add new 'fixed' message buffer strategy

websocketpp/message_buffer/fixed.hpp

@@ -0,0 +1,147 @@
+/*
+ * Copyright (c) 2013, Peter Thorson. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *     * Redistributions of source code must retain the above copyright
+ *       notice, this list of conditions and the following disclaimer.
+ *     * Redistributions in binary form must reproduce the above copyright
+ *       notice, this list of conditions and the following disclaimer in the
+ *       documentation and/or other materials provided with the distribution.
+ *     * Neither the name of the WebSocket++ Project nor the
+ *       names of its contributors may be used to endorse or promote products
+ *       derived from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL PETER THORSON BE LIABLE FOR ANY
+ * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+ * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+ * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+ * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+ * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ */
+
+#ifndef WEBSOCKETPP_MESSAGE_BUFFER_FIXED_HPP
+#define WEBSOCKETPP_MESSAGE_BUFFER_FIXED_HPP
+
+#include <websocketpp/common/memory.hpp>
+#include <websocketpp/frame.hpp>
+
+namespace websocketpp {
+namespace message_buffer {
+namespace fixed {
+
+struct policy {
+    typedef websocketpp::message_buffer::fixed_message message;
+    typedef websocketpp::message_buffer::fixed::con_msg_manager con_msg_manager;
+    typedef websocketpp::message_buffer::fixed::endpoint_msg_manager endpoint_msg_manager;
+};
+
+/// A connection message manager that allocates a new message for each
+/// request.
+class con_msg_manager {
+public:
+    typedef con_msg_manager type;
+
+    typedef std::shared_ptr<type> ptr;
+
+    typedef typename policy::message::ptr message_ptr;
+
+    con_msg_manager()
+      : m_incoming_message(new message())
+      , m_incoming_message_busy(false)
+      , m_outgoing_message(new message())
+      , m_outgoing_message_busy(false) {}
+
+    /// Get an empty message buffer
+    /**
+     * @return A shared pointer to an empty new message
+     */
+    message_ptr get_message() {
+        return message_ptr(new message(type::shared_from_this()));
+    }
+
+    message_ptr get_incoming_data_message() {
+        if (m_incoming_message_busy) {
+            return message_ptr();
+        } else {
+            return m_incoming_message;
+        }
+    }
+
+    message_ptr get_incoming_data_message(frame::opcode::value op, size_t size) {
+        if (m_incoming_message_busy) {
+            return message_ptr();
+        } else {
+            m_incoming_message.set_opcode(op);
+            m_incoming_message.reserve(size);
+            return m_incoming_message;
+        }
+    }
+
+    message_ptr get_outgoing_data_message() {
+        if (m_outgoing_message_busy) {
+            return message_ptr();
+        } else {
+            return m_outgoing_message;
+        }
+    }
+
+    message_ptr get_outgoing_data_message(frame::opcode::value op, size_t size) {
+        if (m_outgoing_message_busy) {
+            return message_ptr();
+        } else {
+            m_outgoing_message.set_opcode(op);
+            m_outgoing_message.reserve(size);
+            return m_outgoing_message;
+        }
+    }
+
+    message_ptr get_incoming_control_message(frame::opcode::value op, size_t size) {
+        return message_ptr(new message(op,size));
+    }
+
+    message_ptr get_outgoing_control_message(frame::opcode::value op, size_t size) {
+        return message_ptr(new message(op,size));
+    }
+
+    bool recycle(message_ptr msg) {
+        if (msg == m_incoming_message) {
+            m_incoming_message_busy = false;
+        } else if (msg == m_outgoing_message) {
+            m_outgoing_message_busy = false;
+        } else {
+            // error
+        }
+    }
+private:
+    message_ptr m_incoming_message;
+    bool m_incoming_message_busy;
+    message_ptr m_outgoing_message;
+    bool m_outgoing_message_busy;
+};
+
+/// An endpoint message manager that allocates a new manager for each
+/// connection.
+class endpoint_msg_manager {
+public:
+    typedef policy::con_msg_manager::ptr con_msg_man_ptr;
+
+    /// Get a pointer to a connection message manager
+    /**
+     * @return A pointer to the requested connection message manager.
+     */
+    con_msg_man_ptr get_manager() const {
+        return con_msg_man_ptr(new con_msg_manager());
+    }
+};
+
+} // namespace fixed
+} // namespace message_buffer
+} // namespace websocketpp
+
+#endif // WEBSOCKETPP_MESSAGE_BUFFER_FIXED_HPP

websocketpp/message_buffer/fixed_message.hpp

@@ -0,0 +1,313 @@
+/*
+ * Copyright (c) 2013, Peter Thorson. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *     * Redistributions of source code must retain the above copyright
+ *       notice, this list of conditions and the following disclaimer.
