gimp/app/widgets/gimpwidgets-utils.c

/* GIMP - The GNU Image Manipulation Program
 * Copyright (C) 1995 Spencer Kimball and Peter Mattis
 *
 * gimpwidgets-utils.c
 * Copyright (C) 1999-2003 Michael Natterer <mitch@gimp.org>
 *
 * 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.
 */

#include "config.h"

#include <errno.h>
#include <fcntl.h>
#include <string.h>
#include <sys/types.h>

#ifdef HAVE_UNISTD_H
#include <unistd.h>
#endif

#include <glib/gstdio.h>

#include <glib.h>

#ifdef G_OS_WIN32
#include "libgimpbase/gimpwin32-io.h"
#endif

#include <gtk/gtk.h>

#ifdef GDK_WINDOWING_WIN32
#include <gdk/gdkwin32.h>
#endif

#ifdef GDK_WINDOWING_X11
#include <gdk/gdkx.h>
#endif

#include "libgimpbase/gimpbase.h"
#include "libgimpmath/gimpmath.h"
#include "libgimpcolor/gimpcolor.h"
#include "libgimpwidgets/gimpwidgets.h"

#include "widgets-types.h"

#include "gimperrordialog.h"
#include "gimpwidgets-utils.h"

#include "gimp-intl.h"


/**
 * gimp_menu_position:
 * @menu: a #GtkMenu widget
 * @x: pointer to horizontal position
 * @y: pointer to vertical position
 *
 * Positions a #GtkMenu so that it pops up on screen.  This function
 * takes care of the preferred popup direction (taken from the widget
 * render direction) and it handles multiple monitors representing a
 * single #GdkScreen (Xinerama).
 *
 * You should call this function with @x and @y initialized to the
 * origin of the menu. This is typically the center of the widget the
 * menu is popped up from. gimp_menu_position() will then decide if
 * and how these initial values need to be changed.
 **/
void
gimp_menu_position (GtkMenu *menu,
                    gint    *x,
                    gint    *y)
{
  GtkWidget      *widget;
  GdkScreen      *screen;
  GtkRequisition  requisition;
  GdkRectangle    rect;
  gint            monitor;

  g_return_if_fail (GTK_IS_MENU (menu));
  g_return_if_fail (x != NULL);
  g_return_if_fail (y != NULL);

  widget = GTK_WIDGET (menu);

  screen = gtk_widget_get_screen (widget);

  monitor = gdk_screen_get_monitor_at_point (screen, *x, *y);
  gdk_screen_get_monitor_geometry (screen, monitor, &rect);

  gtk_menu_set_screen (menu, screen);

  gtk_widget_size_request (widget, &requisition);

  if (gtk_widget_get_direction (widget) == GTK_TEXT_DIR_RTL)
    {
      *x -= requisition.width;
      if (*x < rect.x)
        *x += requisition.width;
    }
  else
    {
      if (*x + requisition.width > rect.x + rect.width)
        *x -= requisition.width;
    }

  if (*x < rect.x)
    *x = rect.x;

  if (*y + requisition.height > rect.y + rect.height)
    *y -= requisition.height;

  if (*y < rect.y)
    *y = rect.y;
}

/**
 * gimp_button_menu_position:
 * @button: a button widget to popup the menu from
 * @menu: the menu to position
 * @position: the preferred popup direction for the menu (left or right)
 * @x: return location for x coordinate
 * @y: return location for y coordinate
 *
 * Utility function to position a menu that pops up from a button.
 **/
void
gimp_button_menu_position (GtkWidget       *button,
                           GtkMenu         *menu,
                           GtkPositionType  position,
                           gint            *x,
                           gint            *y)
{
  GdkScreen      *screen;
  GtkRequisition  menu_requisition;
  GdkRectangle    rect;
  gint            monitor;

  g_return_if_fail (GTK_WIDGET_REALIZED (button));
  g_return_if_fail (GTK_IS_MENU (menu));
  g_return_if_fail (x != NULL);
  g_return_if_fail (y != NULL);

