gstdoc-scangobj

#!/usr/bin/env perl
# -*- cperl -*-
#
# gtk-doc - GTK DocBook documentation generator.
# Copyright (C) 1998  Damon Chaplin
#
# 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., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA.
#

#
# This gets information about object hierarchies and signals
# by compiling a small C program. CFLAGS and LDFLAGS must be
# set appropriately before running this script.
#

use Getopt::Long;

my $GTK_DOC_PREFIX=`pkg-config --variable prefix gtk-doc`;
if ($GTK_DOC_PREFIX) {
  chomp $GTK_DOC_PREFIX;
  #print "Adding $GTK_DOC_PREFIX/share/gtk-doc/data to \@INC\n";
  unshift @INC, "$GTK_DOC_PREFIX/share/gtk-doc/data";
} else {
  unshift @INC, '/usr/share/gtk-doc/data';
}
require "gtkdoc-common.pl";

# Options

# name of documentation module
my $MODULE;
my $OUTPUT_DIR;
my $INSPECT_DIR;
my $VERBOSE;
my $PRINT_VERSION;
my $PRINT_HELP;
my $TYPE_INIT_FUNC="g_type_init ()";

# --nogtkinit is deprecated, as it is the default now anyway.
%optctl = (module => \$MODULE,
           source => \$SOURCE,
	   types => \$TYPES_FILE,
	   nogtkinit => \$NO_GTK_INIT,
	   'type-init-func' => \$TYPE_INIT_FUNC,
	   'output-dir' => \$OUTPUT_DIR,
	   'inspect-dir' => \$INSPECT_DIR,
	   'verbose' => \$VERBOSE,
	   'version' => \$PRINT_VERSION,
	   'help' => \$PRINT_HELP);

GetOptions(\%optctl, "module=s", "source=s", "types:s", "output-dir:s", "inspect-dir:s", "nogtkinit", "type-init-func:s", "verbose", "version", "help");

if ($NO_GTK_INIT) {
  # Do nothing. This just avoids a warning.
  # the option is not used anymore
}

if ($PRINT_VERSION) {
    print "1.5\n";
    exit 0;
}

if (!$MODULE) {
    $PRINT_HELP = 1;
}

if ($PRINT_HELP) {
    print <<EOF;
gstdoc-scangobj version 1.5 - introspect gstreamer-plugins

--module=MODULE_NAME          Name of the doc module being parsed
--source=SOURCE_NAME          Name of the source module for plugins
--types=FILE                  The name of the file to store the types in
--type-init-func=FUNC         The init function to call instead of g_type_init()
--output-dir=DIRNAME          The directory where the results are stored
--inspect-dir=DIRNAME         The directory where the plugin inspect data is stored
--verbose                     Print extra output while processing
--version                     Print the version of this program
--help                        Print this help
EOF
    exit 0;
}

$OUTPUT_DIR = $OUTPUT_DIR ? $OUTPUT_DIR : ".";

$TYPES_FILE = $TYPES_FILE ? $TYPES_FILE : "$OUTPUT_DIR/$MODULE.types";

open (TYPES, $TYPES_FILE) || die "Cannot open $TYPES_FILE: $!\n";
open (OUTPUT, ">$MODULE-scan.c") || die "Cannot open $MODULE-scan.c: $!\n";

my $old_signals_filename = "$OUTPUT_DIR/$MODULE.signals";
my $new_signals_filename = "$OUTPUT_DIR/$MODULE.signals.new";
my $old_hierarchy_filename = "$OUTPUT_DIR/$MODULE.hierarchy";
my $new_hierarchy_filename = "$OUTPUT_DIR/$MODULE.hierarchy.new";
my $old_interfaces_filename = "$OUTPUT_DIR/$MODULE.interfaces";
my $new_interfaces_filename = "$OUTPUT_DIR/$MODULE.interfaces.new";
my $old_prerequisites_filename = "$OUTPUT_DIR/$MODULE.prerequisites";
my $new_prerequisites_filename = "$OUTPUT_DIR/$MODULE.prerequisites.new";
my $old_args_filename = "$OUTPUT_DIR/$MODULE.args";
my $new_args_filename = "$OUTPUT_DIR/$MODULE.args.new";

my $debug_log="g_message";
if (!defined($VERBOSE) or $VERBOSE eq "0") {
    $debug_log="//$debug_log";
}

