Move the MPD client interface to liberty

It seems like there aren't going to be any big changes any time soon.

3 files changed, 1 insertions, 655 deletions

diff --git a/liberty b/liberty
-Subproject dc54db906945ac1db84582caeb4c47d4cb89acb
+Subproject 2a15b1de700eb4e20c6bebb9742c8e20fffc968
diff --git a/mpd.c b/mpd.c
deleted file mode 100644
index d48bcdb..0000000
--- a/mpd.c
+++ /dev/null
@@ -1,649 +0,0 @@
-// Copied from desktop-tools, should go to liberty if it proves useful
-// XXX: changed: added a debugging callback instead of hardcoded print_debug
-
-// --- MPD client interface ----------------------------------------------------
-
-// This is a rather thin MPD client interface intended for basic tasks
-
-#define MPD_SUBSYSTEM_TABLE(XX)                 \
-	XX (DATABASE,         0, "database")        \
-	XX (UPDATE,           1, "update")          \
-	XX (STORED_PLAYLIST,  2, "stored_playlist") \
-	XX (PLAYLIST,         3, "playlist")        \
-	XX (PLAYER,           4, "player")          \
-	XX (MIXER,            5, "mixer")           \
-	XX (OUTPUT,           6, "output")          \
-	XX (OPTIONS,          7, "options")         \
-	XX (STICKER,          8, "sticker")         \
-	XX (SUBSCRIPTION,     9, "subscription")    \
-	XX (MESSAGE,         10, "message")
-
-enum mpd_subsystem
-{
-#define XX(a, b, c) MPD_SUBSYSTEM_ ## a = (1 << b),
-	MPD_SUBSYSTEM_TABLE (XX)
-#undef XX
-	MPD_SUBSYSTEM_MAX
-};
-
-static const char *mpd_subsystem_names[] =
-{
-#define XX(a, b, c) [b] = c,
-	MPD_SUBSYSTEM_TABLE (XX)
-#undef XX
-};
-
-// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
-
-enum mpd_client_state
-{
-	MPD_DISCONNECTED,                   ///< Not connected
-	MPD_CONNECTING,                     ///< Currently connecting
-	MPD_CONNECTED                       ///< Connected
-};
-
-struct mpd_response
-{
-	bool success;                       ///< OK or ACK
-
-	// ACK-only fields:
-
-	int error;                          ///< Numeric error value (ack.h)
-	int list_offset;                    ///< Offset of command in list
-	char *current_command;              ///< Name of the erroring command
-	char *message_text;                 ///< Error message
-};
-
-/// Task completion callback
-typedef void (*mpd_client_task_cb) (const struct mpd_response *response,
-	const struct str_vector *data, void *user_data);
-
-struct mpd_client_task
-{
-	LIST_HEADER (struct mpd_client_task)
-
-	mpd_client_task_cb callback;        ///< Callback on completion
-	void *user_data;                    ///< User data
-};
-
-struct mpd_client
-{
-	struct poller *poller;              ///< Poller
-
-	// Connection:
-
-	enum mpd_client_state state;        ///< Connection state
-	struct connector *connector;        ///< Connection establisher
-
-	int socket;                         ///< MPD socket
-	struct str read_buffer;             ///< Input yet to be processed
-	struct str write_buffer;            ///< Outut yet to be be sent out
-	struct poller_fd socket_event;      ///< We can read from the socket
-
-	struct poller_timer timeout_timer;  ///< Connection seems to be dead
-
-	// Protocol:
-
-	bool got_hello;                     ///< Got the OK MPD hello message
-
-	bool idling;                        ///< Sent idle as the last command
-	unsigned idling_subsystems;         ///< Subsystems we're idling for
-	bool in_list;                       ///< We're inside a command list
-
-	struct mpd_client_task *tasks;      ///< Task queue
-	struct mpd_client_task *tasks_tail; ///< Tail of task queue
-	struct str_vector data;             ///< Data from last command
-
-	// User configuration:
-
-	void *user_data;                    ///< User data for callbacks
-
-	/// Callback after connection has been successfully established
-	void (*on_connected) (void *user_data);
-
-	/// Callback for general failures or even normal disconnection;
-	/// the interface is reinitialized
-	void (*on_failure) (void *user_data);
-
-	/// Callback to receive "idle" updates.