  if (gtk_widget_get_direction (button) == GTK_TEXT_DIR_RTL)
    {
      switch (position)
        {
        case GTK_POS_LEFT:   position = GTK_POS_RIGHT;  break;
        case GTK_POS_RIGHT:  position = GTK_POS_LEFT;   break;
        default:
          break;
        }
    }

  gdk_window_get_origin (button->window, x, y);

  gtk_widget_size_request (GTK_WIDGET (menu), &menu_requisition);

  screen = gtk_widget_get_screen (button);

  monitor = gdk_screen_get_monitor_at_point (screen, *x, *y);
  gdk_screen_get_monitor_geometry (screen, monitor, &rect);

  gtk_menu_set_screen (menu, screen);

  if (GTK_WIDGET_NO_WINDOW (button))
    *x += button->allocation.x;

  switch (position)
    {
    case GTK_POS_LEFT:
      *x -= menu_requisition.width;
      if (*x < rect.x)
        *x += menu_requisition.width + button->allocation.width;
      break;

    case GTK_POS_RIGHT:
      *x += button->allocation.width;
      if (*x + menu_requisition.width > rect.x + rect.width)
        *x -= button->allocation.width + menu_requisition.width;
      break;

    default:
      g_warning ("%s: unhandled position (%d)", G_STRFUNC, position);
      break;
    }

  if (GTK_WIDGET_NO_WINDOW (button))
    *y += button->allocation.y;

  *y += button->allocation.height / 2;

  if (*y + menu_requisition.height > rect.y + rect.height)
    *y -= menu_requisition.height;

  if (*y < rect.y)
    *y = rect.y;
}

void
gimp_table_attach_stock (GtkTable    *table,
                         gint         row,
                         const gchar *stock_id,
                         GtkWidget   *widget,
                         gint         colspan,
                         gboolean     left_align)
{
  GtkWidget *image;

  g_return_if_fail (GTK_IS_TABLE (table));
  g_return_if_fail (stock_id != NULL);
  g_return_if_fail (GTK_IS_WIDGET (widget));

  image = gtk_image_new_from_stock (stock_id, GTK_ICON_SIZE_BUTTON);
  gtk_misc_set_alignment (GTK_MISC (image), 1.0, 0.5);
  gtk_table_attach (table, image, 0, 1, row, row + 1,
                    GTK_FILL, GTK_FILL, 0, 0);
  gtk_widget_show (image);

  if (left_align)
    {
      GtkWidget *hbox = gtk_hbox_new (FALSE, 0);

      gtk_box_pack_start (GTK_BOX (hbox), widget, FALSE, FALSE, 0);
      gtk_widget_show (widget);

      widget = hbox;
    }

  gtk_table_attach (table, widget, 1, 1 + colspan, row, row + 1,
                    GTK_EXPAND | GTK_FILL, GTK_EXPAND | GTK_FILL, 0, 0);
  gtk_widget_show (widget);
}

void
gimp_enum_radio_frame_add (GtkFrame  *frame,
                           GtkWidget *widget,
                           gint       enum_value)
{
  GtkWidget *vbox;
  GList     *children;
  GList     *list;
  gint       pos;

  g_return_if_fail (GTK_IS_FRAME (frame));
  g_return_if_fail (GTK_IS_WIDGET (widget));

  vbox = gtk_bin_get_child (GTK_BIN (frame));

  g_return_if_fail (GTK_IS_VBOX (vbox));

  children = gtk_container_get_children (GTK_CONTAINER (vbox));

  for (list = children, pos = 1;
       list;
       list = g_list_next (list), pos++)
    {
      if (GTK_IS_RADIO_BUTTON (list->data) &&
          GPOINTER_TO_INT (g_object_get_data (list->data, "gimp-item-data")) ==
          enum_value)
        {
          GtkWidget *radio = list->data;
          GtkWidget *hbox;
          GtkWidget *spacer;
          gint       indicator_size;
          gint       indicator_spacing;
          gint       focus_width;
          gint       focus_padding;