# write a C program to scan the types

$includes = "";
@types = ();
@impl_types = ();

for (<TYPES>) {
    if (/^#include/) {
	$includes .= $_;
    } elsif (/^%/) {
	next;
    } elsif (/^\s*$/) {
	next;
    } elsif (/^type:(.*)$/) {
	$t = $1;
        chomp $t;
	push @impl_types, $t;
    } else {
	chomp;
	push @types, $_;
    }
}

$ntypes = @types + @impl_types + 1;

print OUTPUT <<EOT;

/* file generated by common/gstdoc-scangobj */

#include <string.h>
#include <stdlib.h>
#include <stdio.h>
#include <errno.h>

#include <gst/gst.h>
EOT

if ($includes) {
    print OUTPUT $includes;
} else {
    for (@types) {
        print OUTPUT "extern GType $_ (void);\n";
    }
}

print OUTPUT <<EOT;

#ifdef GTK_IS_WIDGET_CLASS
#include <gtk/gtkversion.h>
#endif

static GType *object_types = NULL;

static GString *xmlstr = NULL;

static const gchar*
xmlprint (gint indent, const gchar *tag, const gchar *data)
{
  const gchar indent_str[] = "                                               ";

  /* reset */
  g_string_truncate (xmlstr, 0);
  g_string_append_len (xmlstr, indent_str, MIN (indent, strlen (indent_str)));
  g_string_append_printf (xmlstr, "<%s>", tag);

  if (data) {
    gchar *s;

    s = g_markup_escape_text (data, -1);
    g_string_append (xmlstr, s);
    g_free (s);
  }

  g_string_append_printf (xmlstr, "</%s>\\n", tag);
  return xmlstr->str;
}

static gint
gst_feature_sort_compare (gconstpointer a, gconstpointer b)
{
  const gchar *name_a = gst_plugin_feature_get_name ((GstPluginFeature *) a);
  const gchar *name_b = gst_plugin_feature_get_name ((GstPluginFeature *) b);
  return strcmp (name_a, name_b);
}

static gint
static_pad_template_compare (gconstpointer a, gconstpointer b)
{
  GstStaticPadTemplate *spt_a = (GstStaticPadTemplate *) a;
  GstStaticPadTemplate *spt_b = (GstStaticPadTemplate *) b;

  /* we want SINK before SRC (enum is UNKNOWN, SRC, SINK) */
  if (spt_a->direction != spt_b->direction)
    return spt_b->direction - spt_a->direction;

  /* we want ALWAYS first, SOMETIMES second, REQUEST last
   * (enum is ALWAYS, SOMETIMES, REQUEST) */
  if (spt_a->presence != spt_b->presence)
    return spt_a->presence - spt_b->presence;

  return strcmp (spt_a->name_template, spt_b->name_template);
}

static GType *
get_object_types (void)
{
    gpointer g_object_class;
    GList *plugins = NULL;
    GList *factories = NULL;
    GList *l;
    GstElementFactory *factory = NULL;
    GType type;
    gint i = 0;
    gboolean reinspect;

    /* get a list of features from plugins in our source module */
    plugins = gst_registry_get_plugin_list (gst_registry_get ());

    xmlstr = g_string_new ("");

    reinspect = !g_file_test ("scanobj-build.stamp", G_FILE_TEST_EXISTS);

    while (plugins) {
      GList *features;
      GstPlugin *plugin;
      const gchar *source;
      FILE *inspect = NULL;
      gchar *inspect_name;

      plugin = (GstPlugin *) (plugins->data);
      plugins = g_list_next (plugins);
      source = gst_plugin_get_source (plugin);
      if (!source || strcmp (source, "$SOURCE") != 0) {
        continue;
      }

