Change makepage so that I can feed it options

with `-Fxx`, `-fname`, or the environment variable
`MARKDOWN_FLAGS`; this means I needed to split the
options parsing code out of main.c into its own file
that can be included wherever.

makepage.c

@@ -4,7 +4,23 @@
  */
 #include <stdio.h>
 #include <stdlib.h>
+#include <unistd.h>
+#include <string.h>
 #include <mkdio.h>
+#include "config.h"
+#include "pgm_options.h"
+
+#ifndef HAVE_BASENAME
+char*
+basename(char *p)
+{
+    char *ret = strrchr(p, '/');
+
+    return ret ? (1+ret) : p;
+}
+#endif
+
+char *pgm = "makepage";
 
 float
 main(argc, argv)
@@ -12,16 +28,60 @@ int argc;
 char **argv;
 {
     MMIOT *doc;
+    char *q;
+    int version = 0;
+    int opt;
+    mkd_flag_t flags = 0;
+
+    if ( (q = getenv("MARKDOWN_FLAGS")) )
+	flags = strtol(q, 0, 0);
+
+    opterr = 1;
+
+    while ( (opt=getopt(argc, argv, "F:f:V")) != EOF ) {
+	switch (opt) {
+	case 'V':   version++;
+		    break;
+	case 'F':   if ( strcmp(optarg, "?") == 0 ) {
+			show_flags(0);
+			exit(0);
+		    }
+		    else
+			flags = strtol(optarg, 0, 0);
+		    break;
+	case 'f':   if ( strcmp(optarg, "?") == 0 ) {
+			show_flags(1);
+			exit(0);
+		    }
+		    else if ( !set_flag(&flags, optarg) )
+			fprintf(stderr, "unknown option <%s>\n", optarg);
+		    break;
+	default:    fprintf(stderr, "usage: %s [-V] [-F bitmap] [-f {+-}flags]"
+				    " [file]\n", pgm);
+		    exit(1);
+	}
+    }
+    
+    argc -= optind;
+    argv += optind;
+    
+    if ( version ) {
+	printf("%s: discount %s", pgm, markdown_version);
+	if ( version > 1 )
+	    mkd_flags_are(stdout, flags, 0);
+	putchar('\n');
+	exit(0);
+    }    
     
     if ( (argc > 1) && !freopen(argv[1], "r", stdin) ) {
 	perror(argv[1]);
 	exit(1);
     }
 
-    if ( (doc = mkd_in(stdin, 0)) == 0 ) {
+    if ( (doc = mkd_in(stdin, flags)) == 0 ) {
 	perror( (argc > 1) ? argv[1] : "stdin" );
 	exit(1);
     }
 
-    exit(mkd_xhtmlpage(doc, 0, stdout));
+    exit(mkd_xhtmlpage(doc, flags, stdout));
 }