          gtk_widget_style_get (radio,
                                "indicator-size",    &indicator_size,
                                "indicator-spacing", &indicator_spacing,
                                "focus-line-width",  &focus_width,
                                "focus-padding",     &focus_padding,
                                NULL);

          hbox = gtk_hbox_new (FALSE, 0);

          spacer = gtk_vbox_new (FALSE, 0);
          gtk_widget_set_size_request (spacer,
                                       indicator_size +
                                       3 * indicator_spacing +
                                       focus_width +
                                       focus_padding +
                                       GTK_CONTAINER (radio)->border_width,
                                       -1);
          gtk_box_pack_start (GTK_BOX (hbox), spacer, FALSE, FALSE, 0);
          gtk_widget_show (spacer);

          gtk_box_pack_start (GTK_BOX (hbox), widget, TRUE, TRUE, 0);
          gtk_widget_show (widget);

          g_object_set_data (G_OBJECT (radio), "set_sensitive", hbox);
          g_signal_connect (radio, "toggled",
                            G_CALLBACK (gimp_toggle_button_sensitive_update),
                            NULL);

          gtk_widget_set_sensitive (hbox,
                                    GTK_TOGGLE_BUTTON (list->data)->active);

          gtk_box_pack_start (GTK_BOX (vbox), hbox, FALSE, FALSE, 0);
          gtk_box_reorder_child (GTK_BOX (vbox), hbox, pos);
          gtk_widget_show (hbox);

          break;
        }
    }

  g_list_free (children);
}

GtkIconSize
gimp_get_icon_size (GtkWidget   *widget,
                    const gchar *stock_id,
                    GtkIconSize  max_size,
                    gint         width,
                    gint         height)
{
  GtkIconSet   *icon_set;
  GtkIconSize  *sizes;
  gint          n_sizes;
  gint          i;
  gint          width_diff  = 1024;
  gint          height_diff = 1024;
  gint          max_width;
  gint          max_height;
  GtkIconSize   icon_size = GTK_ICON_SIZE_MENU;
  GtkSettings  *settings;

  g_return_val_if_fail (GTK_IS_WIDGET (widget), icon_size);
  g_return_val_if_fail (stock_id != NULL, icon_size);
  g_return_val_if_fail (width > 0, icon_size);
  g_return_val_if_fail (height > 0, icon_size);

  icon_set = gtk_style_lookup_icon_set (widget->style, stock_id);

  if (! icon_set)
    return GTK_ICON_SIZE_INVALID;

  settings = gtk_widget_get_settings (widget);

  if (! gtk_icon_size_lookup_for_settings (settings, max_size,
                                           &max_width, &max_height))
    {
      max_width  = 1024;
      max_height = 1024;
    }

  gtk_icon_set_get_sizes (icon_set, &sizes, &n_sizes);

  for (i = 0; i < n_sizes; i++)
    {
      gint icon_width;
      gint icon_height;

      if (gtk_icon_size_lookup_for_settings (settings, sizes[i],
                                             &icon_width, &icon_height))
        {
          if (icon_width  <= width      &&
              icon_height <= height     &&
              icon_width  <= max_width  &&
              icon_height <= max_height &&
              ((width  - icon_width)  < width_diff ||
               (height - icon_height) < height_diff))
            {
              width_diff  = width  - icon_width;
              height_diff = height - icon_height;

              icon_size = sizes[i];
            }
        }
    }

  g_free (sizes);

  return icon_size;
}

const gchar *
gimp_get_mod_name_shift (void)
{
  static gchar *mod_name_shift = NULL;

  if (! mod_name_shift)
    {
      GtkAccelLabelClass *accel_label_class;

      accel_label_class = g_type_class_ref (GTK_TYPE_ACCEL_LABEL);
      mod_name_shift = g_strdup (accel_label_class->mod_name_shift);
      g_type_class_unref (accel_label_class);
    }

  return (const gchar *) mod_name_shift;
}

const gchar *
gimp_get_mod_name_control (void)
{
  static gchar *mod_name_control = NULL;

