Steady progress

Still trying to figure out FastCGI.

At least I've finally implemented the JSON-RPC handler.

1 files changed, 650 insertions, 34 deletions

diff --git a/demo-json-rpc-server.c b/demo-json-rpc-server.c
index 09f6002..6be6b3e 100644
--- a/demo-json-rpc-server.c
+++ b/demo-json-rpc-server.c
@@ -66,6 +66,45 @@ msg_unpacker_u32 (struct msg_unpacker *self, uint32_t *value)
 
 #undef UNPACKER_INT_BEGIN
 
+// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
+
+// "msg_writer" should be rewritten on top of this
+
+static void
+str_pack_u8 (struct str *self, uint8_t x)
+{
+	str_append_data (self, &x, 1);
+}
+
+static void
+str_pack_u16 (struct str *self, uint64_t x)
+{
+	uint8_t tmp[2] = { x >> 8, x };
+	str_append_data (self, tmp, sizeof tmp);
+}
+
+static void
+str_pack_u32 (struct str *self, uint32_t x)
+{
+	uint32_t u = x;
+	uint8_t tmp[4] = { u >> 24, u >> 16, u >> 8, u };
+	str_append_data (self, tmp, sizeof tmp);
+}
+
+static void
+str_pack_i32 (struct str *self, int32_t x)
+{
+	str_pack_u32 (self, (uint32_t) x);
+}
+
+static void
+str_pack_u64 (struct str *self, uint64_t x)
+{
+	uint8_t tmp[8] =
+		{ x >> 56, x >> 48, x >> 40, x >> 32, x >> 24, x >> 16, x >> 8, x };
+	str_append_data (self, tmp, sizeof tmp);
+}
+
 // --- libev helpers -----------------------------------------------------------
 
 static bool
@@ -312,7 +351,7 @@ fcgi_nv_parser_free (struct fcgi_nv_parser *self)
 }
 
 static void
-fcgi_nv_parser_push (struct fcgi_nv_parser *self, void *data, size_t len)
+fcgi_nv_parser_push (struct fcgi_nv_parser *self, const void *data, size_t len)
 {
 	// This could be optimized significantly; I'm not even trying
 	str_append_data (&self->input, data, len);
@@ -402,7 +441,38 @@ fcgi_nv_parser_push (struct fcgi_nv_parser *self, void *data, size_t len)
 
 // - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
 
-// TODO
+static void
+fcgi_nv_convert_len (size_t len, struct str *output)
+{
+	if (len < 0x80)
+		str_pack_u8 (output, len);
+	else
+	{
+		len |= (uint32_t) 1 << 31;
+		str_pack_u32 (output, len);
+	}
+}
+
+static void
+fcgi_nv_convert (struct str_map *map, struct str *output)
+{
+	struct str_map_iter iter;
+	str_map_iter_init (&iter, map);
+	while (str_map_iter_next (&iter))
+	{
+		const char *name  = iter.link->key;
+		const char *value = iter.link->data;
+		size_t name_len   = iter.link->key_length;
+		size_t value_len  = strlen (value);
+
+		fcgi_nv_convert_len (name_len,  output);
+		fcgi_nv_convert_len (value_len, output);
+		str_append_data (output, name,  name_len);
+		str_append_data (output, value, value_len);
+	}
+}
+
+// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
 
 enum fcgi_request_state
 {
@@ -413,14 +483,17 @@ enum fcgi_request_state
 struct fcgi_request
 {
 	struct fcgi_muxer *muxer;           ///< The parent muxer
-
 	uint16_t request_id;                ///< The ID of this request
+	uint8_t flags;                      ///< Request flags
+
 	enum fcgi_request_state state;      ///< Parsing state
 	struct str_map headers;             ///< Headers
 	struct fcgi_nv_parser hdr_parser;   ///< Header parser
-};
 