+ *     * Redistributions in binary form must reproduce the above copyright
+ *       notice, this list of conditions and the following disclaimer in the
+ *       documentation and/or other materials provided with the distribution.
+ *     * Neither the name of the WebSocket++ Project nor the
+ *       names of its contributors may be used to endorse or promote products
+ *       derived from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL PETER THORSON BE LIABLE FOR ANY
+ * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+ * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+ * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+ * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+ * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ */
+
+#ifndef WEBSOCKETPP_MESSAGE_BUFFER_FIXED_MESSAGE_HPP
+#define WEBSOCKETPP_MESSAGE_BUFFER_FIXED_MESSAGE_HPP
+
+#include <websocketpp/common/memory.hpp>
+#include <websocketpp/frame.hpp>
+
+#include <string>
+
+namespace websocketpp {
+namespace message_buffer {
+
+/* # message:
+ * object that stores a message while it is being sent or received. Contains
+ * the message payload itself, the message header, the extension data, and the
+ * opcode.
+ *
+ * # connection_message_manager:
+ * An object that manages all of the message_buffers associated with a given
+ * connection. Impliments the get_message_buffer(size) method that returns
+ * a message buffer at least size bytes long.
+ *
+ * Message buffers are reference counted with shared ownership semantics. Once
+ * requested from the manager the requester and it's associated downstream code
+ * may keep a pointer to the message indefinitely at a cost of extra resource
+ * usage. Once the reference count drops to the point where the manager is the
+ * only reference the messages is recycled using whatever method is implemented
+ * in the manager.
+ *
+ * # endpoint_message_manager:
+ * An object that manages connection_message_managers. Impliments the
+ * get_message_manager() method. This is used once by each connection to
+ * request the message manager that they are supposed to use to manage message
+ * buffers for their own use.
+ *
+ * TYPES OF CONNECTION_MESSAGE_MANAGERS
+ * - allocate a message with the exact size every time one is requested
+ * - maintain a pool of pre-allocated messages and return one when needed.
+ *   Recycle previously used messages back into the pool
+ *
+ * TYPES OF ENDPOINT_MESSAGE_MANAGERS
+ *  - allocate a new connection manager for each connection. Message pools
+ *    become connection specific. This increases memory usage but improves
+ *    concurrency.
+ *  - allocate a single connection manager and share a pointer to it with all
+ *    connections created by this endpoint. The message pool will be shared
+ *    among all connections, improving memory usage and performance at the cost
+ *    of reduced concurrency
+ */
+
+
+/// Represents a buffer for a single WebSocket message.
+/**
+ *
+ *
+ */
+class fixed_message {
+public:
+    typedef lib::shared_ptr<fixed_message> ptr;
+
+    /// Construct an empty message
+    /**
+     * Construct an empty message
+     */
+    message()
+      : m_prepared(false)
+      , m_fin(true)
+      , m_terminal(false)
+      , m_compressed(false) {}
+
+    /// Construct a message and fill in some values
+    /**
+     *
+     */
+    message(frame::opcode::value op, size_t size = 128)
+      : m_opcode(op)
+      , m_prepared(false)
+      , m_fin(true)
+      , m_terminal(false)
+      , m_compressed(false)
+    {
+        m_payload.reserve(size);
+    }
+
+    /// Return whether or not the message has been prepared for sending
+    /**
+     * The prepared flag indicates that the message has been prepared by a
+     * websocket protocol processor and is ready to be written to the wire.
+     *
+     * @return whether or not the message has been prepared for sending
+     */
+    bool get_prepared() const {
+        return m_prepared;
+    }
+
+    /// Set or clear the flag that indicates that the message has been prepared
+    /**
+     * This flag should not be set by end user code without a very good reason.
+     *
+     * @param value The value to set the prepared flag to
+     */
+    void set_prepared(bool value) {
+        m_prepared = value;
+    }
+
+    /// Return whether or not the message is flagged as compressed
+    /**
+     * @return whether or not the message is/should be compressed
+     */
+    bool get_compressed() const {
+        return m_compressed;
+    }
+
+    /// Set or clear the compression flag
+    /**
+     * The compression flag is used to indicate whether or not the message is
+     * or should be compressed. Compression is not guaranteed. Both endpoints
+     * must support a compression extension and the connection must have had
+     * that extension negotiated in its handshake.