  if (! mod_name_control)
    {
      GtkAccelLabelClass *accel_label_class;

      accel_label_class = g_type_class_ref (GTK_TYPE_ACCEL_LABEL);
      mod_name_control = g_strdup (accel_label_class->mod_name_control);
      g_type_class_unref (accel_label_class);
    }

  return (const gchar *) mod_name_control;
}

const gchar *
gimp_get_mod_name_alt (void)
{
  static gchar *mod_name_alt = NULL;

  if (! mod_name_alt)
    {
      GtkAccelLabelClass *accel_label_class;

      accel_label_class = g_type_class_ref (GTK_TYPE_ACCEL_LABEL);
      mod_name_alt = g_strdup (accel_label_class->mod_name_alt);
      g_type_class_unref (accel_label_class);
    }

  return (const gchar *) mod_name_alt;
}

const gchar *
gimp_get_mod_separator (void)
{
  static gchar *mod_separator = NULL;

  if (! mod_separator)
    {
      GtkAccelLabelClass *accel_label_class;

      accel_label_class = g_type_class_ref (GTK_TYPE_ACCEL_LABEL);
      mod_separator = g_strdup (accel_label_class->mod_separator);
      g_type_class_unref (accel_label_class);
    }

  return (const gchar *) mod_separator;
}

const gchar *
gimp_get_mod_string (GdkModifierType modifiers)
{
  static struct
  {
    GdkModifierType  modifiers;
    gchar           *name;
  }
  modifier_strings[] =
  {
    { GDK_SHIFT_MASK,                                      NULL },
    { GDK_CONTROL_MASK,                                    NULL },
    { GDK_MOD1_MASK,                                       NULL },
    { GDK_SHIFT_MASK   | GDK_CONTROL_MASK,                 NULL },
    { GDK_SHIFT_MASK   | GDK_MOD1_MASK,                    NULL },
    { GDK_CONTROL_MASK | GDK_MOD1_MASK,                    NULL },
    { GDK_SHIFT_MASK   | GDK_CONTROL_MASK | GDK_MOD1_MASK, NULL }
  };

  gint i;

  for (i = 0; i < G_N_ELEMENTS (modifier_strings); i++)
    {
      if (modifiers == modifier_strings[i].modifiers)
        {
          if (! modifier_strings[i].name)
            {
              GString *str = g_string_new (NULL);

              if (modifiers & GDK_SHIFT_MASK)
                {
                  g_string_append (str, gimp_get_mod_name_shift ());
                }

              if (modifiers & GDK_CONTROL_MASK)
                {
                  if (str->len)
                    g_string_append (str, gimp_get_mod_separator ());

                  g_string_append (str, gimp_get_mod_name_control ());
                }

              if (modifiers & GDK_MOD1_MASK)
                {
                  if (str->len)
                    g_string_append (str, gimp_get_mod_separator ());

                  g_string_append (str, gimp_get_mod_name_alt ());
                }

              modifier_strings[i].name = g_string_free (str, FALSE);
            }

          return modifier_strings[i].name;
        }
    }

  return NULL;
}

#define BUF_SIZE 100
/**
 * gimp_suggest_modifiers:
 * @message: initial text for the message
 * @modifiers: bit mask of modifiers that should be suggested
 * @shift_format: optional format string for the Shift modifier
 * @control_format: optional format string for the Ctrl modifier
 * @alt_format: optional format string for the Alt modifier
 *
 * Utility function to build a message suggesting to use some
 * modifiers for performing different actions (only Shift, Ctrl and
 * Alt are currently supported).  If some of these modifiers are
 * already active, they will not be suggested.  The optional format
 * strings #shift_format, #control_format and #alt_format may be used
 * to describe what the modifier will do.  They must contain a single
 * '%%s' which will be replaced by the name of the modifier.  They
 * can also be %NULL if the modifier name should be left alone.
 *
 * Return value: a newly allocated string containing the message.
 **/
gchar *
gimp_suggest_modifiers (const gchar     *message,
                        GdkModifierType  modifiers,
                        const gchar     *shift_format,
                        const gchar     *control_format,
                        const gchar     *alt_format)
{
  gchar     msg_buf[3][BUF_SIZE];
  gint      num_msgs = 0;
  gboolean  try      = FALSE;