-// TODO
+	struct str output_buffer;           ///< Output buffer
+
+	void *handler_data;                 ///< Handler data
+};
 
 struct fcgi_muxer
 {
@@ -429,14 +502,302 @@ struct fcgi_muxer
 	/// Requests assigned to request IDs
 	// TODO: allocate this dynamically
 	struct fcgi_request *requests[1 << 16];
+
+	void (*write_cb) (void *user_data, const void *data, size_t len);
+	void (*close_cb) (void *user_data);
+
+	void *(*request_start_cb) (void *user_data, struct fcgi_request *request);
+	void (*request_push_cb) (void *handler_data, const void *data, size_t len);
+	void (*request_destroy_cb) (void *handler_data);
+
+	void *user_data;                    ///< User data for callbacks
 };
 
 static void
+fcgi_muxer_send (struct fcgi_muxer *self,
+	enum fcgi_type type, uint16_t request_id, const void *data, size_t len)
+{
+	hard_assert (len <= UINT16_MAX);
+
+	struct str message;
+	str_init (&message);
+
+	str_pack_u8  (&message, FCGI_VERSION_1);
+	str_pack_u8  (&message, type);
+	str_pack_u16 (&message, request_id);
+	str_pack_u16 (&message, len);  // content length
+	str_pack_u8  (&message, 0);    // padding length
+
+	str_append_data (&message, data, len);
+
+	// XXX: we should probably have another write_cb that assumes ownership
+	self->write_cb (self->user_data, message.str, message.len);
+	str_free (&message);
+}
+
+static void
+fcgi_muxer_send_end_request (struct fcgi_muxer *self, uint16_t request_id,
+	uint32_t app_status, enum fcgi_protocol_status protocol_status)
+{
+	uint8_t content[8] = { app_status >> 24, app_status >> 16,
+		app_status << 8, app_status, protocol_status };
+	fcgi_muxer_send (self, FCGI_END_REQUEST, request_id,
+		content, sizeof content);
+}
+
+// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
+
+static void
+fcgi_request_init (struct fcgi_request *self)
+{
+	memset (self, 0, sizeof *self);
+
+	str_map_init (&self->headers);
+	self->headers.free = free;
+
+	fcgi_nv_parser_init (&self->hdr_parser);
+	self->hdr_parser.output = &self->headers;
+}
+
+static void
+fcgi_request_free (struct fcgi_request *self)
+{
+	str_map_free (&self->headers);
+	fcgi_nv_parser_free (&self->hdr_parser);
+}
+
+static void
+fcgi_request_push_params
+	(struct fcgi_request *self, const void *data, size_t len)
+{
+	if (self->state != FCGI_REQUEST_PARAMS)
+	{
+		// TODO: probably reject the request
+		return;
+	}
+
+	if (len)
+		fcgi_nv_parser_push (&self->hdr_parser, data, len);
+	else
+	{
+		// TODO: probably check the state of the header parser
+		// TODO: request_start() can return false, end the request here?
+		self->handler_data = self->muxer->request_start_cb
+			(self->muxer->user_data, self);
+		self->state = FCGI_REQUEST_STDIN;
+	}
+}
+
+static void
+fcgi_request_push_stdin
+	(struct fcgi_request *self, const void *data, size_t len)
+{
+	if (self->state != FCGI_REQUEST_STDIN)
+	{
+		// TODO: probably reject the request
+		return;
+	}
+
+	self->muxer->request_push_cb (self->handler_data, data, len);
+}
+
+static void
+fcgi_request_flush (struct fcgi_request *self)
+{
+	if (!self->output_buffer.len)
+		return;
+
+	fcgi_muxer_send (self->muxer, FCGI_STDOUT, self->request_id,
+		self->output_buffer.str, self->output_buffer.len);
+	str_reset (&self->output_buffer);
+}
+
+static void
+fcgi_request_write (struct fcgi_request *self, const void *data, size_t len)
+{
+	// We're buffering the output and splitting it into messages
+	bool need_flush = true;
+	while (len)
+	{
+		size_t to_write = UINT16_MAX - self->output_buffer.len;
+		if (to_write > len)
+		{
+			to_write = len;
+			need_flush = false;
+		}
+
