output/httpd: convert to C++

src/output/HttpdClient.cxx

@@ -0,0 +1,592 @@
+/*
+ * Copyright (C) 2003-2011 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.
+ */
+
+#include "config.h"
+#include "HttpdClient.hxx"
+#include "HttpdInternal.hxx"
+#include "util/fifo_buffer.h"
+#include "page.h"
+#include "icy_server.h"
+#include "glib_socket.h"
+
+#include <assert.h>
+#include <string.h>
+
+#undef G_LOG_DOMAIN
+#define G_LOG_DOMAIN "httpd_output"
+
+HttpdClient::~HttpdClient()
+{
+	if (state == RESPONSE) {
+		if (write_source_id != 0)
+			g_source_remove(write_source_id);
+
+		if (current_page != nullptr)
+			page_unref(current_page);
+
+		for (auto page : pages)
+			page_unref(page);
+	} else
+		fifo_buffer_free(input);
+
+	if (metadata)
+		page_unref(metadata);
+
+	g_source_remove(read_source_id);
+	g_io_channel_unref(channel);
+}
+
+void
+HttpdClient::Close()
+{
+	httpd_output_remove_client(httpd, this);
+}
+
+void
+HttpdClient::LockClose()
+{
+	const ScopeLock protect(httpd->mutex);
+	Close();
+}
+
+void
+HttpdClient::BeginResponse()
+{
+	assert(state != RESPONSE);
+
+	state = RESPONSE;
+	write_source_id = 0;
+	current_page = nullptr;
+
+	httpd_output_send_header(httpd, this);
+}
+
+/**
+ * Handle a line of the HTTP request.
+ */
+bool
+HttpdClient::HandleLine(const char *line)
+{
+	assert(state != RESPONSE);
+
+	if (state == REQUEST) {
+		if (strncmp(line, "GET /", 5) != 0) {
+			/* only GET is supported */
+			g_warning("malformed request line from client");
+			return false;
+		}
+
+		line = strchr(line + 5, ' ');
+		if (line == nullptr || strncmp(line + 1, "HTTP/", 5) != 0) {
+			/* HTTP/0.9 without request headers */
+			BeginResponse();
+			return true;
+		}
+
+		/* after the request line, request headers follow */
+		state = HEADERS;
+		return true;
+	} else {
+		if (*line == 0) {
+			/* empty line: request is finished */
+			BeginResponse();
+			return true;
+		}
+
+		if (g_ascii_strncasecmp(line, "Icy-MetaData: 1", 15) == 0) {
+			/* Send icy metadata */
+			metadata_requested = metadata_supported;
+			return true;
+		}
+
+		if (g_ascii_strncasecmp(line, "transferMode.dlna.org: Streaming", 32) == 0) {
+			/* Send as dlna */
+			dlna_streaming_requested = true;
+			/* metadata is not supported by dlna streaming, so disable it */
+			metadata_supported = false;
+			metadata_requested = false;
+			return true;
+		}
+
+		/* expect more request headers */
+		return true;
+	}
+}
+
+char *
+HttpdClient::ReadLine()
+{
+	assert(state != RESPONSE);
+
+	const ScopeLock protect(httpd->mutex);
+
+	size_t length;
+	const char *p = (const char *)fifo_buffer_read(input, &length);
+	if (p == nullptr)
+		/* empty input buffer */
+		return nullptr;
+
+	const char *newline = (const char *)memchr(p, '\n', length);
+	if (newline == nullptr)
+		/* incomplete line */
+		return nullptr;
+
+	char *line = g_strndup(p, newline - p);
+	fifo_buffer_consume(input, newline - p + 1);
+
+	/* remove trailing whitespace (e.g. '\r') */
+	return g_strchomp(line);
+}
+
+/**
+ * Sends the status line and response headers to the client.
