Initial commit: video player - viper

Change-Id: Id5aa33598ce34659bad4a7a9ae5006bfb84f9bd1
Signed-off-by: Luca Muscariello <lumuscar+fdio@cisco.com>

4 files changed, 667 insertions, 0 deletions

diff --git a/websocketpp/logger/basic.hpp b/websocketpp/logger/basic.hpp
new file mode 100644
index 00000000..84514130
--- /dev/null
+++ b/websocketpp/logger/basic.hpp
@@ -0,0 +1,199 @@
+/*
+ * Copyright (c) 2014, 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_LOGGER_BASIC_HPP
+#define WEBSOCKETPP_LOGGER_BASIC_HPP
+
+/* Need a way to print a message to the log
+ *
+ * - timestamps
+ * - channels
+ * - thread safe
+ * - output to stdout or file
+ * - selective output channels, both compile time and runtime
+ * - named channels
+ * - ability to test whether a log message will be printed at compile time
+ *
+ */
+
+#include <websocketpp/logger/levels.hpp>
+
+#include <websocketpp/common/cpp11.hpp>
+#include <websocketpp/common/stdint.hpp>
+#include <websocketpp/common/time.hpp>
+
+#include <ctime>
+#include <iostream>
+#include <iomanip>
+#include <string>
+
+namespace websocketpp {
+namespace log {
+
+/// Basic logger that outputs to an ostream
+template <typename concurrency, typename names>
+class basic {
+public:
+    basic<concurrency,names>(channel_type_hint::value h =
+        channel_type_hint::access)
+      : m_static_channels(0xffffffff)
+      , m_dynamic_channels(0)
+      , m_out(h == channel_type_hint::error ? &std::cerr : &std::cout) {}
+
+    basic<concurrency,names>(std::ostream * out)
+      : m_static_channels(0xffffffff)
+      , m_dynamic_channels(0)
+      , m_out(out) {}
+
+    basic<concurrency,names>(level c, channel_type_hint::value h =
+        channel_type_hint::access)
+      : m_static_channels(c)
+      , m_dynamic_channels(0)
+      , m_out(h == channel_type_hint::error ? &std::cerr : &std::cout) {}
+
+    basic<concurrency,names>(level c, std::ostream * out)
+      : m_static_channels(c)
+      , m_dynamic_channels(0)
+      , m_out(out) {}
+
+    /// Destructor
+    ~basic<concurrency,names>() {}
+
+    /// Copy constructor
+    basic<concurrency,names>(basic<concurrency,names> const & other)
+     : m_static_channels(other.m_static_channels)
+     , m_dynamic_channels(other.m_dynamic_channels)
+     , m_out(other.m_out)
+    {}
+    
+#ifdef _WEBSOCKETPP_DEFAULT_DELETE_FUNCTIONS_
+    // no copy assignment operator because of const member variables
+    basic<concurrency,names> & operator=(basic<concurrency,names> const &) = delete;
+#endif // _WEBSOCKETPP_DEFAULT_DELETE_FUNCTIONS_
+
+#ifdef _WEBSOCKETPP_MOVE_SEMANTICS_
+    /// Move constructor
+    basic<concurrency,names>(basic<concurrency,names> && other)
+     : m_static_channels(other.m_static_channels)
+     , m_dynamic_channels(other.m_dynamic_channels)
+     , m_out(other.m_out)
+    {}
+
+#ifdef _WEBSOCKETPP_DEFAULT_DELETE_FUNCTIONS_
+    // no move assignment operator because of const member variables
+    basic<concurrency,names> & operator=(basic<concurrency,names> &&) = delete;
+#endif // _WEBSOCKETPP_DEFAULT_DELETE_FUNCTIONS_
+
+#endif // _WEBSOCKETPP_MOVE_SEMANTICS_
+
+    void set_ostream(std::ostream * out = &std::cout) {
+        m_out = out;
+    }
+
+    void set_channels(level channels) {
+        if (channels == names::none) {
+            clear_channels(names::all);
+            return;
+        }
+
+        scoped_lock_type lock(m_lock);
+        m_dynamic_channels |= (channels & m_static_channels);
+    }
+
+    void clear_channels(level channels) {
+        scoped_lock_type lock(m_lock);
+        m_dynamic_channels &= ~channels;
+    }
+
+    /// Write a string message to the given channel
+    /**
+     * @param channel The channel to write to
+     * @param msg The message to write
+     */
+    void write(level channel, std::string const & msg) {
+        scoped_lock_type lock(m_lock);
+        if (!this->dynamic_test(channel)) { return; }
+        *m_out << "[" << timestamp << "] "
+                  << "[" << names::channel_name(channel) << "] "
+                  << msg << "\n";
+        m_out->flush();
+    }
+
+    /// Write a cstring message to the given channel
+    /**
+     * @param channel The channel to write to
+     * @param msg The message to write
+     */
+    void write(level channel, char const * msg) {
+        scoped_lock_type lock(m_lock);
+        if (!this->dynamic_test(channel)) { return; }
+        *m_out << "[" << timestamp << "] "
+                  << "[" << names::channel_name(channel) << "] "
+                  << msg << "\n";
+        m_out->flush();
+    }
+
+    _WEBSOCKETPP_CONSTEXPR_TOKEN_ bool static_test(level channel) const {
+        return ((channel & m_static_channels) != 0);
+    }
+
+    bool dynamic_test(level channel) {
+        return ((channel & m_dynamic_channels) != 0);
+    }
+
+protected:
+    typedef typename concurrency::scoped_lock_type scoped_lock_type;
+    typedef typename concurrency::mutex_type mutex_type;
+    mutex_type m_lock;
+
+private:
+    // The timestamp does not include the time zone, because on Windows with the
+    // default registry settings, the time zone would be written out in full,
+    // which would be obnoxiously verbose.