+		str_append_data (&self->output_buffer, data, to_write);
+		data = (uint8_t *) data + to_write;
+		len -= to_write;
+
+		if (need_flush)
+			fcgi_request_flush (self);
+	}
+}
+
+// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
+
+typedef void (*fcgi_muxer_handler_fn)
+	(struct fcgi_muxer *, const struct fcgi_parser *);
+
+static void
+fcgi_muxer_on_get_values
+	(struct fcgi_muxer *self, const struct fcgi_parser *parser)
+{
+	struct str_map values;    str_map_init (&values);    values.free   = free;
+	struct str_map response;  str_map_init (&response);  response.free = free;
+
+	struct fcgi_nv_parser nv_parser;
+	fcgi_nv_parser_init (&nv_parser);
+	nv_parser.output = &values;
+
+	fcgi_nv_parser_push (&nv_parser, parser->content.str, parser->content.len);
+
+	struct str_map_iter iter;
+	str_map_iter_init (&iter, &values);
+	while (str_map_iter_next (&iter))
+	{
+		const char *key = iter.link->key;
+
+		// TODO: if (!strcmp (key, FCGI_MAX_CONNS))
+		// TODO: if (!strcmp (key, FCGI_MAX_REQS))
+
+		if (!strcmp (key, FCGI_MPXS_CONNS))
+			str_map_set (&response, key, xstrdup ("1"));
+	}
+
+	struct str content;
+	str_init (&content);
+	fcgi_nv_convert (&response, &content);
+	fcgi_muxer_send (self, FCGI_GET_VALUES_RESULT, parser->request_id,
+		content.str, content.len);
+	str_free (&content);
+
+	str_map_free (&values);
+	str_map_free (&response);
+}
+
+static void
+fcgi_muxer_on_begin_request
+	(struct fcgi_muxer *self, const struct fcgi_parser *parser)
+{
+	struct msg_unpacker unpacker;
+	msg_unpacker_init (&unpacker, parser->content.str, parser->content.len);
+
+	uint16_t role;
+	uint8_t flags;
+	bool success = true;
+	success &= msg_unpacker_u16 (&unpacker, &role);
+	success &= msg_unpacker_u8 (&unpacker, &flags);
+	// Ignoring 5 reserved bytes
+
+	if (!success)
+	{
+		print_debug ("FastCGI: ignoring invalid %s message",
+			STRINGIFY (FCGI_BEGIN_REQUEST));
+		return;
+	}
+
+	if (role != FCGI_RESPONDER)
+	{
+		fcgi_muxer_send_end_request (self,
+			parser->request_id, 0, FCGI_UNKNOWN_ROLE);
+		return;
+	}
+
+	struct fcgi_request *request = self->requests[parser->request_id];
+	if (request)
+	{
+		// TODO: fail
+		return;
+	}
+
+	request = xcalloc (1, sizeof *request);
+	fcgi_request_init (request);
+	request->muxer = self;
+	request->request_id = parser->request_id;
+	request->flags = flags;
+
+	self->requests[parser->request_id] = request;
+}
+
+static void
+fcgi_muxer_on_abort_request
+	(struct fcgi_muxer *self, const struct fcgi_parser *parser)
+{
+	struct fcgi_request *request = self->requests[parser->request_id];
+	if (!request)
+	{
+		print_debug ("FastCGI: received %s for an unknown request",
+			STRINGIFY (FCGI_ABORT_REQUEST));
+		return;
+	}
+
+	// TODO: abort the request
+}
+
+static void
+fcgi_muxer_on_params (struct fcgi_muxer *self, const struct fcgi_parser *parser)
+{
+	struct fcgi_request *request = self->requests[parser->request_id];
+	if (!request)
+	{
+		print_debug ("FastCGI: received %s for an unknown request",
+			STRINGIFY (FCGI_PARAMS));
+		return;
+	}
+
+	fcgi_request_push_params (request,
+		parser->content.str, parser->content.len);
+}
+
+static void
+fcgi_muxer_on_stdin (struct fcgi_muxer *self, const struct fcgi_parser *parser)
+{
+	struct fcgi_request *request = self->requests[parser->request_id];
+	if (!request)
+	{
+		print_debug ("FastCGI: received %s for an unknown request",
+			STRINGIFY (FCGI_STDIN));
+		return;
+	}
+
+	fcgi_request_push_stdin (request,
+		parser->content.str, parser->content.len);
+}
+
+static void
 fcgi_muxer_on_message (const struct fcgi_parser *parser, void *user_data)
 {
 	struct fcgi_muxer *self = user_data;
 