-	/// Remember to restart the idle if needed.
-	void (*on_event) (unsigned subsystems, void *user_data);
-
-	/// Callback to trace protocol I/O
-	void (*on_io_hook) (void *user_data, bool outgoing, const char *line);
-};
-
-static void mpd_client_reset (struct mpd_client *self);
-static void mpd_client_destroy_connector (struct mpd_client *self);
-
-static void
-mpd_client_init (struct mpd_client *self, struct poller *poller)
-{
-	memset (self, 0, sizeof *self);
-
-	self->poller = poller;
-	self->socket = -1;
-
-	str_init (&self->read_buffer);
-	str_init (&self->write_buffer);
-
-	str_vector_init (&self->data);
-
-	poller_fd_init (&self->socket_event, poller, -1);
-	poller_timer_init (&self->timeout_timer, poller);
-}
-
-static void
-mpd_client_free (struct mpd_client *self)
-{
-	// So that we don't have to repeat most of the stuff
-	mpd_client_reset (self);
-
-	str_free (&self->read_buffer);
-	str_free (&self->write_buffer);
-
-	str_vector_free (&self->data);
-}
-
-// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
-
-/// Reinitialize the interface so that you can reconnect anew
-static void
-mpd_client_reset (struct mpd_client *self)
-{
-	if (self->state == MPD_CONNECTING)
-		mpd_client_destroy_connector (self);
-
-	if (self->socket != -1)
-		xclose (self->socket);
-	self->socket = -1;
-
-	self->socket_event.closed = true;
-	poller_fd_reset (&self->socket_event);
-	poller_timer_reset (&self->timeout_timer);
-
-	str_reset (&self->read_buffer);
-	str_reset (&self->write_buffer);
-
-	str_vector_reset (&self->data);
-
-	self->got_hello = false;
-	self->idling = false;
-	self->idling_subsystems = 0;
-	self->in_list = false;
-
-	LIST_FOR_EACH (struct mpd_client_task, iter, self->tasks)
-		free (iter);
-	self->tasks = self->tasks_tail = NULL;
-
-	self->state = MPD_DISCONNECTED;
-}
-
-static void
-mpd_client_fail (struct mpd_client *self)
-{
-	mpd_client_reset (self);
-	if (self->on_failure)
-		self->on_failure (self->user_data);
-}
-
-// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
-
-static bool
-mpd_client_parse_response (const char *p, struct mpd_response *response)
-{
-	if (!strcmp (p, "OK"))
-		return response->success = true;
-	if (!strcmp (p, "list_OK"))
-		// TODO: either implement this or fail the connection properly
-		hard_assert (!"command_list_ok_begin not implemented");
-
-	char *end = NULL;
-	if (*p++ != 'A' || *p++ != 'C' || *p++ != 'K' || *p++ != ' ' || *p++ != '[')
-		return false;
-
-	errno = 0;
-	response->error = strtoul (p, &end, 10);
-	if (errno != 0 || end == p)
-		return false;
-	p = end;
-	if (*p++ != '@')
-		return false;
-
-	errno = 0;
-	response->list_offset = strtoul (p, &end, 10);
-	if (errno != 0 || end == p)
-		return false;
-	p = end;
-	if (*p++ != ']' || *p++ != ' ' || *p++ != '{' || !(end = strchr (p, '}')))
-		return false;
-
-	response->current_command = xstrndup (p, end - p);
-	p = end + 1;
-
-	if (*p++ != ' ')
-		return false;
-
-	response->message_text = xstrdup (p);
-	response->success = false;
-	return true;
-}
-
-static void
-mpd_client_dispatch (struct mpd_client *self, struct mpd_response *response)
-{
-	struct mpd_client_task *task;
-	if (!(task = self->tasks))
-		return;
-
-	if (task->callback)
-		task->callback (response, &self->data, task->user_data);
-	str_vector_reset (&self->data);
-
-	LIST_UNLINK_WITH_TAIL (self->tasks, self->tasks_tail, task);
-	free (task);
-}
-
-static bool
-mpd_client_parse_hello (struct mpd_client *self, const char *line)
-{
-	const char hello[] = "OK MPD ";
-	if (strncmp (line, hello, sizeof hello - 1))
-	{
-		print_debug ("invalid MPD hello message");
-		return false;
-	}
-
-	// TODO: call "on_connected" now.  We should however also set up a timer
-	//   so that we don't wait on this message forever.