+    //
+    // TODO: find a workaround for this or make this format user settable
+    static std::ostream & timestamp(std::ostream & os) {
+        std::time_t t = std::time(NULL);
+        std::tm lt = lib::localtime(t);
+        #ifdef _WEBSOCKETPP_PUTTIME_
+            return os << std::put_time(&lt,"%Y-%m-%d %H:%M:%S");
+        #else // Falls back to strftime, which requires a temporary copy of the string.
+            char buffer[20];
+            size_t result = std::strftime(buffer,sizeof(buffer),"%Y-%m-%d %H:%M:%S",&lt);
+            return os << (result == 0 ? "Unknown" : buffer);
+        #endif
+    }
+
+    level const m_static_channels;
+    level m_dynamic_channels;
+    std::ostream * m_out;
+};
+
+} // log
+} // websocketpp
+
+#endif // WEBSOCKETPP_LOGGER_BASIC_HPP
diff --git a/websocketpp/logger/levels.hpp b/websocketpp/logger/levels.hpp
new file mode 100644
index 00000000..cd7ccd69
--- /dev/null
+++ b/websocketpp/logger/levels.hpp
@@ -0,0 +1,203 @@
+/*
+ * Copyright (c) 2014, 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_LOGGER_LEVELS_HPP
+#define WEBSOCKETPP_LOGGER_LEVELS_HPP
+
+#include <websocketpp/common/stdint.hpp>
+
+namespace websocketpp {
+namespace log {
+
+/// Type of a channel package
+typedef uint32_t level;
+
+/// Package of values for hinting at the nature of a given logger.
+/**
+ * Used by the library to signal to the logging class a hint that it can use to
+ * set itself up. For example, the `access` hint indicates that it is an access
+ * log that might be suitable for being printed to an access log file or to cout
+ * whereas `error` might be suitable for an error log file or cerr. 
+ */
+struct channel_type_hint {
+    /// Type of a channel type hint value
+    typedef uint32_t value;
+    
+    /// No information
+    static value const none = 0;
+    /// Access log
+    static value const access = 1;
+    /// Error log
+    static value const error = 2;
+};
+
+/// Package of log levels for logging errors
+struct elevel {
+    /// Special aggregate value representing "no levels"
+    static level const none = 0x0;
+    /// Low level debugging information (warning: very chatty)
+    static level const devel = 0x1;
+    /// Information about unusual system states or other minor internal library
+    /// problems, less chatty than devel.
+    static level const library = 0x2;
+    /// Information about minor configuration problems or additional information
+    /// about other warnings.
+    static level const info = 0x4;
+    /// Information about important problems not severe enough to terminate
+    /// connections.
+    static level const warn = 0x8;
+    /// Recoverable error. Recovery may mean cleanly closing the connection with
+    /// an appropriate error code to the remote endpoint.
+    static level const rerror = 0x10;
+    /// Unrecoverable error. This error will trigger immediate unclean
+    /// termination of the connection or endpoint.
+    static level const fatal = 0x20;
+    /// Special aggregate value representing "all levels"
+    static level const all = 0xffffffff;
+
+    /// Get the textual name of a channel given a channel id
+    /**
+     * The id must be that of a single channel. Passing an aggregate channel
+     * package results in undefined behavior.
+     *
+     * @param channel The channel id to look up.
+     *
+     * @return The name of the specified channel.
+     */
+    static char const * channel_name(level channel) {
+        switch(channel) {
+            case devel:
+                return "devel";
+            case library:
+                return "library";
+            case info:
+                return "info";
+            case warn:
+                return "warning";
+            case rerror:
+                return "error";
+            case fatal:
+                return "fatal";
+            default:
+                return "unknown";
+        }
+    }
+};
+
+/// Package of log levels for logging access events
+struct alevel {
+    /// Special aggregate value representing "no levels"
+    static level const none = 0x0;
+    /// Information about new connections
+    /**
+     * One line for each new connection that includes a host of information
+     * including: the remote address, websocket version, requested resource,
+     * http code, remote user agent
+     */
+    static level const connect = 0x1;
+    /// One line for each closed connection. Includes closing codes and reasons.
