glib/gio/gdesktopappinfo.c

/* GIO - GLib Input, Output and Streaming Library
 * 
 * Copyright (C) 2006-2007 Red Hat, Inc.
 * Copyright © 2007 Ryan Lortie
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2 of the License, or (at your option) any later version.
 *
 * This library 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
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General
 * Public License along with this library; if not, write to the
 * Free Software Foundation, Inc., 59 Temple Place, Suite 330,
 * Boston, MA 02111-1307, USA.
 *
 * Author: Alexander Larsson <alexl@redhat.com>
 */

#include "config.h"

#include <errno.h>
#include <string.h>
#include <unistd.h>
#include <sys/wait.h>

#ifdef HAVE_CRT_EXTERNS_H
#include <crt_externs.h>
#endif

#include "gcontenttypeprivate.h"
#include "gdesktopappinfo.h"
#include "gfile.h"
#include "gioerror.h"
#include "gthemedicon.h"
#include "gfileicon.h"
#include <glib/gstdio.h>
#include "glibintl.h"
#include "giomodule-priv.h"
#include "gappinfo.h"

#include "gioalias.h"

/**
 * SECTION:gdesktopappinfo
 * @short_description: Application information from desktop files
 * @include: gio/gdesktopappinfo.h 
 * 
 * #GDesktopAppInfo is an implementation of #GAppInfo based on
 * desktop files.
 * 
 * Note that <filename>&lt;gio/gdesktopappinfo.h&gt;</filename> belongs to 
 * the UNIX-specific GIO interfaces, thus you have to use the 
 * <filename>gio-unix-2.0.pc</filename> pkg-config file when using it.
 */

#define DEFAULT_APPLICATIONS_GROUP  "Default Applications" 
#define ADDED_ASSOCIATIONS_GROUP    "Added Associations" 
#define REMOVED_ASSOCIATIONS_GROUP  "Removed Associations" 
#define MIME_CACHE_GROUP            "MIME Cache"

static void     g_desktop_app_info_iface_init         (GAppInfoIface    *iface);
static GList *  get_all_desktop_entries_for_mime_type (const char       *base_mime_type,
						       const char      **except);
static void     mime_info_cache_reload                (const char       *dir);
static gboolean g_desktop_app_info_ensure_saved       (GDesktopAppInfo  *info,
						       GError          **error);

/**
 * GDesktopAppInfo:
 * 
 * Information about an installed application from a desktop file.
 */
struct _GDesktopAppInfo
{
  GObject parent_instance;

  char *desktop_id;
  char *filename;

  char *name;
  /* FIXME: what about GenericName ? */
  char *comment;
  char *icon_name;
  GIcon *icon;
  char **only_show_in;
  char **not_show_in;
  char *try_exec;
  char *exec;
  char *binary;
  char *path;

  guint nodisplay       : 1;
  guint hidden          : 1;
  guint terminal        : 1;
  guint startup_notify  : 1;
  guint no_fuse         : 1;
  /* FIXME: what about StartupWMClass ? */
};

G_DEFINE_TYPE_WITH_CODE (GDesktopAppInfo, g_desktop_app_info, G_TYPE_OBJECT,
			 G_IMPLEMENT_INTERFACE (G_TYPE_APP_INFO,
						g_desktop_app_info_iface_init))

static gpointer
search_path_init (gpointer data)
{
  char **args = NULL;
  const char * const *data_dirs;
  const char *user_data_dir;
  int i, length, j;

  data_dirs = g_get_system_data_dirs ();
  length = g_strv_length ((char **) data_dirs);
  
  args = g_new (char *, length + 2);
  
  j = 0;
  user_data_dir = g_get_user_data_dir ();
  args[j++] = g_build_filename (user_data_dir, "applications", NULL);
  for (i = 0; i < length; i++)
    args[j++] = g_build_filename (data_dirs[i],
				  "applications", NULL);
  args[j++] = NULL;
  
  return args;
}
  
static const char * const *
get_applications_search_path (void)
{
  static GOnce once_init = G_ONCE_INIT;
  return g_once (&once_init, search_path_init, NULL);
}

static void
g_desktop_app_info_finalize (GObject *object)
{
  GDesktopAppInfo *info;

  info = G_DESKTOP_APP_INFO (object);

  g_free (info->desktop_id);
  g_free (info->filename);
  g_free (info->name);
  g_free (info->comment);
  g_free (info->icon_name);
  if (info->icon)
    g_object_unref (info->icon);
  g_strfreev (info->only_show_in);
  g_strfreev (info->not_show_in);
  g_free (info->try_exec);
  g_free (info->exec);
  g_free (info->binary);
  g_free (info->path);
  
  G_OBJECT_CLASS (g_desktop_app_info_parent_class)->finalize (object);
}

static void
g_desktop_app_info_class_init (GDesktopAppInfoClass *klass)
{
  GObjectClass *gobject_class = G_OBJECT_CLASS (klass);
  
  gobject_class->finalize = g_desktop_app_info_finalize;
}

static void
g_desktop_app_info_init (GDesktopAppInfo *local)
{
}

static char *
binary_from_exec (const char *exec)
{
  const char *p, *start;
  
  p = exec;
  while (*p == ' ')
    p++;
  start = p;
  while (*p != ' ' && *p != 0)
    p++;
  
  return g_strndup (start, p - start);
  
}

/**
 * g_desktop_app_info_new_from_keyfile:
 * @key_file: an opened #GKeyFile
 * 
 * Creates a new #GDesktopAppInfo.
 *
 * Returns: a new #GDesktopAppInfo or %NULL on error.
 *
 * Since: 2.18
 **/
GDesktopAppInfo *
g_desktop_app_info_new_from_keyfile (GKeyFile *key_file)
{
  GDesktopAppInfo *info;
  char *start_group;
  char *type;
  char *try_exec;
  
  start_group = g_key_file_get_start_group (key_file);
  if (start_group == NULL || strcmp (start_group, G_KEY_FILE_DESKTOP_GROUP) != 0)
    {
      g_free (start_group);
      return NULL;
    }
  g_free (start_group);

  type = g_key_file_get_string (key_file,
                                G_KEY_FILE_DESKTOP_GROUP,
                                G_KEY_FILE_DESKTOP_KEY_TYPE,
                                NULL);
  if (type == NULL || strcmp (type, G_KEY_FILE_DESKTOP_TYPE_APPLICATION) != 0)
    {
      g_free (type);
      return NULL;
    }
  g_free (type);

  try_exec = g_key_file_get_string (key_file,
                                    G_KEY_FILE_DESKTOP_GROUP,
                                    G_KEY_FILE_DESKTOP_KEY_TRY_EXEC,
                                    NULL);
  if (try_exec && try_exec[0] != '\0')
    {
      char *t;
      t = g_find_program_in_path (try_exec);
      if (t == NULL)
	{
	  g_free (try_exec);
	  return NULL;
	}
      g_free (t);
    }

  info = g_object_new (G_TYPE_DESKTOP_APP_INFO, NULL);
  info->filename = NULL;

  info->name = g_key_file_get_locale_string (key_file, G_KEY_FILE_DESKTOP_GROUP, G_KEY_FILE_DESKTOP_KEY_NAME, NULL, NULL);
  info->comment = g_key_file_get_locale_string (key_file, G_KEY_FILE_DESKTOP_GROUP, G_KEY_FILE_DESKTOP_KEY_COMMENT, NULL, NULL);
  info->nodisplay = g_key_file_get_boolean (key_file, G_KEY_FILE_DESKTOP_GROUP, G_KEY_FILE_DESKTOP_KEY_NO_DISPLAY, NULL) != FALSE;
  info->icon_name =  g_key_file_get_locale_string (key_file, G_KEY_FILE_DESKTOP_GROUP, G_KEY_FILE_DESKTOP_KEY_ICON, NULL, NULL);
  info->only_show_in = g_key_file_get_string_list (key_file, G_KEY_FILE_DESKTOP_GROUP, G_KEY_FILE_DESKTOP_KEY_ONLY_SHOW_IN, NULL, NULL);
  info->not_show_in = g_key_file_get_string_list (key_file, G_KEY_FILE_DESKTOP_GROUP, G_KEY_FILE_DESKTOP_KEY_NOT_SHOW_IN, NULL, NULL);
  info->try_exec = try_exec;
  info->exec = g_key_file_get_string (key_file, G_KEY_FILE_DESKTOP_GROUP, G_KEY_FILE_DESKTOP_KEY_EXEC, NULL);
  info->path = g_key_file_get_string (key_file, G_KEY_FILE_DESKTOP_GROUP, G_KEY_FILE_DESKTOP_KEY_PATH, NULL);
  info->terminal = g_key_file_get_boolean (key_file, G_KEY_FILE_DESKTOP_GROUP, G_KEY_FILE_DESKTOP_KEY_TERMINAL, NULL) != FALSE;
  info->startup_notify = g_key_file_get_boolean (key_file, G_KEY_FILE_DESKTOP_GROUP, G_KEY_FILE_DESKTOP_KEY_STARTUP_NOTIFY, NULL) != FALSE;
  info->no_fuse = g_key_file_get_boolean (key_file, G_KEY_FILE_DESKTOP_GROUP, "X-GIO-NoFuse", NULL) != FALSE;
  info->hidden = g_key_file_get_boolean (key_file, G_KEY_FILE_DESKTOP_GROUP, G_KEY_FILE_DESKTOP_KEY_HIDDEN, NULL) != FALSE;
  
  info->icon = NULL;
  if (info->icon_name)
    {
      if (g_path_is_absolute (info->icon_name))
	{
	  GFile *file;
	  
	  file = g_file_new_for_path (info->icon_name);
	  info->icon = g_file_icon_new (file);
	  g_object_unref (file);
	}
      else
        {
          char *p;

