry. Otherwise, you should check, "
                        "or even just delete, all the existing run actions."),
                        open);
                choices_dir = g_path_get_dirname(open);
                paths = g_list_append(NULL, choices_dir);
                action_chmod(paths, TRUE, _("go-w (Fix security problem)"));
                g_free(choices_dir);
                g_list_free(paths);
                g_free(open);
                return TRUE;
        }

        if (S_ISDIR(info.st_mode))
                argv[0] = g_strconcat(open, "/AppRun", NULL);
        else
                argv[0] = open;

        retval = rox_spawn(home_dir, (const gchar **) argv);

        if (argv[0] != open)
                g_free(argv[0]);

        g_free(open);
        
        return retval;
}

/* Return the image for this type, loading it if needed.
 * Places to check are: (eg type="text_plain", base="text")
 * 1. Choices:MIME-icons/<type>
 * 2. Choices:MIME-icons/<base>
 * 3. Unknown type icon.
 *
 * Note: You must g_object_unref() the image afterwards.
 */
MaskedPixmap *type_to_icon(MIME_type *type)
{
        char    *path;
        char    *type_name;
        time_t  now;

        if (type == NULL)
        {
                g_object_ref(im_unknown);
                return im_unknown;
        }

        now = time(NULL);
        /* Already got an image? */
        if (type->image)
        {
                /* Yes - don't recheck too often */
                if (abs(now - type->image_time) < 2)
                {
                        g_object_ref(type->image);
                        return type->image;
                }
                g_object_unref(type->image);
                type->image = NULL;
        }

        type_name = g_strconcat(type->media_type, "_",
                                type->subtype, ".png", NULL);
        path = choices_find_path_load(type_name, "MIME-icons");
        if (!path)
        {
                strcpy(type_name + strlen(type->media_type), ".png");
                path = choices_find_path_load(type_name, "MIME-icons");
        }
        
        g_free(type_name);

        if (path)
        {
                type->image = g_fscache_lookup(pixmap_cache, path);
                g_free(path);
        }

        if (!type->image)
        {
                /* One ref from the type structure, one returned */
                type->image = im_unknown;
                g_object_ref(im_unknown);
        }

        type->image_time = now;
        
        g_object_ref(type->image);
        return type->image;
}

GdkAtom type_to_atom(MIME_type *type)
{
        char    *str;
        GdkAtom retval;
        
        g_return_val_if_fail(type != NULL, GDK_NONE);

        str = g_strconcat(type->media_type, "/", type->subtype, NULL);
        retval = gdk_atom_intern(str, FALSE);
        g_free(str);
        
        return retval;
}

static void show_shell_help(gpointer data)
{
        info_message(_("Enter a shell command which will load \"$@\" into "
                        "a suitable program. Eg:\n\n"
                        "gimp \"$@\""));
}

/* Called if the user clicks on the OK button. Returns FALSE if an error
 * was displayed instead of performing the action.
 */
static gboolean set_shell_action(GtkWidget *dialog)
{
        GtkEntry *entry;
        const guchar *command;
        gchar   *tmp, *path;
        int     error = 0, len;
        int     fd;

        entry = g_object_get_data(G_OBJECT(dialog), "shell_command");

        g_return_val_if_fail(entry != NULL, FALSE);

        command = gtk_entry_get_text(entry);
        
        if (!strchr(command, '$'))
        {
                show_shell_help(NULL);
                return FALSE;
        }

        path = get_action_save_path(dialog);
        if (!path)
                return FALSE;
                
        tmp = g_strdup_printf("#! /bin/sh\nexec %s\n", command);
        len = strlen(tmp);
        
        fd = open(path, O_CREAT | O_WRONLY, 0755);
        if (fd == -1)
                error = errno;
        else
        {
                FILE *file;

                file = fdopen(fd, "w");
                if (file)
                {
                        if (fwrite(tmp, 1, len, file) < len)
                                error = errno;
                        if (fclose(file) && error == 0)
                                error = errno;
                }
                else
                        error = errno;
        }

        if (error)
                report_error(g_strerror(error));

        g_free(tmp);
        g_free(path);

        gtk_widget_destroy(dialog);

        return TRUE;
}

static void set_action_response(GtkWidget *dialog, gint response, gpointer data)
{
        if (response == GTK_RESPONSE_OK)
                if (!set_shell_action(dialog))
                        return;
        gtk_widget_destroy(dialog);
}

