viewer-render.c

Pango is a library for layout and rendering of text, with an emphasis on internationalization. Pang

  g_object_unref (layout);
}

static gboolean
parse_enum (GType       type,
	    int        *value,
	    const char *name,
	    const char *arg,
	    gpointer    data,
	    GError **error)
{
  char *possible_values = NULL;
  gboolean ret;

  ret = pango_parse_enum (type,
			  arg,
			  value,
			  FALSE,
			  &possible_values);

  if (!ret && error)
    {
      g_set_error(error,
		  G_OPTION_ERROR,
		  G_OPTION_ERROR_BAD_VALUE,
		  "Argument for %s must be one of %s",
		  name,
		  possible_values);
      ret = FALSE;
    }

  g_free (possible_values);

  return ret;
}

static gboolean
parse_align (const char *name,
	     const char *arg,
	     gpointer    data,
	     GError **error)
{
  return parse_enum (PANGO_TYPE_ALIGNMENT, &opt_align,
		     name, arg, data, error);
}

static gboolean
parse_ellipsis (const char *name,
		const char *arg,
		gpointer    data,
		GError **error)
{
  return parse_enum (PANGO_TYPE_ELLIPSIZE_MODE, &opt_ellipsize,
		     name, arg, data, error);
}

static gboolean
parse_gravity (const char *name,
	       const char *arg,
	       gpointer    data,
	       GError **error)
{
  return parse_enum (PANGO_TYPE_GRAVITY, &opt_gravity,
		     name, arg, data, error);
}

static gboolean
parse_gravity_hint (const char *name,
		    const char *arg,
		    gpointer    data,
		    GError **error)
{
  return parse_enum (PANGO_TYPE_GRAVITY_HINT, &opt_gravity_hint,
		     name, arg, data, error);
}

static gboolean
parse_hinting (const char *name,
	       const char *arg,
	       gpointer    data,
	       GError    **error)
{
  gboolean ret = TRUE;

  if (strcmp (arg, "none") == 0)
    opt_hinting = HINT_NONE;
  else if (strcmp (arg, "auto") == 0)
    opt_hinting = HINT_AUTO;
  else if (strcmp (arg, "full") == 0)
    opt_hinting = HINT_FULL;
  else
    {
      g_set_error(error,
		  G_OPTION_ERROR,
		  G_OPTION_ERROR_BAD_VALUE,
		  "Argument for --hinting must be one of none/auto/full");
      ret = FALSE;
    }

  return ret;
}

static gboolean
parse_wrap (const char *name,
	    const char *arg,
	    gpointer    data,
	    GError    **error)
{
  gboolean ret;
  if ((ret = parse_enum (PANGO_TYPE_WRAP_MODE, &opt_wrap,
			 name, arg, data, error)))
    {
      opt_wrap_set = TRUE;
    }
  return ret;
}

static gchar *
backends_to_string (void)
{
  GString *backends = g_string_new (NULL);
  const PangoViewer **viewer;

  for (viewer = viewers; *viewer; viewer++)
    if ((*viewer)->id)
      {
	g_string_append (backends, (*viewer)->id);
	g_string_append_c (backends, '/');
      }
  g_string_truncate (backends, MAX (0, (gint)backends->len - 1));

  return g_string_free(backends,FALSE);
}

static int
backends_get_count (void)
{
  const PangoViewer **viewer;
  int i = 0;

  for (viewer = viewers; *viewer; viewer++)
    if ((*viewer)->id)
      i++;

  return i;
}


static gchar *
backend_description (void)
{
 GString *description  = g_string_new("Pango backend to use for rendering ");
 int backends_count = backends_get_count ();

 if (backends_count > 1)
   g_string_append_printf(description,"(default: %s)", (*viewers)->id);
 else if (backends_count == 1)
   g_string_append_printf(description,"(only available: %s)", (*viewers)->id);
 else
   g_string_append_printf(description,"(no backends found!)");

 return g_string_free(description,FALSE);

