gnome-control-center/gnome-settings-daemon/gnome-settings-xsettings.c

#include <config.h>
#include <string.h>
#include <stdio.h>
#include <glib.h>
#include <libgnome/gnome-i18n.h>

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

#include "gnome-settings-daemon.h"
#include "gnome-settings-xsettings.h"
#include "xsettings-manager.h"

extern XSettingsManager **managers;

#ifdef HAVE_XFT2
#define FONT_RENDER_DIR "/desktop/gnome/font_rendering"
#define FONT_ANTIALIASING_KEY FONT_RENDER_DIR "/antialiasing"
#define FONT_HINTING_KEY      FONT_RENDER_DIR "/hinting"
#define FONT_RGBA_ORDER_KEY   FONT_RENDER_DIR "/rgba_order"
#define FONT_DPI_KEY          FONT_RENDER_DIR "/dpi"
#endif /* HAVE_XFT2 */

typedef struct _TranslationEntry TranslationEntry;
typedef void (* TranslationFunc) (TranslationEntry *trans,
                                  GConfValue       *value);
struct _TranslationEntry
{
  const char *gconf_key;
  const char *xsetting_name;
  
  GConfValueType gconf_type;
  TranslationFunc translate;
};

#ifdef HAVE_XFT2 
static void gnome_settings_update_xft (GConfClient *client);
static void xft_callback              (GConfEntry  *entry);
#endif /* HAVE_XFT2 */

static void
translate_bool_int (TranslationEntry *trans,
		    GConfValue       *value)
{
  int i;

  g_assert (value->type == trans->gconf_type);
  
  for (i = 0; managers [i]; i++)  
    xsettings_manager_set_int (managers [i], trans->xsetting_name,
                               gconf_value_get_bool (value));
}

static void
translate_int_int (TranslationEntry *trans,
                   GConfValue       *value)
{
  int i;

  g_assert (value->type == trans->gconf_type);

  for (i = 0; managers [i]; i++)  
    xsettings_manager_set_int (managers [i], trans->xsetting_name,
                               gconf_value_get_int (value));
}

static void
translate_string_string (TranslationEntry *trans,
                         GConfValue       *value)
{
  int i;

  g_assert (value->type == trans->gconf_type);

  for (i = 0; managers [i]; i++)  
    xsettings_manager_set_string (managers [i],
                                  trans->xsetting_name,
                                  gconf_value_get_string (value));
}

static TranslationEntry translations [] = {
  { "/desktop/gnome/peripherals/mouse/double_click",	"Net/DoubleClickTime",
      GCONF_VALUE_INT,		translate_int_int },
  { "/desktop/gnome/peripherals/mouse/drag_threshold",  "Net/DndDragThreshold",
      GCONF_VALUE_INT,          translate_int_int },
  { "/desktop/gnome/gtk-color-palette",			"Gtk/ColorPalette",
      GCONF_VALUE_STRING,	translate_string_string },
  { "/desktop/gnome/interface/font_name",		"Gtk/FontName",
      GCONF_VALUE_STRING,	translate_string_string },
  { "/desktop/gnome/interface/gtk_key_theme",		"Gtk/KeyThemeName",
      GCONF_VALUE_STRING,	translate_string_string },
  { "/desktop/gnome/interface/toolbar_style",			"Gtk/ToolbarStyle",
      GCONF_VALUE_STRING,	translate_string_string },
  { "/desktop/gnome/interface/toolbar_icon_size",		"Gtk/ToolbarIconSize",
      GCONF_VALUE_STRING,	translate_string_string },
  { "/desktop/gnome/interface/can_change_accels",		"Gtk/CanChangeAccels",
      GCONF_VALUE_BOOL,		translate_bool_int },
  { "/desktop/gnome/interface/cursor_blink",		"Net/CursorBlink",
      GCONF_VALUE_BOOL,		translate_bool_int },
  { "/desktop/gnome/interface/cursor_blink_time",	"Net/CursorBlinkTime",
      GCONF_VALUE_INT,		translate_int_int },
  { "/desktop/gnome/interface/gtk_theme",		"Net/ThemeName",
      GCONF_VALUE_STRING,	translate_string_string },
  { "/desktop/gnome/interface/gtk-im-preedit-style",	"Gtk/IMPreeditStyle",
      GCONF_VALUE_STRING,	translate_string_string },
  { "/desktop/gnome/interface/gtk-im-status-style",	"Gtk/IMStatusStyle",
      GCONF_VALUE_STRING,	translate_string_string }
};