/* Return the path of the file in choices that handles this type and
 * radio setting.
 * NULL if nothing is defined for it.
 */
static guchar *handler_for_radios(GObject *dialog)
{
        Radios  *radios;
        MIME_type *type;

        radios = g_object_get_data(G_OBJECT(dialog), "rox-radios");
        type = g_object_get_data(G_OBJECT(dialog), "mime_type");
        
        g_return_val_if_fail(radios != NULL, NULL);
        g_return_val_if_fail(type != NULL, NULL);
        
        switch (radios_get_value(radios))
        {
                case SET_MEDIA:
                        return choices_find_path_load(type->media_type,
                                                         "MIME-types");
                case SET_TYPE:
                {
                        gchar *tmp, *handler;
                        tmp = g_strconcat(type->media_type, "_",
                                          type->subtype, NULL);
                        handler = choices_find_path_load(tmp, "MIME-types");
                        g_free(tmp);
                        return handler;
                }
                default:
                        g_warning("Bad type");
                        return NULL;
        }
}

static void run_action_update(gpointer data)
{
        guchar *handler;
        DropBox *drop_box;
        GObject *dialog = G_OBJECT(data);

        drop_box = g_object_get_data(dialog, "rox-dropbox");

        g_return_if_fail(drop_box != NULL);

        handler = handler_for_radios(dialog);

        if (handler)
        {
                char *old = handler;

                handler = readlink_dup(old);
                if (handler)
                        g_free(old);
                else
                        handler = old;
        }

        drop_box_set_path(DROP_BOX(drop_box), handler);
        g_free(handler);
}

static void clear_run_action(GtkWidget *drop_box, GtkWidget *dialog)
{
        guchar *handler;

        handler = handler_for_radios(G_OBJECT(dialog));

        if (handler)
                remove_handler_with_confirm(handler);

        run_action_update(dialog);
}

/* Called when a URI list is dropped onto the box in the Set Run Action
 * dialog. Make sure it's an application, and make that the default
 * handler.
 */
static void drag_app_dropped(GtkWidget  *drop_box,
                             const guchar *app,
                             GtkWidget  *dialog)
{
        DirItem *item;

        item = diritem_new("");
        diritem_restat(app, item, NULL);
        if (item->flags & (ITEM_FLAG_APPDIR | ITEM_FLAG_EXEC_FILE))
        {
                guchar  *path;

                path = get_action_save_path(dialog);

                if (path)
                {
                        if (symlink(app, path))
                                delayed_error("symlink: %s",
                                                g_strerror(errno));
                        else
                                destroy_on_idle(dialog);

                        g_free(path);
                }
        }
        else
                delayed_error(
                        _("This is not a program! Give me an application "
                        "instead!"));

        diritem_free(item);
}

/* Find the current command which is used to run files of this type.
 * Returns NULL on failure. g_free() the result.
 */
static guchar *get_current_command(MIME_type *type)
{
        struct stat     info;
        char *handler, *nl, *data = NULL;
        long len;
        guchar *command = NULL;

        handler = handler_for(type);

        if (!handler)
                return NULL;            /* No current handler */

        if (stat(handler, &info))
                goto out;               /* Can't stat */

        if ((!S_ISREG(info.st_mode)) || info.st_size > 256)
                goto out;               /* Only use small regular files */
        
        if (!load_file(handler, &data, &len))
                goto out;               /* Didn't load OK */

        if (strncmp(data, "#! /bin/sh\nexec ", 16) != 0)
                goto out;               /* Not one of ours */

        nl = strchr(data + 16, '\n');
        if (!nl)
                goto out;               /* No newline! */

        command = g_strndup(data + 16, nl - data - 16);
out:
        g_free(handler);
        g_free(data);
        return command;
}

