Borrow argument parsing code from GDK.

Mon Sep 15 15:48:25 2003  Owen Taylor  <otaylor@redhat.com>

        * examples/Makefile.am examples/argcontext.c examples/argcontext.h:
        Borrow argument parsing code from GDK.

        * examples/pangoft2topgm.c: Use argcontext.[ch]. Add options
        --header to display options in a header in the image, --text
        to pass the text on the command line, --width to set a
        wrap width. Add autoconversion to non-PGM output formats
        via 'convert' for  --output="foo.png" etc.

5 files changed, 700 insertions, 225 deletions

diff --git a/examples/Makefile.am b/examples/Makefile.am
index 9b451564..f13b957d 100644
--- a/examples/Makefile.am
+++ b/examples/Makefile.am
@@ -21,7 +21,10 @@ if HAVE_FREETYPE
 ft2_programs = pangoft2topgm
 endif
 
-pangoft2topgm_SOURCES = pangoft2topgm.c
+pangoft2topgm_SOURCES =				\
+	pangoft2topgm.c				\
+	argcontext.c				\
+	argcontext.h
 pangoft2topgm_LDADD =					\
 	../pango/libpango-$(PANGO_API_VERSION).la	\
 	../pango/libpangoft2-$(PANGO_API_VERSION).la	\
diff --git a/examples/argcontext.c b/examples/argcontext.c
new file mode 100644
index 00000000..7160266c
--- /dev/null
+++ b/examples/argcontext.c
@@ -0,0 +1,248 @@
+/* argcontext.c - Simple command line argument parsing
+ * Copyright 1999, 2003 Red Hat Software
+ *
+ * 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.
+ */
+
+#include <string.h>
+#include <stdlib.h>
+#include <errno.h>
+
+#include "argcontext.h"
+
+struct _ArgContext
+{
+  GPtrArray *tables;
+  gpointer cb_data;
+};
+
+GQuark
+arg_context_error_quark (void)
+{
+  static GQuark q = 0;
+  if (q == 0)
+    q = g_quark_from_static_string ("arg-context-error-quark");
+
+  return q;
+}
+
+ArgContext *
+arg_context_new (gpointer cb_data)
+{
+  ArgContext *result = g_new (ArgContext, 1);
+  result->tables = g_ptr_array_new ();
+  result->cb_data = cb_data;
+
+  return result;
+}
+
+void
+arg_context_free (ArgContext *context)
+{
+  g_ptr_array_free (context->tables, TRUE);
+  g_free (context);
+}
+
+void
+arg_context_add_table (ArgContext    *context,
+		       const ArgDesc *table)
+{
+  g_ptr_array_add (context->tables, (ArgDesc *)table);
+}
+
+static gboolean
+parse_int (const char *arg_name,
+	   const char *arg,
+	   gint       *result,
+	   GError    **error)
+{
+  gchar *end;
+  glong tmp = strtol (arg, &end, 0);
+
+  errno = 0;
+  
+  if (*arg == '\0' || *end != '\0')
+    {
+      g_set_error (error,
+		   ARG_CONTEXT_ERROR, ARG_CONTEXT_ERROR_BAD_VALUE,
+		   "Cannot parse integer value '%s' for --%s",
+		   arg, arg_name);
+      return FALSE;
+    }
+
+  *result = tmp;
+  if (*result != tmp || errno == ERANGE)
+    {
+      g_set_error (error,
+		   ARG_CONTEXT_ERROR, ARG_CONTEXT_ERROR_BAD_VALUE,
+		   "Integer value '%s' for %s out of range",
+		   arg, arg_name);
+      return FALSE;
+    }
+
+  return TRUE;
+}
+
+void
+arg_context_print_help (ArgContext *context)
+{
+  int j, k;
+  int max_name_len = 0;
+
+  for (j = 0; j < context->tables->len; j++)
+    {
+      ArgDesc *table = context->tables->pdata[j];
+      for (k = 0; table[k].name; k++)
+	max_name_len = MAX (strlen (table[k].name), max_name_len);
+    }
+
+  for (j = 0; j < context->tables->len; j++)
+    {
+      ArgDesc *table = context->tables->pdata[j];
+      for (k = 0; table[k].name; k++)
+	g_print ("  --%-*s %s\n",
+		 max_name_len, table[k].name,
+		 table[k].help ? table[k].help : "");
+    }
+}
+
+gboolean
+arg_context_parse (ArgContext *context,
+		   gint       *argc,
+		   gchar    ***argv,
+		   GError    **error)
+{
+  int i, j, k;
+
+  if (argc && argv)
+    {
+      for (i = 1; i < *argc; i++)
+	{
+	  char *arg;
+
+	  if ((*argv)[i][0] == '-' && (*argv)[i][1] != '-')
+	    {
+	      g_set_error (error,
+			   ARG_CONTEXT_ERROR, ARG_CONTEXT_ERROR_UNKNOWN_OPTION,
+			   "Unknown option %s", (*argv)[i]);
+	      return FALSE;
+	    }
+	  
+	  if (!((*argv)[i][0] == '-' && (*argv)[i][1] == '-'))
+	    continue;
+	  
+	  arg = (*argv)[i] + 2;
+