          /* Work around a common mistake in desktop files */    
          if ((p = strrchr (info->icon_name, '.')) != NULL &&
              (strcmp (p, ".png") == 0 ||
               strcmp (p, ".xpm") == 0 ||
               strcmp (p, ".svg") == 0)) 
            *p = 0;

	  info->icon = g_themed_icon_new (info->icon_name);
        }
    }
  
  if (info->exec)
    info->binary = binary_from_exec (info->exec);
  
  if (info->path && info->path[0] == '\0')
    {
      g_free (info->path);
      info->path = NULL;
    }

  return info;
}

/**
 * g_desktop_app_info_new_from_filename:
 * @filename: the path of a desktop file, in the GLib filename encoding
 * 
 * Creates a new #GDesktopAppInfo.
 *
 * Returns: a new #GDesktopAppInfo or %NULL on error.
 **/
GDesktopAppInfo *
g_desktop_app_info_new_from_filename (const char *filename)
{
  GKeyFile *key_file;
  GDesktopAppInfo *info = NULL;

  key_file = g_key_file_new ();
  
  if (g_key_file_load_from_file (key_file,
				 filename,
				 G_KEY_FILE_NONE,
				 NULL))
    {
      info = g_desktop_app_info_new_from_keyfile (key_file);
      if (info)
        info->filename = g_strdup (filename);
    }  

  g_key_file_free (key_file);

  return info;
}

/**
 * g_desktop_app_info_new:
 * @desktop_id: the desktop file id
 * 
 * Creates a new #GDesktopAppInfo based on a desktop file id. 
 *
 * A desktop file id is the basename of the desktop file, including the 
 * .desktop extension. GIO is looking for a desktop file with this name 
 * in the <filename>applications</filename> subdirectories of the XDG data
 * directories (i.e. the directories specified in the 
 * <envar>XDG_DATA_HOME</envar> and <envar>XDG_DATA_DIRS</envar> environment 
 * variables). GIO also supports the prefix-to-subdirectory mapping that is
 * described in the <ulink url="http://standards.freedesktop.org/menu-spec/latest/">Menu Spec</ulink> 
 * (i.e. a desktop id of kde-foo.desktop will match
 * <filename>/usr/share/applications/kde/foo.desktop</filename>).
 * 
 * Returns: a new #GDesktopAppInfo, or %NULL if no desktop file with that id
 */
GDesktopAppInfo *
g_desktop_app_info_new (const char *desktop_id)
{
  GDesktopAppInfo *appinfo;
  const char * const *dirs;
  char *basename;
  int i;

  dirs = get_applications_search_path ();

  basename = g_strdup (desktop_id);
  
  for (i = 0; dirs[i] != NULL; i++)
    {
      char *filename;
      char *p;

      filename = g_build_filename (dirs[i], desktop_id, NULL);
      appinfo = g_desktop_app_info_new_from_filename (filename);
      g_free (filename);
      if (appinfo != NULL)
	goto found;

      p = basename;
      while ((p = strchr (p, '-')) != NULL)
	{
	  *p = '/';
	  
	  filename = g_build_filename (dirs[i], basename, NULL);
	  appinfo = g_desktop_app_info_new_from_filename (filename);
	  g_free (filename);
	  if (appinfo != NULL)
	    goto found;
	  *p = '-';
	  p++;
	}
    }
  
  g_free (basename);
  return NULL;

 found:
  g_free (basename);
  
  appinfo->desktop_id = g_strdup (desktop_id);

  if (g_desktop_app_info_get_is_hidden (appinfo))
    {
      g_object_unref (appinfo);
      appinfo = NULL;
    }
  
  return appinfo;
}

static GAppInfo *
g_desktop_app_info_dup (GAppInfo *appinfo)
{
  GDesktopAppInfo *info = G_DESKTOP_APP_INFO (appinfo);
  GDesktopAppInfo *new_info;
  
  new_info = g_object_new (G_TYPE_DESKTOP_APP_INFO, NULL);

  new_info->filename = g_strdup (info->filename);
  new_info->desktop_id = g_strdup (info->desktop_id);
  
  new_info->name = g_strdup (info->name);
  new_info->comment = g_strdup (info->comment);
  new_info->nodisplay = info->nodisplay;
  new_info->icon_name = g_strdup (info->icon_name);
  if (info->icon)
    new_info->icon = g_object_ref (info->icon);
  new_info->only_show_in = g_strdupv (info->only_show_in);
  new_info->not_show_in = g_strdupv (info->not_show_in);
  new_info->try_exec = g_strdup (info->try_exec);
  new_info->exec = g_strdup (info->exec);
  new_info->binary = g_strdup (info->binary);
  new_info->path = g_strdup (info->path);
  new_info->hidden = info->hidden;
  new_info->terminal = info->terminal;
  new_info->startup_notify = info->startup_notify;
  
  return G_APP_INFO (new_info);
}

static gboolean
g_desktop_app_info_equal (GAppInfo *appinfo1,
			  GAppInfo *appinfo2)
{
  GDesktopAppInfo *info1 = G_DESKTOP_APP_INFO (appinfo1);
  GDesktopAppInfo *info2 = G_DESKTOP_APP_INFO (appinfo2);

  if (info1->desktop_id == NULL ||
      info2->desktop_id == NULL)
    return info1 == info2;

  return strcmp (info1->desktop_id, info2->desktop_id) == 0;
}

static const char *
g_desktop_app_info_get_id (GAppInfo *appinfo)
{
  GDesktopAppInfo *info = G_DESKTOP_APP_INFO (appinfo);

  return info->desktop_id;
}

static const char *
g_desktop_app_info_get_name (GAppInfo *appinfo)
{
  GDesktopAppInfo *info = G_DESKTOP_APP_INFO (appinfo);

  if (info->name == NULL)
    return _("Unnamed");
  return info->name;
}

/**
 * g_desktop_app_info_get_is_hidden:
 * @info: a #GDesktopAppInfo.
 *
 * A desktop file is hidden if the Hidden key in it is
 * set to True.
 *
 * Returns: %TRUE if hidden, %FALSE otherwise. 
 **/
gboolean
g_desktop_app_info_get_is_hidden (GDesktopAppInfo *info)
{
  return info->hidden;
}

static const char *
g_desktop_app_info_get_description (GAppInfo *appinfo)
{
  GDesktopAppInfo *info = G_DESKTOP_APP_INFO (appinfo);
  
  return info->comment;
}

static const char *
g_desktop_app_info_get_executable (GAppInfo *appinfo)
{
  GDesktopAppInfo *info = G_DESKTOP_APP_INFO (appinfo);
  
  return info->binary;
}

static const char *
g_desktop_app_info_get_commandline (GAppInfo *appinfo)
{
  GDesktopAppInfo *info = G_DESKTOP_APP_INFO (appinfo);
  
  return info->exec;
}

static GIcon *
g_desktop_app_info_get_icon (GAppInfo *appinfo)
{
  GDesktopAppInfo *info = G_DESKTOP_APP_INFO (appinfo);

  return info->icon;
}

static char *
expand_macro_single (char macro, char *uri)
{
  GFile *file;
  char *result = NULL;
  char *path, *name;

  file = g_file_new_for_uri (uri);
  path = g_file_get_path (file);
  g_object_unref (file);
  
  switch (macro)
    {
    case 'u':
    case 'U':	
      result = g_shell_quote (uri);
      break;
    case 'f':
    case 'F':
      if (path)
	result = g_shell_quote (path);
      break;
    case 'd':
    case 'D':
      if (path)
        {
          name = g_path_get_dirname (path);
	  result = g_shell_quote (name);
          g_free (name);
        }
      break;
    case 'n':
    case 'N':
      if (path)
        {
          name = g_path_get_basename (path);
	  result = g_shell_quote (name);
          g_free (name);
        }
      break;
    }

  g_free (path);
  
  return result;
}

static void
expand_macro (char              macro, 
              GString          *exec, 
              GDesktopAppInfo  *info, 
              GList           **uri_list)
{
  GList *uris = *uri_list;
  char *expanded;
  gboolean force_file_uri;
  char force_file_uri_macro;
  char *uri;

  g_return_if_fail (exec != NULL);

  /* On %u and %U, pass POSIX file path pointing to the URI via
   * the FUSE mount in ~/.gvfs. Note that if the FUSE daemon isn't
   * running or the URI doesn't have a POSIX file path via FUSE
   * we'll just pass the URI.
   */
  force_file_uri_macro = macro;
  force_file_uri = FALSE;
  if (!info->no_fuse)
    {
      switch (macro)
	{
	case 'u':
	  force_file_uri_macro = 'f';
	  force_file_uri = TRUE;
	  break;
	case 'U':
	  force_file_uri_macro = 'F';
	  force_file_uri = TRUE;
	  break;
	default:
	  break;
	}
    }

  switch (macro)
    {
    case 'u':
    case 'f':
    case 'd':
    case 'n':
      if (uris)
	{
	  uri = uris->data;
          if (!force_file_uri ||
	      /* Pass URI if it contains an anchor */
	      strchr (uri, '#') != NULL)
            {
              expanded = expand_macro_single (macro, uri);
            }
          else
            {
              expanded = expand_macro_single (force_file_uri_macro, uri);
              if (expanded == NULL)
                expanded = expand_macro_single (macro, uri);
            }

	  if (expanded)
	    {
	      g_string_append (exec, expanded);
	      g_free (expanded);
	    }
	  uris = uris->next;
	}

      break;

    case 'U':	
    case 'F':
    case 'D':
    case 'N':
      while (uris)
	{
	  uri = uris->data;
	  
          if (!force_file_uri ||
	      /* Pass URI if it contains an anchor */
	      strchr (uri, '#') != NULL)
            {
              expanded = expand_macro_single (macro, uri);
            }
          else
            {
              expanded = expand_macro_single (force_file_uri_macro, uri);
              if (expanded == NULL)
                expanded = expand_macro_single (macro, uri);
            }

	  if (expanded)
	    {
	      g_string_append (exec, expanded);
	      g_free (expanded);
	    }
	  
	  uris = uris->next;
	  
	  if (uris != NULL && expanded)
	    g_string_append_c (exec, ' ');
	}

      break;

    case 'i':
      if (info->icon_name)
	{
	  g_string_append (exec, "--icon ");
	  g_string_append (exec, info->icon_name);
	}
      break;

    case 'c':
      if (info->name) 
	g_string_append (exec, info->name);
      break;

    case 'k':
      if (info->filename) 
	g_string_append (exec, info->filename);
      break;

    case 'm': /* deprecated */
      break;

    case '%':
      g_string_append_c (exec, '%');
      break;
    }
  
  *uri_list = uris;
}

static gboolean
expand_application_parameters (GDesktopAppInfo   *info,
			       GList            **uris,
			       int               *argc,
			       char            ***argv,
			       GError           **error)
{
  GList *uri_list = *uris;
  const char *p = info->exec;
  GString *expanded_exec = g_string_new (NULL);
  gboolean res;
  
  if (info->exec == NULL)
    {
      g_set_error_literal (error, G_IO_ERROR, G_IO_ERROR_FAILED,
                           _("Desktop file didn't specify Exec field"));
      return FALSE;
    }
  
  while (*p)
    {
      if (p[0] == '%' && p[1] != '\0')
	{
	  expand_macro (p[1], expanded_exec, info, uris);
	  p++;
	}
      else
	g_string_append_c (expanded_exec, *p);
      
      p++;
    }
  
  /* No file substitutions */
  if (uri_list == *uris && uri_list != NULL)
    {
      /* If there is no macro default to %f. This is also what KDE does */
      g_string_append_c (expanded_exec, ' ');
      expand_macro ('f', expanded_exec, info, uris);
    }
  
  res = g_shell_parse_argv (expanded_exec->str, argc, argv, error);
  g_string_free (expanded_exec, TRUE);
  return res;
}

static gboolean
prepend_terminal_to_vector (int    *argc,
			    char ***argv)
{
#ifndef G_OS_WIN32
  char **real_argv;
  int real_argc;
  int i, j;
  char **term_argv = NULL;
  int term_argc = 0;
  char *check;
  char **the_argv;
  
  g_return_val_if_fail (argc != NULL, FALSE);
  g_return_val_if_fail (argv != NULL, FALSE);
	
