Merge in a JSON-RPC 2.0 test server

6 files changed, 2955 insertions, 1 deletions

diff --git a/CMakeLists.txt b/CMakeLists.txt
index 58767c6..5b1bd3d 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -70,6 +70,16 @@ include_directories (${PROJECT_BINARY_DIR})
 add_executable (${PROJECT_NAME} ${PROJECT_NAME}.c http-parser/http_parser.c)
 target_link_libraries (${PROJECT_NAME} ${project_libraries})
 
+# Development tools
+find_package (LibMagic)
+if (LIBMAGIC_FOUND)
+	include_directories (${LIBMAGIC_INCLUDE_DIRS})
+	add_executable (json-rpc-test-server
+		json-rpc-test-server.c http-parser/http_parser.c)
+	target_link_libraries (json-rpc-test-server
+		${project_libraries} ${LIBMAGIC_LIBRARIES})
+endif ()
+
 # The files to be installed
 include (GNUInstallDirs)
 install (TARGETS ${PROJECT_NAME} DESTINATION ${CMAKE_INSTALL_BINDIR})
diff --git a/LICENSE b/LICENSE
index 438cd83..a069461 100644
--- a/LICENSE
+++ b/LICENSE
@@ -1,4 +1,4 @@
-Copyright (c) 2014 - 2016, Přemysl Janouch <p@janouch.name>
+Copyright (c) 2014 - 2018, Přemysl Janouch <p@janouch.name>
 
 Permission to use, copy, modify, and/or distribute this software for any
 purpose with or without fee is hereby granted.
diff --git a/README.adoc b/README.adoc
index 3112f9f..9c4fec4 100644
--- a/README.adoc
+++ b/README.adoc
@@ -67,6 +67,12 @@ Note that for versions of CMake before 2.8.9, you need to prefix `cpack` with
 
 Run the program with `--help` to obtain usage information.
 
+Test server
+-----------
+If you install development packages for libmagic, an included test server will
+be built but not installed which provides a trivial JSON-RPC 2.0 service with
+FastCGI, SCGI, and WebSocket interfaces.  It responds to the `ping` method.
+
 Contributing and Support
 ------------------------
 Use https://git.janouch.name/p/json-rpc-shell to report bugs, request features,
diff --git a/cmake/FindLibMagic.cmake b/cmake/FindLibMagic.cmake
new file mode 100644
index 0000000..9bed3b3
--- /dev/null
+++ b/cmake/FindLibMagic.cmake
@@ -0,0 +1,10 @@
+# Public Domain
+
+find_library (LIBMAGIC_LIBRARIES magic)
+find_path (LIBMAGIC_INCLUDE_DIRS magic.h)
+
+include (FindPackageHandleStandardArgs)
+find_package_handle_standard_args (LibMagic DEFAULT_MSG
+	LIBMAGIC_LIBRARIES LIBMAGIC_INCLUDE_DIRS)
+
+mark_as_advanced (LIBMAGIC_LIBRARIES LIBMAGIC_INCLUDE_DIRS)
diff --git a/json-rpc-test-server.c b/json-rpc-test-server.c
new file mode 100644
index 0000000..ea38b7b
--- /dev/null
+++ b/json-rpc-test-server.c
@@ -0,0 +1,2928 @@
+/*
+ * json-rpc-test-server.c: JSON-RPC 2.0 demo server
+ *
+ * Copyright (c) 2015 - 2018, Přemysl Janouch <p@janouch.name>
+ *
+ * Permission to use, copy, modify, and/or distribute this software for any
+ * purpose with or without fee is hereby granted.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY
+ * SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION
+ * OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN
+ * CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ *
+ */
+
+#define print_fatal_data    ((void *) LOG_ERR)
+#define print_error_data    ((void *) LOG_ERR)
+#define print_warning_data  ((void *) LOG_WARNING)
+#define print_status_data   ((void *) LOG_INFO)
+#define print_debug_data    ((void *) LOG_DEBUG)
+
+#define LIBERTY_WANT_SSL
+#define LIBERTY_WANT_PROTO_HTTP
+#define LIBERTY_WANT_PROTO_WS
+#define LIBERTY_WANT_PROTO_SCGI
+#define LIBERTY_WANT_PROTO_FASTCGI
+
+#include "config.h"
+#undef PROGRAM_NAME
+#define PROGRAM_NAME "json-rpc-test-server"
+
+#include "liberty/liberty.c"
+
+#include <langinfo.h>
+#include <locale.h>
+#include <signal.h>
+#include <strings.h>
+
+#include <ev.h>
+#include <jansson.h>
+#include <magic.h>
+
+#include "http-parser/http_parser.h"
+
+enum { PIPE_READ, PIPE_WRITE };
+
+#define FIND_CONTAINER(name, pointer, type, member) \
+	type *name = CONTAINER_OF (pointer, type, member)
+
+// --- Utilities ---------------------------------------------------------------
+
+static bool
+flush_queue (struct write_queue *queue, int fd)
+{
+	struct iovec vec[queue->len], *vec_iter = vec;
+	LIST_FOR_EACH (struct write_req, iter, queue->head)
+		*vec_iter++ = iter->data;
+
+	ssize_t written;
+again:
+	if ((written = writev (fd, vec, N_ELEMENTS (vec))) >= 0)
+	{
+		write_queue_processed (queue, written);
+		return true;
+	}
+	if (errno == EINTR)
+		goto again;
+	if (errno == EAGAIN)
+		return true;
+
+	return false;
+}
+
+// --- Logging -----------------------------------------------------------------
+
+static void
+log_message_syslog (void *user_data, const char *quote, const char *fmt,
+	va_list ap)
+{
+	int prio = (int) (intptr_t) user_data;
+
+	va_list va;
+	va_copy (va, ap);
+	int size = vsnprintf (NULL, 0, fmt, va);
+	va_end (va);
+	if (size < 0)
+		return;
+
+	char buf[size + 1];
+	if (vsnprintf (buf, sizeof buf, fmt, ap) >= 0)
+		syslog (prio, "%s%s", quote, buf);
+}
+
+// --- FastCGI -----------------------------------------------------------------
+/// @defgroup FastCGI
+/// @{
+
+enum fcgi_request_state
+{
+	FCGI_REQUEST_PARAMS,                ///< Reading headers
+	FCGI_REQUEST_STDIN                  ///< Reading input
+};
+
+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
+
+	struct str output_buffer;           ///< Output buffer
+
+	void *handler_data;                 ///< Handler data
+};
+
+/// Handles a single FastCGI connection, de/multiplexing requests and responses
+struct fcgi_muxer
+{
+	struct fcgi_parser parser;          ///< FastCGI message parser
+	uint32_t active_requests;           ///< The number of active requests
+	bool in_shutdown;                   ///< Rejecting new requests
+
+	// Virtual method callbacks:
+
+	/// Write data to the underlying transport
+	void (*write_cb) (struct fcgi_muxer *, const void *data, size_t len);
+
+	/// Close the underlying transport.  You are allowed to destroy the muxer
+	/// directly from within the callback.
+	void (*close_cb) (struct fcgi_muxer *);
+
+	/// Start processing a request.  Return false if no further action is
+	/// to be done and the request should be finished.
+	bool (*request_start_cb) (struct fcgi_request *);
+
+	/// Handle incoming data.  "len == 0" means EOF.  Returns false if
+	/// the underlying transport should be closed, this being the last request.
+	bool (*request_push_cb)
+		(struct fcgi_request *, const void *data, size_t len);
+
+	/// Destroy the handler's data stored in the request object
+	void (*request_finalize_cb) (struct fcgi_request *);
+
+	/// Requests assigned to request IDs (may not be FCGI_NULL_REQUEST_ID)
+	struct fcgi_request *requests[1 << 8];
+};
+
+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_make ();
+	static char zeroes[8];
+	size_t padding = -len & 7;
+
+	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, padding); // padding length
+	str_pack_u8  (&message, 0);       // reserved
+
+	str_append_data (&message, data, len);
+	str_append_data (&message, zeroes, padding);
+
+	// XXX: we should probably have another write_cb that assumes ownership
+	self->write_cb (self, 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 struct fcgi_request *
+fcgi_request_new (void)
+{
+	struct fcgi_request *self = xcalloc (1, sizeof *self);
+
+	self->headers = str_map_make (free);
+
+	self->hdr_parser = fcgi_nv_parser_make ();
+	self->hdr_parser.output = &self->headers;
+
+	self->output_buffer = str_make ();
+	return self;
+}
+
+static void
+fcgi_request_destroy (struct fcgi_request *self)
+{
+	// TODO: consider the case where it hasn't been started yet
+	self->muxer->request_finalize_cb (self);
+
+	str_map_free (&self->headers);
+	fcgi_nv_parser_free (&self->hdr_parser);
+	free (self);
+}
+
+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);
+	}
+}
+
+/// Mark the request as done.  Returns false if the underlying transport
+/// should be closed, this being the last request.
+static bool
+fcgi_request_finish (struct fcgi_request *self)
+{
+	fcgi_request_flush (self);
+	fcgi_muxer_send (self->muxer, FCGI_STDOUT, self->request_id, NULL, 0);
+
+	fcgi_muxer_send_end_request (self->muxer, self->request_id,
+		0 /* TODO app_status, although ignored */,
+		FCGI_REQUEST_COMPLETE /* TODO protocol_status, may be different */);
+
+	bool should_close = !(self->flags & FCGI_KEEP_CONN);
+
+	self->muxer->active_requests--;
+	self->muxer->requests[self->request_id] = NULL;
+	fcgi_request_destroy (self);
+
+	return !should_close;
+}
+
+static bool
+fcgi_request_push_params
+	(struct fcgi_request *self, const void *data, size_t len)
+{
+	if (self->state != FCGI_REQUEST_PARAMS)
+	{
+		print_debug ("FastCGI: expected %s, got %s",
+			STRINGIFY (FCGI_STDIN), STRINGIFY (FCGI_PARAMS));
+		return false;
+	}
+
+	if (len)
+		fcgi_nv_parser_push (&self->hdr_parser, data, len);
+	else
+	{
+		if (self->hdr_parser.state != FCGI_NV_PARSER_NAME_LEN)
+			print_debug ("FastCGI: request headers seem to be cut off");
+
+		self->state = FCGI_REQUEST_STDIN;
+		if (!self->muxer->request_start_cb (self))
+			return fcgi_request_finish (self);
+	}
+	return true;
+}
+
+static bool
+fcgi_request_push_stdin
+	(struct fcgi_request *self, const void *data, size_t len)
+{
+	if (self->state != FCGI_REQUEST_STDIN)
+	{
+		print_debug ("FastCGI: expected %s, got %s",
+			STRINGIFY (FCGI_PARAMS), STRINGIFY (FCGI_STDIN));
+		return false;
+	}
+
+	return self->muxer->request_push_cb (self, data, len);
+}
+
+// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
+
+typedef bool (*fcgi_muxer_handler_fn)
+	(struct fcgi_muxer *, const struct fcgi_parser *);
+
+static bool
+fcgi_muxer_on_get_values
+	(struct fcgi_muxer *self, const struct fcgi_parser *parser)
+{
+	if (parser->request_id != FCGI_NULL_REQUEST_ID)
+	{
+		print_debug ("FastCGI: invalid %s message",
+			STRINGIFY (FCGI_GET_VALUES));
+		return false;
+	}
+
+	struct str_map values   = str_map_make (free);
+	struct str_map response = str_map_make (free);
+
+	struct fcgi_nv_parser nv_parser = fcgi_nv_parser_make ();
+	nv_parser.output = &values;
+
+	fcgi_nv_parser_push (&nv_parser, parser->content.str, parser->content.len);
+	const char *key = NULL;
+
+	// No real-world servers seem to actually use multiplexing
+	// or even issue this request, but we will implement it anyway
+	if (str_map_find (&values, (key = FCGI_MPXS_CONNS)))
+		str_map_set (&response, key, xstrdup ("1"));
+
+	// It's not clear whether FCGI_MAX_REQS means concurrently over all
+	// connections or over just a single connection (multiplexed), though
+	// supposedly it's actually per /web server/.  Supply the strictest limit.