+ */
+bool
+HttpdClient::SendResponse()
+{
+	char buffer[1024];
+	GError *error = nullptr;
+	GIOStatus status;
+	gsize bytes_written;
+
+	assert(state == RESPONSE);
+
+	if (dlna_streaming_requested) {
+		g_snprintf(buffer, sizeof(buffer),
+			   "HTTP/1.1 206 OK\r\n"
+			   "Content-Type: %s\r\n"
+			   "Content-Length: 10000\r\n"
+			   "Content-RangeX: 0-1000000/1000000\r\n"
+			   "transferMode.dlna.org: Streaming\r\n"
+			   "Accept-Ranges: bytes\r\n"
+			   "Connection: close\r\n"
+			   "realTimeInfo.dlna.org: DLNA.ORG_TLAG=*\r\n"
+			   "contentFeatures.dlna.org: DLNA.ORG_OP=01;DLNA.ORG_CI=0\r\n"
+			   "\r\n",
+			   httpd->content_type);
+
+	} else if (metadata_requested) {
+		gchar *metadata_header;
+
+		metadata_header =
+			icy_server_metadata_header(httpd->name, httpd->genre,
+						   httpd->website,
+						   httpd->content_type,
+						   metaint);
+
+		g_strlcpy(buffer, metadata_header, sizeof(buffer));
+
+		g_free(metadata_header);
+
+       } else { /* revert to a normal HTTP request */
+		g_snprintf(buffer, sizeof(buffer),
+			   "HTTP/1.1 200 OK\r\n"
+			   "Content-Type: %s\r\n"
+			   "Connection: close\r\n"
+			   "Pragma: no-cache\r\n"
+			   "Cache-Control: no-cache, no-store\r\n"
+			   "\r\n",
+			   httpd->content_type);
+	}
+
+	status = g_io_channel_write_chars(channel,
+					  buffer, strlen(buffer),
+					  &bytes_written, &error);
+
+	switch (status) {
+	case G_IO_STATUS_NORMAL:
+	case G_IO_STATUS_AGAIN:
+		return true;
+
+	case G_IO_STATUS_EOF:
+		/* client has disconnected */
+
+		Close();
+		return false;
+
+	case G_IO_STATUS_ERROR:
+		/* I/O error */
+
+		g_warning("failed to write to client: %s", error->message);
+		g_error_free(error);
+
+		Close();
+		return false;
+	}
+
+	/* unreachable */
+	Close();
+	return false;
+}
+
+bool
+HttpdClient::Received()
+{
+	assert(state != RESPONSE);
+
+	char *line;
+	bool success;
+
+	while ((line = ReadLine()) != nullptr) {
+		success = HandleLine(line);
+		g_free(line);
+		if (!success) {
+			assert(state != RESPONSE);
+			return false;
+		}
+
+		if (state == RESPONSE) {
+			if (!fifo_buffer_is_empty(input)) {
+				g_warning("unexpected input from client");
+				return false;
+			}
+
+			fifo_buffer_free(input);
+
+			return SendResponse();
+		}
+	}
+
+	return true;
+}
+
+bool
+HttpdClient::Read()
+{
+	size_t max_length;
+	GError *error = nullptr;
+	GIOStatus status;
+	gsize bytes_read;
+
+	if (state == RESPONSE) {
+		/* the client has already sent the request, and he
+		   must not send more */
+		char buffer[1];
+
+		status = g_io_channel_read_chars(channel, buffer,
+						 sizeof(buffer), &bytes_read,
+						 nullptr);
+		if (status == G_IO_STATUS_NORMAL)
+			g_warning("unexpected input from client");
+
+		return false;
+	}
+
+	char *p = (char *)fifo_buffer_write(input, &max_length);
+	if (p == nullptr) {
+		g_warning("buffer overflow");
+		return false;
+	}
+
+	status = g_io_channel_read_chars(channel, p, max_length,
+					 &bytes_read, &error);
+	switch (status) {
+	case G_IO_STATUS_NORMAL:
+		fifo_buffer_append(input, bytes_read);
+		return Received();
+
+	case G_IO_STATUS_AGAIN:
+		/* try again later, after select() */