  /* sanity */
  if(*argv == NULL)
    *argc = 0;
  
  the_argv = *argv;

  /* compute size if not given */
  if (*argc < 0)
    {
      for (i = 0; the_argv[i] != NULL; i++)
	;
      *argc = i;
    }
  
  term_argc = 2;
  term_argv = g_new0 (char *, 3);

  check = g_find_program_in_path ("gnome-terminal");
  if (check != NULL)
    {
      term_argv[0] = check;
      /* Note that gnome-terminal takes -x and
       * as -e in gnome-terminal is broken we use that. */
      term_argv[1] = g_strdup ("-x");
    }
  else
    {
      if (check == NULL)
	check = g_find_program_in_path ("nxterm");
      if (check == NULL)
	check = g_find_program_in_path ("color-xterm");
      if (check == NULL)
	check = g_find_program_in_path ("rxvt");
      if (check == NULL)
	check = g_find_program_in_path ("xterm");
      if (check == NULL)
	check = g_find_program_in_path ("dtterm");
      if (check == NULL)
	{
	  check = g_strdup ("xterm");
	  g_warning ("couldn't find a terminal, falling back to xterm");
	}
      term_argv[0] = check;
      term_argv[1] = g_strdup ("-e");
    }

  real_argc = term_argc + *argc;
  real_argv = g_new (char *, real_argc + 1);
  
  for (i = 0; i < term_argc; i++)
    real_argv[i] = term_argv[i];
  
  for (j = 0; j < *argc; j++, i++)
    real_argv[i] = (char *)the_argv[j];
  
  real_argv[i] = NULL;
  
  g_free (*argv);
  *argv = real_argv;
  *argc = real_argc;
  
  /* we use g_free here as we sucked all the inner strings
   * out from it into real_argv */
  g_free (term_argv);
  return TRUE;
#else
  return FALSE;
#endif /* G_OS_WIN32 */
}

/* '=' is the new '\0'.
 * DO NOT CALL unless at least one string ends with '='
 */
static gboolean
is_env (const char *a,
	const char *b)
{
  while (*a == *b)
  {
    if (*a == 0 || *b == 0)
      return FALSE;
    
    if (*a == '=')
      return TRUE;

    a++;
    b++;
  }

  return FALSE;
}

/* free with g_strfreev */
static char **
replace_env_var (char       **old_environ,
		 const char  *env_var,
		 const char  *new_value)
{
  int length, new_length;
  int index, new_index;
  char **new_environ;
  int i, new_i;

  /* do two things at once:
   *  - discover the length of the environment ('length')
   *  - find the location (if any) of the env var ('index')
   */
  index = -1;
  for (length = 0; old_environ[length]; length++)
    {
      /* if we already have it in our environment, replace */
      if (is_env (old_environ[length], env_var))
	index = length;
    }

  
  /* no current env var, no desired env value.
   * this is easy :)
   */
  if (new_value == NULL && index == -1)
    return old_environ;

  /* in all cases now, we will be using a modified environment.
   * determine its length and allocated it.
   * 
   * after this block:
   *   new_index   = location to insert, if any
   *   new_length  = length of the new array
   *   new_environ = the pointer array for the new environment
   */
  
  if (new_value == NULL && index >= 0)
    {
      /* in this case, we will be removing an entry */
      new_length = length - 1;
      new_index = -1;
    }
  else if (new_value != NULL && index < 0)
    {
      /* in this case, we will be adding an entry to the end */
      new_length = length + 1;
      new_index = length;
    }
  else
    /* in this case, we will be replacing the existing entry */
    {
      new_length = length;
      new_index = index;
    }

  new_environ = g_malloc (sizeof (char *) * (new_length + 1));
  new_environ[new_length] = NULL;

  /* now we do the copying.
   * for each entry in the new environment, we decide what to do
   */
  
  i = 0;
  for (new_i = 0; new_i < new_length; new_i++)
    {
      if (new_i == new_index)
	{
	  /* insert our new item */
	  new_environ[new_i] = g_strconcat (env_var,
					    "=",
					    new_value,
					    NULL);
	  
	  /* if we had an old entry, skip it now */
	  if (index >= 0)
	    i++;
	}
      else
	{
	  /* if this is the old DESKTOP_STARTUP_ID, skip it */
	  if (i == index)
	    i++;
	  
	  /* copy an old item */
	  new_environ[new_i] = g_strdup (old_environ[i]);
	  i++;
	}
    }

  g_strfreev (old_environ);
  
  return new_environ;
}

static GList *
uri_list_segment_to_files (GList *start,
			   GList *end)
{
  GList *res;
  GFile *file;

  res = NULL;
  while (start != NULL && start != end)
    {
      file = g_file_new_for_uri ((char *)start->data);
      res = g_list_prepend (res, file);
      start = start->next;
    }

  return g_list_reverse (res);
}

#ifdef HAVE__NSGETENVIRON
#define environ (*_NSGetEnviron())
#elif !defined(G_OS_WIN32)

/* According to the Single Unix Specification, environ is not in 
 *  * any system header, although unistd.h often declares it.
 *   */
extern char **environ;
#endif

static gboolean
g_desktop_app_info_launch_uris (GAppInfo           *appinfo,
				GList              *uris,
				GAppLaunchContext  *launch_context,
				GError            **error)
{
  GDesktopAppInfo *info = G_DESKTOP_APP_INFO (appinfo);
  gboolean completed = FALSE;
  GList *old_uris;
  GList *launched_files;
  char **envp;
  char **argv;
  int argc;
  char *display;
  char *sn_id;

  g_return_val_if_fail (appinfo != NULL, FALSE);

  argv = NULL;
  envp = NULL;
      
  do 
    {
      old_uris = uris;
      if (!expand_application_parameters (info, &uris,
					  &argc, &argv, error))
	goto out;
      
      if (info->terminal && !prepend_terminal_to_vector (&argc, &argv))
	{
	  g_set_error_literal (error, G_IO_ERROR, G_IO_ERROR_FAILED,
                               _("Unable to find terminal required for application"));
	  goto out;
	}

      sn_id = NULL;
      if (launch_context)
	{
	  launched_files = uri_list_segment_to_files (old_uris, uris);
	  
	  display = g_app_launch_context_get_display (launch_context,
						      appinfo,
						      launched_files);

	  sn_id = NULL;
	  if (info->startup_notify)
	    sn_id = g_app_launch_context_get_startup_notify_id (launch_context,
								appinfo,
								launched_files);
	  
	  if (display || sn_id)
	    {
#ifdef G_OS_WIN32
	      /* FIXME */
	      envp = g_new0 (char *, 1);
#else
	      envp = g_strdupv (environ);
#endif
	      
	      if (display)
		envp = replace_env_var (envp,
					"DISPLAY",
					display);
	      
	      if (sn_id)
		envp = replace_env_var (envp,
					"DESKTOP_STARTUP_ID",
					sn_id);
	    }

	  g_free (display);
	  
	  g_list_foreach (launched_files, (GFunc)g_object_unref, NULL);
	  g_list_free (launched_files);
	}
      
      if (!g_spawn_async (info->path,  /* working directory */
			  argv,
			  envp,
			  G_SPAWN_SEARCH_PATH /* flags */,
			  NULL /* child_setup */,
			  NULL /* data */,
			  NULL /* child_pid */,
			  error))
	{
	  if (sn_id)
	    {
	      g_app_launch_context_launch_failed (launch_context, sn_id);
	      g_free (sn_id);
	    }
	  goto out;
	}

      
      g_free (sn_id);
      
      g_strfreev (envp);
      g_strfreev (argv);
      envp = NULL;
      argv = NULL;
    }
  while (uris != NULL);

  completed = TRUE;

 out:
  g_strfreev (argv);
  g_strfreev (envp);

  return completed;
}

static gboolean
g_desktop_app_info_supports_uris (GAppInfo *appinfo)
{
  GDesktopAppInfo *info = G_DESKTOP_APP_INFO (appinfo);
 
  return info->exec && 
    ((strstr (info->exec, "%u") != NULL) ||
     (strstr (info->exec, "%U") != NULL));
}

static gboolean
g_desktop_app_info_supports_files (GAppInfo *appinfo)
{
  GDesktopAppInfo *info = G_DESKTOP_APP_INFO (appinfo);
 
  return info->exec && 
    ((strstr (info->exec, "%f") != NULL) ||
     (strstr (info->exec, "%F") != NULL));
}

static gboolean
g_desktop_app_info_launch (GAppInfo           *appinfo,
			   GList              *files,
			   GAppLaunchContext  *launch_context,
			   GError            **error)
{
  GList *uris;
  char *uri;
  gboolean res;

  uris = NULL;
  while (files)
    {
      uri = g_file_get_uri (files->data);
      uris = g_list_prepend (uris, uri);
      files = files->next;
    }
  
  uris = g_list_reverse (uris);
  
  res = g_desktop_app_info_launch_uris (appinfo, uris, launch_context, error);
  
  g_list_foreach  (uris, (GFunc)g_free, NULL);
  g_list_free (uris);
  
  return res;
}

G_LOCK_DEFINE_STATIC (g_desktop_env);
static gchar *g_desktop_env = NULL;