  if (modifiers & GDK_SHIFT_MASK)
    {
      if (shift_format && *shift_format)
        {
          g_snprintf (msg_buf[num_msgs], BUF_SIZE, shift_format,
                      gimp_get_mod_name_shift ());
        }
      else
        {
          g_strlcpy (msg_buf[num_msgs], gimp_get_mod_name_shift (), BUF_SIZE);
          try = TRUE;
        }

      num_msgs++;
    }

  if (modifiers & GDK_CONTROL_MASK)
    {
      if (control_format && *control_format)
        {
          g_snprintf (msg_buf[num_msgs], BUF_SIZE, control_format,
                      gimp_get_mod_name_control ());
        }
      else
        {
          g_strlcpy (msg_buf[num_msgs], gimp_get_mod_name_control (), BUF_SIZE);
          try = TRUE;
        }

      num_msgs++;
    }

  if (modifiers & GDK_MOD1_MASK)
    {
      if (alt_format && *alt_format)
        {
          g_snprintf (msg_buf[num_msgs], BUF_SIZE, alt_format,
                      gimp_get_mod_name_alt ());
        }
      else
        {
          g_strlcpy (msg_buf[num_msgs], gimp_get_mod_name_alt (), BUF_SIZE);
          try = TRUE;
        }

      num_msgs++;
    }

  /* This convoluted way to build the message using multiple format strings
   * tries to make the messages easier to translate to other languages.
   */

  switch (num_msgs)
    {
    case 1:
      return g_strdup_printf (try ? _("%s (try %s)") : _("%s (%s)"),
                              message, msg_buf[0]);

    case 2:
      return g_strdup_printf (_("%s (try %s, %s)"),
                              message, msg_buf[0], msg_buf[1]);

    case 3:
      return g_strdup_printf (_("%s (try %s, %s, %s)"),
                              message, msg_buf[0], msg_buf[1], msg_buf[2]);
    }

  return g_strdup (message);
}
#undef BUF_SIZE

/**
 * gimp_get_screen_resolution:
 * @screen: a #GdkScreen or %NULL
 * @xres: returns the horizontal screen resolution (in dpi)
 * @yres: returns the vertical screen resolution (in dpi)
 *
 * Retrieves the screen resolution from GDK. If @screen is %NULL, the
 * default screen is used.
 **/
void
gimp_get_screen_resolution (GdkScreen *screen,
                            gdouble   *xres,
                            gdouble   *yres)
{
  gint    width, height;
  gint    width_mm, height_mm;
  gdouble x = 0.0;
  gdouble y = 0.0;

  g_return_if_fail (screen == NULL || GDK_IS_SCREEN (screen));
  g_return_if_fail (xres != NULL);
  g_return_if_fail (yres != NULL);

  if (!screen)
    screen = gdk_screen_get_default ();

  width  = gdk_screen_get_width (screen);
  height = gdk_screen_get_height (screen);

  width_mm  = gdk_screen_get_width_mm (screen);
  height_mm = gdk_screen_get_height_mm (screen);

  /*
   * From xdpyinfo.c:
   *
   * there are 2.54 centimeters to an inch; so there are 25.4 millimeters.
   *
   *     dpi = N pixels / (M millimeters / (25.4 millimeters / 1 inch))
   *         = N pixels / (M inch / 25.4)
   *         = N * 25.4 pixels / M inch
   */

  if (width_mm > 0 && height_mm > 0)
    {
      x = (width  * 25.4) / (gdouble) width_mm;
      y = (height * 25.4) / (gdouble) height_mm;
    }

  if (x < GIMP_MIN_RESOLUTION || x > GIMP_MAX_RESOLUTION ||
      y < GIMP_MIN_RESOLUTION || y > GIMP_MAX_RESOLUTION)
    {
      g_warning ("GDK returned bogus values for the screen resolution, "
                 "using 96 dpi instead.");

      x = 96.0;
      y = 96.0;
    }

  /*  round the value to full integers to give more pleasant results  */
  *xres = ROUND (x);
  *yres = ROUND (y);
}