      /* skip static coreelements plugin with pipeline and bin element factory */
      if (gst_plugin_get_filename (plugin) == NULL)
        continue;

      $debug_log ("plugin: %s source: %s", gst_plugin_get_name (plugin), source);

      if (reinspect) {
        gchar *basename;

        inspect_name = g_strdup_printf ("$INSPECT_DIR" G_DIR_SEPARATOR_S "plugin-%s.xml",
            gst_plugin_get_name (plugin));
        inspect = fopen (inspect_name, "w");
        if (inspect == NULL) {
          g_error ("Could not open %s for writing: %s\\n", inspect_name,
              g_strerror (errno));
        }
        g_free (inspect_name);

		  basename = g_path_get_basename (gst_plugin_get_filename (plugin));

        /* output plugin data */
        fputs ("<plugin>\\n",inspect);
        fputs (xmlprint(2, "name", gst_plugin_get_name (plugin)),inspect);
        fputs (xmlprint(2, "description", gst_plugin_get_description (plugin)),inspect);
        fputs (xmlprint(2, "filename", gst_plugin_get_filename (plugin)),inspect);
        fputs (xmlprint(2, "basename", basename),inspect);
        fputs (xmlprint(2, "version", gst_plugin_get_version (plugin)),inspect);
        fputs (xmlprint(2, "license", gst_plugin_get_license (plugin)),inspect);
        fputs (xmlprint(2, "source", gst_plugin_get_source (plugin)),inspect);
        fputs (xmlprint(2, "package", gst_plugin_get_package (plugin)),inspect);
        fputs (xmlprint(2, "origin", gst_plugin_get_origin (plugin)),inspect);
        fputs ("  <elements>\\n", inspect);

		  g_free (basename);
      }

      features =
          gst_registry_get_feature_list_by_plugin (gst_registry_get (),
          gst_plugin_get_name (plugin));

      /* sort factories by feature->name */
      features = g_list_sort (features, gst_feature_sort_compare);

      while (features) {
        GstPluginFeature *feature;
        feature = GST_PLUGIN_FEATURE (features->data);
        feature = gst_plugin_feature_load (feature);
        if (!feature) {
          g_warning ("Could not load plugin feature %s",
                     gst_plugin_feature_get_name (feature));
        }

        if (GST_IS_ELEMENT_FACTORY (feature)) {
          const gchar *pad_dir[] = { "unknown","source","sink" };
          const gchar *pad_pres[] = { "always","sometimes","request" };
          GList *pads, *pad;

          $debug_log ("  feature: %s", gst_plugin_feature_get_name (feature));

          factory = GST_ELEMENT_FACTORY (feature);
          factories = g_list_prepend (factories, factory);

          if (reinspect) {
            /* output element data */
            fputs ("    <element>\\n", inspect);
            fputs (xmlprint(6, "name", gst_plugin_feature_get_name (feature)),inspect);
            fputs (xmlprint(6, "longname", gst_element_factory_get_metadata (factory, GST_ELEMENT_METADATA_LONGNAME)),inspect);
            fputs (xmlprint(6, "class", gst_element_factory_get_metadata (factory, GST_ELEMENT_METADATA_KLASS)),inspect);
            fputs (xmlprint(6, "description", gst_element_factory_get_metadata (factory, GST_ELEMENT_METADATA_DESCRIPTION)),inspect);
            fputs (xmlprint(6, "author", gst_element_factory_get_metadata (factory, GST_ELEMENT_METADATA_AUTHOR)),inspect);
            fputs ("      <pads>\\n", inspect);