-	return self->got_hello = true;
-}
-
-static bool
-mpd_client_parse_line (struct mpd_client *self, const char *line)
-{
-	if (self->on_io_hook)
-		self->on_io_hook (self->user_data, false, line);
-
-	if (!self->got_hello)
-		return mpd_client_parse_hello (self, line);
-
-	struct mpd_response response;
-	memset (&response, 0, sizeof response);
-	if (mpd_client_parse_response (line, &response))
-	{
-		mpd_client_dispatch (self, &response);
-		free (response.current_command);
-		free (response.message_text);
-	}
-	else
-		str_vector_add (&self->data, line);
-	return true;
-}
-
-/// All output from MPD commands seems to be in a trivial "key: value" format
-static char *
-mpd_client_parse_kv (char *line, char **value)
-{
-	char *sep;
-	if (!(sep = strstr (line, ": ")))
-		return NULL;
-
-	*sep = 0;
-	*value = sep + 2;
-	return line;
-}
-
-// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
-
-static void
-mpd_client_update_poller (struct mpd_client *self)
-{
-	poller_fd_set (&self->socket_event,
-		self->write_buffer.len ? (POLLIN | POLLOUT) : POLLIN);
-}
-
-static bool
-mpd_client_process_input (struct mpd_client *self)
-{
-	// Split socket input at newlines and process them separately
-	struct str *rb = &self->read_buffer;
-	char *start = rb->str, *end = start + rb->len;
-	for (char *p = start; p < end; p++)
-	{
-		if (*p != '\n')
-			continue;
-
-		*p = 0;
-		if (!mpd_client_parse_line (self, start))
-			return false;
-		start = p + 1;
-	}
-
-	str_remove_slice (rb, 0, start - rb->str);
-	return true;
-}
-
-static void
-mpd_client_on_ready (const struct pollfd *pfd, void *user_data)
-{
-	(void) pfd;
-
-	struct mpd_client *self = user_data;
-	if (socket_io_try_read  (self->socket, &self->read_buffer)  != SOCKET_IO_OK
-	 || !mpd_client_process_input (self)
-	 || socket_io_try_write (self->socket, &self->write_buffer) != SOCKET_IO_OK)
-		mpd_client_fail (self);
-	else
-		mpd_client_update_poller (self);
-}
-
-// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
-
-static bool
-mpd_client_must_quote_char (char c)
-{
-	return (unsigned char) c <= ' ' || c == '"' || c == '\'';
-}
-
-static bool
-mpd_client_must_quote (const char *s)
-{
-	if (!*s)
-		return true;
-	for (; *s; s++)
-		if (mpd_client_must_quote_char (*s))
-			return true;
-	return false;
-}
-
-static void
-mpd_client_quote (const char *s, struct str *output)
-{
-	str_append_c (output, '"');
-	for (; *s; s++)
-	{
-		if (mpd_client_must_quote_char (*s))
-			str_append_c (output, '\\');
-		str_append_c (output, *s);
-	}
-	str_append_c (output, '"');
-}
-
-/// Beware that delivery of the event isn't deferred and you musn't make
-/// changes to the interface while processing the event!
-static void
-mpd_client_add_task
-	(struct mpd_client *self, mpd_client_task_cb cb, void *user_data)
-{
-	// This only has meaning with command_list_ok_begin, and then it requires
-	// special handling (all in-list tasks need to be specially marked and
-	// later flushed if an early ACK or OK arrives).
-	hard_assert (!self->in_list);
-
-	struct mpd_client_task *task = xcalloc (1, sizeof *self);
-	task->callback = cb;
-	task->user_data = user_data;
-	LIST_APPEND_WITH_TAIL (self->tasks, self->tasks_tail, task);
-}
-
-/// Send a command.  Remember to call mpd_client_add_task() to handle responses,
-/// unless the command is being sent in a list.
