+ | Not_found -> default_port
+ | Failure "int_of_string" ->
+ prerr_endline "Warning: invalid port, reverting to default";
+ default_port
+;;
+
+let (html_preamble, html_postamble) =
+ ((fun uri ->
+ (sprintf
+"<html>
+<head>
+ <title>Proof-Checking %s</title>
+</head>
+<body bgcolor=\"white\">
+<h1>Proof-Checking %s:</h1>
+"
+ uri uri)),
+("<h1>Done.</h1>
+</body>
+</html>
+END
+"))
+;;
+
+let bad_request outchan =
+ printf "INVALID REQUEST !!!!!\n\n";
+ flush stdout;
+ Http_daemon.respond_error ~status:(`Client_error `Bad_request) outchan;
+ flush outchan
+;;
+
+let usage_string =
+"
+<html>
+ <head>
+ <title>ProofChecker's help message</title>
+ </head>
+ <body>
+ <h1>ProofChecker</h1>
+ <h2>Usage</h2>
+ <p>
+ Usage: <kbd>http://hostname:proofcheckerport/</kbd><em>command</em>
+ </p>
+ <p>
+ Available commands:
+ </p>
+ <p>
+ <b><kbd>help</kbd></b><br />
+ display this help message
+ </p>
+ <p>
+ <b><kbd>proofCheck?uri=uri</kbd></b><br />
+ proof-checks the object whose URI is specified by <em>uri</em>
+ </p>
+ </body>
+</html>
+"