+     *
+     * @param value The value to set the compressed flag to
+     */
+    void set_compressed(bool value) {
+        m_compressed = value;
+    }
+
+    /// Get whether or not the message is terminal
+    /**
+     * Messages can be flagged as terminal, which results in the connection
+     * being close after they are written rather than the implementation going
+     * on to the next message in the queue. This is typically used internally
+     * for close messages only.
+     *
+     * @return Whether or not this message is marked terminal
+     */
+    bool get_terminal() const {
+        return m_terminal;
+    }
+
+    /// Set the terminal flag
+    /**
+     * This flag should not be set by end user code without a very good reason.
+     *
+     * @see get_terminal()
+     *
+     * @param value The value to set the terminal flag to.
+     */
+    void set_terminal(bool value) {
+        m_terminal = value;
+    }
+    /// Read the fin bit
+    /**
+     * A message with the fin bit set will be sent as the last message of its
+     * sequence. A message with the fin bit cleared will require subsequent
+     * frames of opcode continuation until one of them has the fin bit set.
+     *
+     * The remote end likely will not deliver any bytes until the frame with the fin
+     * bit set has been received.
+     *
+     * @return Whether or not the fin bit is set
+     */
+    bool get_fin() const {
+        return m_fin;
+    }
+
+    /// Set the fin bit
+    /**
+     * @see get_fin for a more detailed explaination of the fin bit
+     *
+     * @param value The value to set the fin bit to.
+     */
+    void set_fin(bool value) {
+        m_fin = value;
+    }
+
+    /// Return the message opcode
+    frame::opcode::value get_opcode() const {
+        return m_opcode;
+    }
+
+    /// Set the opcode
+    void set_opcode(frame::opcode::value op) {
+        m_opcode = op;
+    }
+
+    /// Return the prepared frame header
+    /**
+     * This value is typically set by a websocket protocol processor
+     * and shouldn't be tampered with.
+     */
+    std::string const & get_header() const {
+        return m_header;
+    }
+
+    /// Set prepared frame header
+    /**
+     * Under normal circumstances this should not be called by end users
+     *
+     * @param header A string to set the header to.
+     */
+    void set_header(std::string const & header) {
+        m_header = header;
+    }
+
+    std::string const & get_extension_data() const {
+        return m_extension_data;
+    }
+
+    /// Get a reference to the payload string
+    /**
+     * @return A const reference to the message's payload string
+     */
+    std::string const & get_payload() const {
+        return m_payload;
+    }
+
+    /// Get a non-const reference to the payload string
+    /**
+     * @return A reference to the message's payload string
+     */
+    std::string & get_raw_payload() {
+        return m_payload;
+    }
+
+    /// Set payload data
+    /**
+     * Set the message buffer's payload to the given value.
+     *
+     * @param payload A string to set the payload to.
+     */
+    void set_payload(std::string const & payload) {
+        m_payload = payload;
+    }
+
+    /// Set payload data
+    /**
+     * Set the message buffer's payload to the given value.
+     *
+     * @param payload A pointer to a data array to set to.
+     * @param len The length of new payload in bytes.
+     */
+    void set_payload(void const * payload, size_t len) {
+        m_payload.reserve(len);
+        char const * pl = static_cast<char const *>(payload);
+        m_payload.assign(pl, pl + len);
+    }
+
+    /// Append payload data
+    /**
+     * Append data to the message buffer's payload.
+     *
+     * @param payload A string containing the data array to append.
+     */
+    void append_payload(std::string const & payload) {
+        m_payload.append(payload);
+    }
+
+    /// Append payload data
+    /**
+     * Append data to the message buffer's payload.
+     *
+     * @param payload A pointer to a data array to append
+     * @param len The length of payload in bytes
+     */
+    void append_payload(void const * payload, size_t len) {
+        m_payload.reserve(m_payload.size()+len);
+        m_payload.append(static_cast<char const *>(payload),len);
+    }
+
+    void reserve(size_t size) {
+        m_payload.reserve(size);
+    }
+private:
+    std::string                 m_header;
+    std::string                 m_extension_data;
+    std::string                 m_payload;
+    frame::opcode::value        m_opcode;
+    bool                        m_prepared;
+    bool                        m_fin;
+    bool                        m_terminal;
+    bool                        m_compressed;
+};
+
+} // namespace message_buffer
+} // namespace websocketpp
+
+#endif // WEBSOCKETPP_MESSAGE_BUFFER_FIXED_MESSAGE_HPP