+	  /* '--' terminates list of arguments */
+	  if (arg == 0)
+	    {
+	      (*argv)[i] = NULL;
+	      break;
+	    }
+	      
+	  for (j = 0; j < context->tables->len; j++)
+	    {
+	      ArgDesc *table = context->tables->pdata[j];
+	      for (k = 0; table[k].name; k++)
+		{
+		  switch (table[k].type)
+		    {
+		    case ARG_STRING:
+		    case ARG_CALLBACK:
+		    case ARG_INT:
+		      {
+			int len = strlen (table[k].name);
+			
+			if (strncmp (arg, table[k].name, len) == 0 &&
+			    (arg[len] == '=' || arg[len] == 0))
+			  {
+			    char *value = NULL;
+
+			    (*argv)[i] = NULL;
+
+			    if (arg[len] == '=')
+			      value = arg + len + 1;
+			    else if (i < *argc - 1)
+			      {
+				value = (*argv)[i + 1];
+				(*argv)[i+1] = NULL;
+				i++;
+			      }
+			    else
+			      value = "";
+
+			    switch (table[k].type)
+			      {
+			      case ARG_STRING:
+				*(gchar **)table[k].location = value;
+				break;
+			      case ARG_INT:
+				if (!parse_int (table[k].name, value,
+						(gint *)table[k].location,
+						error))
+				  return FALSE;
+				break;
+			      case ARG_CALLBACK:
+				(*table[k].callback)(context, table[k].name, value, context->cb_data);
+				break;
+			      default:
+				;
+			      }
+
+			    goto next_arg;
+			  }
+			break;
+		      }
+		    case ARG_BOOL:
+		    case ARG_NOBOOL:
+		      if (strcmp (arg, table[k].name) == 0)
+			{
+			  (*argv)[i] = NULL;
+			  
+			  *(gboolean *)table[k].location = (table[k].type == ARG_BOOL) ? TRUE : FALSE;
+			  goto next_arg;
+			}
+		    }
+		}
+	    }
+	  g_set_error (error,
+		       ARG_CONTEXT_ERROR, ARG_CONTEXT_ERROR_UNKNOWN_OPTION,
+		       "Unknown option --%s",
+		       arg);
+	  return FALSE;
+	  
+	next_arg:
+	  ;
+	}
+	  
+      for (i = 1; i < *argc; i++)
+	{
+	  for (k = i; k < *argc; k++)
+	    if ((*argv)[k] != NULL)
+	      break;
+	  
+	  if (k > i)
+	    {
+	      k -= i;
+	      for (j = i + k; j < *argc; j++)
+		(*argv)[j-k] = (*argv)[j];
+	      *argc -= k;
+	    }
+	}
+    }
+
+  return TRUE;
+}
diff --git a/examples/argcontext.h b/examples/argcontext.h
new file mode 100644
index 00000000..9749c8b2
--- /dev/null
+++ b/examples/argcontext.h
@@ -0,0 +1,76 @@
+/* argcontext.h - Simple command line argument parsing
+ * Copyright 1999, 2003 Red Hat Software
+ *
+ * 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.
+ */
+
+#ifndef __ARG_CONTEXT_H__
+#define __ARG_CONTEXT_H__
+
+#include <glib.h>
+
+G_BEGIN_DECLS
+
+typedef enum 
+{
+  ARG_STRING,
+  ARG_INT,
+  ARG_BOOL,
+  ARG_NOBOOL,
+  ARG_CALLBACK
+} ArgType;
+
+typedef struct _ArgContext ArgContext;
+typedef struct _ArgDesc ArgDesc;
+
+#define ARG_CONTEXT_ERROR arg_context_error_quark ()
+
+typedef enum
+{
+  ARG_CONTEXT_ERROR_UNKNOWN_OPTION,
+  ARG_CONTEXT_ERROR_BAD_VALUE,
+  ARG_CONTEXT_ERROR_FAILED
+} ArgContextError;
+
+typedef void (*ArgFunc) (ArgContext *arg_context,
+			 const char *name,
+			 const char *arg,
+			 gpointer    data);
+
+struct _ArgDesc
+{
+  const char *name;
+  const char *help;
+  ArgType type;
+  gpointer location;
+  ArgFunc callback;
+};
+
+GQuark      arg_context_error_quark (void);
+
+ArgContext *arg_context_new        (gpointer         cb_data);
+void        arg_context_free       (ArgContext      *context);
+void        arg_context_print_help (ArgContext      *context);
+void        arg_context_add_table  (ArgContext      *context,
+				    const ArgDesc   *table);
+gboolean    arg_context_parse      (ArgContext      *context,
+				    gint            *argc,
+				    gchar         ***argv,
+				    GError         **error);
+
+G_END_DECLS
+
+#endif /* __ARG_CONTEXT_H__ */
diff --git a/examples/pangoft2topgm.c b/examples/pangoft2topgm.c
index 257dc8bb..f223f89e 100644
--- a/examples/pangoft2topgm.c
+++ b/examples/pangoft2topgm.c
@@ -24,10 +24,7 @@
 #define BUFSIZE 1024
 #define MALLOCSIZE 1024
 #define DEFAULT_FONT_FAMILY "Sans"
-#define DEFAULT_FONT_SIZE 36
-
-#include <pango/pango.h>
-#include <pango/pangoft2.h>
+#define DEFAULT_FONT_SIZE 18
 