-static void mpd_client_send_command
-	(struct mpd_client *self, const char *command, ...) ATTRIBUTE_SENTINEL;
-
-static void
-mpd_client_send_commandv (struct mpd_client *self, char **commands)
-{
-	// Automatically interrupt idle mode
-	if (self->idling)
-	{
-		poller_timer_reset (&self->timeout_timer);
-
-		self->idling = false;
-		self->idling_subsystems = 0;
-		mpd_client_send_command (self, "noidle", NULL);
-	}
-
-	struct str line;
-	str_init (&line);
-
-	for (; *commands; commands++)
-	{
-		if (line.len)
-			str_append_c (&line, ' ');
-
-		if (mpd_client_must_quote (*commands))
-			mpd_client_quote (*commands, &line);
-		else
-			str_append (&line, *commands);
-	}
-
-	if (self->on_io_hook)
-		self->on_io_hook (self->user_data, true, line.str);
-
-	str_append_c (&line, '\n');
-	str_append_str (&self->write_buffer, &line);
-	str_free (&line);
-
-	mpd_client_update_poller (self);
-}
-
-static void
-mpd_client_send_command (struct mpd_client *self, const char *command, ...)
-{
-	struct str_vector v;
-	str_vector_init (&v);
-
-	va_list ap;
-	va_start (ap, command);
-	for (; command; command = va_arg (ap, const char *))
-		str_vector_add (&v, command);
-	va_end (ap);
-
-	mpd_client_send_commandv (self, v.vector);
-	str_vector_free (&v);
-}
-
-// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
-
-static void
-mpd_client_list_begin (struct mpd_client *self)
-{
-	hard_assert (!self->in_list);
-	mpd_client_send_command (self, "command_list_begin", NULL);
-	self->in_list = true;
-}
-
-/// End a list of commands.  Remember to call mpd_client_add_task()
-/// to handle the summary response.
-static void
-mpd_client_list_end (struct mpd_client *self)
-{
-	hard_assert (self->in_list);
-	mpd_client_send_command (self, "command_list_end", NULL);
-	self->in_list = false;
-}
-
-// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
-
-static bool
-mpd_resolve_subsystem (const char *name, unsigned *output)
-{
-	for (size_t i = 0; i < N_ELEMENTS (mpd_subsystem_names); i++)
-		if (!strcasecmp_ascii (name, mpd_subsystem_names[i]))
-		{
-			*output |= 1 << i;
-			return true;
-		}
-	return false;
-}
-
-static void
-mpd_client_on_idle_return (const struct mpd_response *response,
-	const struct str_vector *data, void *user_data)
-{
-	(void) response;
-
-	struct mpd_client *self = user_data;
-	unsigned subsystems = 0;
-	for (size_t i = 0; i < data->len; i++)
-	{
-		char *value, *key;
-		if (!(key = mpd_client_parse_kv (data->vector[i], &value)))
-			print_debug ("%s: %s", "erroneous MPD output", data->vector[i]);
-		else if (strcasecmp_ascii (key, "changed"))
-			print_debug ("%s: %s", "unexpected idle key", key);
-		else if (!mpd_resolve_subsystem (value, &subsystems))
-			print_debug ("%s: %s", "unknown subsystem", value);
-	}
-
-	// Not resetting "idling" here, we may send an extra "noidle" no problem
-	if (self->on_event && subsystems)
-		self->on_event (subsystems, self->user_data);
-}
-
-static void mpd_client_idle (struct mpd_client *self, unsigned subsystems);
-
-static void
-mpd_client_on_timeout (void *user_data)
-{
-	struct mpd_client *self = user_data;
-
-	// Abort and immediately restore the current idle so that MPD doesn't
-	// disconnect us, even though the documentation says this won't happen.
-	// Just sending this out should bring a dead connection down over TCP.
-	// TODO: set another timer to make sure we get a reply
-	mpd_client_idle (self, self->idling_subsystems);
-}
-
-/// When not expecting to send any further commands, you should call this
-/// in order to keep the connection alive.  Or to receive updates.