/**
 * gimp_rgb_get_gdk_color:
 * @rgb: the source color as #GimpRGB
 * @gdk_color: pointer to a #GdkColor
 *
 * Initializes @gdk_color from a #GimpRGB. This function does not
 * allocate the color for you. Depending on how you want to use it,
 * you may have to call gdk_colormap_alloc_color().
 **/
void
gimp_rgb_get_gdk_color (const GimpRGB *rgb,
                        GdkColor      *gdk_color)
{
  guchar r, g, b;

  g_return_if_fail (rgb != NULL);
  g_return_if_fail (gdk_color != NULL);

  gimp_rgb_get_uchar (rgb, &r, &g, &b);

  gdk_color->red   = (r << 8) | r;
  gdk_color->green = (g << 8) | g;
  gdk_color->blue  = (b << 8) | b;
}

/**
 * gimp_rgb_set_gdk_color:
 * @rgb: a #GimpRGB that is to be set
 * @gdk_color: pointer to the source #GdkColor
 *
 * Initializes @rgb from a #GdkColor. This function does not touch
 * the alpha value of @rgb.
 **/
void
gimp_rgb_set_gdk_color (GimpRGB        *rgb,
                        const GdkColor *gdk_color)
{
  guchar r, g, b;

  g_return_if_fail (rgb != NULL);
  g_return_if_fail (gdk_color != NULL);

  r = gdk_color->red   >> 8;
  g = gdk_color->green >> 8;
  b = gdk_color->blue  >> 8;

  gimp_rgb_set_uchar (rgb, r, g, b);
}

void
gimp_window_set_hint (GtkWindow      *window,
                      GimpWindowHint  hint)
{
  g_return_if_fail (GTK_IS_WINDOW (window));

  switch (hint)
    {
    case GIMP_WINDOW_HINT_NORMAL:
      gtk_window_set_type_hint (window, GDK_WINDOW_TYPE_HINT_NORMAL);
      break;

    case GIMP_WINDOW_HINT_UTILITY:
      gtk_window_set_type_hint (window, GDK_WINDOW_TYPE_HINT_UTILITY);
      break;

    case GIMP_WINDOW_HINT_KEEP_ABOVE:
      gtk_window_set_keep_above (window, TRUE);
      break;
    }
}

/**
 * gimp_window_get_native:
 * @window: a #GtkWindow
 *
 * This function is used to pass a window handle to plug-ins so that
 * they can set their dialog windows transient to the parent window.
 *
 * Return value: a native window handle of the window's #GdkWindow or 0
 *               if the window isn't realized yet
 */
GdkNativeWindow
gimp_window_get_native (GtkWindow *window)
{
  g_return_val_if_fail (GTK_IS_WINDOW (window), 0);

#ifdef GDK_NATIVE_WINDOW_POINTER
#ifdef __GNUC__
#warning gimp_window_get_native() unimplementable for the target windowing system
#endif
  return (GdkNativeWindow)0;
#endif

#ifdef GDK_WINDOWING_WIN32
  if (window && GTK_WIDGET_REALIZED (window))
    return (GdkNativeWindow)GDK_WINDOW_HWND (GTK_WIDGET (window)->window);
#endif

#ifdef GDK_WINDOWING_X11
  if (window && GTK_WIDGET_REALIZED (window))
    return GDK_WINDOW_XID (GTK_WIDGET (window)->window);
#endif

  return (GdkNativeWindow)0;
}

static void
gimp_window_transient_realized (GtkWidget *window,
                                GdkWindow *parent)
{
  if (GTK_WIDGET_REALIZED (window))
    gdk_window_set_transient_for (window->window, parent);
}