+		return true;
+
+	case G_IO_STATUS_EOF:
+		/* peer disconnected */
+		return false;
+
+	case G_IO_STATUS_ERROR:
+		/* I/O error */
+		g_warning("failed to read from client: %s",
+			  error->message);
+		g_error_free(error);
+		return false;
+	}
+
+	/* unreachable */
+	return false;
+}
+
+static gboolean
+httpd_client_in_event(G_GNUC_UNUSED GIOChannel *source, GIOCondition condition,
+		      gpointer data)
+{
+	HttpdClient *client = (HttpdClient *)data;
+
+	if (condition == G_IO_IN && client->Read()) {
+		return true;
+	} else {
+		client->LockClose();
+		return false;
+	}
+}
+
+HttpdClient::HttpdClient(httpd_output *_httpd, int _fd,
+			 bool _metadata_supported)
+	:httpd(_httpd),
+	 channel(g_io_channel_new_socket(_fd)),
+	 input(fifo_buffer_new(4096)),
+	 state(REQUEST),
+	 dlna_streaming_requested(false),
+	 metadata_supported(_metadata_supported),
+	 metadata_requested(false), metadata_sent(true),
+	 metaint(8192), /*TODO: just a std value */
+	 metadata(nullptr),
+	 metadata_current_position(0), metadata_fill(0)
+{
+	/* GLib is responsible for closing the file descriptor */
+	g_io_channel_set_close_on_unref(channel, true);
+	/* NULL encoding means the stream is binary safe */
+	g_io_channel_set_encoding(channel, nullptr, nullptr);
+	/* we prefer to do buffering */
+	g_io_channel_set_buffered(channel, false);
+
+	read_source_id = g_io_add_watch(channel,
+					GIOCondition(G_IO_IN|G_IO_ERR|G_IO_HUP),
+					httpd_client_in_event, this);
+}
+
+size_t
+HttpdClient::GetQueueSize() const
+{
+	if (state != RESPONSE)
+		return 0;
+
+	size_t size = 0;
+	for (auto page : pages)
+		size += page->size;
+	return size;
+}
+
+void
+HttpdClient::CancelQueue()
+{
+	if (state != RESPONSE)
+		return;
+
+	for (auto page : pages)
+		page_unref(page);
+	pages.clear();
+
+	if (write_source_id != 0 && current_page == nullptr) {
+		g_source_remove(write_source_id);
+		write_source_id = 0;
+	}
+}
+
+static GIOStatus
+write_page_to_channel(GIOChannel *channel,
+		      const struct page *page, size_t position,
+		      gsize *bytes_written_r, GError **error)
+{
+	assert(channel != nullptr);
+	assert(page != nullptr);
+	assert(position < page->size);
+
+	return g_io_channel_write_chars(channel,
+					(const gchar*)page->data + position,
+					page->size - position,
+					bytes_written_r, error);
+}
+
+static GIOStatus
+write_n_bytes_to_channel(GIOChannel *channel, const struct page *page,
+			 size_t position, gint n,
+			 gsize *bytes_written_r, GError **error)
+{
+	GIOStatus status;
+
+	assert(channel != nullptr);
+	assert(page != nullptr);
+	assert(position < page->size);
+
+	if (n == -1) {
+		status =  write_page_to_channel (channel, page, position,
+						 bytes_written_r, error);
+	} else {
+		status = g_io_channel_write_chars(channel,
+						  (const gchar*)page->data + position,
+						  n, bytes_written_r, error);
+	}
+
+	return status;
+}
+
+int
+HttpdClient::GetBytesTillMetaData() const
+{
+	if (metadata_requested &&
+	    current_page->size - current_position > metaint - metadata_fill)
+		return metaint - metadata_fill;
+
+	return -1;
+}
+
+inline bool
+HttpdClient::Write()
+{
+	GError *error = nullptr;
+	GIOStatus status;