static TranslationEntry*
find_translation_entry (const char *gconf_key)
{
  int i;

  i = 0;
  while (i < G_N_ELEMENTS (translations))
    {
      if (strcmp (translations[i].gconf_key, gconf_key) == 0)
        return &translations[i];

      ++i;
    }

  return NULL;
}

static const gchar* 
type_to_string (GConfValueType type)
{
  switch (type)
    {
    case GCONF_VALUE_INT:
      return "int";
      break;
    case GCONF_VALUE_STRING:
      return "string";
      break;
    case GCONF_VALUE_FLOAT:
      return "float";
      break;
    case GCONF_VALUE_BOOL:
      return "bool";
      break;
    case GCONF_VALUE_SCHEMA:
      return "schema";
      break;
    case GCONF_VALUE_LIST:
      return "list";
      break;
    case GCONF_VALUE_PAIR:
      return "pair";
      break;
    case GCONF_VALUE_INVALID:
      return "*invalid*";
      break;
    default:
      g_assert_not_reached();
      return NULL; /* for warnings */
      break;
    }
}

static void
process_value (TranslationEntry *trans,
               GConfValue       *val)
{  
  if (val == NULL)
    {
      int i;

      for (i = 0; managers [i]; i++)  
        xsettings_manager_delete_setting (managers [i], trans->xsetting_name);
    }
  else
    {
      if (val->type == trans->gconf_type)
        {
          (* trans->translate) (trans, val);
        }
      else
        {
          g_warning (_("GConf key %s set to type %s but its expected type was %s\n"),
                     trans->gconf_key,
                     type_to_string (val->type),
                     type_to_string (trans->gconf_type));
        }
    }
}

static void
xsettings_callback (GConfEntry *entry)
{
  TranslationEntry *trans;
  int i;

  trans = find_translation_entry (entry->key);
  if (trans == NULL)
    return;

  process_value (trans, entry->value);
  
  for (i = 0; managers [i]; i++)  
    xsettings_manager_notify (managers [i]);
}

void
gnome_settings_xsettings_init (GConfClient *client)
{
  gnome_settings_daemon_register_callback ("/desktop/gnome/peripherals/mouse", xsettings_callback);
  gnome_settings_daemon_register_callback ("/desktop/gtk", xsettings_callback);
  gnome_settings_daemon_register_callback ("/desktop/gnome/interface", xsettings_callback);

#ifdef HAVE_XFT2  
  gnome_settings_daemon_register_callback (FONT_RENDER_DIR, xft_callback);
#endif /* HAVE_XFT2 */  
}

#ifdef HAVE_XFT2
static void
xft_callback (GConfEntry *entry)
{
  GConfClient *client;
  int i;

  client = gconf_client_get_default ();

  gnome_settings_update_xft (client);

  for (i = 0; managers [i]; i++)  
    xsettings_manager_notify (managers [i]);
}

typedef struct
{
  gboolean antialias;
  gboolean hinting;
  int dpi;
  const char *rgba;
  const char *hintstyle;
} GnomeXftSettings;

static const char *rgba_types[] = { "rgb", "bgr", "vbgr", "vrgb" };