/* Find the current command which is used to run files of this type,
 * and return a textual description of it.
 * g_free() the result.
 */
gchar *describe_current_command(MIME_type *type)
{
        char *handler;
        char *desc = NULL;
        struct stat info;
        char *target;

        g_return_val_if_fail(type != NULL, NULL);

        if (type == application_executable)
                return g_strdup(_("Execute file"));

        handler = handler_for(type);

        if (!handler)
                return g_strdup(_("No run action defined"));

        target = readlink_dup(handler);
        if (target)
        {
                /* Cope with relative paths (shouldn't normally be needed) */

                if (target[0] == '/')
                {
                        g_free(handler);
                        handler = target;
                }
                else
                {
                        gchar *dir;

                        dir = g_path_get_dirname(handler);
                        g_free(handler);
                        handler = g_strconcat(dir, "/", target, NULL);
                        g_free(target);
                        g_free(dir);
                }
        }

        if (mc_stat(handler, &info) !=0 )
        {
                desc = g_strdup_printf(_("Error in handler %s: %s"), handler,
                                        g_strerror(errno));
                goto out;
        }

        if (S_ISDIR(info.st_mode))
        {
                const guchar *tmp;
                uid_t dir_uid = info.st_uid;

                tmp = make_path(handler, "AppRun");

                if (mc_lstat(tmp, &info) != 0 || info.st_uid != dir_uid
                        || !(info.st_mode & (S_IXUSR | S_IXGRP | S_IXOTH)))
                        desc = g_strdup_printf(
                                _("Invalid application %s (bad AppRun)"),
                                handler);
                /* Else, just report handler... */

                goto out;
        }

        /* It's not an application directory, and it's not a symlink... */

        if (access(handler, X_OK) != 0)
        {
                desc = g_strdup_printf(_("Non-executable %s"), handler);
                goto out;
        }

        desc = get_current_command(type);
out:
        if (!desc)
                desc = handler;
        else
                g_free(handler);

        return desc;
}

/* Display a dialog box allowing the user to set the default run action
 * for this type.
 */
void type_set_handler_dialog(MIME_type *type)
{
        guchar          *tmp;
        GtkDialog       *dialog;
        GtkWidget       *frame, *entry, *label;
        GtkWidget       *hbox;
        Radios          *radios;

        g_return_if_fail(type != NULL);

        dialog = GTK_DIALOG(gtk_dialog_new());
        gtk_dialog_set_has_separator(dialog, FALSE);
        gtk_window_set_position(GTK_WINDOW(dialog), GTK_WIN_POS_MOUSE);

        g_object_set_data(G_OBJECT(dialog), "mime_type", type);

        gtk_window_set_title(GTK_WINDOW(dialog), _("Set run action"));

        radios = radios_new(run_action_update, dialog);
        g_object_set_data(G_OBJECT(dialog), "rox-radios", radios);

        radios_add(radios,
                        _("If a handler for the specific type isn't set up, "
                          "use this as the default."), SET_MEDIA,
                        _("Set default for all `%s/<anything>'"),
                        type->media_type);
        
        radios_add(radios,
                        _("Use this application for all files with this MIME "
                          "type."), SET_TYPE,
                        _("Only for the type `%s' (%s/%s)"),
                        mime_type_comment(type),
                        type->media_type, type->subtype);

        radios_set_value(radios, SET_TYPE);

        frame = drop_box_new(_("Drop a suitable application here"));

        g_object_set_data(G_OBJECT(dialog), "rox-dropbox", frame);
        
        radios_pack(radios, GTK_BOX(dialog->vbox));
        gtk_box_pack_start(GTK_BOX(dialog->vbox), frame, TRUE, TRUE, 0);

        g_signal_connect(frame, "path_dropped",
                        G_CALLBACK(drag_app_dropped), dialog);
        g_signal_connect(frame, "clear",
                        G_CALLBACK(clear_run_action), dialog);

        hbox = gtk_hbox_new(FALSE, 4);
        gtk_box_pack_start(GTK_BOX(dialog->vbox), hbox, FALSE, TRUE, 4);
        gtk_box_pack_start(GTK_BOX(hbox), gtk_hseparator_new(), TRUE, TRUE, 0);
        gtk_box_pack_start(GTK_BOX(hbox), gtk_label_new(_("OR")),
                                                FALSE, TRUE, 0);
        gtk_box_pack_start(GTK_BOX(hbox), gtk_hseparator_new(), TRUE, TRUE, 0);