 #include <errno.h>
 #include <stdarg.h>
@@ -35,22 +32,31 @@
 #include <stdio.h>
 #include <string.h>
 
-static char *prog_name;
-static PangoContext *context;
+#include "argcontext.h"
 
-static gboolean opt_display = FALSE;
-static int opt_dpi = 96;
+#include <pango/pango.h>
+#include <pango/pangoft2.h>
 
 #define _MAKE_FONT_NAME(family, size) family " " #size
 #define MAKE_FONT_NAME(family, size) _MAKE_FONT_NAME(family, size)
-static char *opt_font = MAKE_FONT_NAME (DEFAULT_FONT_FAMILY, DEFAULT_FONT_SIZE);
 
-static  PangoDirection opt_dir = PANGO_DIRECTION_LTR;
+static char *prog_name;
+static PangoContext *context;
+
+static char *tmpfile_name;
 static char *outfile_name;
+
+static gboolean opt_display = FALSE;
+static int opt_dpi = 96;
+static char *opt_font = MAKE_FONT_NAME (DEFAULT_FONT_FAMILY, DEFAULT_FONT_SIZE);
+static gboolean opt_header = FALSE;
 static char *opt_output = NULL;
 static int opt_margin = 10;
 static int opt_markup = FALSE;
+static gboolean opt_rtl = FALSE;
+static char *opt_text = NULL;
 static  gboolean opt_waterfall = FALSE;
+static  int opt_width = -1;
 
 static void fail (const char *format, ...)  G_GNUC_PRINTF (1, 2);
 
@@ -70,6 +76,20 @@ fail (const char *format, ...)
   exit (1);
 }
 
+PangoFontDescription *
+get_font_description (void)
+{
+  PangoFontDescription *font_description = pango_font_description_from_string (opt_font);
+  
+  if ((pango_font_description_get_set_fields (font_description) & PANGO_FONT_MASK_FAMILY) == 0)
+    pango_font_description_set_family (font_description, DEFAULT_FONT_FAMILY);
+
+  if ((pango_font_description_get_set_fields (font_description) & PANGO_FONT_MASK_SIZE) == 0)
+    pango_font_description_set_size (font_description, DEFAULT_FONT_SIZE * PANGO_SCALE);
+
+  return font_description;
+}
+
 static PangoLayout *
 make_layout(PangoContext *context,
 	    const char   *text,
@@ -85,26 +105,42 @@ make_layout(PangoContext *context,
   else
     pango_layout_set_text (layout, text, -1);
 
-  font_description = pango_font_description_from_string (opt_font);
-
-  if ((pango_font_description_get_set_fields (font_description) & PANGO_FONT_MASK_FAMILY) == 0)
-    pango_font_description_set_family (font_description, DEFAULT_FONT_FAMILY);
-
+  font_description = get_font_description ();
   if (size > 0)
     pango_font_description_set_size (font_description, size * PANGO_SCALE);
-  else if ((pango_font_description_get_set_fields (font_description) & PANGO_FONT_MASK_SIZE) == 0)
-    pango_font_description_set_size (font_description, DEFAULT_FONT_SIZE * PANGO_SCALE);
     
+  if (opt_width > 0)
+    pango_layout_set_width (layout, (opt_width * opt_dpi * PANGO_SCALE + 32) / 72);
+
   base_dir = pango_context_get_base_dir (context);
   pango_layout_set_alignment (layout,
 			      base_dir == PANGO_DIRECTION_LTR ? PANGO_ALIGN_LEFT : PANGO_ALIGN_RIGHT);
   
   pango_layout_set_font_description (layout, font_description);
+
   pango_font_description_free (font_description);
 
   return layout;
 }
 
+static gchar *
+get_options_string (void)
+{
+  PangoFontDescription *font_description = get_font_description ();
+  gchar *font_name;
+  gchar *result;
+
+  if (opt_waterfall)
+    pango_font_description_unset_fields (font_description, PANGO_FONT_MASK_SIZE);
+
+  font_name = pango_font_description_to_string (font_description);
+  result = g_strdup_printf ("%s: dpi=%d", font_name, opt_dpi);
+  pango_font_description_free (font_description);
+  g_free (font_name);
+
+  return result;
+}
+
 static void
 do_output (PangoContext *context,
 	   const char   *text,
@@ -121,6 +157,24 @@ do_output (PangoContext *context,
   *width = 0;
   *height = 0;
 
+  if (opt_header)
+    {
+      char *options_string = get_options_string ();
+      layout = make_layout (context, options_string, 10);
+      pango_layout_get_extents (layout, NULL, &logical_rect);
+      
+      *width = MAX (*width, PANGO_PIXELS (logical_rect.width));
+      *height += PANGO_PIXELS (logical_rect.height);
+      
+      if (bitmap)
+	pango_ft2_render_layout (bitmap, layout, x, y);
+      
+      y += PANGO_PIXELS (logical_rect.height);
+      
+      g_object_unref (layout);
+      g_free (options_string);
+    }
+  
   if (opt_waterfall)
     {
       start_size = 8;
@@ -153,17 +207,21 @@ do_output (PangoContext *context,
   *height += 2 * opt_margin;
 }
 