+	gsize bytes_written;
+
+	const ScopeLock protect(httpd->mutex);
+
+	assert(state == RESPONSE);
+
+	if (write_source_id == 0)
+		/* another thread has removed the event source while
+		   this thread was waiting for httpd->mutex */
+		return false;
+
+	if (current_page == nullptr) {
+		current_page = pages.front();
+		pages.pop_front();
+		current_position = 0;
+	}
+
+	const gint bytes_to_write = GetBytesTillMetaData();
+	if (bytes_to_write == 0) {
+		gint metadata_to_write;
+
+		metadata_to_write = metadata_current_position;
+
+		if (!metadata_sent) {
+			status = write_page_to_channel(channel,
+						       metadata,
+						       metadata_to_write,
+						       &bytes_written, &error);
+
+			metadata_current_position += bytes_written;
+
+			if (metadata->size - metadata_current_position == 0) {
+				metadata_fill = 0;
+				metadata_current_position = 0;
+				metadata_sent = true;
+			}
+		} else {
+			struct page *empty_meta;
+			guchar empty_data = 0;
+
+			empty_meta = page_new_copy(&empty_data, 1);
+
+			status = write_page_to_channel(channel,
+						       empty_meta,
+						       metadata_to_write,
+						       &bytes_written, &error);
+
+			metadata_current_position += bytes_written;
+
+			if (empty_meta->size - metadata_current_position == 0) {
+				metadata_fill = 0;
+				metadata_current_position = 0;
+			}
+		}
+
+		bytes_written = 0;
+	} else {
+		status = write_n_bytes_to_channel(channel, current_page,
+						  current_position, bytes_to_write,
+						  &bytes_written, &error);
+	}
+
+	switch (status) {
+	case G_IO_STATUS_NORMAL:
+		current_position += bytes_written;
+		assert(current_position <= current_page->size);
+
+		if (metadata_requested)
+			metadata_fill += bytes_written;
+
+		if (current_position >= current_page->size) {
+			page_unref(current_page);
+			current_page = nullptr;
+
+			if (pages.empty()) {
+				/* all pages are sent: remove the
+				   event source */
+				write_source_id = 0;
+
+				return false;
+			}
+		}
+
+		return true;
+
+	case G_IO_STATUS_AGAIN:
+		return true;
+
+	case G_IO_STATUS_EOF:
+		/* client has disconnected */
+
+		Close();
+		return false;
+
+	case G_IO_STATUS_ERROR:
+		/* I/O error */
+
+		g_warning("failed to write to client: %s", error->message);
+		g_error_free(error);
+
+		Close();
+		return false;
+	}
+
+	/* unreachable */
+	Close();
+	return false;
+}
+
+static gboolean
+httpd_client_out_event(gcc_unused GIOChannel *source,
+		       gcc_unused GIOCondition condition, gpointer data)
+{
+	assert(condition == G_IO_OUT);
+
+	HttpdClient *client = (HttpdClient *)data;
+	return client->Write();
+}
+
+void
+HttpdClient::PushPage(struct page *page)
+{
+	if (state != RESPONSE)
+		/* the client is still writing the HTTP request */
+		return;
+
+	page_ref(page);
+	pages.push_back(page);
+
+	if (write_source_id == 0)
+		write_source_id = g_io_add_watch(channel, G_IO_OUT,
+						 httpd_client_out_event,
+						 this);
+}
+
+void
+HttpdClient::PushMetaData(struct page *page)
+{
+	if (metadata) {
+		page_unref(metadata);
+		metadata = nullptr;
+	}
+
+	g_return_if_fail (page);
+
+	page_ref(page);
+	metadata = page;
+	metadata_sent = false;
+}