+	if (str_map_find (&values, (key = FCGI_MAX_REQS)))
+		str_map_set (&response, key,
+			xstrdup_printf ("%zu", N_ELEMENTS (self->requests) - 1));
+
+	// FCGI_MAX_CONNS would be basically infinity.  We don't limit connections.
+
+	struct str content = str_make ();
+	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);
+	return true;
+}
+
+static bool
+fcgi_muxer_on_begin_request
+	(struct fcgi_muxer *self, const struct fcgi_parser *parser)
+{
+	struct msg_unpacker unpacker =
+		msg_unpacker_make (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: invalid %s message",
+			STRINGIFY (FCGI_BEGIN_REQUEST));
+		return false;
+	}
+
+	struct fcgi_request *request = self->requests[parser->request_id];
+	if (parser->request_id == FCGI_NULL_REQUEST_ID || request)
+	{
+		print_debug ("FastCGI: unusable request ID in %s message",
+			STRINGIFY (FCGI_BEGIN_REQUEST));
+		return false;
+	}
+
+	// We can only act as a responder, reject everything else up front
+	if (role != FCGI_RESPONDER)
+	{
+		fcgi_muxer_send_end_request (self,
+			parser->request_id, 0, FCGI_UNKNOWN_ROLE);
+		return true;
+	}
+
+	if (parser->request_id >= N_ELEMENTS (self->requests)
+	 || self->in_shutdown)
+	{
+		fcgi_muxer_send_end_request (self,
+			parser->request_id, 0, FCGI_OVERLOADED);
+		return true;
+	}
+
+	request = fcgi_request_new ();
+	request->muxer = self;
+	request->request_id = parser->request_id;
+	request->flags = flags;
+
+	self->requests[parser->request_id] = request;
+	self->active_requests++;
+	return true;
+}
+
+static bool
+fcgi_muxer_on_abort_request
+	(struct fcgi_muxer *self, const struct fcgi_parser *parser)
+{
+	struct fcgi_request *request = self->requests[parser->request_id];
+	if (parser->request_id == FCGI_NULL_REQUEST_ID || !request)
+	{
+		print_debug ("FastCGI: received %s for an unknown request",
+			STRINGIFY (FCGI_ABORT_REQUEST));
+		return true;  // We might have just rejected it
+	}
+
+	return fcgi_request_finish (request);
+}
+
+static bool
+fcgi_muxer_on_params (struct fcgi_muxer *self, const struct fcgi_parser *parser)
+{
+	struct fcgi_request *request = self->requests[parser->request_id];
+	if (parser->request_id == FCGI_NULL_REQUEST_ID || !request)
+	{
+		print_debug ("FastCGI: received %s for an unknown request",
+			STRINGIFY (FCGI_PARAMS));
+		return true;  // We might have just rejected it
+	}
+
+	// This may immediately finish and delete the request, but that's fine
+	return fcgi_request_push_params (request,
+		parser->content.str, parser->content.len);
+}
+
+static bool
+fcgi_muxer_on_stdin (struct fcgi_muxer *self, const struct fcgi_parser *parser)
+{
+	struct fcgi_request *request = self->requests[parser->request_id];
+	if (parser->request_id == FCGI_NULL_REQUEST_ID || !request)
+	{
+		print_debug ("FastCGI: received %s for an unknown request",
+			STRINGIFY (FCGI_STDIN));
+		return true;  // We might have just rejected it
+	}
+
+	// At the end of the stream, a zero-length record is received
+	return fcgi_request_push_stdin (request,
+		parser->content.str, parser->content.len);
+}
+
+static bool
+fcgi_muxer_on_message (const struct fcgi_parser *parser, void *user_data)
+{
+	struct fcgi_muxer *self = user_data;
+
+	if (parser->version != FCGI_VERSION_1)
+	{
+		print_debug ("FastCGI: unsupported version %d", parser->version);
+		return false;
+	}
+
+	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]))
+	{
+		// Responding in this way even to application records, unspecified
+		uint8_t content[8] = { parser->type };
+		fcgi_muxer_send (self, FCGI_UNKNOWN_TYPE, parser->request_id,
+			content, sizeof content);
+		return true;
+	}
+
+	return handler (self, parser);
+}
+
+static void
+fcgi_muxer_init (struct fcgi_muxer *self)
+{
+	self->parser = fcgi_parser_make ();
+	self->parser.on_message = fcgi_muxer_on_message;
+	self->parser.user_data = self;
+}
+
+static void
+fcgi_muxer_free (struct fcgi_muxer *self)
+{
+	for (size_t i = 0; i < N_ELEMENTS (self->requests); i++)
+	{
+		if (!self->active_requests)
+			break;
+		if (self->requests[i])
+		{
+			fcgi_request_destroy (self->requests[i]);
+			self->active_requests--;
+		}
+	}
+
+	fcgi_parser_free (&self->parser);
+}
+
+static bool
+fcgi_muxer_push (struct fcgi_muxer *self, const void *data, size_t len)
+{
+	return fcgi_parser_push (&self->parser, data, len);
+}
+
+/// @}
+// --- WebSockets --------------------------------------------------------------
+/// @defgroup WebSockets
+/// @{
+
+// WebSockets aren't CGI-compatible, therefore we must handle the initial HTTP
+// handshake ourselves.  Luckily it's not too much of a bother with http-parser.
+// Typically there will be a normal HTTP server in front of us, proxying the
+// requests based on the URI.
+
+enum ws_handler_state
+{
+	WS_HANDLER_CONNECTING,              ///< Parsing HTTP
+	WS_HANDLER_OPEN,                    ///< Parsing WebSockets frames
+	WS_HANDLER_CLOSING,                 ///< Partial closure by us
+	WS_HANDLER_FLUSHING,                ///< Just waiting for client EOF
+	WS_HANDLER_CLOSED                   ///< Dead, both sides closed
+};
+
+struct ws_handler
+{
+	enum ws_handler_state state;        ///< State
+
+	// HTTP handshake:
+
+	http_parser hp;                     ///< HTTP parser
+	bool have_header_value;             ///< Parsing header value or field?
+	struct str field;                   ///< Field part buffer
+	struct str value;                   ///< Value part buffer
+	struct str_map headers;             ///< HTTP Headers
+	struct str url;                     ///< Request URL
+	ev_timer handshake_timeout_watcher; ///< Handshake timeout watcher
+
+	// WebSocket frame protocol:
+
+	struct ws_parser parser;            ///< Protocol frame parser
+	bool expecting_continuation;        ///< For non-control traffic
+
+	enum ws_opcode message_opcode;      ///< Opcode for the current message
+	struct str message_data;            ///< Concatenated message data
+
+	ev_timer ping_timer;                ///< Ping timer
+	bool received_pong;                 ///< Received PONG since the last PING
+
+	ev_timer close_timeout_watcher;     ///< Close timeout watcher
+
+	// Configuration:
+
+	unsigned handshake_timeout;         ///< How long to wait for the handshake
+	unsigned close_timeout;             ///< How long to wait for TCP close
+	unsigned ping_interval;             ///< Ping interval in seconds
+	uint64_t max_payload_len;           ///< Maximum length of any message
+
+	// Event callbacks:
+
+	// TODO: void (*on_handshake) (protocols) that will allow the user
+	//   to choose any sub-protocol, if the client has provided any.
+	//   This may render "on_connected" unnecessary.
+	//   Should also enable failing the handshake.
+
+	/// Called after successfuly connecting (handshake complete)
+	bool (*on_connected) (struct ws_handler *);
+
+	/// Called upon reception of a single full message
+	bool (*on_message) (struct ws_handler *,
+		enum ws_opcode type, const void *data, size_t len);
+
+	/// The connection is about to close.  @a close_code may, or may not, be one
+	/// of enum ws_status.  The @a reason is never NULL.
+	void (*on_close) (struct ws_handler *, int close_code, const char *reason);
+
+	// Virtual method callbacks:
+
+	/// Write a chunk of data to the stream
+	void (*write_cb) (struct ws_handler *, const void *data, size_t len);
+
+	/// Close the connection.  If @a half_close is false, you are allowed to
+	/// destroy the handler directly from within the callback.