            /* output pad-template data */
            pads = g_list_copy ((GList *) gst_element_factory_get_static_pad_templates (factory));
            pads = g_list_sort (pads, static_pad_template_compare);
            for (pad = pads; pad != NULL; pad = pad->next) {
              GstStaticPadTemplate *pt = pad->data;

              fputs ("        <caps>\\n", inspect);
              fputs (xmlprint(10, "name", pt->name_template),inspect);
              fputs (xmlprint(10, "direction", pad_dir[pt->direction]),inspect);
              fputs (xmlprint(10, "presence", pad_pres[pt->presence]),inspect);
              fputs (xmlprint(10, "details", pt->static_caps.string),inspect);
              fputs ("        </caps>\\n", inspect);
            }
            g_list_free (pads);
            fputs ("      </pads>\\n    </element>\\n", inspect);
          }
        }
        features = g_list_next (features);
      }

      if (reinspect) {
        fputs ("  </elements>\\n</plugin>", inspect);
        fclose (inspect);
      }
    }

    g_string_free (xmlstr, TRUE);

    $debug_log ("number of element factories: %d", g_list_length (factories));

    /* allocate the object_types array to hold them */
    object_types = g_new0 (GType, g_list_length (factories)+$ntypes+1);

    l = factories;
    i = 0;

    /* fill it */
    while (l) {
      factory = GST_ELEMENT_FACTORY (l->data);
      type = gst_element_factory_get_element_type (factory);
      if (type != 0) {
        $debug_log ("adding type for factory %s", gst_element_factory_get_metadata (factory, GST_ELEMENT_METADATA_LONGNAME));
        object_types[i++] = type;
      } else {
        g_message ("type info for factory %s not found",
            gst_element_factory_get_metadata (factory, GST_ELEMENT_METADATA_LONGNAME));
      }
      l = g_list_next (l);
    }

EOT

# get_type functions:
for (@types) {
print OUTPUT <<EOT;
    type = $_ ();
    if (type == 0) {
      g_message ("$_ () didn't return a valid type");
    }
    else {
      object_types[i++] = type;
    }
EOT
}

# Implicit types retrieved from GLib:
for (@impl_types) {
print OUTPUT <<EOT;
    type = g_type_from_name ("$_");
    if (type == 0) {
      g_message ("Implicit type $_ not found");
    }
    else {
      object_types[i++] = type;
    }
EOT
}

print OUTPUT <<EOT;

    object_types[i] = 0;

    /* reference the GObjectClass to initialize the param spec pool
     * potentially needed by interfaces. See http://bugs.gnome.org/571820 */
    g_object_class = g_type_class_ref (G_TYPE_OBJECT);

    /* Need to make sure all the types are loaded in and initialize
     * their signals and properties.
     */
    for (i=0; object_types[i]; i++)
      {
        if (G_TYPE_IS_CLASSED (object_types[i]))
          g_type_class_ref (object_types[i]);
        if (G_TYPE_IS_INTERFACE (object_types[i]))
          g_type_default_interface_ref (object_types[i]);
      }

    g_type_class_unref (g_object_class);

    return object_types;
}

/*
 * This uses GObject type functions to output signal prototypes and the object
 * hierarchy.
 */

/* The output files */
const gchar *signals_filename = "$new_signals_filename";
const gchar *hierarchy_filename = "$new_hierarchy_filename";
const gchar *interfaces_filename = "$new_interfaces_filename";
const gchar *prerequisites_filename = "$new_prerequisites_filename";
const gchar *args_filename = "$new_args_filename";


static void output_signals (void);
static void output_object_signals (FILE *fp,
				   GType object_type);
static void output_object_signal (FILE *fp,
				  const gchar *object_class_name,
				  guint signal_id);
static const gchar * get_type_name (GType type,
			            gboolean * is_pointer);
static void output_object_hierarchy (void);
static void output_hierarchy (FILE *fp,
			      GType type,
			      guint level);

static void output_object_interfaces (void);
static void output_interfaces (FILE *fp,
			       GType type);

static void output_interface_prerequisites (void);
static void output_prerequisites (FILE *fp,
			          GType type);

static void output_args (void);
static void output_object_args (FILE *fp, GType object_type);

int
main (G_GNUC_UNUSED int argc, G_GNUC_UNUSED char *argv[])
{
  $TYPE_INIT_FUNC;

  get_object_types ();