/**
 * g_desktop_app_info_set_desktop_env:
 * @desktop_env: a string specifying what desktop this is
 *
 * Sets the name of the desktop that the application is running in.
 * This is used by g_app_info_should_show() to evaluate the
 * <literal>OnlyShowIn</literal> and <literal>NotShowIn</literal>
 * desktop entry fields.
 *
 * The <ulink url="http://standards.freedesktop.org/menu-spec/latest/">Desktop 
 * Menu specification</ulink> recognizes the following:
 * <simplelist>
 *   <member>GNOME</member>
 *   <member>KDE</member>
 *   <member>ROX</member>
 *   <member>XFCE</member>
 *   <member>Old</member> 
 * </simplelist>
 *
 * Should be called only once; subsequent calls are ignored.
 */
void
g_desktop_app_info_set_desktop_env (const gchar *desktop_env)
{
  G_LOCK (g_desktop_env);
  if (!g_desktop_env)
    g_desktop_env = g_strdup (desktop_env);
  G_UNLOCK (g_desktop_env);
}

static gboolean
g_desktop_app_info_should_show (GAppInfo *appinfo)
{
  GDesktopAppInfo *info = G_DESKTOP_APP_INFO (appinfo);
  gboolean found;
  const gchar *desktop_env;
  int i;

  if (info->nodisplay)
    return FALSE;

  G_LOCK (g_desktop_env);
  desktop_env = g_desktop_env;
  G_UNLOCK (g_desktop_env);

  if (info->only_show_in)
    {
      if (desktop_env == NULL)
	return FALSE;
      
      found = FALSE;
      for (i = 0; info->only_show_in[i] != NULL; i++)
	{
	  if (strcmp (info->only_show_in[i], desktop_env) == 0)
	    {
	      found = TRUE;
	      break;
	    }
	}
      if (!found)
	return FALSE;
    }

  if (info->not_show_in && desktop_env)
    {
      for (i = 0; info->not_show_in[i] != NULL; i++)
	{
	  if (strcmp (info->not_show_in[i], desktop_env) == 0)
	    return FALSE;
	}
    }
  
  return TRUE;
}

typedef enum {
  APP_DIR,
  MIMETYPE_DIR
} DirType;

static char *
ensure_dir (DirType   type,
            GError  **error)
{
  char *path, *display_name;
  int errsv;

  if (type == APP_DIR)
    path = g_build_filename (g_get_user_data_dir (), "applications", NULL);
  else
    path = g_build_filename (g_get_user_data_dir (), "mime", "packages", NULL);

  errno = 0;
  if (g_mkdir_with_parents (path, 0700) == 0)
    return path;

  errsv = errno;
  display_name = g_filename_display_name (path);
  if (type == APP_DIR)
    g_set_error (error, G_IO_ERROR, g_io_error_from_errno (errsv),
                 _("Can't create user application configuration folder %s: %s"),
                 display_name, g_strerror (errsv));
  else
    g_set_error (error, G_IO_ERROR, g_io_error_from_errno (errsv),
                 _("Can't create user MIME configuration folder %s: %s"),
                 display_name, g_strerror (errsv));

  g_free (display_name);
  g_free (path);

  return NULL;
}

static gboolean
update_mimeapps_list (const char  *desktop_id, 
		      const char  *content_type, 
		      gboolean     add_as_default,
		      gboolean     add_non_default,
		      gboolean     remove, 
		      GError     **error)
{
  char *dirname, *filename;
  GKeyFile *key_file;
  gboolean load_succeeded, res;
  char **old_list, **list;
  GList *system_list, *l;
  gsize length, data_size;
  char *data;
  int i, j, k;
  char **content_types;

  /* Don't add both at start and end */
  g_assert (!(add_as_default && add_non_default));
  
  dirname = ensure_dir (APP_DIR, error);
  if (!dirname)
    return FALSE;

  filename = g_build_filename (dirname, "mimeapps.list", NULL);
  g_free (dirname);

  key_file = g_key_file_new ();
  load_succeeded = g_key_file_load_from_file (key_file, filename, G_KEY_FILE_NONE, NULL);
  if (!load_succeeded || !g_key_file_has_group (key_file, ADDED_ASSOCIATIONS_GROUP))
    {
      g_key_file_free (key_file);
      key_file = g_key_file_new ();
    }

  if (content_type)
    {
      content_types = g_new (char *, 2);
      content_types[0] = g_strdup (content_type);
      content_types[1] = NULL;
    }
  else
    {
      content_types = g_key_file_get_keys (key_file, ADDED_ASSOCIATIONS_GROUP, NULL, NULL);
    }

  for (k = 0; content_types && content_types[k]; k++)
    { 
      /* Add to the right place in the list */
  
      length = 0;
      old_list = g_key_file_get_string_list (key_file, ADDED_ASSOCIATIONS_GROUP,
					     content_types[k], &length, NULL);

      list = g_new (char *, 1 + length + 1);

      i = 0;
      if (add_as_default)
        list[i++] = g_strdup (desktop_id);
      if (old_list)
        {
          for (j = 0; old_list[j] != NULL; j++)
	    {
	      if (g_strcmp0 (old_list[j], desktop_id) != 0)
	        list[i++] = g_strdup (old_list[j]);
	      else if (add_non_default)
		{
		  /* If adding as non-default, and it's already in,
		     don't change order of desktop ids */
		  add_non_default = FALSE;
		  list[i++] = g_strdup (old_list[j]);
		}
	    }
        }
      
      if (add_non_default)
	{
	  /* We're adding as non-default, and it wasn't already in the list,
	     so we add at the end. But to avoid listing the app before the
	     current system default (thus changing the default) we have to
	     add the current list of (not yet listed) apps before it. */

	  list[i] = NULL; /* Terminate current list so we can use it */
	  system_list =  get_all_desktop_entries_for_mime_type (content_type, (const char **)list);
	  
	  list = g_renew (char *, list, 1 + length + g_list_length (system_list) + 1);
	  
	  for (l = system_list; l != NULL; l = l->next)
	    {
	      list[i++] = l->data; /* no strdup, taking ownership */
	      if (g_strcmp0 (l->data, desktop_id) == 0)
		add_non_default = FALSE;
	    }
	  g_list_free (system_list);
		  
	  if (add_non_default)
	    list[i++] = g_strdup (desktop_id);
	}
      
      list[i] = NULL;
  
      g_strfreev (old_list);

      if (list[0] == NULL || desktop_id == NULL)
        g_key_file_remove_key (key_file,
			       ADDED_ASSOCIATIONS_GROUP,
			       content_types[k],
			       NULL);
      else
        g_key_file_set_string_list (key_file,
			            ADDED_ASSOCIATIONS_GROUP,
			            content_types[k],
			            (const char * const *)list, i);
   
      g_strfreev (list);
    }
  
  if (content_type)
    {
      /* reuse the list from above */
    }
  else
    {
      g_strfreev (content_types);
      content_types = g_key_file_get_keys (key_file, REMOVED_ASSOCIATIONS_GROUP, NULL, NULL);
    }

  for (k = 0; content_types && content_types[k]; k++) 
    {
      /* Remove from removed associations group (unless remove) */
  
      length = 0;
      old_list = g_key_file_get_string_list (key_file, REMOVED_ASSOCIATIONS_GROUP,
					     content_types[k], &length, NULL);

      list = g_new (char *, 1 + length + 1);

      i = 0;
      if (remove)
        list[i++] = g_strdup (desktop_id);
      if (old_list)
        {
          for (j = 0; old_list[j] != NULL; j++)
	    {
	      if (g_strcmp0 (old_list[j], desktop_id) != 0)
	        list[i++] = g_strdup (old_list[j]);
	    }
        }
      list[i] = NULL;
  
      g_strfreev (old_list);

      if (list[0] == NULL || desktop_id == NULL)
        g_key_file_remove_key (key_file,
			       REMOVED_ASSOCIATIONS_GROUP,
			       content_types[k],
			       NULL);
      else
        g_key_file_set_string_list (key_file,
				    REMOVED_ASSOCIATIONS_GROUP,
				    content_types[k],
				    (const char * const *)list, i);

      g_strfreev (list);
    }
  
  g_strfreev (content_types);  

  data = g_key_file_to_data (key_file, &data_size, error);
  g_key_file_free (key_file);
  
  res = g_file_set_contents (filename, data, data_size, error);

  mime_info_cache_reload (NULL);
			  
  g_free (filename);
  g_free (data);
  
  return res;
}

static gboolean
g_desktop_app_info_set_as_default_for_type (GAppInfo    *appinfo,
					    const char  *content_type,
					    GError     **error)
{
  GDesktopAppInfo *info = G_DESKTOP_APP_INFO (appinfo);

  if (!g_desktop_app_info_ensure_saved (info, error))
    return FALSE;  
  
  return update_mimeapps_list (info->desktop_id, content_type, TRUE, FALSE, FALSE, error);
}

static void
update_program_done (GPid     pid,
		     gint     status,
		     gpointer data)
{
  /* Did the application exit correctly */
  if (WIFEXITED (status) &&
      WEXITSTATUS (status) == 0)
    {
      /* Here we could clean out any caches in use */
    }
}

static void
run_update_command (char *command,
		    char *subdir)
{
	char *argv[3] = {
		NULL,
		NULL,
		NULL,
	};
	GPid pid = 0;
	GError *error = NULL;

	argv[0] = command;
	argv[1] = g_build_filename (g_get_user_data_dir (), subdir, NULL);

	if (g_spawn_async ("/", argv,
			   NULL,       /* envp */
			   G_SPAWN_SEARCH_PATH |
			   G_SPAWN_STDOUT_TO_DEV_NULL |
			   G_SPAWN_STDERR_TO_DEV_NULL |
			   G_SPAWN_DO_NOT_REAP_CHILD,
			   NULL, NULL, /* No setup function */
			   &pid,
			   &error)) 
	  g_child_watch_add (pid, update_program_done, NULL);
	else
	  {
	    /* If we get an error at this point, it's quite likely the user doesn't
	     * have an installed copy of either 'update-mime-database' or
	     * 'update-desktop-database'.  I don't think we want to popup an error
	     * dialog at this point, so we just do a g_warning to give the user a
	     * chance of debugging it.
	     */
	    g_warning ("%s", error->message);
	  }
	