        hbox = gtk_hbox_new(FALSE, 4);
        gtk_box_pack_start(GTK_BOX(dialog->vbox), hbox, FALSE, TRUE, 0);

        label = gtk_label_new(_("Enter a shell command:")),
        gtk_misc_set_alignment(GTK_MISC(label), 0, .5);
        gtk_box_pack_start(GTK_BOX(hbox), label, TRUE, TRUE, 4);

        gtk_box_pack_start(GTK_BOX(hbox),
                        new_help_button(show_shell_help, NULL), FALSE, TRUE, 0);

        entry = gtk_entry_new();
        gtk_box_pack_start(GTK_BOX(dialog->vbox), entry, FALSE, TRUE, 0);
        gtk_widget_grab_focus(entry);
        g_object_set_data(G_OBJECT(dialog), "shell_command", entry);
        gtk_entry_set_activates_default(GTK_ENTRY(entry), TRUE);

        /* If possible, fill in the entry box with the current command */
        tmp = get_current_command(type);
        if (tmp)
        {
                gtk_entry_set_text(GTK_ENTRY(entry), tmp);
                gtk_editable_set_position(GTK_EDITABLE(entry), -1);
                g_free(tmp);
        }
        else
        {
                gtk_entry_set_text(GTK_ENTRY(entry), " \"$@\"");
                gtk_editable_set_position(GTK_EDITABLE(entry), 0);
        }

        gtk_dialog_add_buttons(dialog,
                        GTK_STOCK_CANCEL, GTK_RESPONSE_DELETE_EVENT,
                        GTK_STOCK_OK, GTK_RESPONSE_OK,
                        NULL);

        hbox = gtk_hbox_new(TRUE, 4);
        gtk_box_pack_start(GTK_BOX(dialog->vbox), hbox, FALSE, TRUE, 0);

        gtk_dialog_set_default_response(dialog, GTK_RESPONSE_OK);
        
        g_signal_connect(dialog, "response",
                        G_CALLBACK(set_action_response), NULL);

        gtk_widget_show_all(GTK_WIDGET(dialog));
}

/* path is an entry in Choices. If it's a symlink or a very small executable
 * then just get rid of it, otherwise confirm first. It it doesn't exist,
 * do nothing.
 *
 * FALSE on error (abort operation).
 */
static gboolean remove_handler_with_confirm(const guchar *path)
{
        struct stat info;

        if (lstat(path, &info) == 0)
        {
                /* A binding already exists... */
                if (S_ISREG(info.st_mode) && info.st_size > 256)
                {
                        if (!confirm(_("A run action already exists and is "
                                      "quite a big program - are you sure "
                                      "you want to delete it?"),
                                    GTK_STOCK_DELETE, NULL))
                        {
                                return FALSE;
                        }
                }
                
                if (unlink(path))
                {
                        report_error(_("Can't remove %s: %s"),
                                path, g_strerror(errno));
                        return FALSE;
                }
        }

        return TRUE;
}

/* The user wants to set a new default action for files of this type (or just
 * clear the action). Removes the current binding if possible and returns the
 * path to save the new one to. NULL means cancel. g_free() the result.
 */
static char *get_action_save_path(GtkWidget *dialog)
{
        guchar          *path = NULL;
        guchar          *type_name = NULL;
        MIME_type       *type;
        Radios          *radios;

        g_return_val_if_fail(dialog != NULL, NULL);

        type = g_object_get_data(G_OBJECT(dialog), "mime_type");
        radios = g_object_get_data(G_OBJECT(dialog), "rox-radios");

        g_return_val_if_fail(radios != NULL && type != NULL, NULL);

        if (radios_get_value(radios) == SET_MEDIA)
                type_name = g_strdup(type->media_type);
        else
                type_name = g_strconcat(type->media_type, "_",
                                type->subtype, NULL);

        path = choices_find_path_save("", PROJECT, FALSE);
        if (!path)
        {
                report_error(
                _("Choices saving is disabled by CHOICESPATH variable"));
                goto out;
        }
        g_free(path);

        path = choices_find_path_save(type_name, "MIME-types", TRUE);

        if (!remove_handler_with_confirm(path))
                null_g_free(&path);
out:
        g_free(type_name);
        return path;
}