-int int_arg (const char *arg_name, const char *arg)
+static void
+show_help (ArgContext *context,
+	   const char *name,
+	   const char *arg,
+	   gpointer    data)
 {
-  char *end;
-  long result = strtol (arg, &end, 0);
-  if (*arg == '\0' || *end != '\0')
-    {
-      fail ("Cannot parse integer value '%s' for %s.",
-	    arg, arg_name);
-    }
-
-  return result;
+  g_print ("%s - An example viewer for the pango ft2 extension\n"
+	   "\n"
+	   "Syntax:\n"
+	   "    %s [options] FILE\n"
+	   "\n"
+	   "Options:\n",
+	   prog_name, prog_name);
+  arg_context_print_help (context);
+  exit (0);
 }
 
 int main(int argc, char *argv[])
@@ -172,9 +230,38 @@ int main(int argc, char *argv[])
   char *text;
   size_t len;
   char *p;
-  int argp;
   PangoFontMap *fontmap;
   GError *error = NULL;
+  ArgContext *arg_context;
+  gboolean do_convert = FALSE;
+  
+  static const ArgDesc args[] = {
+    { "display",    "Show output using ImageMagick",
+      ARG_BOOL,     &opt_display },
+    { "dpi",        "Set the dpi'",
+      ARG_INT,      &opt_dpi },
+    { "font",       "Set the font name",
+      ARG_STRING,   &opt_font },
+    { "header",     "Display the options in the output",
+      ARG_BOOL,     &opt_header },
+    { "help",       "Show this output",
+      ARG_CALLBACK, NULL, show_help, },
+    { "margin",     "Set the margin on the output in pixels",
+      ARG_INT,      &opt_margin },
+    { "markup",     "Interpret contents as Pango markup",
+      ARG_BOOL,     &opt_markup },
+    { "output",     "Name of output file",
+      ARG_STRING,   &opt_output },
+    { "rtl",        "Set base dir to RTL",
+      ARG_BOOL,     &opt_rtl },
+    { "text",       "Text to display (instead of a file)",
+      ARG_STRING,   &opt_text },
+    { "waterfall",  "Create a waterfall display",
+      ARG_BOOL,     &opt_waterfall },
+    { "width",      "Width in points to which to wrap output",
+      ARG_INT,      &opt_width },
+    { NULL }
+  };
 
   prog_name = g_path_get_basename (argv[0]);
   
@@ -183,93 +270,43 @@ int main(int argc, char *argv[])
   if (g_file_test ("./pangorc", G_FILE_TEST_EXISTS))
     putenv ("PANGO_RC_FILE=./pangorc");
   
-  /* Parse command line */
-  argp=1;
-  while(argp < argc && argv[argp][0] == '-')
+  arg_context = arg_context_new (NULL);
+  arg_context_add_table (arg_context, args);
+
+  if (!arg_context_parse (arg_context, &argc, &argv, &error))
+    fail ("%s", error->message);
+  
+  if ((opt_text && argc != 1) ||
+      (!opt_text && argc != 2))
     {
-      char *opt = argv[argp++];
-      if (strcmp(opt, "--help") == 0)
-	{
-	  printf("%s - An example viewer for the pango ft2 extension\n"
-		 "\n"
-		 "Syntax:\n"
-		 "    %s [options] FILE\n"
-		 "\n"
-		 "Options:\n"
- 		 "    --display    Show output using ImageMagick rather than writing to a file.\n"
-		 "    --dpi d      Set the dpi.Default is '%d'.\n"
-		 "    --font       Set the font name. Default is '%s'.\n"
-		 "    --margin m   Set the margin on the output in pixels. Default is %d.\n"
-		 "    --markup     Interpret contents as Pango markup.\n"
- 		 "    --output f   Name of output file [short form, -o].\n"
-		 "    --rtl        Set base dir to RTL. Default is LTR.\n"
-		 "    --waterfall  Create a waterfall display."
-		 "    --width      Width of drawing window. Default is 500.\n",
-		 prog_name, prog_name, opt_dpi, opt_font, opt_margin);
-	  exit(0);
-	}
-      if (strcmp(opt, "--display") == 0)
-	{
-	  opt_display = TRUE;
-	  continue;
-	}
-      if (strcmp(opt, "--dpi") == 0)
-	{
-	  opt_dpi = int_arg("--dpi", argv[argp++]);
-	  continue;
-	}
-      if (strcmp(opt, "--font") == 0)
-	{
-	  opt_font = argv[argp++];
-	  continue;
-	}
-      if (strcmp(opt, "--margin") == 0)
-	{
-	  opt_margin = int_arg("--margin", argv[argp++]);
-	  continue;
-	}
-      if (strcmp(opt, "--markup") == 0)
-	{
-	  opt_markup = TRUE;
-	  continue;
-	}
-      if (strcmp(opt, "--output") == 0 ||
-	  strcmp(opt, "-o") == 0)
-	{
-	  opt_output = argv[argp++];
-	  continue;
-	}
-      if (strcmp(opt, "--waterfall") == 0)
-	{
-	  opt_waterfall = TRUE;
-	  continue;
-	}
-      if (strcmp(opt, "--rtl") == 0)
-	{
-	  opt_dir = PANGO_DIRECTION_RTL;
-	  continue;
-	}
-      fail ("Unknown option %s!\n", opt);
+      if (opt_text && argc == 2)
+	fail ("When specifying --text, no file should be given");
+	
+      g_printerr ("Usage: %s [options] FILE\n", prog_name);
+      exit (1);
     }
+
   if (!opt_display && !opt_output)
     {
       g_printerr ("%s: --output not specified, assuming --display\n", prog_name);
       opt_display = TRUE;
     }
 