	g_free (argv[1]);
}

static gboolean
g_desktop_app_info_set_as_default_for_extension (GAppInfo    *appinfo,
						 const char  *extension,
						 GError     **error)
{
  char *filename, *basename, *mimetype;
  char *dirname;
  gboolean res;

  if (!g_desktop_app_info_ensure_saved (G_DESKTOP_APP_INFO (appinfo), error))
    return FALSE;  
  
  dirname = ensure_dir (MIMETYPE_DIR, error);
  if (!dirname)
    return FALSE;
  
  basename = g_strdup_printf ("user-extension-%s.xml", extension);
  filename = g_build_filename (dirname, basename, NULL);
  g_free (basename);
  g_free (dirname);

  mimetype = g_strdup_printf ("application/x-extension-%s", extension);
  
  if (!g_file_test (filename, G_FILE_TEST_EXISTS)) 
    {
      char *contents;

      contents =
        g_strdup_printf ("<?xml version=\"1.0\" encoding=\"UTF-8\"?>\n"
                         "<mime-info xmlns=\"http://www.freedesktop.org/standards/shared-mime-info\">\n"
                         " <mime-type type=\"%s\">\n"
                         "  <comment>%s document</comment>\n"
                         "  <glob pattern=\"*.%s\"/>\n"
                         " </mime-type>\n"
                         "</mime-info>\n", mimetype, extension, extension);

      g_file_set_contents (filename, contents, -1, NULL);
      g_free (contents);

      run_update_command ("update-mime-database", "mime");
    }
  g_free (filename);
  
  res = g_desktop_app_info_set_as_default_for_type (appinfo,
						    mimetype,
						    error);

  g_free (mimetype);
  
  return res;
}

static gboolean
g_desktop_app_info_add_supports_type (GAppInfo    *appinfo,
				      const char  *content_type,
				      GError     **error)
{
  GDesktopAppInfo *info = G_DESKTOP_APP_INFO (appinfo);

  if (!g_desktop_app_info_ensure_saved (G_DESKTOP_APP_INFO (info), error))
    return FALSE;  
  
  return update_mimeapps_list (info->desktop_id, content_type, FALSE, TRUE, FALSE, error);
}

static gboolean
g_desktop_app_info_can_remove_supports_type (GAppInfo *appinfo)
{
  return TRUE;
}

static gboolean
g_desktop_app_info_remove_supports_type (GAppInfo    *appinfo,
					 const char  *content_type,
					 GError     **error)
{
  GDesktopAppInfo *info = G_DESKTOP_APP_INFO (appinfo);

  if (!g_desktop_app_info_ensure_saved (G_DESKTOP_APP_INFO (info), error))
    return FALSE;
  
  return update_mimeapps_list (info->desktop_id, content_type, FALSE, FALSE, TRUE, error);
}

static gboolean
g_desktop_app_info_ensure_saved (GDesktopAppInfo  *info,
				 GError          **error)
{
  GKeyFile *key_file;
  char *dirname;
  char *filename;
  char *data, *desktop_id;
  gsize data_size;
  int fd;
  gboolean res;
  
  if (info->filename != NULL)
    return TRUE;

  /* This is only used for object created with
   * g_app_info_create_from_commandline. All other
   * object should have a filename
   */
  
  dirname = ensure_dir (APP_DIR, error);
  if (!dirname)
    return FALSE;
  
  key_file = g_key_file_new ();

  g_key_file_set_string (key_file, G_KEY_FILE_DESKTOP_GROUP,
			 "Encoding", "UTF-8");
  g_key_file_set_string (key_file, G_KEY_FILE_DESKTOP_GROUP,
			 G_KEY_FILE_DESKTOP_KEY_VERSION, "1.0");
  g_key_file_set_string (key_file, G_KEY_FILE_DESKTOP_GROUP,
			 G_KEY_FILE_DESKTOP_KEY_TYPE,
                         G_KEY_FILE_DESKTOP_TYPE_APPLICATION);
  if (info->terminal) 
    g_key_file_set_boolean (key_file, G_KEY_FILE_DESKTOP_GROUP,
			    G_KEY_FILE_DESKTOP_KEY_TERMINAL, TRUE);

  g_key_file_set_string (key_file, G_KEY_FILE_DESKTOP_GROUP,
			 G_KEY_FILE_DESKTOP_KEY_EXEC, info->exec);

  g_key_file_set_string (key_file, G_KEY_FILE_DESKTOP_GROUP,
			 G_KEY_FILE_DESKTOP_KEY_NAME, info->name);

  g_key_file_set_string (key_file, G_KEY_FILE_DESKTOP_GROUP,
			 G_KEY_FILE_DESKTOP_KEY_COMMENT, info->comment);
  
  g_key_file_set_boolean (key_file, G_KEY_FILE_DESKTOP_GROUP,
			  G_KEY_FILE_DESKTOP_KEY_NO_DISPLAY, TRUE);

  data = g_key_file_to_data (key_file, &data_size, NULL);
  g_key_file_free (key_file);

  desktop_id = g_strdup_printf ("userapp-%s-XXXXXX.desktop", info->name);
  filename = g_build_filename (dirname, desktop_id, NULL);
  g_free (desktop_id);
  g_free (dirname);
  
  fd = g_mkstemp (filename);
  if (fd == -1)
    {
      char *display_name;

      display_name = g_filename_display_name (filename);
      g_set_error (error, G_IO_ERROR, G_IO_ERROR_FAILED,
		   _("Can't create user desktop file %s"), display_name);
      g_free (display_name);
      g_free (filename);
      g_free (data);
      return FALSE;
    }

  desktop_id = g_path_get_basename (filename);

  close (fd);
  
  res = g_file_set_contents (filename, data, data_size, error);
  if (!res)
    {
      g_free (desktop_id);
      g_free (filename);
      return FALSE;
    }

  info->filename = filename;
  info->desktop_id = desktop_id;
  
  run_update_command ("update-desktop-database", "applications");
  
  return TRUE;
}

static gboolean
g_desktop_app_info_can_delete (GAppInfo *appinfo)
{
  GDesktopAppInfo *info = G_DESKTOP_APP_INFO (appinfo);

  if (info->filename)
    {
      if (strstr (info->filename, "/userapp-"))
        return g_access (info->filename, W_OK) == 0;
    }

  return FALSE;
}

static gboolean
g_desktop_app_info_delete (GAppInfo *appinfo)
{
  GDesktopAppInfo *info = G_DESKTOP_APP_INFO (appinfo);
  
  if (info->filename)
    { 
      if (g_remove (info->filename) == 0)
        {
          update_mimeapps_list (info->desktop_id, NULL, FALSE, FALSE, FALSE, NULL);

          g_free (info->filename);
          info->filename = NULL;
          g_free (info->desktop_id);
          info->desktop_id = NULL;

          return TRUE;
        }
    }

  return FALSE;
}

/**
 * g_app_info_create_from_commandline:
 * @commandline: the commandline to use
 * @application_name: the application name, or %NULL to use @commandline
 * @flags: flags that can specify details of the created #GAppInfo
 * @error: a #GError location to store the error occuring, %NULL to ignore.
 *
 * Creates a new #GAppInfo from the given information.
 *
 * Returns: new #GAppInfo for given command.
 **/
GAppInfo *
g_app_info_create_from_commandline (const char           *commandline,
				    const char           *application_name,
				    GAppInfoCreateFlags   flags,
				    GError              **error)
{
  char **split;
  char *basename;
  GDesktopAppInfo *info;

  info = g_object_new (G_TYPE_DESKTOP_APP_INFO, NULL);

  info->filename = NULL;
  info->desktop_id = NULL;
  
  info->terminal = flags & G_APP_INFO_CREATE_NEEDS_TERMINAL;
  info->startup_notify = FALSE;
  info->hidden = FALSE;
  if (flags & G_APP_INFO_CREATE_SUPPORTS_URIS)
    info->exec = g_strconcat (commandline, " %u", NULL);
  else
    info->exec = g_strconcat (commandline, " %f", NULL);
  info->nodisplay = TRUE;
  info->binary = binary_from_exec (info->exec);
  
  if (application_name)
    info->name = g_strdup (application_name);
  else
    {
      /* FIXME: this should be more robust. Maybe g_shell_parse_argv and use argv[0] */
      split = g_strsplit (commandline, " ", 2);
      basename = g_path_get_basename (split[0]);
      g_strfreev (split);
      info->name = basename;
      if (info->name == NULL)
	info->name = g_strdup ("custom");
    }
  info->comment = g_strdup_printf (_("Custom definition for %s"), info->name);
  
  return G_APP_INFO (info);
}

static void
g_desktop_app_info_iface_init (GAppInfoIface *iface)
{
  iface->dup = g_desktop_app_info_dup;
  iface->equal = g_desktop_app_info_equal;
  iface->get_id = g_desktop_app_info_get_id;
  iface->get_name = g_desktop_app_info_get_name;
  iface->get_description = g_desktop_app_info_get_description;
  iface->get_executable = g_desktop_app_info_get_executable;
  iface->get_icon = g_desktop_app_info_get_icon;
  iface->launch = g_desktop_app_info_launch;
  iface->supports_uris = g_desktop_app_info_supports_uris;
  iface->supports_files = g_desktop_app_info_supports_files;
  iface->launch_uris = g_desktop_app_info_launch_uris;
  iface->should_show = g_desktop_app_info_should_show;
  iface->set_as_default_for_type = g_desktop_app_info_set_as_default_for_type;
  iface->set_as_default_for_extension = g_desktop_app_info_set_as_default_for_extension;
  iface->add_supports_type = g_desktop_app_info_add_supports_type;
  iface->can_remove_supports_type = g_desktop_app_info_can_remove_supports_type;
  iface->remove_supports_type = g_desktop_app_info_remove_supports_type;
  iface->can_delete = g_desktop_app_info_can_delete;
  iface->do_delete = g_desktop_app_info_delete;
  iface->get_commandline = g_desktop_app_info_get_commandline;
}

static gboolean
app_info_in_list (GAppInfo *info, 
                  GList    *list)
{
  while (list != NULL)
    {
      if (g_app_info_equal (info, list->data))
	return TRUE;
      list = list->next;
    }
  return FALSE;
}