-	// TODO
+	if (parser->version != FCGI_VERSION_1)
+	{
+		print_debug ("FastCGI: unsupported version %d", parser->version);
+		// TODO: also return false to stop processing on protocol error?
+		return;
+	}
+
+	static const fcgi_muxer_handler_fn handlers[] =
+	{
+		[FCGI_GET_VALUES]    = fcgi_muxer_on_get_values,
+		[FCGI_BEGIN_REQUEST] = fcgi_muxer_on_begin_request,
+		[FCGI_ABORT_REQUEST] = fcgi_muxer_on_abort_request,
+		[FCGI_PARAMS]        = fcgi_muxer_on_params,
+		[FCGI_STDIN]         = fcgi_muxer_on_stdin,
+	};
+
+	fcgi_muxer_handler_fn handler;
+	if (parser->type >= N_ELEMENTS (handlers)
+	 || !(handler = handlers[parser->type]))
+	{
+		uint8_t content[8] = { parser->type };
+		fcgi_muxer_send (self, FCGI_UNKNOWN_TYPE, parser->request_id,
+			content, sizeof content);
+		return;
+	}
+
+	handler (self, parser);
 }
 
 static void
@@ -649,6 +1010,7 @@ struct server_context
 	struct client *clients;             ///< Clients
 	unsigned n_clients;                 ///< Current number of connections
 
+	struct request_handler *handlers;   ///< Request handlers
 	struct str_map config;              ///< Server configuration
 };
 
@@ -672,19 +1034,58 @@ server_context_free (struct server_context *self)
 
 // --- JSON-RPC ----------------------------------------------------------------
 
-// TODO: this is where we're actually supposed to do JSON-RPC 2.0 processing
+#define JSON_RPC_ERROR_TABLE(XX)                                               \
+	XX (-32700, PARSE_ERROR,      "Parse error")                               \
+	XX (-32600, INVALID_REQUEST,  "Invalid Request")                           \
+	XX (-32601, METHOD_NOT_FOUND, "Method not found")                          \
+	XX (-32602, INVALID_PARAMS,   "Invalid params")                            \
+	XX (-32603, INTERNAL_ERROR,   "Internal error")
+
+enum json_rpc_error
+{
+#define XX(code, name, message) JSON_RPC_ERROR_ ## name,
+	JSON_RPC_ERROR_TABLE (XX)
+#undef XX
+	JSON_RPC_ERROR_COUNT
+};
+
+static json_t *
+json_rpc_error (enum json_rpc_error id, json_t *data)
+{
+#define XX(code, name, message) { code, message },
+	static const struct json_rpc_error
+	{
+		int code;
+		const char *message;
+	}
+	errors[JSON_RPC_ERROR_COUNT] =
+	{
+		JSON_RPC_ERROR_TABLE (XX)
+	};
+#undef XX
+
+	json_t *error = json_object ();
+	json_object_set_new (error, "code",    json_integer (errors[id].code));
+	json_object_set_new (error, "message", json_string  (errors[id].message));
 