}

static gboolean
parse_backend (const char *name,
	       const char *arg,
	       gpointer    data,
	       GError    **error)
{
  gboolean ret = TRUE;
  const PangoViewer **viewer;

  for (viewer = viewers; *viewer; viewer++)
    if (!g_ascii_strcasecmp ((*viewer)->id, arg))
      break;

  if (*viewer)
    opt_viewer = *viewer;
  else
    {
      gchar *backends = backends_to_string ();

      g_set_error(error,
		  G_OPTION_ERROR,
		  G_OPTION_ERROR_BAD_VALUE,
		  "Available --backend options are: %s",
		  backends);
      g_free(backends);
      ret = FALSE;
    }

  return ret;
}


static gboolean
show_version(const char *name,
	     const char *arg,
	     gpointer    data,
	     GError    **error)
{
  g_printf("%s (%s) %s\n", prog_name, PACKAGE_NAME, PACKAGE_VERSION);
  g_printf("module interface version: %s\n", MODULE_VERSION);

  if (PANGO_VERSION != pango_version())
    g_printf("\nLinked Pango library has a different version: %s\n", pango_version_string ());

  exit(0);
}

void
parse_options (int argc, char *argv[])
{
  gchar *backend_options = backends_to_string ();
  GOptionFlags backend_flag = backends_get_count () > 1 ? 0 : G_OPTION_FLAG_HIDDEN;
  gchar *backend_desc = backend_description ();
  GOptionEntry entries[] =
  {
    {"no-auto-dir",	0, G_OPTION_FLAG_REVERSE, G_OPTION_ARG_NONE,	&opt_auto_dir,
     "No layout direction according to contents",			NULL},
    {"backend",		0, backend_flag, G_OPTION_ARG_CALLBACK,		&parse_backend,
     backend_desc,					     backend_options},
    {"no-display",	'q', G_OPTION_FLAG_REVERSE, G_OPTION_ARG_NONE,	&opt_display,
     "Do not display (just write to file or whatever)",			NULL},
    {"dpi",		0, 0, G_OPTION_ARG_INT,				&opt_dpi,
     "Set the resolution",					    "number"},
    {"align",		0, 0, G_OPTION_ARG_CALLBACK,			&parse_align,
     "Text alignment",				         "left/center/right"},
    {"ellipsize",	0, 0, G_OPTION_ARG_CALLBACK,			&parse_ellipsis,
     "Ellipsization mode",				  "start/middle/end"},
    {"font",		0, 0, G_OPTION_ARG_STRING,			&opt_font,
     "Set the font description",			       "description"},
    {"gravity",		0, 0, G_OPTION_ARG_CALLBACK,			&parse_gravity,
     "Base gravity: glyph rotation",		"south/east/north/west/auto"},
    {"gravity-hint",	0, 0, G_OPTION_ARG_CALLBACK,			&parse_gravity_hint,
     "Gravity hint",				       "natural/strong/line"},
    {"header",		0, 0, G_OPTION_ARG_NONE,			&opt_header,
     "Display the options in the output",				NULL},
    {"height",		0, 0, G_OPTION_ARG_INT,				&opt_height,
     "Height in points (positive) or number of lines (negative) for ellipsizing", "+points/-numlines"},
    {"hinting",		0, 0, G_OPTION_ARG_CALLBACK,			&parse_hinting,
     "Hinting style",					    "none/auto/full"},
    {"indent",		0, 0, G_OPTION_ARG_INT,				&opt_indent,
     "Width in points to indent paragraphs",			    "points"},
    {"justify",		0, 0, G_OPTION_ARG_NONE,			&opt_justify,
     "Align paragraph lines to be justified",			    	NULL},
    {"language",	0, 0, G_OPTION_ARG_STRING,			&opt_language,
     "Language to use for font selection",			    "en_US/etc"},
    {"margin",		0, 0, G_OPTION_ARG_INT,				&opt_margin,
     "Set the margin on the output in pixels",			    "pixels"},
    {"markup",		0, 0, G_OPTION_ARG_NONE,			&opt_markup,
     "Interpret text as Pango markup",					NULL},
    {"output",		'o', 0, G_OPTION_ARG_STRING,			&opt_output,
     "Save rendered image to output file",			      "file"},
    {"pangorc",		0, 0, G_OPTION_ARG_STRING,			&opt_pangorc,
     "pangorc file to use (default is ./pangorc)",		      "file"},
    {"rtl",		0, 0, G_OPTION_ARG_NONE,			&opt_rtl,
     "Set base direction to right-to-left",				NULL},
    {"rotate",		0, 0, G_OPTION_ARG_DOUBLE,			&opt_rotate,
     "Angle at which to rotate results",			   "degrees"},
    {"runs",		'n', 0, G_OPTION_ARG_INT,			&opt_runs,
     "Run Pango layout engine this many times",			   "integer"},
    {"single-par",	0, 0, G_OPTION_ARG_NONE,			&opt_single_par,
     "Enable single-paragraph mode",					NULL},
    {"text",		't', 0, G_OPTION_ARG_STRING,			&opt_text,
     "Text to display (instead of a file)",			    "string"},
    {"version",		0, G_OPTION_FLAG_NO_ARG, G_OPTION_ARG_CALLBACK, &show_version,
     "Show version numbers",						NULL},
    {"waterfall",	0, 0, G_OPTION_ARG_NONE,			&opt_waterfall,
     "Create a waterfall display",					NULL},
    {"width",		'w', 0, G_OPTION_ARG_INT,			&opt_width,
     "Width in points to which to wrap lines or ellipsize",	    "points"},
    {"wrap",		0, 0, G_OPTION_ARG_CALLBACK,			&parse_wrap,
     "Text wrapping mode (needs a width to be set)",   "word/char/word-char"},
    {NULL}
  };
  GError *error = NULL;
  GError *parse_error = NULL;
  GOptionContext *context;
  size_t len;