+	void (*close_cb) (struct ws_handler *, bool half_close);
+};
+
+static void
+ws_handler_send_control (struct ws_handler *self,
+	enum ws_opcode opcode, const void *data, size_t len)
+{
+	if (len > WS_MAX_CONTROL_PAYLOAD_LEN)
+	{
+		print_debug ("truncating output control frame payload"
+			" from %zu to %zu bytes", len, (size_t) WS_MAX_CONTROL_PAYLOAD_LEN);
+		len = WS_MAX_CONTROL_PAYLOAD_LEN;
+	}
+
+	uint8_t header[2] = { 0x80 | (opcode & 0x0F), len };
+	self->write_cb (self, header, sizeof header);
+	self->write_cb (self, data, len);
+}
+
+static void
+ws_handler_close (struct ws_handler *self,
+	enum ws_status close_code, const char *reason, size_t len)
+{
+	hard_assert (self->state == WS_HANDLER_OPEN);
+
+	struct str payload = str_make ();
+	str_pack_u16 (&payload, close_code);
+	// XXX: maybe accept a null-terminated string on input? Has to be UTF-8 a/w
+	str_append_data (&payload, reason, len);
+	ws_handler_send_control (self, WS_OPCODE_CLOSE, payload.str, payload.len);
+	self->close_cb (self, true /* half_close */);
+
+	self->state = WS_HANDLER_CLOSING;
+	str_free (&payload);
+}
+
+static bool
+ws_handler_fail_connection (struct ws_handler *self, enum ws_status close_code)
+{
+	hard_assert (self->state == WS_HANDLER_OPEN
+		|| self->state == WS_HANDLER_CLOSING);
+
+	if (self->state == WS_HANDLER_OPEN)
+		ws_handler_close (self, close_code, NULL, 0);
+
+	self->state = WS_HANDLER_FLUSHING;
+	if (self->on_close)
+		self->on_close (self, WS_STATUS_ABNORMAL_CLOSURE, "");
+
+	ev_timer_stop (EV_DEFAULT_ &self->ping_timer);
+	ev_timer_set (&self->close_timeout_watcher, self->close_timeout, 0.);
+	ev_timer_start (EV_DEFAULT_ &self->close_timeout_watcher);
+	return false;
+}
+
+// TODO: add support for fragmented responses
+static void
+ws_handler_send_frame (struct ws_handler *self,
+	enum ws_opcode opcode, const void *data, size_t len)
+{
+	if (!soft_assert (self->state == WS_HANDLER_OPEN))
+		return;
+
+	struct str header = str_make ();
+	str_pack_u8 (&header, 0x80 | (opcode & 0x0F));
+
+	if (len > UINT16_MAX)
+	{
+		str_pack_u8 (&header, 127);
+		str_pack_u64 (&header, len);
+	}
+	else if (len > 125)
+	{
+		str_pack_u8 (&header, 126);
+		str_pack_u16 (&header, len);
+	}
+	else
+		str_pack_u8 (&header, len);
+
+	self->write_cb (self, header.str, header.len);
+	self->write_cb (self, data, len);
+	str_free (&header);
+}
+
+static bool
+ws_handler_on_frame_header (void *user_data, const struct ws_parser *parser)
+{
+	struct ws_handler *self = user_data;
+
+	// Note that we aren't expected to send any close frame before closing the
+	// connection when the frame is unmasked
+
+	if (parser->reserved_1 || parser->reserved_2 || parser->reserved_3
+	 || !parser->is_masked  // client -> server payload must be masked
+	 || (ws_is_control_frame (parser->opcode) &&
+		(!parser->is_fin || parser->payload_len > WS_MAX_CONTROL_PAYLOAD_LEN))
+	 || (!ws_is_control_frame (parser->opcode) &&
+		(self->expecting_continuation && parser->opcode != WS_OPCODE_CONT))
+	 || parser->payload_len >= 0x8000000000000000ULL)
+		return ws_handler_fail_connection (self, WS_STATUS_PROTOCOL_ERROR);
+
+	if (parser->payload_len > self->max_payload_len
+	 || (self->expecting_continuation &&
+		self->message_data.len + parser->payload_len > self->max_payload_len))
+		return ws_handler_fail_connection (self, WS_STATUS_MESSAGE_TOO_BIG);
+	return true;
+}
+
+static bool
+ws_handler_on_control_close
+	(struct ws_handler *self, const struct ws_parser *parser)
+{
+	hard_assert (self->state == WS_HANDLER_OPEN
+		|| self->state == WS_HANDLER_CLOSING);
+	struct msg_unpacker unpacker =
+		msg_unpacker_make (parser->input.str, parser->payload_len);
+
+	char *reason = NULL;
+	uint16_t close_code = WS_STATUS_NO_STATUS_RECEIVED;
+	if (parser->payload_len >= 2)
+	{
+		(void) msg_unpacker_u16 (&unpacker, &close_code);
+		reason = xstrndup (parser->input.str + 2, parser->payload_len - 2);
+	}
+	else
+		reason = xstrdup ("");
+
+	if (close_code < 1000 || close_code > 4999)
+		// XXX: invalid close code: maybe we should fail the connection instead
+		close_code = WS_STATUS_PROTOCOL_ERROR;
+
+	if (self->state == WS_HANDLER_OPEN)
+	{
+		// Close initiated by the client
+		// FIXME: not sending the potentially different close_code
+		ws_handler_send_control (self, WS_OPCODE_CLOSE,
+			parser->input.str, parser->payload_len);
+
+		self->state = WS_HANDLER_FLUSHING;
+		if (self->on_close)
+			self->on_close (self, close_code, reason);
+	}
+	else
+		self->state = WS_HANDLER_FLUSHING;
+
+	free (reason);
+
+	ev_timer_stop (EV_DEFAULT_ &self->ping_timer);
+	ev_timer_set (&self->close_timeout_watcher, self->close_timeout, 0.);
+	ev_timer_start (EV_DEFAULT_ &self->close_timeout_watcher);
+	return true;
+}
+
+static bool
+ws_handler_on_control_frame
+	(struct ws_handler *self, const struct ws_parser *parser)
+{
+	switch (parser->opcode)
+	{
+	case WS_OPCODE_CLOSE:
+		return ws_handler_on_control_close (self, parser);
+	case WS_OPCODE_PING:
+		ws_handler_send_control (self, WS_OPCODE_PONG,
+			parser->input.str, parser->payload_len);
+		break;
+	case WS_OPCODE_PONG:
+		// TODO: check the payload
+		self->received_pong = true;
+		break;
+	default:
+		// Unknown control frame
+		return ws_handler_fail_connection (self, WS_STATUS_PROTOCOL_ERROR);
+	}
+	return true;
+}
+
+static bool
+ws_handler_on_frame (void *user_data, const struct ws_parser *parser)
+{
+	struct ws_handler *self = user_data;
+	if (ws_is_control_frame (parser->opcode))
+		return ws_handler_on_control_frame (self, parser);
+	if (!self->expecting_continuation)
+		self->message_opcode = parser->opcode;
+
+	str_append_data (&self->message_data,
+		parser->input.str, parser->payload_len);
+	if ((self->expecting_continuation = !parser->is_fin))
+		return true;
+
+	if (self->message_opcode == WS_OPCODE_TEXT
+	 && !utf8_validate (self->message_data.str, self->message_data.len))
+	{
+		return ws_handler_fail_connection
+			(self, WS_STATUS_INVALID_PAYLOAD_DATA);
+	}
+
+	bool result = true;
+	if (self->on_message)
+		result = self->on_message (self, self->message_opcode,
+			self->message_data.str, self->message_data.len);
+	str_reset (&self->message_data);
+	// TODO: if (!result), either replace this with a state check,
+	//   or make sure to change the state
+	return result;
+}
+
+static void
+ws_handler_on_ping_timer (EV_P_ ev_timer *watcher, int revents)
+{
+	(void) loop;
+	(void) revents;
+
+	struct ws_handler *self = watcher->data;
+	if (!self->received_pong)
+		ws_handler_fail_connection (self, 4000);
+	else
+	{
+		// TODO: be an annoying server and send a nonce in the data
+		ws_handler_send_control (self, WS_OPCODE_PING, NULL, 0);
+		ev_timer_again (EV_A_ watcher);
+	}
+}
+
+static void
+ws_handler_on_close_timeout (EV_P_ ev_timer *watcher, int revents)
+{
+	(void) loop;
+	(void) revents;
+	struct ws_handler *self = watcher->data;
+
+	hard_assert (self->state == WS_HANDLER_OPEN
+		|| self->state == WS_HANDLER_CLOSING);
+
+	if (self->state == WS_HANDLER_CLOSING
+	 && self->on_close)
+		self->on_close (self, WS_STATUS_ABNORMAL_CLOSURE, "close timeout");
+
+	self->state = WS_HANDLER_CLOSED;
+	self->close_cb (self, false /* half_close */);
+}
+
+static void
+ws_handler_on_handshake_timeout (EV_P_ ev_timer *watcher, int revents)
+{
+	(void) loop;
+	(void) revents;
+	struct ws_handler *self = watcher->data;
+
+	// XXX: this is a no-op, since this currently doesn't even call shutdown
+	//   immediately but postpones it until later
+	self->close_cb (self, true /* half_close */);
+	self->state = WS_HANDLER_FLUSHING;
+
+	if (self->on_close)
+		self->on_close (self, WS_STATUS_ABNORMAL_CLOSURE, "handshake timeout");
+
+	self->state = WS_HANDLER_CLOSED;
+	self->close_cb (self, false /* half_close */);
+}
+
+static void
+ws_handler_init (struct ws_handler *self)
+{
+	memset (self, 0, sizeof *self);
+
+	self->state = WS_HANDLER_CONNECTING;
+
+	http_parser_init (&self->hp, HTTP_REQUEST);
+	self->hp.data = self;
+	self->field = str_make ();
+	self->value = str_make ();
+	self->headers = str_map_make (free);
+	self->headers.key_xfrm = tolower_ascii_strxfrm;
+	self->url = str_make ();
+	ev_timer_init (&self->handshake_timeout_watcher,
+		ws_handler_on_handshake_timeout, 0., 0.);
+	self->handshake_timeout_watcher.data = self;
+
+	self->parser = ws_parser_make ();
+	self->parser.on_frame_header = ws_handler_on_frame_header;
+	self->parser.on_frame = ws_handler_on_frame;
+	self->parser.user_data = self;
+	self->message_data = str_make ();
+
+	ev_timer_init (&self->ping_timer,
+		ws_handler_on_ping_timer, 0., 0.);
+	self->ping_timer.data = self;
+	ev_timer_init (&self->close_timeout_watcher,
+		ws_handler_on_close_timeout, 0., 0.);
+	self->ping_timer.data = self;
+	// So that the first ping timer doesn't timeout the connection
+	self->received_pong = true;
+
+	self->handshake_timeout = self->close_timeout = self->ping_interval = 60;
+	// This is still ridiculously high.  Note that the most significant bit
+	// must always be zero, i.e. the protocol maximum is 0x7FFF FFFF FFFF FFFF.
+	self->max_payload_len = UINT32_MAX;
+}
+
+/// Stop all timers, not going to use the handler anymore
+static void
+ws_handler_stop (struct ws_handler *self)
+{
+	ev_timer_stop (EV_DEFAULT_ &self->handshake_timeout_watcher);
+	ev_timer_stop (EV_DEFAULT_ &self->ping_timer);
+	ev_timer_stop (EV_DEFAULT_ &self->close_timeout_watcher);
+}
+
+static void
+ws_handler_free (struct ws_handler *self)
+{
+	ws_handler_stop (self);
+
+	str_free (&self->field);
+	str_free (&self->value);
+	str_map_free (&self->headers);
+	str_free (&self->url);
+
+	ws_parser_free (&self->parser);
+	str_free (&self->message_data);
+}
+
+static bool
+ws_handler_header_field_is_a_list (const char *name)
+{
+	// This must contain all header fields we use for anything
+	static const char *concatenable[] =
+		{ SEC_WS_PROTOCOL, SEC_WS_EXTENSIONS, "Connection", "Upgrade" };
+
+	for (size_t i = 0; i < N_ELEMENTS (concatenable); i++)
+		if (!strcasecmp_ascii (name, concatenable[i]))
+			return true;
+	return false;
+}
+
+static void
+ws_handler_on_header_read (struct ws_handler *self)
+{
+	// The HTTP parser unfolds values and removes preceding whitespace, but
+	// otherwise doesn't touch the values or the following whitespace.
+
+	// RFC 7230 states that trailing whitespace is not part of a field value
+	char *value = self->field.str;
+	size_t len = self->field.len;
+	while (len--)
+		if (value[len] == '\t' || value[len] == ' ')
+			value[len] = '\0';
+		else
+			break;
+	self->field.len = len;
+
+	const char *field = self->field.str;
+	const char *current = str_map_find (&self->headers, field);
+	if (ws_handler_header_field_is_a_list (field) && current)
+		str_map_set (&self->headers, field,
+			xstrdup_printf ("%s, %s", current, self->value.str));
+	else
+		// If the field cannot be concatenated, just overwrite the last value.
+		// Maybe we should issue a warning or something.
+		str_map_set (&self->headers, field, xstrdup (self->value.str));
+}
+
+static int
+ws_handler_on_header_field (http_parser *parser, const char *at, size_t len)
+{
+	struct ws_handler *self = parser->data;
+	if (self->have_header_value)
+	{
+		ws_handler_on_header_read (self);
+		str_reset (&self->field);
+		str_reset (&self->value);
+	}
+	str_append_data (&self->field, at, len);
+	self->have_header_value = false;
+	return 0;
+}
+
+static int
+ws_handler_on_header_value (http_parser *parser, const char *at, size_t len)
+{
+	struct ws_handler *self = parser->data;
+	str_append_data (&self->value, at, len);
+	self->have_header_value = true;
+	return 0;
+}
+
+static int
+ws_handler_on_headers_complete (http_parser *parser)
+{
+	struct ws_handler *self = parser->data;
+	if (self->have_header_value)
+		ws_handler_on_header_read (self);
+
+	// We strictly require a protocol upgrade
+	if (!parser->upgrade)
+		return 2;
+
+	return 0;
+}
+
+static int
+ws_handler_on_url (http_parser *parser, const char *at, size_t len)
+{
+	struct ws_handler *self = parser->data;
+	str_append_data (&self->value, at, len);
+	return 0;
+}
+
+#define HTTP_101_SWITCHING_PROTOCOLS    "101 Switching Protocols"
+#define HTTP_400_BAD_REQUEST            "400 Bad Request"
+#define HTTP_405_METHOD_NOT_ALLOWED     "405 Method Not Allowed"
+#define HTTP_417_EXPECTATION_FAILED     "407 Expectation Failed"
+#define HTTP_426_UPGRADE_REQUIRED       "426 Upgrade Required"
+#define HTTP_505_VERSION_NOT_SUPPORTED  "505 HTTP Version Not Supported"
+
+static void
+ws_handler_http_responsev (struct ws_handler *self,
+	const char *status, char *const *fields)
+{
+	hard_assert (status != NULL);
+
+	struct str response = str_make ();
+	str_append_printf (&response, "HTTP/1.1 %s\r\n", status);
+
+	while (*fields)
+		str_append_printf (&response, "%s\r\n", *fields++);
+
+	time_t now = time (NULL);
+	struct tm ts;
+	gmtime_r (&now, &ts);
+
+	// See RFC 7231, 7.1.1.2. Date
+	const char *dow[] = { "Sun", "Mon", "Tue", "Wed", "Thu", "Fri", "Sat" };
+	const char *moy[] = { "Jan", "Feb", "Mar", "Apr", "May", "Jun",
+		"Jul", "Aug", "Sep", "Oct", "Nov", "Dec" };
+	str_append_printf (&response,
+		"Date: %s, %02d %s %04d %02d:%02d:%02d GMT\r\n",
+		dow[ts.tm_wday], ts.tm_mday, moy[ts.tm_mon], ts.tm_year + 1900,
+		ts.tm_hour, ts.tm_min, ts.tm_sec);
+
+	str_append (&response, "Server: "
+		PROGRAM_NAME "/" PROGRAM_VERSION "\r\n\r\n");
+	self->write_cb (self, response.str, response.len);
+	str_free (&response);
+}
+
+static bool
+ws_handler_fail_handshake (struct ws_handler *self, const char *status, ...)
