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-rw-r--r--mpd.c649
1 files changed, 0 insertions, 649 deletions
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;
-}