  prog_name = g_path_get_basename (argv[0]);
  context = g_option_context_new ("- FILE");
  g_option_context_add_main_entries (context, entries, NULL);
  if (!g_option_context_parse (context, &argc, &argv, &parse_error))
  {
    if (parse_error != NULL)
      fail("%s", parse_error->message);
    else
      fail("Option parse error");
    exit(1);
  }
  g_option_context_free(context);
  g_free(backend_options);
  g_free(backend_desc);

  if ((opt_text && argc != 1) || (!opt_text && argc != 2))
    {
      if (opt_text && argc != 1)
	fail ("When specifying --text, no file should be given");

      g_printerr ("Usage: %s [OPTION...] FILE\n", prog_name);
      exit (1);
    }

  /* set up the backend */
  if (!opt_viewer)
    {
      opt_viewer = *viewers;
      if (!opt_viewer)
	fail ("No viewer backend found");
    }

  /* Get the text
   */
  if (opt_text)
    {
      text = g_strdup (opt_text);
      len = strlen (text);
    }
  else
    {
      if (!g_file_get_contents (argv[1], &text, &len, &error))
	fail ("%s\n", error->message);
    }

  /* Strip one trailing newline
   */
  if (len > 0 && text[len - 1] == '\n')
    len--;
  if (len > 0 && text[len - 1] == '\r')
    len--;
  text[len] = '\0';

  /* Make sure we have valid markup
   */
  if (opt_markup &&
      !pango_parse_markup (text, -1, 0, NULL, NULL, NULL, &error))
    fail ("Cannot parse input as markup: %s", error->message);

  /* Setup PANGO_RC_FILE
   */
  if (!opt_pangorc)
    if (g_file_test ("./pangorc", G_FILE_TEST_IS_REGULAR))
      opt_pangorc = "./pangorc";
  if (opt_pangorc)
    g_setenv ("PANGO_RC_FILE", opt_pangorc, TRUE);
}


void
finalize (void)
{
  g_free (text);
}