output/httpd: move to dedicated directory

src/output/plugins/httpd/HttpdInternal.hxx

@@ -0,0 +1,273 @@
+/*
+ * Copyright (C) 2003-2014 The Music Player Daemon Project
+ * http://www.musicpd.org
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ */
+
+/** \file
+ *
+ * Internal declarations for the "httpd" audio output plugin.
+ */
+
+#ifndef MPD_OUTPUT_HTTPD_INTERNAL_H
+#define MPD_OUTPUT_HTTPD_INTERNAL_H
+
+#include "output/Internal.hxx"
+#include "output/Timer.hxx"
+#include "thread/Mutex.hxx"
+#include "event/ServerSocket.hxx"
+#include "event/DeferredMonitor.hxx"
+#include "util/Cast.hxx"
+
+#ifdef _LIBCPP_VERSION
+/* can't use incomplete template arguments with libc++ */
+#include "HttpdClient.hxx"
+#endif
+
+#include <forward_list>
+#include <queue>
+#include <list>
+
+struct config_param;
+class Error;
+class EventLoop;
+class ServerSocket;
+class HttpdClient;
+class Page;
+struct Encoder;
+struct Tag;
+
+class HttpdOutput final : ServerSocket, DeferredMonitor {
+	AudioOutput base;
+
+	/**
+	 * True if the audio output is open and accepts client
+	 * connections.
+	 */
+	bool open;
+
+	/**
+	 * The configured encoder plugin.
+	 */
+	Encoder *encoder;
+
+	/**
+	 * Number of bytes which were fed into the encoder, without
+	 * ever receiving new output.  This is used to estimate
+	 * whether MPD should manually flush the encoder, to avoid
+	 * buffer underruns in the client.
+	 */
+	size_t unflushed_input;
+
+public:
+	/**
+	 * The MIME type produced by the #encoder.
+	 */
+	const char *content_type;
+
+	/**
+	 * This mutex protects the listener socket and the client
+	 * list.
+	 */
+	mutable Mutex mutex;
+
+	/**
+	 * This condition gets signalled when an item is removed from
+	 * #pages.
+	 */
+	Cond cond;
+
+private:
+	/**
+	 * A #Timer object to synchronize this output with the
+	 * wallclock.
+	 */
+	Timer *timer;
+
+	/**
+	 * The header page, which is sent to every client on connect.
+	 */
+	Page *header;
+
+	/**
+	 * The metadata, which is sent to every client.
+	 */
+	Page *metadata;
+
+	/**
+	 * The page queue, i.e. pages from the encoder to be
+	 * broadcasted to all clients.  This container is necessary to
+	 * pass pages from the OutputThread to the IOThread.  It is
+	 * protected by #mutex, and removing signals #cond.
+	 */
+	std::queue<Page *, std::list<Page *>> pages;
+
+ public:
+	/**
+	 * The configured name.
+	 */
+	char const *name;
+	/**
+	 * The configured genre.
+	 */
+	char const *genre;
+	/**
+	 * The configured website address.
+	 */
+	char const *website;
+
+private:
+	/**
+	 * A linked list containing all clients which are currently
+	 * connected.
+	 */
+	std::forward_list<HttpdClient> clients;
+
+	/**
+	 * A temporary buffer for the httpd_output_read_page()
+	 * function.
+	 */
+	char buffer[32768];
+
+	/**
+	 * The maximum and current number of clients connected
+	 * at the same time.
+	 */
+	unsigned clients_max, clients_cnt;
+
+public:
+	HttpdOutput(EventLoop &_loop);
+	~HttpdOutput();
+
+#if GCC_CHECK_VERSION(4,6) || defined(__clang__)
+#pragma GCC diagnostic push
+#pragma GCC diagnostic ignored "-Winvalid-offsetof"
+#endif
+
+	static constexpr HttpdOutput *Cast(AudioOutput *ao) {
+		return ContainerCast(ao, HttpdOutput, base);
+	}
+
+#if GCC_CHECK_VERSION(4,6) || defined(__clang__)
+#pragma GCC diagnostic pop
+#endif
+
+	using DeferredMonitor::GetEventLoop;
+
+	bool Init(const config_param &param, Error &error);
+
+	bool Configure(const config_param &param, Error &error);
+
+	AudioOutput *InitAndConfigure(const config_param &param,
+				       Error &error) {
+		if (!Init(param, error))
+			return nullptr;
+
+		if (!Configure(param, error))
+			return nullptr;
+
+		return &base;
+	}
+
+	bool Bind(Error &error);
+	void Unbind();
+
+	/**
+	 * Caller must lock the mutex.
+	 */
+	bool OpenEncoder(AudioFormat &audio_format, Error &error);
+
+	/**
+	 * Caller must lock the mutex.
+	 */
+	bool Open(AudioFormat &audio_format, Error &error);
+
+	/**
+	 * Caller must lock the mutex.
+	 */
+	void Close();
+
+	/**
+	 * Check whether there is at least one client.
+	 *
+	 * Caller must lock the mutex.
+	 */
+	gcc_pure
+	bool HasClients() const {
+		return !clients.empty();
+	}
+
+	/**
+	 * Check whether there is at least one client.
+	 */
+	gcc_pure
+	bool LockHasClients() const {
+		const ScopeLock protect(mutex);
+		return HasClients();
+	}
+
+	void AddClient(int fd);
+
+	/**
+	 * Removes a client from the httpd_output.clients linked list.
+	 */
+	void RemoveClient(HttpdClient &client);
+
+	/**
+	 * Sends the encoder header to the client.  This is called
+	 * right after the response headers have been sent.
+	 */
+	void SendHeader(HttpdClient &client) const;
+
+	gcc_pure
+	unsigned Delay() const;
+
+	/**
+	 * Reads data from the encoder (as much as available) and
+	 * returns it as a new #page object.
+	 */
+	Page *ReadPage();
+
+	/**
+	 * Broadcasts a page struct to all clients.
+	 *
+	 * Mutext must not be locked.
+	 */
+	void BroadcastPage(Page *page);
+
+	/**
+	 * Broadcasts data from the encoder to all clients.
+	 */
+	void BroadcastFromEncoder();
+
+	bool EncodeAndPlay(const void *chunk, size_t size, Error &error);
+
+	void SendTag(const Tag *tag);
+
+	size_t Play(const void *chunk, size_t size, Error &error);
+
+	void CancelAllClients();
+
+private:
+	virtual void RunDeferred() override;
+
+	virtual void OnAccept(int fd, const sockaddr &address,
+			      size_t address_length, int uid) override;
+};
+
+extern const class Domain httpd_output_domain;
+
+#endif