+{
+	va_list ap;
+	va_start (ap, status);
+
+	const char *s;
+	struct strv v = strv_make ();
+	while ((s = va_arg (ap, const char *)))
+		strv_append (&v, s);
+
+	va_end (ap);
+	ws_handler_http_responsev (self, status, v.vector);
+	strv_free (&v);
+
+	self->close_cb (self, true /* half_close */);
+	self->state = WS_HANDLER_FLUSHING;
+
+	if (self->on_close)
+		self->on_close (self, WS_STATUS_ABNORMAL_CLOSURE, status);
+	return false;
+}
+
+#define FAIL_HANDSHAKE(...) \
+	return ws_handler_fail_handshake (self, __VA_ARGS__, NULL)
+
+static bool
+ws_handler_finish_handshake (struct ws_handler *self)
+{
+	if (self->hp.method != HTTP_GET)
+		FAIL_HANDSHAKE (HTTP_405_METHOD_NOT_ALLOWED, "Allow: GET");
+
+	// Technically, it must be /at least/ 1.1 but no other 1.x version of HTTP
+	// is going to happen and 2.x is entirely incompatible
+	// XXX: we probably shouldn't use 505 to reject the minor version but w/e
+	if (self->hp.http_major != 1 || self->hp.http_minor != 1)
+		FAIL_HANDSHAKE (HTTP_505_VERSION_NOT_SUPPORTED);
+
+	// Your expectations are way too high
+	if (str_map_find (&self->headers, "Expect"))
+		FAIL_HANDSHAKE (HTTP_417_EXPECTATION_FAILED);
+
+	// Reject URLs specifying the schema and host; we're not parsing that
+	// TODO: actually do parse this and let our user decide if it matches
+	struct http_parser_url url;
+	if (http_parser_parse_url (self->url.str, self->url.len, false, &url)
+	 || (url.field_set & (1 << UF_SCHEMA | 1 << UF_HOST | 1 << UF_PORT))
+	 || !str_map_find (&self->headers, "Host"))
+		FAIL_HANDSHAKE (HTTP_400_BAD_REQUEST);
+
+	const char *connection = str_map_find (&self->headers, "Connection");
+	if (!connection || strcasecmp_ascii (connection, "Upgrade"))
+		FAIL_HANDSHAKE (HTTP_400_BAD_REQUEST);
+
+	// Check if we can actually upgrade the protocol to WebSockets
+	const char *upgrade = str_map_find (&self->headers, "Upgrade");
+	struct http_protocol *offered_upgrades = NULL;
+	bool can_upgrade = false;
+	if (upgrade && http_parse_upgrade (upgrade, &offered_upgrades))
+		// Case-insensitive according to RFC 6455; neither RFC 2616 nor 7230
+		// say anything at all about case-sensitivity for this field
+		LIST_FOR_EACH (struct http_protocol, iter, offered_upgrades)
+		{
+			if (!iter->version && !strcasecmp_ascii (iter->name, "websocket"))
+				can_upgrade = true;
+			http_protocol_destroy (iter);
+		}
+	if (!can_upgrade)
+		FAIL_HANDSHAKE (HTTP_426_UPGRADE_REQUIRED,
+			"Upgrade: websocket", SEC_WS_VERSION ": 13");
+
+	// Okay, we're finally past the basic HTTP/1.1 stuff
+	const char *key        = str_map_find (&self->headers, SEC_WS_KEY);
+	const char *version    = str_map_find (&self->headers, SEC_WS_VERSION);
+/*
+	const char *protocol   = str_map_find (&self->headers, SEC_WS_PROTOCOL);
+	const char *extensions = str_map_find (&self->headers, SEC_WS_EXTENSIONS);
+*/
+
+	if (!version)
+		FAIL_HANDSHAKE (HTTP_400_BAD_REQUEST);
+	if (strcmp (version, "13"))
+		FAIL_HANDSHAKE (HTTP_400_BAD_REQUEST, SEC_WS_VERSION ": 13");
+
+	struct str tmp = str_make ();
+	bool key_is_valid = key
+		&& base64_decode (key, false, &tmp) && tmp.len == 16;
+	str_free (&tmp);
+	if (!key_is_valid)
+		FAIL_HANDSHAKE (HTTP_400_BAD_REQUEST);
+
+	struct strv fields = strv_make ();
+	strv_append_args (&fields,
+		"Upgrade: websocket",
+		"Connection: Upgrade",
+		NULL);
+
+	char *response_key = ws_encode_response_key (key);
+	strv_append_owned (&fields,
+		xstrdup_printf (SEC_WS_ACCEPT ": %s", response_key));
+	free (response_key);
+
+	// TODO: make it possible to choose Sec-Websocket-{Extensions,Protocol}
+
+	ws_handler_http_responsev (self,
+		HTTP_101_SWITCHING_PROTOCOLS, fields.vector);
+
+	strv_free (&fields);
+
+	self->state = WS_HANDLER_OPEN;
+	ev_timer_init (&self->ping_timer, ws_handler_on_ping_timer,
+		self->ping_interval, 0);
+	ev_timer_start (EV_DEFAULT_ &self->ping_timer);
+	return true;
+}
+
+/// Tells the handler that the TCP connection has been established so it can
+/// timeout when the client handshake doesn't arrive soon enough
+static void
+ws_handler_start (struct ws_handler *self)
+{
+	hard_assert (self->state == WS_HANDLER_CONNECTING);
+
+	ev_timer_set (&self->handshake_timeout_watcher,
+		self->handshake_timeout, 0.);
+	ev_timer_start (EV_DEFAULT_ &self->handshake_timeout_watcher);
+}
+
+// The client should normally never close the connection, assume that it's
+// either received an EOF from our side, or that it doesn't care about our data
+// anymore, having called close() already
+static bool
+ws_handler_push_eof (struct ws_handler *self)
+{
+	switch (self->state)
+	{
+	case WS_HANDLER_CONNECTING:
+		ev_timer_stop (EV_DEFAULT_ &self->handshake_timeout_watcher);
+
+		self->state = WS_HANDLER_FLUSHING;
+		if (self->on_close)
+			self->on_close (self, WS_STATUS_ABNORMAL_CLOSURE, "unexpected EOF");
+		break;
+	case WS_HANDLER_OPEN:
+		ev_timer_stop (EV_DEFAULT_ &self->ping_timer);
+		// Fall-through
+	case WS_HANDLER_CLOSING:
+		self->state = WS_HANDLER_CLOSED;
+		if (self->on_close)
+			self->on_close (self, WS_STATUS_ABNORMAL_CLOSURE, "");
+		// Fall-through
+	case WS_HANDLER_FLUSHING:
+		ev_timer_stop (EV_DEFAULT_ &self->close_timeout_watcher);
+		break;
+	default:
+		soft_assert(self->state != WS_HANDLER_CLOSED);
+	}
+	self->state = WS_HANDLER_CLOSED;
+	return false;
+}
+
+/// Push data to the WebSocket handler.  "len == 0" means EOF.
+/// You are expected to close the connection and dispose of the handler
+/// when the function returns false.
+static bool
+ws_handler_push (struct ws_handler *self, const void *data, size_t len)
+{
+	if (!len)
+		return ws_handler_push_eof (self);
+
+	if (self->state == WS_HANDLER_FLUSHING)
+		// We're waiting for an EOF from the client, must not process data
+		return true;
+
+	if (self->state != WS_HANDLER_CONNECTING)
+		return soft_assert (self->state != WS_HANDLER_CLOSED)
+			&& ws_parser_push (&self->parser, data, len);
+
+	// The handshake hasn't been done yet, process HTTP headers
+	static const http_parser_settings http_settings =
+	{
+		.on_header_field     = ws_handler_on_header_field,
+		.on_header_value     = ws_handler_on_header_value,
+		.on_headers_complete = ws_handler_on_headers_complete,
+		.on_url              = ws_handler_on_url,
+	};
+
+	size_t n_parsed =
+		http_parser_execute (&self->hp, &http_settings, data, len);
+
+	if (self->hp.upgrade)
+	{
+		ev_timer_stop (EV_DEFAULT_ &self->handshake_timeout_watcher);
+
+		// The handshake hasn't been finished, yet there is more data
+		//   to be processed after the headers already
+		if (len - n_parsed)
+			FAIL_HANDSHAKE (HTTP_400_BAD_REQUEST);
+
+		if (!ws_handler_finish_handshake (self))
+			return false;
+		if (self->on_connected)
+			return self->on_connected (self);
+		return true;
+	}
+
+	enum http_errno err = HTTP_PARSER_ERRNO (&self->hp);
+	if (n_parsed != len || err != HPE_OK)
+	{
+		ev_timer_stop (EV_DEFAULT_ &self->handshake_timeout_watcher);
+
+		if (err == HPE_CB_headers_complete)
+			print_debug ("WS handshake failed: %s", "missing `Upgrade' field");
+		else
+			print_debug ("WS handshake failed: %s",
+				http_errno_description (err));
+
+		FAIL_HANDSHAKE (HTTP_400_BAD_REQUEST);
+	}
+	return true;
+}
+
+/// @}
+// --- Server ------------------------------------------------------------------
+
+static struct simple_config_item g_config_table[] =
+{
+	{ "bind_host",       NULL,              "Address of the server"          },
+	{ "port_fastcgi",    "9000",            "Port to bind for FastCGI"       },
+	{ "port_scgi",       NULL,              "Port to bind for SCGI"          },
+	{ "port_ws",         NULL,              "Port to bind for WebSockets"    },
+	{ "pid_file",        NULL,              "Full path for the PID file"     },
+	// XXX: here belongs something like a web SPA that interfaces with us
+	{ "static_root",     NULL,              "The root for static content"    },
+	{ NULL,              NULL,              NULL                             }
+};
+
+struct server_context
+{
+	ev_signal sigterm_watcher;          ///< Got SIGTERM
+	ev_signal sigint_watcher;           ///< Got SIGINT
+	ev_timer quit_timeout_watcher;      ///< Quit timeout watcher
+	bool quitting;                      ///< User requested quitting
+
+	struct listener *listeners;         ///< Listeners
+	size_t n_listeners;                 ///< Number of listening sockets
+
+	struct client *clients;             ///< Clients
+	unsigned n_clients;                 ///< Current number of connections
+
+	struct request_handler *handlers;   ///< Request handlers
+	struct str_map config;              ///< Server configuration
+};
+
+static void initiate_quit (struct server_context *self);
+static void try_finish_quit (struct server_context *self);
+static void on_quit_timeout (EV_P_ ev_timer *watcher, int revents);
+static void close_listeners (struct server_context *self);
+
+static void
+server_context_init (struct server_context *self)
+{
+	memset (self, 0, sizeof *self);
+
+	self->config = str_map_make (NULL);
+	simple_config_load_defaults (&self->config, g_config_table);
+	ev_timer_init (&self->quit_timeout_watcher, on_quit_timeout, 3., 0.);
+	self->quit_timeout_watcher.data = self;
+}
+
+static void
+server_context_free (struct server_context *self)
+{
+	// We really shouldn't attempt a quit without closing the clients first
+	soft_assert (!self->clients);
+
+	close_listeners (self);
+	free (self->listeners);
+
+	str_map_free (&self->config);
+}
+
+// --- JSON-RPC ----------------------------------------------------------------
+/// @defgroup JSON-RPC
+/// @{
+
+#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));
+
+	if (data)
+		json_object_set_new (error, "data", data);
+
+	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
+validate_json_rpc_content_type (const char *content_type)
+{
+	char *type = NULL;
+	char *subtype = NULL;
+
+	struct str_map parameters = str_map_make (free);
+	parameters.key_xfrm = tolower_ascii_strxfrm;
+
+	bool result = http_parse_media_type
+		(content_type, &type, &subtype, &parameters);
+	if (!result)
+		goto end;
+
+	if (strcasecmp_ascii (type, "application")
+	 || (strcasecmp_ascii (subtype, "json") &&
+		 strcasecmp_ascii (subtype, "json-rpc" /* obsolete */)))
+		result = false;
+
+	const char *charset = str_map_find (&parameters, "charset");
+	if (charset && strcasecmp_ascii (charset, "UTF-8"))
+		result = false;
+
+	// Currently ignoring all unknown parametrs
+
+end:
+	free (type);
+	free (subtype);
+	str_map_free (&parameters);
+	return result;
+}
+
+// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
+
+typedef json_t *(*json_rpc_handler_fn) (struct server_context *, json_t *);
+
+struct json_rpc_handler_info
+{
+	const char *method_name;            ///< JSON-RPC method name
+	json_rpc_handler_fn handler;        ///< Method handler
+};
+
+static int
+json_rpc_handler_info_cmp (const void *first, const void *second)
+{
+	return strcmp (((struct json_rpc_handler_info *) first)->method_name,
+		((struct json_rpc_handler_info *) second)->method_name);
+}
+
+// TODO: a method that sends a response after a certain number of seconds.