MIME_type *mime_type_from_base_type(int base_type)
{
        switch (base_type)
        {
                case TYPE_FILE:
                        return text_plain;
                case TYPE_DIRECTORY:
                        return inode_directory;
                case TYPE_PIPE:
                        return inode_pipe;
                case TYPE_SOCKET:
                        return inode_socket;
                case TYPE_BLOCK_DEVICE:
                        return inode_block_dev;
                case TYPE_CHAR_DEVICE:
                        return inode_char_dev;
                case TYPE_DOOR:
                        return inode_door;
        }
        return inode_unknown;
}

/* Takes the st_mode field from stat() and returns the base type.
 * Should not be a symlink.
 */
int mode_to_base_type(int st_mode)
{
        if (S_ISREG(st_mode))
                return TYPE_FILE;
        else if (S_ISDIR(st_mode))
                return TYPE_DIRECTORY;
        else if (S_ISBLK(st_mode))
                return TYPE_BLOCK_DEVICE;
        else if (S_ISCHR(st_mode))
                return TYPE_CHAR_DEVICE;
        else if (S_ISFIFO(st_mode))
                return TYPE_PIPE;
        else if (S_ISSOCK(st_mode))
                return TYPE_SOCKET;
        else if (S_ISDOOR(st_mode))
                return TYPE_DOOR;

        return TYPE_ERROR;
}

/* Returns TRUE is this is something that is run by looking up its type
 * in MIME-types and, hence, can have its run action set.
 */
gboolean can_set_run_action(DirItem *item)
{
        g_return_val_if_fail(item != NULL, FALSE);

        return item->base_type == TYPE_FILE &&
                !(item->mime_type == application_executable);
}

/* To edit the MIME types, open a filer window for <Choices>/MIME-info */
static void edit_mime_types(guchar *unused)
{
        const guchar *path;

        mkdir(make_path(home_dir, ".mime"), 0700);
        path = make_path(home_dir, ".mime/packages");
        mkdir(path, 0700);
        filer_opendir(path, NULL, NULL);

        path = "/usr/local/share/mime/packages";
        if (file_exists(path))
                filer_opendir(path, NULL, NULL);

        path = "/usr/share/mime/packages";
        if (file_exists(path))
                filer_opendir(path, NULL, NULL);
}

static GList *build_type_edit(Option *none, xmlNode *node, guchar *label)
{
        GtkWidget *button, *align;

        g_return_val_if_fail(none == NULL, NULL);

        align = gtk_alignment_new(0.1, 0, 0.1, 0);
        button = gtk_button_new_with_label(_(label));
        gtk_container_add(GTK_CONTAINER(align), button);

        g_signal_connect_swapped(button, "clicked",
                        G_CALLBACK(edit_mime_types), NULL);

        return g_list_append(NULL, align);
}

/* Parse file type colours and allocate/free them as necessary */
static void alloc_type_colours(void)
{
        gboolean        success[NUM_TYPE_COLOURS];
        int             change_count = 0;       /* No. needing realloc */
        int             i;
        static gboolean allocated = FALSE;

        /* Parse colours */
        for (i = 0; i < NUM_TYPE_COLOURS; i++)
        {
                GdkColor *c = &type_colours[i];
                gushort r = c->red;
                gushort g = c->green;
                gushort b = c->blue;

                gdk_color_parse(o_type_colours[i].value, &type_colours[i]);

                if (allocated && (c->red != r || c->green != g || c->blue != b))
                        change_count++;
        }
        
        /* Free colours if they were previously allocated and
         * have changed or become unneeded.
         */
        if (allocated && (change_count || !o_display_colour_types.int_value))
        {
                gdk_colormap_free_colors(gdk_rgb_get_colormap(),
                                         type_colours, NUM_TYPE_COLOURS);
                allocated = FALSE;
        }

        /* Allocate colours, unless they are still allocated (=> they didn't
         * change) or we don't want them anymore.
         * XXX: what should be done if allocation fails?
         */
        if (!allocated && o_display_colour_types.int_value)
        {
                gdk_colormap_alloc_colors(gdk_rgb_get_colormap(),
                                type_colours, NUM_TYPE_COLOURS,
                                FALSE, TRUE, success);
                allocated = TRUE;
        }
}