  output_signals ();
  output_object_hierarchy ();
  output_object_interfaces ();
  output_interface_prerequisites ();
  output_args ();

  return 0;
}


static void
output_signals (void)
{
  FILE *fp;
  gint i;

  fp = fopen (signals_filename, "w");
  if (fp == NULL)
    {
      g_warning ("Couldn't open output file: %s : %s", signals_filename, g_strerror(errno));
      return;
    }

  for (i = 0; object_types[i]; i++)
    output_object_signals (fp, object_types[i]);

  fclose (fp);
}

static gint
compare_signals (const void *a, const void *b)
{
  const guint *signal_a = a;
  const guint *signal_b = b;

  return strcmp (g_signal_name (*signal_a), g_signal_name (*signal_b));
}

/* This outputs all the signals of one object. */
static void
output_object_signals (FILE *fp, GType object_type)
{
  const gchar *object_class_name;
  guint *signals, n_signals;
  guint sig;

  if (G_TYPE_IS_INSTANTIATABLE (object_type) ||
      G_TYPE_IS_INTERFACE (object_type))
    {

      object_class_name = g_type_name (object_type);

      signals = g_signal_list_ids (object_type, &n_signals);
      qsort (signals, n_signals, sizeof (guint), compare_signals);

      for (sig = 0; sig < n_signals; sig++)
        {
           output_object_signal (fp, object_class_name, signals[sig]);
        }
      g_free (signals);
   }
}


/* This outputs one signal. */
static void
output_object_signal (FILE *fp,
		      const gchar *object_name,
		      guint signal_id)
{
  GSignalQuery query_info;
  const gchar *type_name, *ret_type, *object_arg, *arg_name;
  gchar *pos, *object_arg_lower;
  gboolean is_pointer;
  gchar buffer[1024];
  guint i, param;
  gint param_num, widget_num, event_num, callback_num;
  gint *arg_num;
  gchar signal_name[128];
  gchar flags[16];

  $debug_log ("Object: %s Signal: %u", object_name, signal_id);

  param_num = 1;
  widget_num = event_num = callback_num = 0;

  g_signal_query (signal_id, &query_info);

  /* Output the signal object type and the argument name. We assume the
     type is a pointer - I think that is OK. We remove "Gtk" or "Gnome" and
     convert to lower case for the argument name. */
  pos = buffer;
  sprintf (pos, "%s ", object_name);
  pos += strlen (pos);

  /* Try to come up with a sensible variable name for the first arg
   * It chops off 2 know prefixes :/ and makes the name lowercase
   * It should replace lowercase -> uppercase with '_'
   * GFileMonitor -> file_monitor
   * GIOExtensionPoint -> extension_point
   * GtkTreeView -> tree_view
   * if 2nd char is upper case too
   *   search for first lower case and go back one char
   * else
   *   search for next upper case
   */
  if (!strncmp (object_name, "Gtk", 3))
      object_arg = object_name + 3;
  else if (!strncmp (object_name, "Gnome", 5))
      object_arg = object_name + 5;
  else
      object_arg = object_name;

  object_arg_lower = g_ascii_strdown (object_arg, -1);
  sprintf (pos, "*%s\\n", object_arg_lower);
  pos += strlen (pos);
  if (!strncmp (object_arg_lower, "widget", 6))
    widget_num = 2;
  g_free(object_arg_lower);

  /* Convert signal name to use underscores rather than dashes '-'. */
  strncpy (signal_name, query_info.signal_name, 127);
  signal_name[127] = '\\0';
  for (i = 0; signal_name[i]; i++)
    {
      if (signal_name[i] == '-')
	signal_name[i] = '_';
    }

  /* Output the signal parameters. */
  for (param = 0; param < query_info.n_params; param++)
    {
      type_name = get_type_name (query_info.param_types[param] & ~G_SIGNAL_TYPE_STATIC_SCOPE, &is_pointer);