/**
 * g_app_info_get_all_for_type:
 * @content_type: the content type to find a #GAppInfo for
 * 
 * Gets a list of all #GAppInfo s for a given content type.
 *
 * Returns: #GList of #GAppInfo s for given @content_type
 *    or %NULL on error.
 **/
GList *
g_app_info_get_all_for_type (const char *content_type)
{
  GList *desktop_entries, *l;
  GList *infos;
  GDesktopAppInfo *info;

  g_return_val_if_fail (content_type != NULL, NULL);
  
  desktop_entries = get_all_desktop_entries_for_mime_type (content_type, NULL);

  infos = NULL;
  for (l = desktop_entries; l != NULL; l = l->next)
    {
      char *desktop_entry = l->data;

      info = g_desktop_app_info_new (desktop_entry);
      if (info)
	{
	  if (app_info_in_list (G_APP_INFO (info), infos))
	    g_object_unref (info);
	  else
	    infos = g_list_prepend (infos, info);
	}
      g_free (desktop_entry);
    }

  g_list_free (desktop_entries);
  
  return g_list_reverse (infos);
}

/**
 * g_app_info_reset_type_associations:
 * @content_type: a content type 
 *
 * Removes all changes to the type associations done by
 * g_app_info_set_as_default_for_type(), 
 * g_app_info_set_as_default_for_extension(), 
 * g_app_info_add_supports_type() of g_app_info_remove_supports_type().
 *
 * Since: 2.20
 */
void
g_app_info_reset_type_associations (const char *content_type)
{
  update_mimeapps_list (NULL, content_type, FALSE, FALSE, FALSE, NULL);
}

/**
 * g_app_info_get_default_for_type:
 * @content_type: the content type to find a #GAppInfo for
 * @must_support_uris: if %TRUE, the #GAppInfo is expected to
 *     support URIs
 * 
 * Gets the #GAppInfo that correspond to a given content type.
 *
 * Returns: #GAppInfo for given @content_type or %NULL on error.
 **/
GAppInfo *
g_app_info_get_default_for_type (const char *content_type,
				 gboolean    must_support_uris)
{
  GList *desktop_entries, *l;
  GAppInfo *info;

  g_return_val_if_fail (content_type != NULL, NULL);
  
  desktop_entries = get_all_desktop_entries_for_mime_type (content_type, NULL);

  info = NULL;
  for (l = desktop_entries; l != NULL; l = l->next)
    {
      char *desktop_entry = l->data;

      info = (GAppInfo *)g_desktop_app_info_new (desktop_entry);
      if (info)
	{
	  if (must_support_uris && !g_app_info_supports_uris (info))
	    {
	      g_object_unref (info);
	      info = NULL;
	    }
	  else
	    break;
	}
    }
  
  g_list_foreach  (desktop_entries, (GFunc)g_free, NULL);
  g_list_free (desktop_entries);
  
  return info;
}

/**
 * g_app_info_get_default_for_uri_scheme:
 * @uri_scheme: a string containing a URI scheme.
 *
 * Gets the default application for launching applications 
 * using this URI scheme. A URI scheme is the initial part 
 * of the URI, up to but not including the ':', e.g. "http", 
 * "ftp" or "sip".
 * 
 * Returns: #GAppInfo for given @uri_scheme or %NULL on error.
 **/
GAppInfo *
g_app_info_get_default_for_uri_scheme (const char *uri_scheme)
{
  static gsize lookup = 0;
  
  if (g_once_init_enter (&lookup))
    {
      gsize setup_value = 1;
      GDesktopAppInfoLookup *lookup_instance;
      const char *use_this;
      GIOExtensionPoint *ep;
      GIOExtension *extension;
      GList *l;

      use_this = g_getenv ("GIO_USE_URI_ASSOCIATION");
      
      /* Ensure vfs in modules loaded */
      _g_io_modules_ensure_loaded ();
      
      ep = g_io_extension_point_lookup (G_DESKTOP_APP_INFO_LOOKUP_EXTENSION_POINT_NAME);

      lookup_instance = NULL;
      if (use_this)
	{
	  extension = g_io_extension_point_get_extension_by_name (ep, use_this);
	  if (extension)
	    lookup_instance = g_object_new (g_io_extension_get_type (extension), NULL);
	}
      
      if (lookup_instance == NULL)
	{
	  for (l = g_io_extension_point_get_extensions (ep); l != NULL; l = l->next)
	    {
	      extension = l->data;
	      lookup_instance = g_object_new (g_io_extension_get_type (extension), NULL);
	      if (lookup_instance != NULL)
		break;
	    }
	}

      if (lookup_instance != NULL)
	setup_value = (gsize)lookup_instance;
      
      g_once_init_leave (&lookup, setup_value);
    }

  if (lookup == 1)
    return NULL;

  return g_desktop_app_info_lookup_get_default_for_uri_scheme (G_DESKTOP_APP_INFO_LOOKUP (lookup),
							       uri_scheme);
}


static void
get_apps_from_dir (GHashTable *apps, 
                   const char *dirname, 
                   const char *prefix)
{
  GDir *dir;
  const char *basename;
  char *filename, *subprefix, *desktop_id;
  gboolean hidden;
  GDesktopAppInfo *appinfo;
  
  dir = g_dir_open (dirname, 0, NULL);
  if (dir)
    {
      while ((basename = g_dir_read_name (dir)) != NULL)
	{
	  filename = g_build_filename (dirname, basename, NULL);
	  if (g_str_has_suffix (basename, ".desktop"))
	    {
	      desktop_id = g_strconcat (prefix, basename, NULL);

	      /* Use _extended so we catch NULLs too (hidden) */
	      if (!g_hash_table_lookup_extended (apps, desktop_id, NULL, NULL))
		{
		  appinfo = g_desktop_app_info_new_from_filename (filename);

		  if (appinfo && g_desktop_app_info_get_is_hidden (appinfo))
		    {
		      g_object_unref (appinfo);
		      appinfo = NULL;
		      hidden = TRUE;
		    }
				      
		  if (appinfo || hidden)
		    {
		      g_hash_table_insert (apps, g_strdup (desktop_id), appinfo);

		      if (appinfo)
			{
			  /* Reuse instead of strdup here */
			  appinfo->desktop_id = desktop_id;
			  desktop_id = NULL;
			}
		    }
		}
	      g_free (desktop_id);
	    }
	  else
	    {
	      if (g_file_test (filename, G_FILE_TEST_IS_DIR))
		{
		  subprefix = g_strconcat (prefix, basename, "-", NULL);
		  get_apps_from_dir (apps, filename, subprefix);
		  g_free (subprefix);
		}
	    }
	  g_free (filename);
	}
      g_dir_close (dir);
    }
}


/**
 * g_app_info_get_all:
 *
 * Gets a list of all of the applications currently registered 
 * on this system.
 * 
 * For desktop files, this includes applications that have 
 * <literal>NoDisplay=true</literal> set or are excluded from 
 * display by means of <literal>OnlyShowIn</literal> or
 * <literal>NotShowIn</literal>. See g_app_info_should_show().
 * The returned list does not include applications which have
 * the <literal>Hidden</literal> key set. 
 * 
 * Returns: a newly allocated #GList of references to #GAppInfo<!---->s.
 **/
GList *
g_app_info_get_all (void)
{
  const char * const *dirs;
  GHashTable *apps;
  GHashTableIter iter;
  gpointer value;
  int i;
  GList *infos;

  dirs = get_applications_search_path ();

  apps = g_hash_table_new_full (g_str_hash, g_str_equal,
				g_free, NULL);

  
  for (i = 0; dirs[i] != NULL; i++)
    get_apps_from_dir (apps, dirs[i], "");


  infos = NULL;
  g_hash_table_iter_init (&iter, apps);
  while (g_hash_table_iter_next (&iter, NULL, &value))
    {
      if (value)
        infos = g_list_prepend (infos, value);
    }

  g_hash_table_destroy (apps);

  return g_list_reverse (infos);
}

/* Cacheing of mimeinfo.cache and defaults.list files */

typedef struct {
  char *path;
  GHashTable *mime_info_cache_map;
  GHashTable *defaults_list_map;
  GHashTable *mimeapps_list_added_map;
  GHashTable *mimeapps_list_removed_map;
  time_t mime_info_cache_timestamp;
  time_t defaults_list_timestamp;
  time_t mimeapps_list_timestamp;
} MimeInfoCacheDir;

typedef struct {
  GList *dirs;                       /* mimeinfo.cache and defaults.list */
  GHashTable *global_defaults_cache; /* global results of defaults.list lookup and validation */
  time_t last_stat_time;
  guint should_ping_mime_monitor : 1;
} MimeInfoCache;

static MimeInfoCache *mime_info_cache = NULL;
G_LOCK_DEFINE_STATIC (mime_info_cache);

static void mime_info_cache_dir_add_desktop_entries (MimeInfoCacheDir  *dir,
						     const char        *mime_type,
						     char             **new_desktop_file_ids);

static MimeInfoCache * mime_info_cache_new (void);

static void
destroy_info_cache_value (gpointer  key, 
                          GList    *value, 
                          gpointer  data)
{
  g_list_foreach (value, (GFunc)g_free, NULL);
  g_list_free (value);
}

static void
destroy_info_cache_map (GHashTable *info_cache_map)
{
  g_hash_table_foreach (info_cache_map, (GHFunc)destroy_info_cache_value, NULL);
  g_hash_table_destroy (info_cache_map);
}

static gboolean
mime_info_cache_dir_out_of_date (MimeInfoCacheDir *dir,
				 const char       *cache_file,
				 time_t           *timestamp)
{
  struct stat buf;
  char *filename;
  
  filename = g_build_filename (dir->path, cache_file, NULL);
  
  if (g_stat (filename, &buf) < 0)
    {
      g_free (filename);
      return TRUE;
    }
  g_free (filename);

  if (buf.st_mtime != *timestamp) 
    return TRUE;
  
  return FALSE;
}

/* Call with lock held */
static gboolean
remove_all (gpointer  key,
	    gpointer  value,
	    gpointer  user_data)
{
  return TRUE;
}


static void
mime_info_cache_blow_global_cache (void)
{
  g_hash_table_foreach_remove (mime_info_cache->global_defaults_cache,
			       remove_all, NULL);
}