/* similar to what we have in libgimp/gimpui.c */
void
gimp_window_set_transient_for (GtkWindow *window,
                               guint32    parent_ID)
{
  /* Cross-process transient-for is broken in gdk/win32 <= 2.10.6. It
   * causes hangs, at least when used as by the gimp and script-fu
   * processes. In some newer GTK+ version it will be fixed to be a
   * no-op. If it eventually is fixed to actually work, change this to
   * a run-time check of GTK+ version. Remember to change also the
   * function with the same name in libgimp/gimpui.c
   */
#ifndef GDK_WINDOWING_WIN32
  GdkWindow *parent;

  parent = gdk_window_foreign_new_for_display (gdk_display_get_default (),
                                               parent_ID);

  if (! parent)
    return;

  if (GTK_WIDGET_REALIZED (window))
    gdk_window_set_transient_for (GTK_WIDGET (window)->window, parent);

  g_signal_connect_object (window, "realize",
                           G_CALLBACK (gimp_window_transient_realized),
                           parent, 0);

  g_object_unref (parent);
#endif
}

gboolean
gimp_text_buffer_load (GtkTextBuffer  *buffer,
                       const gchar    *filename,
                       GError        **error)
{
  FILE        *file;
  gchar        buf[2048];
  gint         remaining = 0;
  GtkTextIter  iter;

  g_return_val_if_fail (GTK_IS_TEXT_BUFFER (buffer), FALSE);
  g_return_val_if_fail (filename != NULL, FALSE);
  g_return_val_if_fail (error == NULL || *error == NULL, FALSE);

  file = g_fopen (filename, "r");

  if (! file)
    {
      g_set_error (error, G_FILE_ERROR, g_file_error_from_errno (errno),
                   g_strerror (errno));
      return FALSE;
    }

  gtk_text_buffer_set_text (buffer, "", 0);
  gtk_text_buffer_get_iter_at_offset (buffer, &iter, 0);

  while (! feof (file))
    {
      const char *leftover;
      gint        count;
      gint        to_read = sizeof (buf) - remaining - 1;

      count = fread (buf + remaining, 1, to_read, file);
      buf[count + remaining] = '\0';

      g_utf8_validate (buf, count + remaining, &leftover);

      gtk_text_buffer_insert (buffer, &iter, buf, leftover - buf);
      gtk_text_buffer_get_iter_at_offset (buffer, &iter, -1);

      remaining = (buf + remaining + count) - leftover;
      g_memmove (buf, leftover, remaining);

      if (remaining > 6 || count < to_read)
        break;
    }

  if (remaining)
    g_message (_("Invalid UTF-8 data in file '%s'."),
               gimp_filename_to_utf8 (filename));

  fclose (file);

  return TRUE;
}

gboolean
gimp_text_buffer_save (GtkTextBuffer  *buffer,
                       const gchar    *filename,
                       gboolean        selection_only,
                       GError        **error)
{
  GtkTextIter  start_iter;
  GtkTextIter  end_iter;
  gint         fd;
  gchar       *text_contents;

  g_return_val_if_fail (GTK_IS_TEXT_BUFFER (buffer), FALSE);
  g_return_val_if_fail (filename != NULL, FALSE);
  g_return_val_if_fail (error == NULL || *error == NULL, FALSE);

  fd = g_open (filename, O_WRONLY | O_CREAT | O_APPEND, S_IRUSR | S_IWUSR);

  if (fd == -1)
    {
      g_set_error (error, G_FILE_ERROR, g_file_error_from_errno (errno),
                   g_strerror (errno));
      return FALSE;
    }

  if (selection_only)
    gtk_text_buffer_get_selection_bounds (buffer, &start_iter, &end_iter);
  else
    gtk_text_buffer_get_bounds (buffer, &start_iter, &end_iter);

  text_contents = gtk_text_buffer_get_text (buffer,
                                            &start_iter, &end_iter, TRUE);

  if (text_contents)
    {
      gint text_length = strlen (text_contents);

      if (text_length > 0)
        {
          gint bytes_written;

          bytes_written = write (fd, text_contents, text_length);