      /* Most arguments to the callback are called "arg1", "arg2", etc.
         GtkWidgets are called "widget", "widget2", ...
         GtkCallbacks are called "callback", "callback2", ... */
      if (!strcmp (type_name, "GtkWidget"))
        {
          arg_name = "widget";
          arg_num = &widget_num;
        }
      else if (!strcmp (type_name, "GtkCallback")
               || !strcmp (type_name, "GtkCCallback"))
        {
          arg_name = "callback";
          arg_num = &callback_num;
        }
      else
        {
          arg_name = "arg";
          arg_num = &param_num;
        }
      sprintf (pos, "%s ", type_name);
      pos += strlen (pos);

      if (!arg_num || *arg_num == 0)
        sprintf (pos, "%s%s\\n", is_pointer ? "*" : " ", arg_name);
      else
        sprintf (pos, "%s%s%i\\n", is_pointer ? "*" : " ", arg_name,
                 *arg_num);
      pos += strlen (pos);

      if (arg_num)
        {
          if (*arg_num == 0)
            *arg_num = 2;
          else
            *arg_num += 1;
        }
    }

  pos = flags;
  /* We use one-character flags for simplicity. */
  if (query_info.signal_flags & G_SIGNAL_RUN_FIRST)
    *pos++ = 'f';
  if (query_info.signal_flags & G_SIGNAL_RUN_LAST)
    *pos++ = 'l';
  if (query_info.signal_flags & G_SIGNAL_RUN_CLEANUP)
    *pos++ = 'c';
  if (query_info.signal_flags & G_SIGNAL_NO_RECURSE)
    *pos++ = 'r';
  if (query_info.signal_flags & G_SIGNAL_DETAILED)
    *pos++ = 'd';
  if (query_info.signal_flags & G_SIGNAL_ACTION)
    *pos++ = 'a';
  if (query_info.signal_flags & G_SIGNAL_NO_HOOKS)
    *pos++ = 'h';
  *pos = 0;

  /* Output the return type and function name. */
  ret_type = get_type_name (query_info.return_type & ~G_SIGNAL_TYPE_STATIC_SCOPE, &is_pointer);

  fprintf (fp,
	   "<SIGNAL>\\n<NAME>%s::%s</NAME>\\n<RETURNS>%s%s</RETURNS>\\n<FLAGS>%s</FLAGS>\\n%s</SIGNAL>\\n\\n",
	   object_name, query_info.signal_name, ret_type, is_pointer ? "*" : "", flags, buffer);
}


/* Returns the type name to use for a signal argument or return value, given
   the GtkType from the signal info. It also sets is_pointer to TRUE if the
   argument needs a '*' since it is a pointer. */
static const gchar *
get_type_name (GType type, gboolean * is_pointer)
{
  const gchar *type_name;

  *is_pointer = FALSE;
  type_name = g_type_name (type);

  switch (type) {
  case G_TYPE_NONE:
  case G_TYPE_CHAR:
  case G_TYPE_UCHAR:
  case G_TYPE_BOOLEAN:
  case G_TYPE_INT:
  case G_TYPE_UINT:
  case G_TYPE_LONG:
  case G_TYPE_ULONG:
  case G_TYPE_FLOAT:
  case G_TYPE_DOUBLE:
  case G_TYPE_POINTER:
    /* These all have normal C type names so they are OK. */
    return type_name;

  case G_TYPE_STRING:
    /* A GtkString is really a gchar*. */
    *is_pointer = TRUE;
    return "gchar";

  case G_TYPE_ENUM:
  case G_TYPE_FLAGS:
    /* We use a gint for both of these. Hopefully a subtype with a decent
       name will be registered and used instead, as GTK+ does itself. */
    return "gint";

  case G_TYPE_BOXED:
    /* The boxed type shouldn't be used itself, only subtypes. Though we
       return 'gpointer' just in case. */
    return "gpointer";

  case G_TYPE_PARAM:
    /* A GParam is really a GParamSpec*. */
    *is_pointer = TRUE;
    return "GParamSpec";