-// There's probably no reason to create an object for this.
-//
-// We probably just want a handler function that takes a JSON string, parses it,
-// and returns back another JSON string.
-//
-// Then there should be another function that takes a parsed JSON request and
-// returns back a JSON reply.  This function may get called multiple times if
-// the user sends a batch request.
+	if (data)
+		json_object_set_new (error, "data", data);
 
-// TODO: a function that queues up a ping over IRC: this has to be owned by the
-//   server context as a background job that removes itself upon completion.
+	return error;
+}
+
+static json_t *
+json_rpc_response (json_t *id, json_t *result, json_t *error)
+{
+	json_t *x = json_object ();
+	json_object_set_new (x, "jsonrpc", json_string ("2.0"));
+	json_object_set_new (x, "id", id ? id : json_null ());
+	if (result)  json_object_set_new (x, "result", result);
+	if (error)   json_object_set_new (x, "error",  error);
+	return x;
+}
+
+// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
 
 static bool
 try_advance (const char **p, const char *text)
@@ -728,11 +1129,128 @@ validate_json_rpc_content_type (const char *type)
 	return !*type;
 }
 
+// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
+
+// TODO: a method that queues up a ping over IRC: this has to be owned by the
+//   server context as a background job that removes itself upon completion.
+
+static json_t *
+json_rpc_ping (struct server_context *ctx, json_t *params)
+{
+	(void) ctx;
+	(void) params;
+
+	return json_rpc_response (NULL, json_string ("pong"), NULL);
+}
+
+static json_t *
+process_json_rpc_request (struct server_context *ctx, json_t *request)
+{
+	// TODO: takes a parsed JSON request and returns back a JSON reply.
+	//   This function may get called multiple times for batch requests.
+
+	if (!json_is_object (request))
+		return json_rpc_response (NULL, NULL,
+			json_rpc_error (JSON_RPC_ERROR_INVALID_REQUEST, NULL));
+
+	json_t *v      = json_object_get (request, "jsonrpc");
+	json_t *m      = json_object_get (request, "method");
+	json_t *params = json_object_get (request, "params");
+	json_t *id     = json_object_get (request, "id");
+
+	const char *version;
+	const char *method;
+
+	bool ok = true;
+	ok &= v && (version = json_string_value (v)) && !strcmp (version, "2.0");
+	ok &= m && (method  = json_string_value (m));
+	ok &= !params || json_is_array (params) || json_is_object (params);
+	ok &= !id || json_is_null (id) ||
+		json_is_string (id) || json_is_number (id);
+	if (!ok)
+		return json_rpc_response (id, NULL,
+			json_rpc_error (JSON_RPC_ERROR_INVALID_REQUEST, NULL));
+
+	// TODO: add a more extensible mechanism
+	json_t *response = NULL;
+	if (!strcmp (method, "ping"))
+		response = json_rpc_ping (ctx, params);
+	else
+		return json_rpc_response (id, NULL,
+			json_rpc_error (JSON_RPC_ERROR_METHOD_NOT_FOUND, NULL));
+
+	if (id)
+		return response;
+
+	// Notifications don't get responses
+	// TODO: separate notifications from non-notifications?
+	json_decref (response);
+	return NULL;
+}
+
+static void
+flush_json (json_t *json, struct str *output)
+{
+	char *utf8 = json_dumps (json, JSON_ENCODE_ANY);
+	str_append (output, utf8);
+	free (utf8);
+	json_decref (json);
+}
+
+static void
+process_json_rpc (struct server_context *ctx,
+	const void *data, size_t len, struct str *output)
+{
+
+	json_error_t e;
+	json_t *request;
+	if (!(request = json_loadb (data, len, JSON_DECODE_ANY, &e)))
+	{
+		flush_json (json_rpc_response (NULL, NULL,
+			json_rpc_error (JSON_RPC_ERROR_PARSE_ERROR, NULL)),
+			output);
+		return;
+	}
+
+	if (json_is_array (request))
+	{
+		if (!json_array_size (request))
+		{
+			flush_json (json_rpc_response (NULL, NULL,
+				json_rpc_error (JSON_RPC_ERROR_INVALID_REQUEST, NULL)),
+				output);
+			return;
+		}
+
+		json_t *response = json_array ();
+		json_t *iter;
+		size_t i;
+
+		json_array_foreach (request, i, iter)
+		{
+			json_t *result = process_json_rpc_request (ctx, iter);
+			if (result)
+				json_array_append_new (response, result);
+		}
+
+		if (json_array_size (response))
+			flush_json (response, output);
+		else
+			json_decref (response);
+	}
+	else
+	{
+		json_t *result = process_json_rpc_request (ctx, request);
+		if (result)
+			flush_json (result, output);
+	}
+}
+
 // --- Requests ----------------------------------------------------------------
 