static void
mime_info_cache_dir_init (MimeInfoCacheDir *dir)
{
  GError *load_error;
  GKeyFile *key_file;
  gchar *filename, **mime_types;
  int i;
  struct stat buf;
  
  load_error = NULL;
  mime_types = NULL;
  
  if (dir->mime_info_cache_map != NULL &&
      !mime_info_cache_dir_out_of_date (dir, "mimeinfo.cache",
					&dir->mime_info_cache_timestamp))
    return;
  
  if (dir->mime_info_cache_map != NULL)
    destroy_info_cache_map (dir->mime_info_cache_map);
  
  dir->mime_info_cache_map = g_hash_table_new_full (g_str_hash, g_str_equal,
						    (GDestroyNotify) g_free,
						    NULL);
  
  key_file = g_key_file_new ();
  
  filename = g_build_filename (dir->path, "mimeinfo.cache", NULL);
  
  if (g_stat (filename, &buf) < 0)
    goto error;
  
  if (dir->mime_info_cache_timestamp > 0) 
    mime_info_cache->should_ping_mime_monitor = TRUE;
  
  dir->mime_info_cache_timestamp = buf.st_mtime;
  
  g_key_file_load_from_file (key_file, filename, G_KEY_FILE_NONE, &load_error);
  
  g_free (filename);
  filename = NULL;
  
  if (load_error != NULL)
    goto error;
  
  mime_types = g_key_file_get_keys (key_file, MIME_CACHE_GROUP,
				    NULL, &load_error);
  
  if (load_error != NULL)
    goto error;
  
  for (i = 0; mime_types[i] != NULL; i++)
    {
      gchar **desktop_file_ids;
      char *unaliased_type;
      desktop_file_ids = g_key_file_get_string_list (key_file,
						     MIME_CACHE_GROUP,
						     mime_types[i],
						     NULL,
						     NULL);
      
      if (desktop_file_ids == NULL)
	continue;

      unaliased_type = _g_unix_content_type_unalias (mime_types[i]);
      mime_info_cache_dir_add_desktop_entries (dir,
					       unaliased_type,
					       desktop_file_ids);
      g_free (unaliased_type);
    
      g_strfreev (desktop_file_ids);
    }
  
  g_strfreev (mime_types);
  g_key_file_free (key_file);
  
  return;
 error:
  g_free (filename);
  g_key_file_free (key_file);
  
  if (mime_types != NULL)
    g_strfreev (mime_types);
  
  if (load_error)
    g_error_free (load_error);
}

static void
mime_info_cache_dir_init_defaults_list (MimeInfoCacheDir *dir)
{
  GKeyFile *key_file;
  GError *load_error;
  gchar *filename, **mime_types;
  char *unaliased_type;
  char **desktop_file_ids;
  int i;
  struct stat buf;

  load_error = NULL;
  mime_types = NULL;

  if (dir->defaults_list_map != NULL &&
      !mime_info_cache_dir_out_of_date (dir, "defaults.list",
					&dir->defaults_list_timestamp))
    return;
  
  if (dir->defaults_list_map != NULL)
    g_hash_table_destroy (dir->defaults_list_map);
  dir->defaults_list_map = g_hash_table_new_full (g_str_hash, g_str_equal,
						  g_free, (GDestroyNotify)g_strfreev);
  

  key_file = g_key_file_new ();
  
  filename = g_build_filename (dir->path, "defaults.list", NULL);
  if (g_stat (filename, &buf) < 0)
    goto error;

  if (dir->defaults_list_timestamp > 0) 
    mime_info_cache->should_ping_mime_monitor = TRUE;

  dir->defaults_list_timestamp = buf.st_mtime;

  g_key_file_load_from_file (key_file, filename, G_KEY_FILE_NONE, &load_error);
  g_free (filename);
  filename = NULL;

  if (load_error != NULL)
    goto error;

  mime_types = g_key_file_get_keys (key_file, DEFAULT_APPLICATIONS_GROUP,
				    NULL, NULL);
  if (mime_types != NULL)
    {
      for (i = 0; mime_types[i] != NULL; i++)
	{
	  desktop_file_ids = g_key_file_get_string_list (key_file,
							 DEFAULT_APPLICATIONS_GROUP,
							 mime_types[i],
							 NULL,
							 NULL);
	  if (desktop_file_ids == NULL)
	    continue;
	  
	  unaliased_type = _g_unix_content_type_unalias (mime_types[i]);
	  g_hash_table_replace (dir->defaults_list_map,
				unaliased_type,
				desktop_file_ids);
	}
      
      g_strfreev (mime_types);
    }

  g_key_file_free (key_file);
  return;
  
 error:
  g_free (filename);
  g_key_file_free (key_file);
  
  if (mime_types != NULL)
    g_strfreev (mime_types);
  
  if (load_error)
    g_error_free (load_error);
}

static void
mime_info_cache_dir_init_mimeapps_list (MimeInfoCacheDir *dir)
{
  GKeyFile *key_file;
  GError *load_error;
  gchar *filename, **mime_types;
  char *unaliased_type;
  char **desktop_file_ids;
  int i;
  struct stat buf;

  load_error = NULL;
  mime_types = NULL;

  if (dir->mimeapps_list_added_map != NULL &&
      !mime_info_cache_dir_out_of_date (dir, "mimeapps.list",
					&dir->mimeapps_list_timestamp))
    return;
  
  if (dir->mimeapps_list_added_map != NULL)
    g_hash_table_destroy (dir->mimeapps_list_added_map);
  dir->mimeapps_list_added_map = g_hash_table_new_full (g_str_hash, g_str_equal,
							g_free, (GDestroyNotify)g_strfreev);
  
  if (dir->mimeapps_list_removed_map != NULL)
    g_hash_table_destroy (dir->mimeapps_list_removed_map);
  dir->mimeapps_list_removed_map = g_hash_table_new_full (g_str_hash, g_str_equal,
							  g_free, (GDestroyNotify)g_strfreev);

  key_file = g_key_file_new ();
  
  filename = g_build_filename (dir->path, "mimeapps.list", NULL);
  if (g_stat (filename, &buf) < 0)
    goto error;

  if (dir->mimeapps_list_timestamp > 0) 
    mime_info_cache->should_ping_mime_monitor = TRUE;

  dir->mimeapps_list_timestamp = buf.st_mtime;

  g_key_file_load_from_file (key_file, filename, G_KEY_FILE_NONE, &load_error);
  g_free (filename);
  filename = NULL;

  if (load_error != NULL)
    goto error;

  mime_types = g_key_file_get_keys (key_file, ADDED_ASSOCIATIONS_GROUP,
				    NULL, NULL);
  if (mime_types != NULL)
    {
      for (i = 0; mime_types[i] != NULL; i++)
	{
	  desktop_file_ids = g_key_file_get_string_list (key_file,
							 ADDED_ASSOCIATIONS_GROUP,
							 mime_types[i],
							 NULL,
							 NULL);
	  if (desktop_file_ids == NULL)
	    continue;
	  
	  unaliased_type = _g_unix_content_type_unalias (mime_types[i]);
	  g_hash_table_replace (dir->mimeapps_list_added_map,
				unaliased_type,
				desktop_file_ids);
	}
      
      g_strfreev (mime_types);
    }

  mime_types = g_key_file_get_keys (key_file, REMOVED_ASSOCIATIONS_GROUP,
				    NULL, NULL);
  if (mime_types != NULL)
    {
      for (i = 0; mime_types[i] != NULL; i++)
	{
	  desktop_file_ids = g_key_file_get_string_list (key_file,
							 REMOVED_ASSOCIATIONS_GROUP,
							 mime_types[i],
							 NULL,
							 NULL);
	  if (desktop_file_ids == NULL)
	    continue;
	  
	  unaliased_type = _g_unix_content_type_unalias (mime_types[i]);
	  g_hash_table_replace (dir->mimeapps_list_removed_map,
				unaliased_type,
				desktop_file_ids);
	}
      
      g_strfreev (mime_types);
    }

  g_key_file_free (key_file);
  return;
  
 error:
  g_free (filename);
  g_key_file_free (key_file);
  
  if (mime_types != NULL)
    g_strfreev (mime_types);
  
  if (load_error)
    g_error_free (load_error);
}

static MimeInfoCacheDir *
mime_info_cache_dir_new (const char *path)
{
  MimeInfoCacheDir *dir;

  dir = g_new0 (MimeInfoCacheDir, 1);
  dir->path = g_strdup (path);
  
  return dir;
}

static void
mime_info_cache_dir_free (MimeInfoCacheDir *dir)
{
  if (dir == NULL)
    return;
  
  if (dir->mime_info_cache_map != NULL)
    {
      destroy_info_cache_map (dir->mime_info_cache_map);
      dir->mime_info_cache_map = NULL;
      
  }
  
  if (dir->defaults_list_map != NULL)
    {
      g_hash_table_destroy (dir->defaults_list_map);
      dir->defaults_list_map = NULL;
    }
  
  if (dir->mimeapps_list_added_map != NULL)
    {
      g_hash_table_destroy (dir->mimeapps_list_added_map);
      dir->mimeapps_list_added_map = NULL;
    }
  
  if (dir->mimeapps_list_removed_map != NULL)
    {
      g_hash_table_destroy (dir->mimeapps_list_removed_map);
      dir->mimeapps_list_removed_map = NULL;
    }
  
  g_free (dir);
}

static void
mime_info_cache_dir_add_desktop_entries (MimeInfoCacheDir  *dir,
					 const char        *mime_type,
					 char             **new_desktop_file_ids)
{
  GList *desktop_file_ids;
  int i;
  
  desktop_file_ids = g_hash_table_lookup (dir->mime_info_cache_map,
					  mime_type);
  
  for (i = 0; new_desktop_file_ids[i] != NULL; i++)
    {
      if (!g_list_find (desktop_file_ids, new_desktop_file_ids[i]))
	desktop_file_ids = g_list_append (desktop_file_ids,
					  g_strdup (new_desktop_file_ids[i]));
    }
  
  g_hash_table_insert (dir->mime_info_cache_map, g_strdup (mime_type), desktop_file_ids);
}

static void
mime_info_cache_init_dir_lists (void)
{
  const char * const *dirs;
  int i;
  
  mime_info_cache = mime_info_cache_new ();
  
  dirs = get_applications_search_path ();
  
  for (i = 0; dirs[i] != NULL; i++)
    {
      MimeInfoCacheDir *dir;
      
      dir = mime_info_cache_dir_new (dirs[i]);
      
      if (dir != NULL)
	{
	  mime_info_cache_dir_init (dir);
	  mime_info_cache_dir_init_defaults_list (dir);
	  mime_info_cache_dir_init_mimeapps_list (dir);
	  
	  mime_info_cache->dirs = g_list_append (mime_info_cache->dirs, dir);
	}
    }
}

static void
mime_info_cache_update_dir_lists (void)
{
  GList *tmp;
  
  tmp = mime_info_cache->dirs;
  
  while (tmp != NULL)
    {
      MimeInfoCacheDir *dir = (MimeInfoCacheDir *) tmp->data;