#if GLIB_CHECK_VERSION (2, 25, 9)
  case G_TYPE_VARIANT:
    *is_pointer = TRUE;
    return "GVariant";
#endif

default:
    break;
  }

  /* For all GObject subclasses we can use the class name with a "*",
     e.g. 'GtkWidget *'. */
  if (g_type_is_a (type, G_TYPE_OBJECT))
    *is_pointer = TRUE;

  /* Also catch non GObject root types */
  if (G_TYPE_IS_CLASSED (type))
    *is_pointer = TRUE;

  /* All boxed subtypes will be pointers as well. */
  /* Exception: GStrv */
  if (g_type_is_a (type, G_TYPE_BOXED) &&
      !g_type_is_a (type, G_TYPE_STRV))
    *is_pointer = TRUE;

  /* All pointer subtypes will be pointers as well. */
  if (g_type_is_a (type, G_TYPE_POINTER))
    *is_pointer = TRUE;

  /* But enums are not */
  if (g_type_is_a (type, G_TYPE_ENUM) ||
      g_type_is_a (type, G_TYPE_FLAGS))
    *is_pointer = FALSE;

  return type_name;
}


/* This outputs the hierarchy of all objects which have been initialized,
   i.e. by calling their XXX_get_type() initialization function. */
static void
output_object_hierarchy (void)
{
  FILE *fp;
  gint i,j;
  GType root, type;
  GType root_types[$ntypes] = { G_TYPE_INVALID, };

  fp = fopen (hierarchy_filename, "w");
  if (fp == NULL)
    {
      g_warning ("Couldn't open output file: %s : %s", hierarchy_filename, g_strerror(errno));
      return;
    }
  output_hierarchy (fp, G_TYPE_OBJECT, 0);
  output_hierarchy (fp, G_TYPE_INTERFACE, 0);

  for (i=0; object_types[i]; i++) {
    root = object_types[i];
    while ((type = g_type_parent (root))) {
      root = type;
    }
    if ((root != G_TYPE_OBJECT) && (root != G_TYPE_INTERFACE)) {
      for (j=0; root_types[j]; j++) {
        if (root == root_types[j]) {
          root = G_TYPE_INVALID; break;
        }
      }
      if(root) {
        root_types[j] = root;
        output_hierarchy (fp, root, 0);
      }
    }
  }

  fclose (fp);
}

static int
compare_types (const void *a, const void *b)
{
  const char *na = g_type_name (*((GType *)a));
  const char *nb = g_type_name (*((GType *)b));

  return g_strcmp0 (na, nb);
}


/* This is called recursively to output the hierarchy of a object. */
static void
output_hierarchy (FILE  *fp,
		  GType  type,
		  guint   level)
{
  guint i;
  GType *children;
  guint n_children;

  if (!type)
    return;

  for (i = 0; i < level; i++)
    fprintf (fp, "  ");
  fprintf (fp, "%s\\n", g_type_name (type));

  children = g_type_children (type, &n_children);
  qsort (children, n_children, sizeof (GType), compare_types);


  for (i=0; i < n_children; i++)
    output_hierarchy (fp, children[i], level + 1);

  g_free (children);
}

static void output_object_interfaces (void)
{
  guint i;
  FILE *fp;

  fp = fopen (interfaces_filename, "w");
  if (fp == NULL)
    {
      g_warning ("Couldn't open output file: %s : %s", interfaces_filename, g_strerror(errno));
      return;
    }
  output_interfaces (fp, G_TYPE_OBJECT);

  for (i = 0; object_types[i]; i++)
    {
      if (!g_type_parent (object_types[i]) &&
          (object_types[i] != G_TYPE_OBJECT) &&
          G_TYPE_IS_INSTANTIATABLE (object_types[i]))
        {
          output_interfaces (fp, object_types[i]);
        }
    }
  fclose (fp);
}

static void
output_interfaces (FILE  *fp,
		   GType  type)
{
  guint i;
  GType *children, *interfaces;
  guint n_children, n_interfaces;

  if (!type)
    return;

  interfaces = g_type_interfaces (type, &n_interfaces);