+//   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)
+{
+	// A list of all available methods; this list has to be ordered.
+	// Eventually it might be better to move this into a map in the context.
+	static struct json_rpc_handler_info handlers[] =
+	{
+		{ "ping", json_rpc_ping },
+	};
+
+	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));
+
+	struct json_rpc_handler_info key = { .method_name = method };
+	struct json_rpc_handler_info *handler = bsearch (&key, handlers,
+		N_ELEMENTS (handlers), sizeof key, json_rpc_handler_info_cmp);
+	if (!handler)
+		return json_rpc_response (id, NULL,
+			json_rpc_error (JSON_RPC_ERROR_METHOD_NOT_FOUND, NULL));
+
+	json_t *response = handler->handler (ctx, params);
+	if (id)
+		return response;
+
+	// Notifications don't get responses
+	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 ----------------------------------------------------------------
+/// @defgroup Requests
+/// @{
+
+/// A generic CGI request abstraction, writing data indirectly through callbacks
+struct request
+{
+	struct server_context *ctx;         ///< Server context
+
+	struct request_handler *handler;    ///< Assigned request handler
+	void *handler_data;                 ///< User data for the handler
+
+	/// Callback to write some CGI response data to the output
+	void (*write_cb) (struct request *, const void *data, size_t len);
+
+	/// Callback to close the CGI response, simulates end of program execution.
+	/// CALLING THIS MAY CAUSE THE REQUEST TO BE DESTROYED.
+	void (*close_cb) (struct request *);
+};
+
+/// An interface to detect and handle specific kinds of CGI requests.
+/// The server walks through a list of them until it finds one that can serve
+/// a particular request.  If unsuccessful, the remote client gets a 404
+/// (the default handling).
+struct request_handler
+{
+	LIST_HEADER (struct request_handler)
+
+	/// Install ourselves as the handler for the request, if applicable.
+	/// Sets @a continue_ to false if further processing should be stopped,
+	/// meaning the request has already been handled.
+	bool (*try_handle) (struct request *request,
+		struct str_map *headers, bool *continue_);
+
+	/// Handle incoming data.  "len == 0" means EOF.
+	/// Returns false if there is no more processing to be done.
+	// FIXME: the EOF may or may not be delivered when request is cut short,
+	//   we should fix FastCGI not to deliver it on CONTENT_LENGTH mismatch
+	bool (*push_cb) (struct request *request, const void *data, size_t len);
+
+	/// Destroy the handler's data stored in the request object
+	void (*finalize_cb) (struct request *request);
+};
+
+static void
+request_init (struct request *self)
+{
+	memset (self, 0, sizeof *self);
+}
+
+static void
+request_free (struct request *self)
+{
+	if (self->handler)
+		self->handler->finalize_cb (self);
+}
+
+/// Write request CGI response data, intended for use by request handlers
+static void
+request_write (struct request *self, const void *data, size_t len)
+{
+	self->write_cb (self, data, len);
+}
+
+/// This function is only intended to be run from asynchronous event handlers
+/// such as timers, not as a direct result of starting the request or receiving
+/// request data.  CALLING THIS MAY CAUSE THE REQUEST TO BE DESTROYED.
+static void
+request_finish (struct request *self)
+{
+	self->close_cb (self);
+}
+
+/// Starts processing a request.  Returns false if no further action is to be
+/// done and the request should be finished.
+static bool
+request_start (struct request *self, struct str_map *headers)
+{
+	// XXX: it feels like this should rather be two steps:
+	//   bool (*can_handle) (request *, headers)
+	//   ... install the handler ...
+	//   bool (*handle) (request *)
+	//
+	//   However that might cause some stuff to be done twice.
+	//
+	//   Another way we could get rid of the continue_ argument is via adding
+	//   some way of marking the request as finished from within the handler.
+
+	if (g_debug_mode)
+	{
+		struct str_map_iter iter = str_map_iter_make (headers);
+		const char *value;
+		while ((value = str_map_iter_next (&iter)))
+			print_debug ("%s: %s", iter.link->key, value);
+		print_debug ("--");
+	}
+
+	bool continue_ = true;
+	LIST_FOR_EACH (struct request_handler, handler, self->ctx->handlers)
+		if (handler->try_handle (self, headers, &continue_))
+		{
+			self->handler = handler;
+			return continue_;
+		}
+
+	// Unable to serve the request
+	struct str response = str_make ();
+	str_append (&response, "Status: 404 Not Found\n");
+	str_append (&response, "Content-Type: text/plain\n\n");
+	request_write (self, response.str, response.len);
+	str_free (&response);
+	return false;
+}
+
+static bool
+request_push (struct request *self, const void *data, size_t len)
+{
+	if (!soft_assert (self->handler))
+		// No handler, nothing to do with any data
+		return false;
+
+	return self->handler->push_cb (self, data, len);
+}
+
+/// @}
+// --- Requests handlers -------------------------------------------------------
+
+static bool
+request_handler_json_rpc_try_handle
+	(struct request *request, struct str_map *headers, bool *continue_)
+{
+	const char *content_type = str_map_find (headers, "CONTENT_TYPE");
+	const char *method = str_map_find (headers, "REQUEST_METHOD");
+
+	if (!method || strcmp (method, "POST")
+	 || !content_type || !validate_json_rpc_content_type (content_type))
+		return false;
+
+	struct str *buf = xcalloc (1, sizeof *buf);
+	*buf = str_make ();
+
+	request->handler_data = buf;
+	*continue_ = true;
+	return true;
+}
+
+static bool
+request_handler_json_rpc_push
+	(struct request *request, const void *data, size_t len)
+{
+	struct str *buf = request->handler_data;
+	if (len)
+	{
+		str_append_data (buf, data, len);
+		return true;
+	}
+
+	// TODO: check buf.len against CONTENT_LENGTH; if it's less, then the
+	//   client hasn't been successful in transferring all of its data.
+	//   See also comment on request_handler::push_cb.
+
+	struct str response = str_make ();
+	str_append (&response, "Status: 200 OK\n");
+	str_append_printf (&response, "Content-Type: %s\n\n", "application/json");
+	process_json_rpc (request->ctx, buf->str, buf->len, &response);
+	request_write (request, response.str, response.len);
+	str_free (&response);
+	return false;
+}
+
+static void
+request_handler_json_rpc_finalize (struct request *request)
+{
+	struct str *buf = request->handler_data;
+	str_free (buf);
+	free (buf);
+
+	request->handler_data = NULL;
+}
+
+struct request_handler g_request_handler_json_rpc =
+{
+	.try_handle  = request_handler_json_rpc_try_handle,
+	.push_cb     = request_handler_json_rpc_push,
+	.finalize_cb = request_handler_json_rpc_finalize,
+};
+
+// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
+
+static char *
+canonicalize_url_path (const char *path)
+{
+	// XXX: this strips any slashes at the end
+	struct strv v = strv_make ();
+	cstr_split (path, "/", true, &v);
+
+	struct strv canonical = strv_make ();
+
+	// So that the joined path always begins with a slash
+	strv_append (&canonical, "");
+
+	for (size_t i = 0; i < v.len; i++)
+	{
+		const char *dir = v.vector[i];
+		if (!strcmp (dir, "."))
+			continue;
+
+		if (strcmp (dir, ".."))
+			strv_append (&canonical, dir);
+		else if (canonical.len > 1)
+			// ".." never goes above the root
+			strv_remove (&canonical, canonical.len - 1);
+	}
+	strv_free (&v);
+
+	char *joined = strv_join (&canonical, "/");
+	strv_free (&canonical);
+	return joined;
+}
+
+static char *
+detect_magic (const void *data, size_t len)
+{
+	magic_t cookie;
+	char *mime_type = NULL;
+
+	if (!(cookie = magic_open (MAGIC_MIME)))
+		return NULL;
+
+	const char *magic = NULL;
+	if (!magic_load (cookie, NULL)
+	 && (magic = magic_buffer (cookie, data, len)))
+		mime_type = xstrdup (magic);
+	else
+		print_debug ("MIME type detection failed: %s", magic_error (cookie));
+
+	magic_close (cookie);
+	return mime_type;
+}
+
+static bool
+request_handler_static_try_handle
+	(struct request *request, struct str_map *headers, bool *continue_)
+{
+	// Serving static files is actually quite complicated as it turns out;
+	// but this is only meant to serve a few tiny text files
+
+	struct server_context *ctx = request->ctx;
+	const char *root = str_map_find (&ctx->config, "static_root");
+	if (!root)
+	{
+		print_debug ("static document root not configured");
+		return false;
+	}
+
+	// TODO: implement HEAD, we don't get that for free;
+	//   probably implies adding Content-Length
+	const char *method = str_map_find (headers, "REQUEST_METHOD");
+	if (!method || strcmp (method, "GET"))
+		return false;
+
+	// TODO: look at <SCRIPT_NAME, PATH_INFO>, REQUEST_URI in the headers
+	const char *path_info = str_map_find (headers, "PATH_INFO");
+	if (!path_info)
+		path_info = str_map_find (headers, "REQUEST_URI");
+	if (!path_info)
+	{
+		print_debug ("neither PATH_INFO nor REQUEST_URI was defined");
+		return false;
+	}
+
+	// We need to filter the path to stay in our root
+	// Being able to read /etc/passwd would be rather embarrasing
+	char *suffix = canonicalize_url_path (path_info);
+	char *path = xstrdup_printf ("%s%s", root, suffix);
+	print_debug ("trying to statically serve %s", path);
+
+	// TODO: check that this is a regular file
+	FILE *fp = fopen (path, "rb");
+	if (!fp)
+	{
+		struct str response = str_make ();
+		str_append (&response, "Status: 404 Not Found\n");
+		str_append (&response, "Content-Type: text/plain\n\n");
+		str_append_printf (&response,
+			"File %s was not found on this server\n", suffix);
+		request_write (request, response.str, response.len);
+		str_free (&response);
+
+		free (suffix);
+		free (path);
+		return false;
+	}
+
+	free (suffix);
+	free (path);
+
+	uint8_t buf[8192];
+	size_t len;
+
+	// Try to detect the Content-Type from the actual contents
+	char *mime_type = NULL;
+	if ((len = fread (buf, 1, sizeof buf, fp)))
+		mime_type = detect_magic (buf, len);
+	if (!mime_type)
+		mime_type = xstrdup ("application/octet_stream");
+
+	struct str response = str_make ();
+	str_append (&response, "Status: 200 OK\n");
+	str_append_printf (&response, "Content-Type: %s\n\n", mime_type);
+	request_write (request, response.str, response.len);
+	str_free (&response);
+	free (mime_type);
+
+	// Write the chunk we've used to help us with magic detection;
+	// obviously we have to do it after we've written the headers
+	if (len)
+		request_write (request, buf, len);
+
+	while ((len = fread (buf, 1, sizeof buf, fp)))
+		request_write (request, buf, len);
+	fclose (fp);
+
+	// TODO: this should rather not be returned all at once but in chunks;
+	//   file read requests never return EAGAIN
+	// TODO: actual file data should really be returned by a callback when
+	//   the socket is writable with nothing to be sent (pumping the entire
+	//   file all at once won't really work if it's huge).