-  if (argp + 1 != argc)
+  /* Get the text
+   */
+  if (opt_text)
     {
-      g_printerr ("Usage: %s [options] FILE\n", prog_name);
-      exit (1);
+      text = g_strdup (opt_text);
+      len = strlen (text);
     }
-
-  /* Get the text in the supplied file
-   */
-  if (!g_file_get_contents (argv[argp++], &text, &len, &error))
-    fail ("%s\n", error->message);
-  if (!g_utf8_validate (text, len, NULL))
-    fail ("Text is not valid UTF-8");
-
+  else
+    {
+      if (!g_file_get_contents (argv[1], &text, &len, &error))
+	fail ("%s\n", error->message);
+      if (!g_utf8_validate (text, len, NULL))
+	fail ("Text is not valid UTF-8");
+    }
+  
   /* Strip trailing whitespace
    */
   p = text + len;
@@ -292,7 +329,13 @@ int main(int argc, char *argv[])
 
   if (opt_output)
     {
-      outfile_name = opt_output;
+      if (!(g_str_has_suffix (opt_output, ".pgm") ||
+	    g_str_has_suffix (opt_output, ".PGM")))
+	do_convert = TRUE;
+    }
+
+  if (opt_output && !do_convert)
+    {
       outfile = fopen (opt_output, "wb");
 
       if (!outfile)
@@ -302,7 +345,7 @@ int main(int argc, char *argv[])
   else				/* --display */
     {
       /* This may need to be G_OS_UNIX guarded for fdopen */
-      int fd = g_file_open_tmp ("pangoft2pgmXXXXXX", &outfile_name, &error);
+      int fd = g_file_open_tmp ("pangoft2pgmXXXXXX", &tmpfile_name, &error);
       if (fd == 1)
 	fail ("Cannot open temporary file: %s\n", error->message);
       outfile = fdopen (fd, "wb");
@@ -315,7 +358,8 @@ int main(int argc, char *argv[])
   context = pango_ft2_font_map_create_context (PANGO_FT2_FONT_MAP (fontmap));
 
   pango_context_set_language (context, pango_language_from_string ("en_US"));
-  pango_context_set_base_dir (context, opt_dir);
+  pango_context_set_base_dir (context,
+			      opt_rtl ? PANGO_DIRECTION_RTL : PANGO_DIRECTION_LTR);
 
   /* Write contents as pgm file */
   {
@@ -333,7 +377,7 @@ int main(int argc, char *argv[])
       bitmap.num_grays = 256;
       bitmap.pixel_mode = ft_pixel_mode_grays;
       memset (buf, 0x00, bitmap.pitch * bitmap.rows);
-	  
+
       do_output (context, text, &bitmap, &width, &height);
       
       /* Invert bitmap to get black text on white background */
@@ -358,17 +402,47 @@ int main(int argc, char *argv[])
       if (fclose(outfile) == EOF)
 	fail ("Error writing output file: %s\n", g_strerror (errno));
 
+      /* Convert to a different format, if necessary */
+      if (do_convert)
+	{
+	  int exit_status;
+	  
+	  gchar *command = g_strdup_printf ("convert %s %s",
+					    tmpfile_name,
+					    opt_output);
+	  if (!g_spawn_command_line_sync (command, NULL, NULL, &exit_status, &error))
+	    fail ("When running ImageMagick 'convert' command: %s\n",
+		  error->message);
+
+	  if (tmpfile_name)
+	    {
+	      remove (tmpfile_name);
+	      tmpfile_name = NULL;
+	    }
+	  
+	  if (exit_status)
+	    exit (1);
+	}
+
       if (opt_display)
 	{
 	  int exit_status;
-	  gchar *command = g_strdup_printf ("display %s", outfile_name);
+	  gchar *title = get_options_string ();
+	  gchar *title_quoted = g_shell_quote (title);
+	  
+	  gchar *command = g_strdup_printf ("display -title %s %s",
+					    title_quoted,
+					    opt_output ? opt_output: tmpfile_name);
 	  if (!g_spawn_command_line_sync (command, NULL, NULL, &exit_status, &error))
 	    fail ("When running ImageMagick 'display' command: %s\n",
 		  error->message);
 
 	  g_free (command);
-	  if (!opt_output)
-	    remove (outfile_name);
+	  g_free (title);
+	  g_free (title_quoted);
+	  
+	  if (tmpfile_name)
+	    remove (tmpfile_name);
 	  
 	  if (exit_status)
 	    exit (1);
diff --git a/examples/renderdemo.c b/examples/renderdemo.c
index 257dc8bb..f223f89e 100644
--- a/examples/renderdemo.c
+++ b/examples/renderdemo.c
@@ -24,10 +24,7 @@
 #define BUFSIZE 1024
 #define MALLOCSIZE 1024
 #define DEFAULT_FONT_FAMILY "Sans"
-#define DEFAULT_FONT_SIZE 36
-
-#include <pango/pango.h>
-#include <pango/pangoft2.h>
+#define DEFAULT_FONT_SIZE 18
 