  if (n_interfaces > 0)
    {
      fprintf (fp, "%s", g_type_name (type));
      for (i=0; i < n_interfaces; i++)
          fprintf (fp, " %s", g_type_name (interfaces[i]));
      fprintf (fp, "\\n");
     }
  g_free (interfaces);

  children = g_type_children (type, &n_children);

  for (i=0; i < n_children; i++)
    output_interfaces (fp, children[i]);

  g_free (children);
}

static void output_interface_prerequisites (void)
{
  FILE *fp;

  fp = fopen (prerequisites_filename, "w");
  if (fp == NULL)
    {
      g_warning ("Couldn't open output file: %s : %s", prerequisites_filename, g_strerror(errno));
      return;
    }
  output_prerequisites (fp, G_TYPE_INTERFACE);
  fclose (fp);
}

static void
output_prerequisites (FILE  *fp,
		      GType  type)
{
#if GLIB_CHECK_VERSION(2,1,0)
  guint i;
  GType *children, *prerequisites;
  guint n_children, n_prerequisites;

  if (!type)
    return;

  prerequisites = g_type_interface_prerequisites (type, &n_prerequisites);

  if (n_prerequisites > 0)
    {
      fprintf (fp, "%s", g_type_name (type));
      for (i=0; i < n_prerequisites; i++)
          fprintf (fp, " %s", g_type_name (prerequisites[i]));
      fprintf (fp, "\\n");
     }
  g_free (prerequisites);

  children = g_type_children (type, &n_children);

  for (i=0; i < n_children; i++)
    output_prerequisites (fp, children[i]);

  g_free (children);
#endif
}

static void
output_args (void)
{
  FILE *fp;
  gint i;

  fp = fopen (args_filename, "w");
  if (fp == NULL)
    {
      g_warning ("Couldn't open output file: %s : %s", args_filename, g_strerror(errno));
      return;
    }

  for (i = 0; object_types[i]; i++) {
    output_object_args (fp, object_types[i]);
  }

  fclose (fp);
}

static gint
compare_param_specs (const void *a, const void *b)
{
  GParamSpec *spec_a = *(GParamSpec **)a;
  GParamSpec *spec_b = *(GParamSpec **)b;

  return strcmp (g_param_spec_get_name (spec_a), g_param_spec_get_name (spec_b));
}

/* Its common to have unsigned properties restricted
 * to the signed range. Therefore we make this look
 * a bit nicer by spelling out the max constants.
 */

/* Don't use "==" with floats, it might trigger a gcc warning.  */
#define GTKDOC_COMPARE_FLOAT(x, y) (x <= y && x >= y)

static gchar*
describe_double_constant (gdouble value)
{
  gchar *desc;

  if (GTKDOC_COMPARE_FLOAT (value, G_MAXDOUBLE))
    desc = g_strdup ("G_MAXDOUBLE");
  else if (GTKDOC_COMPARE_FLOAT (value, G_MINDOUBLE))
    desc = g_strdup ("G_MINDOUBLE");
  else if (GTKDOC_COMPARE_FLOAT (value, -G_MAXDOUBLE))
    desc = g_strdup ("-G_MAXDOUBLE");
  else if (GTKDOC_COMPARE_FLOAT (value, G_MAXFLOAT))
    desc = g_strdup ("G_MAXFLOAT");
  else if (GTKDOC_COMPARE_FLOAT (value, G_MINFLOAT))
    desc = g_strdup ("G_MINFLOAT");
  else if (GTKDOC_COMPARE_FLOAT (value, -G_MAXFLOAT))
    desc = g_strdup ("-G_MAXFLOAT");
  else{
    /* make sure floats are output with a decimal dot irrespective of
    * current locale. Use formatd since we want human-readable numbers
    * and do not need the exact same bit representation when deserialising */
    desc = g_malloc0 (G_ASCII_DTOSTR_BUF_SIZE);
    g_ascii_formatd (desc, G_ASCII_DTOSTR_BUF_SIZE, "%g", value);
  }

  return desc;
}

static gchar*