/* Read GConf settings and determine the appropriate Xft settings based on them
 * This probably could be done a bit more cleanly with gconf_string_to_enum
 */
static void
gnome_xft_settings_get (GConfClient      *client,
			GnomeXftSettings *settings)
{
  char *antialiasing = gconf_client_get_string (client, FONT_ANTIALIASING_KEY, NULL);
  char *hinting = gconf_client_get_string (client, FONT_HINTING_KEY, NULL);
  char *rgba_order = gconf_client_get_string (client, FONT_RGBA_ORDER_KEY, NULL);
  double dpi = gconf_client_get_float (client, FONT_DPI_KEY, NULL);

  settings->antialias = TRUE;
  settings->hinting = TRUE;
  settings->hintstyle = "hintfull";
  settings->dpi = 96;
  settings->rgba = "rgb";

  if ((int)(1024 * dpi + 0.5) > 0)
    settings->dpi = (int)(1024 * dpi + 0.5);

  if (rgba_order)
    {
      int i;
      gboolean found = FALSE;

      for (i = 0; i < G_N_ELEMENTS (rgba_types) && !found; i++)
	if (strcmp (rgba_order, rgba_types[i]) == 0)
	  {
	    settings->rgba = rgba_types[i];
	    found = TRUE;
	  }

      if (!found)
	g_warning ("Invalid value for " FONT_RGBA_ORDER_KEY ": '%s'",
		   rgba_order);
    }
  
  if (hinting)
    {
      if (strcmp (hinting, "none") == 0)
	{
	  settings->hinting = 0;
	  settings->hintstyle = "hintnone";
	}
      else if (strcmp (hinting, "slight") == 0)
	{
	  settings->hinting = 1;
	  settings->hintstyle = "hintslight";
	}
      else if (strcmp (hinting, "medium") == 0)
	{
	  settings->hinting = 1;
	  settings->hintstyle = "hintmedium";
	}
      else if (strcmp (hinting, "full") == 0)
	{
	  settings->hinting = 1;
	  settings->hintstyle = "hintfull";
	}
      else
	g_warning ("Invalid value for " FONT_HINTING_KEY ": '%s'",
		   hinting);
    }
  
  if (antialiasing)
    {
      gboolean use_rgba = FALSE;
      
      if (strcmp (antialiasing, "none") == 0)
	settings->antialias = 0;
      else if (strcmp (antialiasing, "grayscale") == 0)
	settings->antialias = 1;
      else if (strcmp (antialiasing, "rgba") == 0)
	{
	  settings->antialias = 1;
	  use_rgba = TRUE;
	}
      else
	g_warning ("Invalid value for " FONT_ANTIALIASING_KEY " : '%s'",
		   antialiasing);

      if (!use_rgba)
	settings->rgba = "none";
    }

  g_free (rgba_order);
  g_free (hinting);
  g_free (antialiasing);
}

static void
gnome_xft_settings_set_xsettings (GnomeXftSettings *settings)
{
  int i;
  for (i = 0; managers [i]; i++)  
    {
      xsettings_manager_set_int (managers [i], "Xft/Antialias", settings->antialias);
      xsettings_manager_set_int (managers [i], "Xft/Hinting", settings->hinting);
      xsettings_manager_set_string (managers [i], "Xft/HintStyle", settings->hintstyle);
      xsettings_manager_set_int (managers [i], "Xft/DPI", settings->dpi);
      xsettings_manager_set_string (managers [i], "Xft/RGBA", settings->rgba);
    }
}

/*
 * Helper function for spawn_with_input() - write an entire
 * string to a fd.
 */
static gboolean
write_all (int         fd,
	   const char *buf,
	   gsize       to_write)
{
  while (to_write > 0)
    {
      gssize count = write (fd, buf, to_write);
      if (count < 0)
	{
	  if (errno != EINTR)
	    return FALSE;
	}
      else
	{
	  to_write -= count;
	  buf += count;
	}
    }

  return TRUE;
}

/*
 * Helper function for spawn_with_input() - wait for a child
 * to exit.
 */
gboolean
wait_for_child (int  pid,
		int *status)
{
  gint ret;