 #include <errno.h>
 #include <stdarg.h>
@@ -35,22 +32,31 @@
 #include <stdio.h>
 #include <string.h>
 
-static char *prog_name;
-static PangoContext *context;
+#include "argcontext.h"
 
-static gboolean opt_display = FALSE;
-static int opt_dpi = 96;
+#include <pango/pango.h>
+#include <pango/pangoft2.h>
 
 #define _MAKE_FONT_NAME(family, size) family " " #size
 #define MAKE_FONT_NAME(family, size) _MAKE_FONT_NAME(family, size)
-static char *opt_font = MAKE_FONT_NAME (DEFAULT_FONT_FAMILY, DEFAULT_FONT_SIZE);
 
-static  PangoDirection opt_dir = PANGO_DIRECTION_LTR;
+static char *prog_name;
+static PangoContext *context;
+
+static char *tmpfile_name;
 static char *outfile_name;
+
+static gboolean opt_display = FALSE;
+static int opt_dpi = 96;
+static char *opt_font = MAKE_FONT_NAME (DEFAULT_FONT_FAMILY, DEFAULT_FONT_SIZE);
+static gboolean opt_header = FALSE;
 static char *opt_output = NULL;
 static int opt_margin = 10;
 static int opt_markup = FALSE;
+static gboolean opt_rtl = FALSE;
+static char *opt_text = NULL;
 static  gboolean opt_waterfall = FALSE;
+static  int opt_width = -1;
 
 static void fail (const char *format, ...)  G_GNUC_PRINTF (1, 2);
 
@@ -70,6 +76,20 @@ fail (const char *format, ...)
   exit (1);
 }
 
+PangoFontDescription *
+get_font_description (void)
+{
+  PangoFontDescription *font_description = pango_font_description_from_string (opt_font);
+  
+  if ((pango_font_description_get_set_fields (font_description) & PANGO_FONT_MASK_FAMILY) == 0)
+    pango_font_description_set_family (font_description, DEFAULT_FONT_FAMILY);
+
+  if ((pango_font_description_get_set_fields (font_description) & PANGO_FONT_MASK_SIZE) == 0)
+    pango_font_description_set_size (font_description, DEFAULT_FONT_SIZE * PANGO_SCALE);
+
+  return font_description;
+}
+
 static PangoLayout *
 make_layout(PangoContext *context,
 	    const char   *text,
@@ -85,26 +105,42 @@ make_layout(PangoContext *context,
   else
     pango_layout_set_text (layout, text, -1);
 
-  font_description = pango_font_description_from_string (opt_font);
-
-  if ((pango_font_description_get_set_fields (font_description) & PANGO_FONT_MASK_FAMILY) == 0)
-    pango_font_description_set_family (font_description, DEFAULT_FONT_FAMILY);
-
+  font_description = get_font_description ();
   if (size > 0)
     pango_font_description_set_size (font_description, size * PANGO_SCALE);
-  else if ((pango_font_description_get_set_fields (font_description) & PANGO_FONT_MASK_SIZE) == 0)
-    pango_font_description_set_size (font_description, DEFAULT_FONT_SIZE * PANGO_SCALE);
     
+  if (opt_width > 0)
+    pango_layout_set_width (layout, (opt_width * opt_dpi * PANGO_SCALE + 32) / 72);
+
   base_dir = pango_context_get_base_dir (context);
   pango_layout_set_alignment (layout,
 			      base_dir == PANGO_DIRECTION_LTR ? PANGO_ALIGN_LEFT : PANGO_ALIGN_RIGHT);
   
   pango_layout_set_font_description (layout, font_description);
+
   pango_font_description_free (font_description);
 
   return layout;
 }
 
+static gchar *
+get_options_string (void)
+{
+  PangoFontDescription *font_description = get_font_description ();
+  gchar *font_name;
+  gchar *result;
+
+  if (opt_waterfall)
+    pango_font_description_unset_fields (font_description, PANGO_FONT_MASK_SIZE);
+
+  font_name = pango_font_description_to_string (font_description);
+  result = g_strdup_printf ("%s: dpi=%d", font_name, opt_dpi);
+  pango_font_description_free (font_description);
+  g_free (font_name);
+
+  return result;
+}
+
 static void
 do_output (PangoContext *context,
 	   const char   *text,
@@ -121,6 +157,24 @@ do_output (PangoContext *context,
   *width = 0;
   *height = 0;
 
+  if (opt_header)
+    {
+      char *options_string = get_options_string ();
+      layout = make_layout (context, options_string, 10);
+      pango_layout_get_extents (layout, NULL, &logical_rect);
+      
+      *width = MAX (*width, PANGO_PIXELS (logical_rect.width));
+      *height += PANGO_PIXELS (logical_rect.height);
+      
+      if (bitmap)
+	pango_ft2_render_layout (bitmap, layout, x, y);
+      
+      y += PANGO_PIXELS (logical_rect.height);
+      
+      g_object_unref (layout);
+      g_free (options_string);
+    }
+  
   if (opt_waterfall)
     {
       start_size = 8;
@@ -153,17 +207,21 @@ do_output (PangoContext *context,
   *height += 2 * opt_margin;
 }
 