      /* No need to do this if we had file monitors... */
      mime_info_cache_blow_global_cache ();
      mime_info_cache_dir_init (dir);
      mime_info_cache_dir_init_defaults_list (dir);
      mime_info_cache_dir_init_mimeapps_list (dir);
      
      tmp = tmp->next;
    }
}

static void
mime_info_cache_init (void)
{
  G_LOCK (mime_info_cache);
  if (mime_info_cache == NULL)
    mime_info_cache_init_dir_lists ();
  else
    {
      time_t now;
      
      time (&now);
      if (now >= mime_info_cache->last_stat_time + 10)
	{
	  mime_info_cache_update_dir_lists ();
	  mime_info_cache->last_stat_time = now;
	}
    }
  
  if (mime_info_cache->should_ping_mime_monitor)
    {
      /* g_idle_add (emit_mime_changed, NULL); */
      mime_info_cache->should_ping_mime_monitor = FALSE;
    }
  
  G_UNLOCK (mime_info_cache);
}

static MimeInfoCache *
mime_info_cache_new (void)
{
  MimeInfoCache *cache;
  
  cache = g_new0 (MimeInfoCache, 1);
  
  cache->global_defaults_cache = g_hash_table_new_full (g_str_hash, g_str_equal,
							(GDestroyNotify) g_free,
							(GDestroyNotify) g_free);
  return cache;
}

static void
mime_info_cache_free (MimeInfoCache *cache)
{
  if (cache == NULL)
    return;
  
  g_list_foreach (cache->dirs,
		  (GFunc) mime_info_cache_dir_free,
		  NULL);
  g_list_free (cache->dirs);
  g_hash_table_destroy (cache->global_defaults_cache);
  g_free (cache);
}

/**
 * mime_info_cache_reload:
 * @dir: directory path which needs reloading.
 * 
 * Reload the mime information for the @dir.
 */
static void
mime_info_cache_reload (const char *dir)
{
  /* FIXME: just reload the dir that needs reloading,
   * don't blow the whole cache
   */
  if (mime_info_cache != NULL)
    {
      G_LOCK (mime_info_cache);
      mime_info_cache_free (mime_info_cache);
      mime_info_cache = NULL;
      G_UNLOCK (mime_info_cache);
    }
}

static GList *
append_desktop_entry (GList      *list, 
                      const char *desktop_entry,
		      GList      *removed_entries)
{
  /* Add if not already in list, and valid */
  if (!g_list_find_custom (list, desktop_entry, (GCompareFunc) strcmp) &&
      !g_list_find_custom (removed_entries, desktop_entry, (GCompareFunc) strcmp))
    list = g_list_prepend (list, g_strdup (desktop_entry));
  
  return list;
}

/**
 * get_all_desktop_entries_for_mime_type:
 * @mime_type: a mime type.
 * @except: NULL or a strv list
 *
 * Returns all the desktop ids for @mime_type. The desktop files
 * are listed in an order so that default applications are listed before
 * non-default ones, and handlers for inherited mimetypes are listed
 * after the base ones.
 *
 * Optionally doesn't list the desktop ids given in the @except 
 *
 * Return value: a #GList containing the desktop ids which claim
 *    to handle @mime_type.
 */
static GList *
get_all_desktop_entries_for_mime_type (const char *base_mime_type,
				       const char **except)
{
  GList *desktop_entries, *removed_entries, *list, *dir_list, *tmp;
  MimeInfoCacheDir *dir;
  char *mime_type;
  char **mime_types;
  char **default_entries;
  char **removed_associations;
  int i, j, k;
  GPtrArray *array;
  char **anc;
  
  mime_info_cache_init ();

  /* collect all ancestors */
  mime_types = _g_unix_content_type_get_parents (base_mime_type);
  array = g_ptr_array_new ();
  for (i = 0; mime_types[i]; i++)
    g_ptr_array_add (array, mime_types[i]);
  g_free (mime_types);
  for (i = 0; i < array->len; i++)
    {
      anc = _g_unix_content_type_get_parents (g_ptr_array_index (array, i));
      for (j = 0; anc[j]; j++)
        {
          for (k = 0; k < array->len; k++)
            {
              if (strcmp (anc[j], g_ptr_array_index (array, k)) == 0)
                break;
            }
          if (k == array->len) /* not found */
            g_ptr_array_add (array, g_strdup (anc[j]));
        }
      g_strfreev (anc);
    }
  g_ptr_array_add (array, NULL);
  mime_types = (char **)g_ptr_array_free (array, FALSE);

  G_LOCK (mime_info_cache);
  
  removed_entries = NULL;
  desktop_entries = NULL;

  for (i = 0; except != NULL && except[i] != NULL; i++)
    removed_entries = g_list_prepend (removed_entries, g_strdup (except[i]));
  
  for (i = 0; mime_types[i] != NULL; i++)
    {
      mime_type = mime_types[i];

      /* Go through all apps listed as defaults */
      for (dir_list = mime_info_cache->dirs;
	   dir_list != NULL;
	   dir_list = dir_list->next)
	{
	  dir = dir_list->data;

	  /* First added associations from mimeapps.list */
	  default_entries = g_hash_table_lookup (dir->mimeapps_list_added_map, mime_type);
	  for (j = 0; default_entries != NULL && default_entries[j] != NULL; j++)
	    desktop_entries = append_desktop_entry (desktop_entries, default_entries[j], removed_entries);

	  /* Then removed associations from mimeapps.list */
	  removed_associations = g_hash_table_lookup (dir->mimeapps_list_removed_map, mime_type);
	  for (j = 0; removed_associations != NULL && removed_associations[j] != NULL; j++)
	    removed_entries = append_desktop_entry (removed_entries, removed_associations[j], NULL);

	  /* Then system defaults (or old per-user config) (using removed associations from this dir or earlier) */
	  default_entries = g_hash_table_lookup (dir->defaults_list_map, mime_type);
	  for (j = 0; default_entries != NULL && default_entries[j] != NULL; j++)
	    desktop_entries = append_desktop_entry (desktop_entries, default_entries[j], removed_entries);
	}

      /* Go through all entries that support the mimetype */
      for (dir_list = mime_info_cache->dirs;
	   dir_list != NULL;
	   dir_list = dir_list->next) 
        {
	  dir = dir_list->data;
	
	  list = g_hash_table_lookup (dir->mime_info_cache_map, mime_type);
	  for (tmp = list; tmp != NULL; tmp = tmp->next)
	    desktop_entries = append_desktop_entry (desktop_entries, tmp->data, removed_entries);
        }
    }
  
  G_UNLOCK (mime_info_cache);

  g_strfreev (mime_types);

  g_list_foreach (removed_entries, (GFunc)g_free, NULL);
  g_list_free (removed_entries);
  
  desktop_entries = g_list_reverse (desktop_entries);
  
  return desktop_entries;
}

/* GDesktopAppInfoLookup interface: */

static void g_desktop_app_info_lookup_base_init (gpointer g_class);
static void g_desktop_app_info_lookup_class_init (gpointer g_class,
						  gpointer class_data);

GType
g_desktop_app_info_lookup_get_type (void)
{
  static volatile gsize g_define_type_id__volatile = 0;

  if (g_once_init_enter (&g_define_type_id__volatile))
    {
      const GTypeInfo desktop_app_info_lookup_info =
      {
        sizeof (GDesktopAppInfoLookupIface), /* class_size */
	g_desktop_app_info_lookup_base_init,   /* base_init */
	NULL,		/* base_finalize */
	g_desktop_app_info_lookup_class_init,
	NULL,		/* class_finalize */
	NULL,		/* class_data */
	0,
	0,              /* n_preallocs */
	NULL
      };
      GType g_define_type_id =
	g_type_register_static (G_TYPE_INTERFACE, I_("GDesktopAppInfoLookup"),
				&desktop_app_info_lookup_info, 0);

      g_type_interface_add_prerequisite (g_define_type_id, G_TYPE_OBJECT);

      g_once_init_leave (&g_define_type_id__volatile, g_define_type_id);
    }

  return g_define_type_id__volatile;
}

static void
g_desktop_app_info_lookup_class_init (gpointer g_class,
				      gpointer class_data)
{
}

static void
g_desktop_app_info_lookup_base_init (gpointer g_class)
{
}

/**
 * g_desktop_app_info_lookup_get_default_for_uri_scheme:
 * @lookup: a #GDesktopAppInfoLookup
 * @uri_scheme: a string containing a URI scheme.
 *
 * Gets the default application for launching applications 
 * using this URI scheme for a particular GDesktopAppInfoLookup
 * implementation.
 *
 * The GDesktopAppInfoLookup interface and this function is used
 * to implement g_app_info_get_default_for_uri_scheme() backends
 * in a GIO module. There is no reason for applications to use it
 * directly. Applications should use g_app_info_get_default_for_uri_scheme().
 * 
 * Returns: #GAppInfo for given @uri_scheme or %NULL on error.
 */
GAppInfo *
g_desktop_app_info_lookup_get_default_for_uri_scheme (GDesktopAppInfoLookup *lookup,
						      const char            *uri_scheme)
{
  GDesktopAppInfoLookupIface *iface;
  
  g_return_val_if_fail (G_IS_DESKTOP_APP_INFO_LOOKUP (lookup), NULL);

  iface = G_DESKTOP_APP_INFO_LOOKUP_GET_IFACE (lookup);

  return (* iface->get_default_for_uri_scheme) (lookup, uri_scheme);
}

#define __G_DESKTOP_APP_INFO_C__
#include "gioaliasdef.c"