+	*continue_ = false;
+	return true;
+}
+
+static bool
+request_handler_static_push
+	(struct request *request, const void *data, size_t len)
+{
+	(void) request;
+	(void) data;
+
+	// Aborting on content; we shouldn't receive any (GET)
+	// FIXME: there should at least be some indication of this happening
+	return len == 0;
+}
+
+static void
+request_handler_static_finalize (struct request *request)
+{
+	(void) request;
+	// Nothing to dispose of this far
+}
+
+struct request_handler g_request_handler_static =
+{
+	.try_handle  = request_handler_static_try_handle,
+	.push_cb     = request_handler_static_push,
+	.finalize_cb = request_handler_static_finalize,
+};
+
+// --- Client communication handlers -------------------------------------------
+
+/// A virtual class for client connections coming either from the web server
+/// or directly from the end-client, depending on the protocol in use
+struct client
+{
+	LIST_HEADER (struct client)
+
+	struct client_vtable *vtable;       ///< Client behaviour
+
+	int socket_fd;                      ///< The network socket
+	bool received_eof;                  ///< Whether EOF has been received yet
+	bool flushing;                      ///< No more data to write, send FIN
+	bool closing;                       ///< No more data to read or write
+	bool half_closed;                   ///< Conn. half-closed while flushing
+	struct write_queue write_queue;     ///< Write queue
+	ev_timer close_timeout_watcher;     ///< Write queue flush timer
+
+	ev_io read_watcher;                 ///< The socket can be read from
+	ev_io write_watcher;                ///< The socket can be written to
+};
+
+/// The concrete behaviour to serve a particular client's requests
+struct client_vtable
+{
+	/// Process incoming data; "len == 0" means EOF.
+	/// If the method returns false, client_close() is called by the caller.
+	bool (*push) (struct client *client, const void *data, size_t len);
+
+	// TODO: optional push_error() to inform about network I/O errors
+
+	/// Attempt a graceful shutdown: make any appropriate steps before
+	/// the client connection times out and gets torn down by force.
+	/// The client is allowed to destroy itself immediately.
+	void (*shutdown) (struct client *client);
+
+	/// Do any additional cleanup for the concrete class before destruction
+	void (*finalize) (struct client *client);
+};
+
+static void
+client_destroy (struct client *self)
+{
+	// XXX: this codebase halfway pretends there could be other contexts
+	struct server_context *ctx = ev_userdata (EV_DEFAULT);
+	LIST_UNLINK (ctx->clients, self);
+	ctx->n_clients--;
+
+	// First uninitialize the higher-level implementation
+	self->vtable->finalize (self);
+
+	ev_io_stop (EV_DEFAULT_ &self->read_watcher);
+	ev_io_stop (EV_DEFAULT_ &self->write_watcher);
+	xclose (self->socket_fd);
+	write_queue_free (&self->write_queue);
+	ev_timer_stop (EV_DEFAULT_ &self->close_timeout_watcher);
+	free (self);
+
+	try_finish_quit (ctx);
+}
+
+static void
+client_write (struct client *self, const void *data, size_t len)
+{
+	if (!soft_assert (!self->flushing) || len == 0)
+		return;
+
+	struct write_req *req = xcalloc (1, sizeof *req);
+	req->data.iov_base = memcpy (xmalloc (len), data, len);
+	req->data.iov_len = len;
+
+	write_queue_add (&self->write_queue, req);
+	ev_io_start (EV_DEFAULT_ &self->write_watcher);
+}
+
+/// Half-close the connection from our side once the write_queue is flushed.
+/// It is the caller's responsibility to destroy the connection upon EOF.
+// XXX: or we might change on_client_readable to do it anyway, seems safe
+static void
+client_shutdown (struct client *self)
+{
+	self->flushing = true;
+	ev_feed_event (EV_DEFAULT_ &self->write_watcher, EV_WRITE);
+}
+
+/// Try to cleanly close the connection, waiting for the remote client to close
+/// its own side of the connection as a sign that it has processed all the data
+/// it wanted to.  The client implementation will not receive any further data.
+/// May directly call client_destroy().
+static void
+client_close (struct client *self)
+{
+	if (self->closing)
+		return;
+
+	self->closing = true;
+	ev_timer_start (EV_DEFAULT_ &self->close_timeout_watcher);
+	client_shutdown (self);
+
+	// We assume the remote client doesn't want our data if it half-closes
+	if (self->received_eof)
+		client_destroy (self);
+}
+
+// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
+
+static bool
+client_read_loop (EV_P_ struct client *client, ev_io *watcher)
+{
+	char buf[8192];
+	ssize_t n_read;
+again:
+	while ((n_read = recv (watcher->fd, buf, sizeof buf, 0)) >= 0)
+	{
+		if (!n_read)
+		{
+			// Don't deliver the EOF condition repeatedly
+			ev_io_stop (EV_A_ watcher);
+			client->received_eof = true;
+		}
+		if (!client->closing
+		 && !client->vtable->push (client, buf, n_read))
+		{
+			client_close (client);
+			return false;
+		}
+		if (!n_read)
+			return true;
+	}
+	if (errno == EINTR)
+		goto again;
+	if (errno == EAGAIN)
+		return true;
+
+	client_destroy (client);
+	return false;
+}
+
+static void
+on_client_readable (EV_P_ ev_io *watcher, int revents)
+{
+	struct client *client = watcher->data;
+	(void) revents;
+
+	if (client_read_loop (EV_A_ client, watcher)
+	 && client->closing && client->received_eof)
+		client_destroy (client);
+}
+
+static void
+on_client_writable (EV_P_ ev_io *watcher, int revents)
+{
+	struct client *client = watcher->data;
+	(void) loop;
+	(void) revents;
+
+	// TODO: some sort of "on_buffers_flushed" callback for streaming huge
+	//   chunks of external (or generated) data.  That will need to be
+	//   forwarded to "struct request_handler".
+	if (!flush_queue (&client->write_queue, watcher->fd))
+	{
+		client_destroy (client);
+		return;
+	}
+	if (!write_queue_is_empty (&client->write_queue))
+		return;
+
+	ev_io_stop (EV_A_ watcher);
+	if (client->flushing && !client->half_closed)
+	{
+		if (!shutdown (client->socket_fd, SHUT_WR))
+			client->half_closed = true;
+		else
+			client_destroy (client);
+	}
+}
+
+static void
+on_client_timeout (EV_P_ ev_timer *watcher, int revents)
+{
+	(void) loop;
+	(void) revents;
+
+	client_destroy (watcher->data);
+}
+
+/// Create a new instance of a subclass with the given size.
+/// The superclass is assumed to be the first member of the structure.
+static void *
+client_new (EV_P_ size_t size, int sock_fd)
+{
+	struct server_context *ctx = ev_userdata (loop);
+	struct client *self = xcalloc (1, size);
+
+	self->write_queue = write_queue_make ();
+	ev_timer_init (&self->close_timeout_watcher, on_client_timeout, 5., 0.);
+	self->close_timeout_watcher.data = self;
+
+	set_blocking (sock_fd, false);
+	self->socket_fd = sock_fd;
+
+	ev_io_init (&self->read_watcher,  on_client_readable, sock_fd, EV_READ);
+	ev_io_init (&self->write_watcher, on_client_writable, sock_fd, EV_WRITE);
+	self->read_watcher.data = self;
+	self->write_watcher.data = self;
+
+	// We're only interested in reading as the write queue is empty now
+	ev_io_start (EV_A_ &self->read_watcher);
+
+	LIST_PREPEND (ctx->clients, self);
+	ctx->n_clients++;
+	return self;
+}
+
+// --- FastCGI client handler --------------------------------------------------
+
+struct client_fcgi
+{
+	struct client client;               ///< Parent class
+	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_cb (struct request *req, const void *data, size_t len)
+{
+	FIND_CONTAINER (self, req, struct client_fcgi_request, request);
+	fcgi_request_write (self->fcgi_request, data, len);
+}
+
+static void
+client_fcgi_request_close_cb (struct request *req)
+{
+	FIND_CONTAINER (self, req, struct client_fcgi_request, request);
+	struct fcgi_muxer *muxer = self->fcgi_request->muxer;
+	// No more data to send, terminate the substream/request,
+	// and also the transport if the client didn't specifically ask to keep it
+	if (!fcgi_request_finish (self->fcgi_request))
+		muxer->close_cb (muxer);
+}
+
+// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
+
+static bool
+client_fcgi_request_start (struct fcgi_request *fcgi_request)
+{
+	struct client_fcgi_request *request =
+		fcgi_request->handler_data = xcalloc (1, sizeof *request);
+	request->fcgi_request = fcgi_request;
+	request_init (&request->request);
+	request->request.ctx = ev_userdata (EV_DEFAULT);
+	request->request.write_cb = client_fcgi_request_write_cb;
+	request->request.close_cb = client_fcgi_request_close_cb;
+
+	return request_start (&request->request, &fcgi_request->headers);
+}
+
+static bool
+client_fcgi_request_push
+	(struct fcgi_request *req, const void *data, size_t len)
+{
+	struct client_fcgi_request *request = req->handler_data;
+	return request_push (&request->request, data, len)
+		|| fcgi_request_finish (req);
+}
+
+static void
+client_fcgi_request_finalize (struct fcgi_request *req)
+{
+	struct client_fcgi_request *request = req->handler_data;
+	request_free (&request->request);
+	free (request);
+}
+
+// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
+
+static void
+client_fcgi_write_cb (struct fcgi_muxer *mux, const void *data, size_t len)
+{
+	FIND_CONTAINER (self, mux, struct client_fcgi, muxer);
+	client_write (&self->client, data, len);
+}
+
+static void
+client_fcgi_close_cb (struct fcgi_muxer *mux)
+{
+	FIND_CONTAINER (self, mux, struct client_fcgi, muxer);
+	client_close (&self->client);
+}
+
+// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
+
+static bool
+client_fcgi_push (struct client *client, const void *data, size_t len)
+{
+	FIND_CONTAINER (self, client, struct client_fcgi, client);
+	return fcgi_muxer_push (&self->muxer, data, len);
+}
+
+static void
+client_fcgi_shutdown (struct client *client)
+{
+	FIND_CONTAINER (self, client, struct client_fcgi, client);
+	self->muxer.in_shutdown = true;
+
+	// TODO: respond with FCGI_END_REQUEST: FCGI_REQUEST_COMPLETE to everything?