-int int_arg (const char *arg_name, const char *arg)
+static void
+show_help (ArgContext *context,
+	   const char *name,
+	   const char *arg,
+	   gpointer    data)
 {
-  char *end;
-  long result = strtol (arg, &end, 0);
-  if (*arg == '\0' || *end != '\0')
-    {
-      fail ("Cannot parse integer value '%s' for %s.",
-	    arg, arg_name);
-    }
-
-  return result;
+  g_print ("%s - An example viewer for the pango ft2 extension\n"
+	   "\n"
+	   "Syntax:\n"
+	   "    %s [options] FILE\n"
+	   "\n"
+	   "Options:\n",
+	   prog_name, prog_name);
+  arg_context_print_help (context);
+  exit (0);
 }
 
 int main(int argc, char *argv[])
@@ -172,9 +230,38 @@ int main(int argc, char *argv[])
   char *text;
   size_t len;
   char *p;
-  int argp;
   PangoFontMap *fontmap;
   GError *error = NULL;
+  ArgContext *arg_context;
+  gboolean do_convert = FALSE;
+  
+  static const ArgDesc args[] = {
+    { "display",    "Show output using ImageMagick",
+      ARG_BOOL,     &opt_display },
+    { "dpi",        "Set the dpi'",
+      ARG_INT,      &opt_dpi },
+    { "font",       "Set the font name",
+      ARG_STRING,   &opt_font },
+    { "header",     "Display the options in the output",
+      ARG_BOOL,     &opt_header },
+    { "help",       "Show this output",
+      ARG_CALLBACK, NULL, show_help, },
+    { "margin",     "Set the margin on the output in pixels",
+      ARG_INT,      &opt_margin },
+    { "markup",     "Interpret contents as Pango markup",
+      ARG_BOOL,     &opt_markup },
+    { "output",     "Name of output file",
+      ARG_STRING,   &opt_output },
+    { "rtl",        "Set base dir to RTL",
+      ARG_BOOL,     &opt_rtl },
+    { "text",       "Text to display (instead of a file)",
+      ARG_STRING,   &opt_text },
+    { "waterfall",  "Create a waterfall display",
+      ARG_BOOL,     &opt_waterfall },
+    { "width",      "Width in points to which to wrap output",
+      ARG_INT,      &opt_width },
+    { NULL }
+  };
 
   prog_name = g_path_get_basename (argv[0]);
   
@@ -183,93 +270,43 @@ int main(int argc, char *argv[])
   if (g_file_test ("./pangorc", G_FILE_TEST_EXISTS))
     putenv ("PANGO_RC_FILE=./pangorc");
   
-  /* Parse command line */
-  argp=1;
-  while(argp < argc && argv[argp][0] == '-')
+  arg_context = arg_context_new (NULL);
+  arg_context_add_table (arg_context, args);
+
+  if (!arg_context_parse (arg_context, &argc, &argv, &error))
+    fail ("%s", error->message);
+  
+  if ((opt_text && argc != 1) ||
+      (!opt_text && argc != 2))
     {
-      char *opt = argv[argp++];
-      if (strcmp(opt, "--help") == 0)
-	{
-	  printf("%s - An example viewer for the pango ft2 extension\n"
-		 "\n"
-		 "Syntax:\n"
-		 "    %s [options] FILE\n"
-		 "\n"
-		 "Options:\n"
- 		 "    --display    Show output using ImageMagick rather than writing to a file.\n"
-		 "    --dpi d      Set the dpi.Default is '%d'.\n"
-		 "    --font       Set the font name. Default is '%s'.\n"
-		 "    --margin m   Set the margin on the output in pixels. Default is %d.\n"
-		 "    --markup     Interpret contents as Pango markup.\n"
- 		 "    --output f   Name of output file [short form, -o].\n"
-		 "    --rtl        Set base dir to RTL. Default is LTR.\n"
-		 "    --waterfall  Create a waterfall display."
-		 "    --width      Width of drawing window. Default is 500.\n",
-		 prog_name, prog_name, opt_dpi, opt_font, opt_margin);
-	  exit(0);
-	}
-      if (strcmp(opt, "--display") == 0)
-	{
-	  opt_display = TRUE;
-	  continue;
-	}
-      if (strcmp(opt, "--dpi") == 0)
-	{
-	  opt_dpi = int_arg("--dpi", argv[argp++]);
-	  continue;
-	}
-      if (strcmp(opt, "--font") == 0)
-	{
-	  opt_font = argv[argp++];
-	  continue;
-	}
-      if (strcmp(opt, "--margin") == 0)
-	{
-	  opt_margin = int_arg("--margin", argv[argp++]);
-	  continue;
-	}
-      if (strcmp(opt, "--markup") == 0)
-	{
-	  opt_markup = TRUE;
-	  continue;
-	}
-      if (strcmp(opt, "--output") == 0 ||
-	  strcmp(opt, "-o") == 0)
-	{
-	  opt_output = argv[argp++];
-	  continue;
-	}
-      if (strcmp(opt, "--waterfall") == 0)
-	{
-	  opt_waterfall = TRUE;
-	  continue;
-	}
-      if (strcmp(opt, "--rtl") == 0)
-	{
-	  opt_dir = PANGO_DIRECTION_RTL;
-	  continue;
-	}
-      fail ("Unknown option %s!\n", opt);
+      if (opt_text && argc == 2)
+	fail ("When specifying --text, no file should be given");
+	
+      g_printerr ("Usage: %s [options] FILE\n", prog_name);
+      exit (1);
     }
+
   if (!opt_display && !opt_output)
     {
       g_printerr ("%s: --output not specified, assuming --display\n", prog_name);
       opt_display = TRUE;
     }
 