          if (bytes_written != text_length)
            {
              g_free (text_contents);
              close (fd);
              g_set_error (error, G_FILE_ERROR, g_file_error_from_errno (errno),
                           g_strerror (errno));
              return FALSE;
            }
        }

      g_free (text_contents);
    }

  close (fd);

  return TRUE;
}

void
gimp_toggle_button_set_visible (GtkToggleButton *toggle,
                                GtkWidget       *widget)
{
  g_return_if_fail (GTK_IS_TOGGLE_BUTTON (toggle));
  g_return_if_fail (GTK_IS_WIDGET (widget));

  if (gtk_toggle_button_get_active (toggle))
    gtk_widget_show (widget);
  else
    gtk_widget_hide (widget);
}

static gboolean
gimp_widget_accel_find_func (GtkAccelKey *key,
                             GClosure    *closure,
                             gpointer     data)
{
  return (GClosure *) data == closure;
}

static void
gimp_widget_accel_changed (GtkAccelGroup   *accel_group,
                           guint            unused1,
                           GdkModifierType  unused2,
                           GClosure        *accel_closure,
                           GtkWidget       *widget)
{
  GClosure *widget_closure;

  widget_closure = g_object_get_data (G_OBJECT (widget), "gimp-accel-closure");

  if (accel_closure == widget_closure)
    {
      GtkAction   *action;
      GtkAccelKey *accel_key;
      gchar       *tooltip;
      const gchar *help_id;

      action = g_object_get_data (G_OBJECT (widget), "gimp-accel-action");

      g_object_get (action, "tooltip", &tooltip, NULL);
      help_id = g_object_get_qdata (G_OBJECT (action), GIMP_HELP_ID);

      accel_key = gtk_accel_group_find (accel_group,
                                        gimp_widget_accel_find_func,
                                        accel_closure);

      if (accel_key            &&
          accel_key->accel_key &&
          accel_key->accel_flags & GTK_ACCEL_VISIBLE)
        {
          gchar *escaped = g_markup_escape_text (tooltip, -1);
          gchar *accel   = gtk_accelerator_get_label (accel_key->accel_key,
                                                      accel_key->accel_mods);
          gchar *tmp     = g_strdup_printf ("%s  <b>%s</b>", escaped, accel);

          g_free (accel);
          g_free (escaped);

          gimp_help_set_help_data_with_markup (widget, tmp, help_id);
          g_free (tmp);
        }
      else
        {
          gimp_help_set_help_data (widget, tooltip, help_id);
        }

      g_free (tooltip);
    }
}

void
gimp_widget_set_accel_help (GtkWidget *widget,
                            GtkAction *action)
{
  GClosure *accel_closure = gtk_action_get_accel_closure (action);

  if (accel_closure)
    {
      GtkAccelGroup *accel_group;

      g_object_set_data (G_OBJECT (widget), "gimp-accel-closure",
                         accel_closure);
      g_object_set_data (G_OBJECT (widget), "gimp-accel-action",
                         action);

      accel_group = gtk_accel_group_from_accel_closure (accel_closure);

      g_signal_connect_object (accel_group, "accel-changed",
                               G_CALLBACK (gimp_widget_accel_changed),
                               widget, 0);

      gimp_widget_accel_changed (accel_group,
                                 0, 0,
                                 accel_closure,
                                 widget);
    }
  else
    {
      gchar *tooltip;
      gchar *help_id;

      g_object_get (action, "tooltip", &tooltip, NULL);
      help_id = g_object_get_qdata (G_OBJECT (action), GIMP_HELP_ID);

      gimp_help_set_help_data (widget, tooltip, help_id);

      g_free (tooltip);
    }
}

const gchar *
gimp_get_message_stock_id (GimpMessageSeverity severity)
{
  switch (severity)
    {
    case GIMP_MESSAGE_INFO:
      return GIMP_STOCK_INFO;

    case GIMP_MESSAGE_WARNING:
      return GIMP_STOCK_WARNING;

    case GIMP_MESSAGE_ERROR:
      return GIMP_STOCK_ERROR;
    }

  g_return_val_if_reached (GIMP_STOCK_WARNING);
}