+	//   The FastCGI specification isn't very clear about what we should do.
+}
+
+static void
+client_fcgi_finalize (struct client *client)
+{
+	FIND_CONTAINER (self, client, struct client_fcgi, client);
+	fcgi_muxer_free (&self->muxer);
+}
+
+static struct client_vtable client_fcgi_vtable =
+{
+	.push     = client_fcgi_push,
+	.shutdown = client_fcgi_shutdown,
+	.finalize = client_fcgi_finalize,
+};
+
+static struct client *
+client_fcgi_create (EV_P_ int sock_fd)
+{
+	struct client_fcgi *self = client_new (EV_A_ sizeof *self, sock_fd);
+	self->client.vtable = &client_fcgi_vtable;
+
+	fcgi_muxer_init (&self->muxer);
+	self->muxer.write_cb            = client_fcgi_write_cb;
+	self->muxer.close_cb            = client_fcgi_close_cb;
+	self->muxer.request_start_cb    = client_fcgi_request_start;
+	self->muxer.request_push_cb     = client_fcgi_request_push;
+	self->muxer.request_finalize_cb = client_fcgi_request_finalize;
+	return &self->client;
+}
+
+// --- SCGI client handler -----------------------------------------------------
+
+struct client_scgi
+{
+	struct client client;               ///< Parent class
+	struct scgi_parser parser;          ///< SCGI stream parser
+	struct request request;             ///< Request (only one per connection)
+	unsigned long remaining_content;    ///< Length of input data to be seen
+};
+
+static void
+client_scgi_write_cb (struct request *req, const void *data, size_t len)
+{
+	FIND_CONTAINER (self, req, struct client_scgi, request);
+	client_write (&self->client, data, len);
+}
+
+static void
+client_scgi_close_cb (struct request *req)
+{
+	FIND_CONTAINER (self, req, struct client_scgi, request);
+	// NOTE: this rather really means "close me [the request]"
+	client_close (&self->client);
+}
+
+static bool
+client_scgi_on_headers_read (void *user_data)
+{
+	struct client_scgi *self = user_data;
+	const char *cl = str_map_find (&self->parser.headers, "CONTENT_LENGTH");
+	if (!cl || !xstrtoul (&self->remaining_content, cl, 10))
+	{
+		print_debug ("SCGI request with invalid or missing CONTENT_LENGTH");
+		return false;
+	}
+	return request_start (&self->request, &self->parser.headers);
+}
+
+static bool
+client_scgi_on_content (void *user_data, const void *data, size_t len)
+{
+	struct client_scgi *self = user_data;
+	if (len > self->remaining_content)
+	{
+		print_debug ("SCGI request got more data than CONTENT_LENGTH");
+		return false;
+	}
+	// We're in a slight disagreement with the specification since
+	// this tries to write output before it has read all the input
+	if (!request_push (&self->request, data, len))
+		return false;
+
+	// Signalise end of input to the request handler
+	return (self->remaining_content -= len) != 0
+		|| request_push (&self->request, NULL, 0);
+}
+
+// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
+
+static bool
+client_scgi_push (struct client *client, const void *data, size_t len)
+{
+	struct client_scgi *self = (struct client_scgi *) client;
+	struct error *e = NULL;
+	if (scgi_parser_push (&self->parser, data, len, &e))
+		return true;
+
+	if (e != NULL)
+	{
+		print_debug ("SCGI parser failed: %s", e->message);
+		error_free (e);
+	}
+	return false;
+}
+
+static void
+client_scgi_finalize (struct client *client)
+{
+	struct client_scgi *self = (struct client_scgi *) client;
+	request_free (&self->request);
+	scgi_parser_free (&self->parser);
+}
+
+static struct client_vtable client_scgi_vtable =
+{
+	.push     = client_scgi_push,
+	.finalize = client_scgi_finalize,
+};
+
+static struct client *
+client_scgi_create (EV_P_ int sock_fd)
+{
+	struct client_scgi *self = client_new (EV_A_ sizeof *self, sock_fd);
+	self->client.vtable = &client_scgi_vtable;
+
+	request_init (&self->request);
+	self->request.ctx            = ev_userdata (EV_DEFAULT);
+	self->request.write_cb       = client_scgi_write_cb;
+	self->request.close_cb       = client_scgi_close_cb;
+
+	self->parser = scgi_parser_make ();
+	self->parser.on_headers_read = client_scgi_on_headers_read;
+	self->parser.on_content      = client_scgi_on_content;
+	self->parser.user_data       = self;
+	return &self->client;
+}
+
+// --- WebSockets client handler -----------------------------------------------
+
+struct client_ws
+{
+	struct client client;               ///< Parent class
+	struct ws_handler handler;          ///< WebSockets connection handler
+};
+
+static bool
+client_ws_on_message (struct ws_handler *handler,
+	enum ws_opcode type, const void *data, size_t len)
+{
+	FIND_CONTAINER (self, handler, struct client_ws, handler);
+	if (type != WS_OPCODE_TEXT)
+	{
+		return ws_handler_fail_connection
+			(&self->handler, WS_STATUS_UNSUPPORTED_DATA);
+	}
+
+	struct server_context *ctx = ev_userdata (EV_DEFAULT);
+	struct str response = str_make ();
+	process_json_rpc (ctx, data, len, &response);
+	if (response.len)
+		ws_handler_send_frame (&self->handler,
+			WS_OPCODE_TEXT, response.str, response.len);
+	str_free (&response);
+	return true;
+}
+
+static void
+client_ws_write_cb (struct ws_handler *handler, const void *data, size_t len)
+{
+	FIND_CONTAINER (self, handler, struct client_ws, handler);
+	client_write (&self->client, data, len);
+}
+
+static void
+client_ws_close_cb (struct ws_handler *handler, bool half_close)
+{
+	FIND_CONTAINER (self, handler, struct client_ws, handler);
+	(half_close ? client_shutdown : client_destroy) (&self->client);
+}
+
+// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
+
+static bool
+client_ws_push (struct client *client, const void *data, size_t len)
+{
+	FIND_CONTAINER (self, client, struct client_ws, client);
+	// client_close() will correctly destroy the client on EOF
+	return ws_handler_push (&self->handler, data, len);
+}
+
+static void
+client_ws_shutdown (struct client *client)
+{
+	FIND_CONTAINER (self, client, struct client_ws, client);
+	if (self->handler.state == WS_HANDLER_CONNECTING)
+		// No on_close, no problem
+		client_destroy (&self->client);
+	else if (self->handler.state == WS_HANDLER_OPEN)
+		ws_handler_close (&self->handler, WS_STATUS_GOING_AWAY, NULL, 0);
+}
+
+static void
+client_ws_finalize (struct client *client)
+{
+	FIND_CONTAINER (self, client, struct client_ws, client);
+	ws_handler_free (&self->handler);
+}
+
+static struct client_vtable client_ws_vtable =
+{
+	.push     = client_ws_push,
+	.shutdown = client_ws_shutdown,
+	.finalize = client_ws_finalize,
+};
+
+static struct client *
+client_ws_create (EV_P_ int sock_fd)
+{
+	struct client_ws *self = client_new (EV_A_ sizeof *self, sock_fd);
+	self->client.vtable = &client_ws_vtable;
+
+	ws_handler_init (&self->handler);
+	self->handler.on_message = client_ws_on_message;
+	self->handler.write_cb   = client_ws_write_cb;
+	self->handler.close_cb   = client_ws_close_cb;
+
+	// One mebibyte seems to be a reasonable value
+	self->handler.max_payload_len = 1 << 10;
+
+	ws_handler_start (&self->handler);
+	return &self->client;
+}
+
+// --- Basic server stuff ------------------------------------------------------
+
+typedef struct client *(*client_create_fn) (EV_P_ int sock_fd);
+
+struct listener
+{
+	int fd;                             ///< Listening socket FD
+	ev_io watcher;                      ///< New connection available
+	client_create_fn create;            ///< Client constructor
+};
+
+static void
+close_listeners (struct server_context *self)
+{
+	for (size_t i = 0; i < self->n_listeners; i++)
+	{
+		struct listener *listener = &self->listeners[i];
+		if (listener->fd == -1)
+			continue;
+
+		ev_io_stop (EV_DEFAULT_ &listener->watcher);
+		xclose (listener->fd);
+		listener->fd = -1;
+	}
+}
+
+static void
+try_finish_quit (struct server_context *self)
+{
+	if (!self->quitting || self->clients)
+		return;
+
+	ev_timer_stop (EV_DEFAULT_ &self->quit_timeout_watcher);
+	ev_break (EV_DEFAULT_ EVBREAK_ALL);
+}
+
+static void
+on_quit_timeout (EV_P_ ev_timer *watcher, int revents)
+{
+	struct server_context *self = watcher->data;
+	(void) loop;
+	(void) revents;
+
+	LIST_FOR_EACH (struct client, iter, self->clients)
+		client_destroy (iter);
+}
+
+static void
+initiate_quit (struct server_context *self)
+{
+	self->quitting = true;
+	close_listeners (self);
+
+	// Wait a little while for all clients to clean up, if necessary
+	LIST_FOR_EACH (struct client, iter, self->clients)
+		if (iter->vtable->shutdown)
+			iter->vtable->shutdown (iter);
+	ev_timer_start (EV_DEFAULT_ &self->quit_timeout_watcher);
+	try_finish_quit (self);
+}
+
+static void
+on_client_available (EV_P_ ev_io *watcher, int revents)
+{
+	struct server_context *ctx = ev_userdata (loop);
+	struct listener *listener = watcher->data;
+	(void) revents;
+
+	while (true)
+	{
+		int sock_fd = accept (watcher->fd, NULL, NULL);
+		if (sock_fd != -1)
+			listener->create (EV_A_ sock_fd);
+		else if (errno == EAGAIN)
+			return;
+		else if (errno != EINTR && errno != EMFILE
+		 && errno != ECONNRESET && errno != ECONNABORTED)
+			break;
+	}
+
+	// Stop accepting connections to prevent busy looping
+	ev_io_stop (EV_A_ watcher);
+
+	print_fatal ("%s: %s", "accept", strerror (errno));
+	initiate_quit (ctx);
+}
+
+// --- Application setup -------------------------------------------------------
+
+/// This function handles values that require validation before their first use,
+/// or some kind of a transformation (such as conversion to an integer) needs
+/// to be done before they can be used directly.