/* Return a pointer to a (static) colour for this item. If colouring is
 * off, returns normal.
 */
GdkColor *type_get_colour(DirItem *item, GdkColor *normal)
{
        int type = item->base_type;

        if (!o_display_colour_types.int_value)
                return normal;

        if (item->flags & ITEM_FLAG_EXEC_FILE)
                type = TYPE_EXEC;
        else if (item->flags & ITEM_FLAG_APPDIR)
                type = TYPE_APPDIR;

        g_return_val_if_fail(type >= 0 && type < NUM_TYPE_COLOURS, normal);

        return &type_colours[type];
}

/* Process the 'Patterns' value */
static void add_pattern(MIME_type *type, const char *pattern, GHashTable *globs)
{
        if (pattern[0] == '*' && pattern[1] == '.' &&
            strpbrk(pattern + 2, "*?[") == NULL)
        {
                g_hash_table_insert(extension_hash,
                                    g_strdup(pattern + 2),
                                    type);
        }
        else if (strpbrk(pattern, "*?[") == NULL)
                g_hash_table_insert(literal_hash, g_strdup(pattern), type);
        else
                g_hash_table_insert(globs, g_strdup(pattern), type);
}

/* Load and parse this file. literal_hash and extension_hash are updated
 * directly. Other patterns are added to 'globs'.
 */
static void import_file(const gchar *file, GHashTable *globs)
{
        MIME_type *type = NULL;
        GError *error = NULL;
        gchar  *data, *line;

        if (access(file, F_OK) != 0)
                return;         /* Doesn't exist. No problem. */

        if (!g_file_get_contents(file, &data, NULL, &error))
        {
                delayed_error(_("Error loading MIME database:\n%s"),
                                error->message);
                g_error_free(error);
                return;
        }
        
        line = data;

        while (line && *line)
        {
                char *nl;

                nl = strchr(line, '\n');
                if (!nl)
                        break;
                *nl = '\0';

                if (*line != '#')
                {
                        const gchar *colon;
                        gchar *name;

                        colon = strchr(line, ':');
                        if (!colon)
                        {
                                delayed_error(_("File '%s' corrupted!"), file);
                                break;
                        }

                        name = g_strndup(line, colon - line);
                        type = get_mime_type(name, TRUE);
                        g_free(name);
                        if (!type)
                                g_warning("Invalid type in '%s'", file);

                        add_pattern(type, colon + 1, globs);
                }

                line = nl + 1;
        }

        g_free(data);
}

static void add_to_glob_patterns(gpointer key, gpointer value, gpointer unused)
{
        Pattern *pattern;

        pattern = g_new(Pattern, 1);
        pattern->glob = g_strdup((gchar *) key);
        pattern->type = (MIME_type *) value;
        pattern->len = strlen(pattern->glob);

        g_ptr_array_add(glob_patterns, pattern);
}

static gint sort_by_strlen(gconstpointer a, gconstpointer b)
{
        const Pattern *pa = *(const Pattern **) a;
        const Pattern *pb = *(const Pattern **) b;

        if (pa->len > pb->len)
                return -1;
        else if (pa->len == pb->len)
                return 0;
        return 1;
}

static char **get_xdg_data_dirs(int *n_dirs)
{
        const char *env;
        char **dirs;
        int i, n;

        env = getenv("XDG_DATA_DIRS");
        if (!env)
                env = "/usr/local/share/:/usr/share/";
        dirs = g_strsplit(env, ":", 0);
        g_return_val_if_fail(dirs != NULL, NULL);
        for (n = 0; dirs[n]; n++)
                ;
        for (i = n; i > 0; i--)
                dirs[i] = dirs[i - 1];
        env = getenv("XDG_DATA_HOME");
        if (env)
                dirs[0] = g_strdup(env);
        else
                dirs[0] = g_build_filename(g_get_home_dir(), ".local",
                                                "share", NULL);
        *n_dirs = n + 1;
        return dirs;
}