 struct request
 {
-	// TODO *ctx
+	struct server_context *ctx;         ///< Server context
 
 	void *user_data;                    ///< User data argument for callbacks
 
@@ -749,6 +1267,8 @@ struct request
 
 struct request_handler
 {
+	LIST_HEADER (struct request_handler)
+
 	/// Install ourselves as the handler for the request if applicable
 	bool (*try_handle) (struct request *request, struct str_map *headers);
 
@@ -785,11 +1305,17 @@ request_finish (struct request *self)
 static bool
 request_start (struct request *self, struct str_map *headers)
 {
-	bool handled = false;
-	// TODO: try request handlers registered in self->ctx
-	if (handled)
-		// TODO: can also be false
-		return true;
+	LIST_FOR_EACH (struct request_handler, handler, self->ctx->handlers)
+		if (handler->try_handle (self, headers))
+		{
+			// XXX: maybe we should isolate the handlers a bit more
+			self->handler = handler;
+
+			// TODO: we should also allow the "try_handle" function to
+			//   return that it has already finished processing the request
+			//   and we should abort it by returning false here.
+			return true;
+		}
 
 	// Unable to serve the request
 	struct str response;
@@ -819,11 +1345,14 @@ request_handler_json_rpc_try_handle
 	const char *content_type = str_map_find (headers, "CONTENT_TYPE");
 	const char *method = str_map_find (headers, "REQUEST_METHOD");
 
-	if (strcmp (method, "POST")
-	 || !validate_json_rpc_content_type (content_type))
+	if (!method || strcmp (method, "POST")
+	 || !content_type || !validate_json_rpc_content_type (content_type))
 		return false;
 
-	// TODO: install the handler, perhaps construct an object
+	struct str *buf = xcalloc (1, sizeof *buf);
+	str_init (buf);
+
+	request->handler_data = buf;
 	return true;
 }
 
@@ -831,15 +1360,28 @@ static bool
 request_handler_json_rpc_push
 	(struct request *request, const void *data, size_t len)
 {
-	// TODO: append to a buffer
-	// TODO: len == 0: process the request
+	struct str *buf = request->handler_data;
+	if (len)
+		str_append_data (buf, data, len);
+	else
+	{
+		struct str response;
+		str_init (&response);
+		process_json_rpc (request->ctx, buf->str, buf->len, &response);
+		request->write_cb (request->user_data, response.str, response.len);
+		str_free (&response);
+	}
 	return true;
 }
 
 static void
 request_handler_json_rpc_destroy (struct request *request)
 {
-	// TODO
+	struct str *buf = request->handler_data;
+	str_free (buf);
+	free (buf);
+
+	request->handler_data = NULL;
 }
 
 struct request_handler g_request_handler_json_rpc =
@@ -849,6 +1391,8 @@ struct request_handler g_request_handler_json_rpc =
 	.destroy_cb = request_handler_json_rpc_destroy,
 };
 
+// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
+
 // TODO: another request handler to respond to all GETs with a message
 