+static bool
+parse_config (struct server_context *ctx, struct error **e)
+{
+	(void) ctx;
+	(void) e;
+
+	return true;
+}
+
+static int
+listener_bind (struct addrinfo *gai_iter)
+{
+	int fd = socket (gai_iter->ai_family,
+		gai_iter->ai_socktype, gai_iter->ai_protocol);
+	if (fd == -1)
+		return -1;
+	set_cloexec (fd);
+
+	int yes = 1;
+	soft_assert (setsockopt (fd, SOL_SOCKET, SO_KEEPALIVE,
+		&yes, sizeof yes) != -1);
+	soft_assert (setsockopt (fd, SOL_SOCKET, SO_REUSEADDR,
+		&yes, sizeof yes) != -1);
+
+	char host[NI_MAXHOST], port[NI_MAXSERV];
+	host[0] = port[0] = '\0';
+	int err = getnameinfo (gai_iter->ai_addr, gai_iter->ai_addrlen,
+		host, sizeof host, port, sizeof port,
+		NI_NUMERICHOST | NI_NUMERICSERV);
+	if (err)
+		print_debug ("%s: %s", "getnameinfo", gai_strerror (err));
+
+	char *address = format_host_port_pair (host, port);
+	if (bind (fd, gai_iter->ai_addr, gai_iter->ai_addrlen))
+		print_error ("bind to %s failed: %s", address, strerror (errno));
+	else if (listen (fd, 16 /* arbitrary number */))
+		print_error ("listen on %s failed: %s", address, strerror (errno));
+	else
+	{
+		print_status ("listening on %s", address);
+		free (address);
+		return fd;
+	}
+
+	free (address);
+	xclose (fd);
+	return -1;
+}
+
+static void
+listener_add (struct server_context *ctx, const char *host, const char *port,
+	const struct addrinfo *gai_hints, client_create_fn create)
+{
+	struct addrinfo *gai_result, *gai_iter;
+	int err = getaddrinfo (host, port, gai_hints, &gai_result);
+	if (err)
+	{
+		char *address = format_host_port_pair (host, port);
+		print_error ("bind to %s failed: %s: %s",
+			address, "getaddrinfo", gai_strerror (err));
+		free (address);
+		return;
+	}
+
+	int fd;
+	for (gai_iter = gai_result; gai_iter; gai_iter = gai_iter->ai_next)
+	{
+		if ((fd = listener_bind (gai_iter)) == -1)
+			continue;
+		set_blocking (fd, false);
+
+		struct listener *listener = &ctx->listeners[ctx->n_listeners++];
+		ev_io_init (&listener->watcher, on_client_available, fd, EV_READ);
+		ev_io_start (EV_DEFAULT_ &listener->watcher);
+		listener->watcher.data = listener;
+		listener->create = create;
+		listener->fd = fd;
+		break;
+	}
+	freeaddrinfo (gai_result);
+}
+
+static void
+get_ports_from_config (struct server_context *ctx,
+	const char *key, struct strv *out)
+{
+	const char *ports;
+	if ((ports = str_map_find (&ctx->config, key)))
+		cstr_split (ports, ",", true, out);
+}
+
+static bool
+setup_listen_fds (struct server_context *ctx, struct error **e)
+{
+	static const struct addrinfo gai_hints =
+	{
+		.ai_socktype = SOCK_STREAM,
+		.ai_flags = AI_PASSIVE,
+	};
+
+	struct strv ports_fcgi = strv_make ();
+	struct strv ports_scgi = strv_make ();
+	struct strv ports_ws   = strv_make ();
+
+	get_ports_from_config (ctx, "port_fastcgi", &ports_fcgi);
+	get_ports_from_config (ctx, "port_scgi",    &ports_scgi);
+	get_ports_from_config (ctx, "port_ws",      &ports_ws);
+
+	const char *bind_host = str_map_find (&ctx->config, "bind_host");
+	size_t n_ports = ports_fcgi.len + ports_scgi.len + ports_ws.len;
+	ctx->listeners = xcalloc (n_ports, sizeof *ctx->listeners);
+
+	for (size_t i = 0; i < ports_fcgi.len; i++)
+		listener_add (ctx, bind_host, ports_fcgi.vector[i],
+			&gai_hints, client_fcgi_create);
+	for (size_t i = 0; i < ports_scgi.len; i++)
+		listener_add (ctx, bind_host, ports_scgi.vector[i],
+			&gai_hints, client_scgi_create);
+	for (size_t i = 0; i < ports_ws.len; i++)
+		listener_add (ctx, bind_host, ports_ws.vector[i],
+			&gai_hints, client_ws_create);
+
+	strv_free (&ports_fcgi);
+	strv_free (&ports_scgi);
+	strv_free (&ports_ws);
+
+	if (!ctx->n_listeners)
+	{
+		error_set (e, "%s: %s",
+			"network setup failed", "no ports to listen on");
+		return false;
+	}
+	return true;
+}
+
+static bool
+app_lock_pid_file (struct server_context *ctx, struct error **e)
+{
+	const char *path = str_map_find (&ctx->config, "pid_file");
+	if (!path)
+		return true;
+
+	char *resolved = resolve_filename (path, resolve_relative_runtime_filename);
+	bool result = lock_pid_file (resolved, e) != -1;
+	free (resolved);
+	return result;
+}
+
+// --- Tests -------------------------------------------------------------------
+
+static void
+test_misc (void)
+{
+	soft_assert ( validate_json_rpc_content_type
+		("application/JSON; charset=\"utf-8\""));
+	soft_assert (!validate_json_rpc_content_type
+		("text/html; charset=\"utf-8\""));
+
+	char *canon = canonicalize_url_path ("///../../../etc/./passwd");
+	soft_assert (!strcmp (canon, "/etc/passwd"));
+	free (canon);
+}
+
+int
+test_main (int argc, char *argv[])
+{
+	struct test test;
+	test_init (&test, argc, argv);
+
+	test_add_simple (&test, "/misc",        NULL, test_misc);
+
+	// TODO: write more tests
+	// TODO: test the server handler (happy path)
+
+	return test_run (&test);
+}
+
+// --- Main program ------------------------------------------------------------
+
+static void
+on_termination_signal (EV_P_ ev_signal *handle, int revents)
+{
+	struct server_context *ctx = ev_userdata (loop);
+	(void) handle;
+	(void) revents;
+
+	if (ctx->quitting)
+	{
+		// Double C-c from the terminal accelerates the process
+		LIST_FOR_EACH (struct client, iter, ctx->clients)
+			client_destroy (iter);
+	}
+	else
+		initiate_quit (ctx);
+}
+
+static void
+setup_signal_handlers (struct server_context *ctx)
+{
+	ev_signal_init (&ctx->sigterm_watcher, on_termination_signal, SIGTERM);
+	ev_signal_start (EV_DEFAULT_ &ctx->sigterm_watcher);
+
+	ev_signal_init (&ctx->sigint_watcher, on_termination_signal, SIGINT);
+	ev_signal_start (EV_DEFAULT_ &ctx->sigint_watcher);
+
+	(void) signal (SIGPIPE, SIG_IGN);
+}
+
+static void
+daemonize (struct server_context *ctx)
+{
+	print_status ("daemonizing...");
+
+	if (chdir ("/"))
+		exit_fatal ("%s: %s", "chdir", strerror (errno));
+
+	// Because of systemd, we need to exit the parent process _after_ writing
+	// a PID file, otherwise our grandchild would receive a SIGTERM
+	int sync_pipe[2];
+	if (pipe (sync_pipe))
+		exit_fatal ("%s: %s", "pipe", strerror (errno));
+
+	pid_t pid;
+	if ((pid = fork ()) < 0)
+		exit_fatal ("%s: %s", "fork", strerror (errno));
+	else if (pid)
+	{
+		// Wait until all write ends of the pipe are closed, which can mean
+		// either success or failure, we don't need to care
+		xclose (sync_pipe[PIPE_WRITE]);
+
+		char dummy;
+		if (read (sync_pipe[PIPE_READ], &dummy, 1) < 0)
+			exit_fatal ("%s: %s", "read", strerror (errno));
+
+		exit (EXIT_SUCCESS);
+	}
+
+	setsid ();
+	signal (SIGHUP, SIG_IGN);
+
+	if ((pid = fork ()) < 0)
+		exit_fatal ("%s: %s", "fork", strerror (errno));
+	else if (pid)
+		exit (EXIT_SUCCESS);
+
+	openlog (PROGRAM_NAME, LOG_NDELAY | LOG_NOWAIT | LOG_PID, 0);
+	g_log_message_real = log_message_syslog;
+
+	// Write the PID file (if so configured) and get rid of the pipe, so that
+	// the read() in our grandparent finally returns zero (no write ends)
+	struct error *e = NULL;
+	if (!app_lock_pid_file (ctx, &e))
+		exit_fatal ("%s", e->message);
+
+	xclose (sync_pipe[PIPE_READ]);
+	xclose (sync_pipe[PIPE_WRITE]);
+
+	// XXX: we may close our own descriptors this way, crippling ourselves;
+	//   there is no real guarantee that we will start with all three
+	//   descriptors open.  In theory we could try to enumerate the descriptors
+	//   at the start of main().
+	for (int i = 0; i < 3; i++)
+		xclose (i);
+
+	int tty = open ("/dev/null", O_RDWR);
+	if (tty != 0 || dup (0) != 1 || dup (0) != 2)
+		exit_fatal ("failed to reopen FD's: %s", strerror (errno));
+}
+
+static void
+parse_program_arguments (int argc, char **argv)
+{
+	static const struct opt opts[] =
+	{
+		{ 't', "test", NULL, 0, "self-test" },
+		{ 'd', "debug", NULL, 0, "run in debug mode" },
+		{ 'h', "help", NULL, 0, "display this help and exit" },
+		{ 'V', "version", NULL, 0, "output version information and exit" },
+		{ 'w', "write-default-cfg", "FILENAME",
+		  OPT_OPTIONAL_ARG | OPT_LONG_ONLY,
+		  "write a default configuration file and exit" },
+		{ 0, NULL, NULL, 0, NULL }
+	};
+
+	struct opt_handler oh =
+		opt_handler_make (argc, argv, opts, NULL, "JSON-RPC 2.0 demo server.");
+
+	int c;
+	while ((c = opt_handler_get (&oh)) != -1)
+	switch (c)
+	{
+	case 't':
+		test_main (argc, argv);
+		exit (EXIT_SUCCESS);
+	case 'd':
+		g_debug_mode = true;
+		break;
+	case 'h':
+		opt_handler_usage (&oh, stdout);
+		exit (EXIT_SUCCESS);
+	case 'V':
+		printf (PROGRAM_NAME " " PROGRAM_VERSION "\n");
+		exit (EXIT_SUCCESS);
+	case 'w':
+		call_simple_config_write_default (optarg, g_config_table);
+		exit (EXIT_SUCCESS);
+	default:
+		print_error ("wrong options");
+		opt_handler_usage (&oh, stderr);
+		exit (EXIT_FAILURE);
+	}
+
+	argc -= optind;
+	argv += optind;
+
+	if (argc)
+	{
+		opt_handler_usage (&oh, stderr);
+		exit (EXIT_FAILURE);
+	}
+	opt_handler_free (&oh);
+}
+
+int
+main (int argc, char *argv[])
+{
+	parse_program_arguments (argc, argv);
+
+	print_status (PROGRAM_NAME " " PROGRAM_VERSION " starting");
+
+	struct server_context ctx;
+	server_context_init (&ctx);
+
+	struct error *e = NULL;
+	if (!simple_config_update_from_file (&ctx.config, &e))
+	{
+		print_error ("error loading configuration: %s", e->message);
+		error_free (e);
+		exit (EXIT_FAILURE);
+	}
+
+	struct ev_loop *loop;
+	if (!(loop = EV_DEFAULT))
+		exit_fatal ("libev initialization failed");
+
+	ev_set_userdata (loop, &ctx);
+	setup_signal_handlers (&ctx);
+
+	LIST_PREPEND (ctx.handlers, &g_request_handler_static);
+	LIST_PREPEND (ctx.handlers, &g_request_handler_json_rpc);
+
+	if (!parse_config (&ctx, &e)
+	 || !setup_listen_fds (&ctx, &e))
+	{
+		print_error ("%s", e->message);
+		error_free (e);
+		exit (EXIT_FAILURE);
+	}
+
+	if (!g_debug_mode)
+		daemonize (&ctx);
+	else if (!app_lock_pid_file (&ctx, &e))
+		exit_fatal ("%s", e->message);
+
+	ev_run (loop, 0);
+	ev_loop_destroy (loop);
+
+	server_context_free (&ctx);
+	return EXIT_SUCCESS;
+}
diff --git a/liberty b/liberty
-Subproject bb30c7d86ef7b165c5e00cc8e0ad2e3e85b9e61
+Subproject bca7167d037d857448cb18243425d7c61de3bdd