/* Clear all currently stored information and re-read everything.
 * Note: calls filer_update_all.
 */
static void load_mime_types(void)
{
        GHashTable *globs;
        char **dirs;
        int n_dirs;
        int i;

        dirs = get_xdg_data_dirs(&n_dirs);
        g_return_if_fail(dirs != NULL);

        {
                struct stat info;
                if (lstat(make_path(home_dir, ".mime"), &info) == 0 &&
                    S_ISDIR(info.st_mode))
                {
                        delayed_error(_("The ~/.mime directory has moved. "
                                "It should now be ~/.local/share/mime. You "
                                "should move it there (and make a symlink "
                                "from ~/.mime to it for older applications)."));
                }
        }

        if (!glob_patterns)
                glob_patterns = g_ptr_array_new();
        else
        {
                int i;

                for (i = glob_patterns->len - 1; i >= 0; i--)
                {
                        Pattern *p = glob_patterns->pdata[i];
                        g_free(p->glob);
                        g_free(p);
                }
                g_ptr_array_set_size(glob_patterns, 0);
        }

        if (literal_hash)
                g_hash_table_destroy(literal_hash);
        if (extension_hash)
                g_hash_table_destroy(extension_hash);
        literal_hash = g_hash_table_new_full(g_str_hash, g_str_equal,
                                                g_free, NULL);
        extension_hash = g_hash_table_new_full(g_str_hash, g_str_equal,
                                                g_free, NULL);
        globs = g_hash_table_new_full(g_str_hash, g_str_equal, g_free, NULL);

        for (i = n_dirs - 1; i >= 0; i--)
        {
                char *path;
                path = g_build_filename(dirs[i], "mime", "globs", NULL);
                import_file(path, globs);
                g_free(path);
                g_free(dirs[i]);
        }
        g_free(dirs);

        /* Turn the globs hash into a pointer array */
        g_hash_table_foreach(globs, add_to_glob_patterns, NULL);
        g_hash_table_destroy(globs);
        globs = NULL;

        if (glob_patterns->len)
                g_ptr_array_sort(glob_patterns, sort_by_strlen);

        if (g_hash_table_size(extension_hash) == 0)
        {
                delayed_error(_("The standard MIME type database "
                        "(version 0.9 or later) was not found. "
                        "The filer will probably not show the correct "
                        "types for different files. You should download and "
                        "install the 'shared-mime-info-0.9' package from "
                        "here:\n"
                "http://www.freedesktop.org/standards/shared-mime-info.html\n\n"
                "If you have already installed this package, check that the "
                "permissions allow the files to be read (check "
                "/usr/local/share/mime/globs or /usr/share/mime/globs)."));
        }

        filer_update_all();
}

/* Try to fill in 'type->comment' from this document.
 * Frees 'path'.
 */
static void get_comment(MIME_type *type, guchar *path)
{
        xmlNode *node;
        XMLwrapper *doc;
        
        doc = xml_cache_load(path);
        g_free(path);
        if (!doc)
                return;

        node = xml_get_section(doc, TYPE_NS, "comment");

        if (node)
        {
                char *val;
                g_return_if_fail(type->comment == NULL);
                val= xmlNodeListGetString(node->doc, node->xmlChildrenNode, 1);
                type->comment = g_strdup(val);
                xmlFree(val);
        }

        g_object_unref(doc);
}

/* Fill in the comment field for this MIME type.
 *
 * g_object_unref() the result.
 */
static void find_comment(MIME_type *type)
{
        guchar *path;

        if (type->comment)
        {
                g_free(type->comment);
                type->comment = NULL;
        }

        path = g_strdup_printf("%s/.mime/%s/%s.xml", home_dir,
                        type->media_type, type->subtype);
        get_comment(type, path);
        if (type->comment)
                return;

        path = g_strdup_printf("/usr/local/share/mime/%s/%s.xml",
                        type->media_type, type->subtype);
        get_comment(type, path);
        if (type->comment)
                return;

        path = g_strdup_printf("/usr/share/mime/%s/%s.xml",
                        type->media_type, type->subtype);
        get_comment(type, path);
        if (type->comment)
                return;

        type->comment = g_strdup(_("No description"));
}

const char *mime_type_comment(MIME_type *type)
{
        if (!type->comment)
                find_comment(type);

        return type->comment;
}