 again:
  ret = waitpid (pid, status, 0);

  if (ret < 0)
    {
      if (errno == EINTR)
        goto again;
      else
        {
	  g_warning ("Unexpected error in waitpid() (%s)",
		     g_strerror (errno));
	  return FALSE;
        }
    }

  return TRUE;
}

/**
 * spawn_with_input:
 * @argv: command line to run
 * @input: string to write to the child process. 
 * 
 * Spawns a child process specified by @argv, writes the text in
 * @input to it, then waits for the child to exit. Any failures
 * are output through g_warning(); if you wanted to use this in
 * cases where errors need to be presented to the user, some
 * modification would be needed.
 **/
static void
spawn_with_input (char      **argv,
		  const char *input)
{
  int exit_status;
  int child_pid;
  int inpipe;
  GError *err = NULL;
  
  if (!g_spawn_async_with_pipes (NULL /* working directory */, argv, NULL /* envp */,
				 G_SPAWN_SEARCH_PATH | G_SPAWN_DO_NOT_REAP_CHILD,
				 NULL, NULL, /* child setup and data */
				 &child_pid,
				 &inpipe, NULL, NULL, /* stdin, stdout, stderr */
				 &err))
    {
      gchar *command = g_strjoinv (" ", argv);
      g_warning ("Could not execute %s: %s", command, err->message);
      g_error_free (err);
      g_free (command);

      return;
    }

  if (input)
    {
      if (!write_all (inpipe, input, strlen (input)))
	{
	  gchar *command = g_strjoinv (" ", argv);
	  g_warning ("Could not write input to %s", command);
	  g_free (command);
	}

      close (inpipe);
    }
      
  wait_for_child (child_pid, &exit_status);

  if (!WIFEXITED (exit_status) || WEXITSTATUS (exit_status))
    {
      gchar *command = g_strjoinv (" ", argv);
      g_warning ("Command %s failed", command);
      g_free (command);
    }
}

static void
gnome_xft_settings_set_xresources (GnomeXftSettings *settings)
{
  char *add[] = { "xrdb", "-merge", NULL };
  GString *add_string = g_string_new (NULL);

  g_string_append_printf (add_string,
			  "Xft.dpi: %f\n", settings->dpi / 1024.);
  g_string_append_printf (add_string,
			  "Xft.antialias: %d\n", settings->antialias);
  g_string_append_printf (add_string,
			  "Xft.hinting: %d\n", settings->hinting);
  g_string_append_printf (add_string,
			  "Xft.hintstyle: %s\n", settings->hintstyle);
  g_string_append_printf (add_string,
			  "Xft.rgba: %s\n", settings->rgba);

  spawn_with_input (add, add_string->str);

  g_string_free (add_string, TRUE);
}

/* We mirror the Xft properties both through XSETTINGS and through
 * X resources
 */
static void
gnome_settings_update_xft (GConfClient *client)
{
  GnomeXftSettings settings;

  gnome_xft_settings_get (client, &settings);
  gnome_xft_settings_set_xsettings (&settings);
  gnome_xft_settings_set_xresources (&settings);
}
#endif /* HAVE_XFT2 */

void
gnome_settings_xsettings_load (GConfClient *client)
{
  int i;

  i = 0;
  while (i < G_N_ELEMENTS (translations))
    {
      GConfValue *val;
      GError *err;

      err = NULL;
      val = gconf_client_get (client,
                              translations[i].gconf_key,
                              &err);

      if (err != NULL)
        {
	  fprintf (stderr, "Error getting value for %s: %s\n",
                   translations[i].gconf_key, err->message);
          g_error_free (err);
        }
      else
        {
          process_value (&translations[i], val);
        }
      
      ++i;
    }

#ifdef HAVE_XFT2  
  gnome_settings_update_xft (client);
#endif /* HAVE_XFT */

  for (i = 0; managers [i]; i++)  
    xsettings_manager_notify (managers [i]);
}