-static void
-mpd_client_idle (struct mpd_client *self, unsigned subsystems)
-{
-	hard_assert (!self->in_list);
-
-	struct str_vector v;
-	str_vector_init (&v);
-
-	str_vector_add (&v, "idle");
-	for (size_t i = 0; i < N_ELEMENTS (mpd_subsystem_names); i++)
-		if (subsystems & (1 << i))
-			str_vector_add (&v, mpd_subsystem_names[i]);
-
-	mpd_client_send_commandv (self, v.vector);
-	str_vector_free (&v);
-
-	self->timeout_timer.dispatcher = mpd_client_on_timeout;
-	self->timeout_timer.user_data = self;
-	poller_timer_set (&self->timeout_timer, 5 * 60 * 1000);
-
-	mpd_client_add_task (self, mpd_client_on_idle_return, self);
-	self->idling = true;
-	self->idling_subsystems = subsystems;
-}
-
-// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
-
-static void
-mpd_client_finish_connection (struct mpd_client *self, int socket)
-{
-	set_blocking (socket, false);
-	self->socket = socket;
-	self->state = MPD_CONNECTED;
-
-	poller_fd_init (&self->socket_event, self->poller, self->socket);
-	self->socket_event.dispatcher = mpd_client_on_ready;
-	self->socket_event.user_data = self;
-
-	mpd_client_update_poller (self);
-
-	if (self->on_connected)
-		self->on_connected (self->user_data);
-}
-
-static void
-mpd_client_destroy_connector (struct mpd_client *self)
-{
-	if (self->connector)
-		connector_free (self->connector);
-	free (self->connector);
-	self->connector = NULL;
-
-	// Not connecting anymore
-	self->state = MPD_DISCONNECTED;
-}
-
-static void
-mpd_client_on_connector_failure (void *user_data)
-{
-	struct mpd_client *self = user_data;
-	mpd_client_destroy_connector (self);
-	mpd_client_fail (self);
-}
-
-static void
-mpd_client_on_connector_connected
-	(void *user_data, int socket, const char *host)
-{
-	(void) host;
-
-	struct mpd_client *self = user_data;
-	mpd_client_destroy_connector (self);
-	mpd_client_finish_connection (self, socket);
-}
-
-static bool
-mpd_client_connect_unix (struct mpd_client *self, const char *address,
-	struct error **e)
-{
-	int fd = socket (AF_UNIX, SOCK_STREAM, 0);
-	if (fd == -1)
-	{
-		error_set (e, "%s: %s", "socket", strerror (errno));
-		return false;
-	}
-
-	// Expand tilde if needed
-	char *expanded = resolve_filename (address, xstrdup);
-
-	struct sockaddr_un sun;
-	sun.sun_family = AF_UNIX;
-	strncpy (sun.sun_path, expanded, sizeof sun.sun_path);
-	sun.sun_path[sizeof sun.sun_path - 1] = 0;
-
-	free (expanded);
-
-	if (connect (fd, (struct sockaddr *) &sun, sizeof sun))
-	{
-		error_set (e, "%s: %s", "connect", strerror (errno));
-		return false;
-	}
-
-	mpd_client_finish_connection (self, fd);
-	return true;
-}
-
-static bool
-mpd_client_connect (struct mpd_client *self, const char *address,
-	const char *service, struct error **e)
-{
-	hard_assert (self->state == MPD_DISCONNECTED);
-
-	// If it looks like a path, assume it's a UNIX socket
-	if (strchr (address, '/'))
-		return mpd_client_connect_unix (self, address, e);
-
-	struct connector *connector = xmalloc (sizeof *connector);
-	connector_init (connector, self->poller);
-	self->connector = connector;
-
-	connector->user_data    = self;
-	connector->on_connected = mpd_client_on_connector_connected;
-	connector->on_failure   = mpd_client_on_connector_failure;
-
-	connector_add_target (connector, address, service);
-	self->state = MPD_CONNECTING;
-	return true;
-}
diff --git a/nncmpp.c b/nncmpp.c
index e5e98a4..c2090c3 100644
--- a/nncmpp.c
+++ b/nncmpp.c
@@ -62,11 +62,9 @@ enum
 #define LIBERTY_WANT_POLLER
 #define LIBERTY_WANT_ASYNC
 #define LIBERTY_WANT_PROTO_HTTP
+#define LIBERTY_WANT_PROTO_MPD
 #include "liberty/liberty.c"
 
-#include <sys/un.h>
-#include "mpd.c"
-
 #include <locale.h>
 #include <termios.h>
 #ifndef TIOCGWINSZ
@@ -2395,9 +2393,6 @@ debug_tab_init (void)
 
 // --- MPD interface -----------------------------------------------------------
 
-// TODO: this entire thing has been slavishly copy-pasted from dwmstatus
-// TODO: try to move some of this code to mpd.c
-
 static void
 mpd_update_playback_state (void)
 {