 // --- Client communication handlers -------------------------------------------
@@ -927,17 +1471,86 @@ client_remove (struct client *client)
 
 struct client_fcgi
 {
-	struct fcgi_parser parser;          ///< FastCGI stream parser
+	struct fcgi_muxer muxer;            ///< FastCGI de/multiplexer
+};
+
+struct client_fcgi_request
+{
+	struct fcgi_request *fcgi_request;  ///< FastCGI request
+	struct request request;             ///< Request
 };
 
 static void
+client_fcgi_request_write (void *user_data, const void *data, size_t len)
+{
+	struct client_fcgi_request *request = user_data;
+	fcgi_request_write (request->fcgi_request, data, len);
+}
+
+static void
+client_fcgi_request_close (void *user_data)
+{
+	struct client_fcgi_request *request = user_data;
+	// TODO: tell the fcgi_request to what?
+}
+
+static void *
+client_fcgi_request_start (void *user_data, struct fcgi_request *fcgi_request)
+{
+	struct client *client = user_data;
+
+	struct client_fcgi_request *request = xmalloc (sizeof *request);
+	request->fcgi_request = fcgi_request;
+	request_init (&request->request);
+	request->request.ctx = client->ctx;
+	request->request.write_cb = client_fcgi_request_write;
+	request->request.close_cb = client_fcgi_request_close;
+	request->request.user_data = request;
+	return request;
+}
+
+static void
+client_fcgi_request_push (void *handler_data, const void *data, size_t len)
+{
+	struct client_fcgi_request *request = handler_data;
+	request_push (&request->request, data, len);
+}
+
+static void
+client_fcgi_request_destroy (void *handler_data)
+{
+	struct client_fcgi_request *request = handler_data;
+	request_free (&request->request);
+	free (handler_data);
+}
+
+static void
+client_fcgi_write (void *user_data, const void *data, size_t len)
+{
+	struct client *client = user_data;
+	client_write (client, data, len);
+}
+
+static void
+client_fcgi_close (void *user_data)
+{
+	struct client *client = user_data;
+	client_remove (client);
+}
+
+static void
 client_fcgi_init (struct client *client)
 {
 	struct client_fcgi *self = xcalloc (1, sizeof *self);
 	client->impl_data = self;
 
-	fcgi_parser_init (&self->parser);
-	// TODO: configure the parser
+	fcgi_muxer_init (&self->muxer);
+	self->muxer.write_cb           = client_fcgi_write;
+	self->muxer.close_cb           = client_fcgi_close;
+	self->muxer.request_start_cb   = client_fcgi_request_start;
+	self->muxer.request_push_cb    = client_fcgi_request_push;
+	self->muxer.request_destroy_cb = client_fcgi_request_destroy;
+	self->muxer.user_data          = client;
 }
 
 static void
@@ -946,7 +1559,7 @@ client_fcgi_destroy (struct client *client)
 	struct client_fcgi *self = client->impl_data;
 	client->impl_data = NULL;
 
-	fcgi_parser_free (&self->parser);
+	fcgi_muxer_free (&self->muxer);
 	free (self);
 }
 
@@ -954,7 +1567,7 @@ static bool
 client_fcgi_push (struct client *client, const void *data, size_t len)
 {
 	struct client_fcgi *self = client->impl_data;
-	fcgi_parser_push (&self->parser, data, len);
+	fcgi_muxer_push (&self->muxer, data, len);
 	return true;
 }
 
@@ -1015,6 +1628,7 @@ client_scgi_init (struct client *client)
 	client->impl_data = self;
 
 	request_init (&self->request);
+	self->request.ctx            = client->ctx;
 	self->request.write_cb       = client_scgi_write;
 	self->request.close_cb       = client_scgi_close;
 	self->request.user_data      = client;
@@ -1426,6 +2040,8 @@ main (int argc, char *argv[])
 
 	(void) signal (SIGPIPE, SIG_IGN);
 
+	LIST_PREPEND (ctx.handlers, &g_request_handler_json_rpc);
+
 	if (!parse_config (&ctx, &e)
 	 || !setup_listen_fds (&ctx, &e))
 	{