-  if (argp + 1 != argc)
+  /* Get the text
+   */
+  if (opt_text)
     {
-      g_printerr ("Usage: %s [options] FILE\n", prog_name);
-      exit (1);
+      text = g_strdup (opt_text);
+      len = strlen (text);
     }
-
-  /* Get the text in the supplied file
-   */
-  if (!g_file_get_contents (argv[argp++], &text, &len, &error))
-    fail ("%s\n", error->message);
-  if (!g_utf8_validate (text, len, NULL))
-    fail ("Text is not valid UTF-8");
-
+  else
+    {
+      if (!g_file_get_contents (argv[1], &text, &len, &error))
+	fail ("%s\n", error->message);
+      if (!g_utf8_validate (text, len, NULL))
+	fail ("Text is not valid UTF-8");
+    }
+  
   /* Strip trailing whitespace
    */
   p = text + len;
@@ -292,7 +329,13 @@ int main(int argc, char *argv[])
 
   if (opt_output)
     {
-      outfile_name = opt_output;
+      if (!(g_str_has_suffix (opt_output, ".pgm") ||
+	    g_str_has_suffix (opt_output, ".PGM")))
+	do_convert = TRUE;
+    }
+
+  if (opt_output && !do_convert)
+    {
       outfile = fopen (opt_output, "wb");
 
       if (!outfile)
@@ -302,7 +345,7 @@ int main(int argc, char *argv[])
   else				/* --display */
     {
       /* This may need to be G_OS_UNIX guarded for fdopen */
-      int fd = g_file_open_tmp ("pangoft2pgmXXXXXX", &outfile_name, &error);
+      int fd = g_file_open_tmp ("pangoft2pgmXXXXXX", &tmpfile_name, &error);
       if (fd == 1)
 	fail ("Cannot open temporary file: %s\n", error->message);
       outfile = fdopen (fd, "wb");
@@ -315,7 +358,8 @@ int main(int argc, char *argv[])
   context = pango_ft2_font_map_create_context (PANGO_FT2_FONT_MAP (fontmap));
 
   pango_context_set_language (context, pango_language_from_string ("en_US"));
-  pango_context_set_base_dir (context, opt_dir);
+  pango_context_set_base_dir (context,
+			      opt_rtl ? PANGO_DIRECTION_RTL : PANGO_DIRECTION_LTR);
 
   /* Write contents as pgm file */
   {
@@ -333,7 +377,7 @@ int main(int argc, char *argv[])
       bitmap.num_grays = 256;
       bitmap.pixel_mode = ft_pixel_mode_grays;
       memset (buf, 0x00, bitmap.pitch * bitmap.rows);
-	  
+
       do_output (context, text, &bitmap, &width, &height);
       
       /* Invert bitmap to get black text on white background */
@@ -358,17 +402,47 @@ int main(int argc, char *argv[])
       if (fclose(outfile) == EOF)
 	fail ("Error writing output file: %s\n", g_strerror (errno));
 
+      /* Convert to a different format, if necessary */
+      if (do_convert)
+	{
+	  int exit_status;
+	  
+	  gchar *command = g_strdup_printf ("convert %s %s",
+					    tmpfile_name,
+					    opt_output);
+	  if (!g_spawn_command_line_sync (command, NULL, NULL, &exit_status, &error))
+	    fail ("When running ImageMagick 'convert' command: %s\n",
+		  error->message);
+
+	  if (tmpfile_name)
+	    {
+	      remove (tmpfile_name);
+	      tmpfile_name = NULL;
+	    }
+	  
+	  if (exit_status)
+	    exit (1);
+	}
+
       if (opt_display)
 	{
 	  int exit_status;
-	  gchar *command = g_strdup_printf ("display %s", outfile_name);
+	  gchar *title = get_options_string ();
+	  gchar *title_quoted = g_shell_quote (title);
+	  
+	  gchar *command = g_strdup_printf ("display -title %s %s",
+					    title_quoted,
+					    opt_output ? opt_output: tmpfile_name);
 	  if (!g_spawn_command_line_sync (command, NULL, NULL, &exit_status, &error))
 	    fail ("When running ImageMagick 'display' command: %s\n",
 		  error->message);
 
 	  g_free (command);
-	  if (!opt_output)
-	    remove (outfile_name);
+	  g_free (title);
+	  g_free (title_quoted);
+	  
+	  if (tmpfile_name)
+	    remove (tmpfile_name);
 	  
 	  if (exit_status)
 	    exit (1);