+    static level const disconnect = 0x2;
+    /// One line per control frame
+    static level const control = 0x4;
+    /// One line per frame, includes the full frame header
+    static level const frame_header = 0x8;
+    /// One line per frame, includes the full message payload (warning: chatty)
+    static level const frame_payload = 0x10;
+    /// Reserved
+    static level const message_header = 0x20;
+    /// Reserved
+    static level const message_payload = 0x40;
+    /// Reserved
+    static level const endpoint = 0x80;
+    /// Extra information about opening handshakes
+    static level const debug_handshake = 0x100;
+    /// Extra information about closing handshakes
+    static level const debug_close = 0x200;
+    /// Development messages (warning: very chatty)
+    static level const devel = 0x400;
+    /// Special channel for application specific logs. Not used by the library.
+    static level const app = 0x800;
+    /// Access related to HTTP requests
+    static level const http = 0x1000;
+    /// One line for each failed WebSocket connection with details
+    static level const fail = 0x2000;
+    /// Aggregate package representing the commonly used core access channels
+    /// Connect, Disconnect, Fail, and HTTP
+    static level const access_core = 0x00003003;
+    /// Special aggregate value representing "all levels"
+    static level const all = 0xffffffff;
+
+    /// Get the textual name of a channel given a channel id
+    /**
+     * Get the textual name of a channel given a channel id. The id must be that
+     * of a single channel. Passing an aggregate channel package results in
+     * undefined behavior.
+     *
+     * @param channel The channelid to look up.
+     *
+     * @return The name of the specified channel.
+     */
+    static char const * channel_name(level channel) {
+        switch(channel) {
+            case connect:
+                return "connect";
+            case disconnect:
+                return "disconnect";
+            case control:
+                return "control";
+            case frame_header:
+                return "frame_header";
+            case frame_payload:
+                return "frame_payload";
+            case message_header:
+                return "message_header";
+            case message_payload:
+                return "message_payload";
+            case endpoint:
+                return "endpoint";
+            case debug_handshake:
+                return "debug_handshake";
+            case debug_close:
+                return "debug_close";
+            case devel:
+                return "devel";
+            case app:
+                return "application";
+            case http:
+                return "http";
+            case fail:
+                return "fail";
+            default:
+                return "unknown";
+        }
+    }
+};
+
+} // logger
+} // websocketpp
+
+#endif //WEBSOCKETPP_LOGGER_LEVELS_HPP
diff --git a/websocketpp/logger/stub.hpp b/websocketpp/logger/stub.hpp
new file mode 100644
index 00000000..2db6da7d
--- /dev/null
+++ b/websocketpp/logger/stub.hpp
@@ -0,0 +1,119 @@
+/*
+ * Copyright (c) 2014, 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_LOGGER_STUB_HPP
+#define WEBSOCKETPP_LOGGER_STUB_HPP
+
+#include <websocketpp/logger/levels.hpp>
+
+#include <websocketpp/common/cpp11.hpp>
+
+#include <string>
+
+namespace websocketpp {
+namespace log {
+
+/// Stub logger that ignores all input
+class stub {
+public:
+    /// Construct the logger
+    /**
+     * @param hint A channel type specific hint for how to construct the logger
+     */
+    explicit stub(channel_type_hint::value) {}
+
+    /// Construct the logger
+    /**
+     * @param default_channels A set of channels to statically enable
+     * @param hint A channel type specific hint for how to construct the logger
+     */
+    stub(level, channel_type_hint::value) {}
+    _WEBSOCKETPP_CONSTEXPR_TOKEN_ stub() {}
+
+    /// Dynamically enable the given list of channels
+    /**
+     * All operations on the stub logger are no-ops and all arguments are
+     * ignored
+     *
+     * @param channels The package of channels to enable
+     */
+    void set_channels(level) {}
+
+    /// Dynamically disable the given list of channels
+    /**
+     * All operations on the stub logger are no-ops and all arguments are
+     * ignored
+     *
+     * @param channels The package of channels to disable
+     */
+    void clear_channels(level) {}
+
+    /// Write a string message to the given channel
+    /**
+     * Writing on the stub logger is a no-op and all arguments are ignored
+     *
+     * @param channel The channel to write to
+     * @param msg The message to write
+     */
+    void write(level, std::string const &) {}
+
+    /// Write a cstring message to the given channel
+    /**
+     * Writing on the stub logger is a no-op and all arguments are ignored
+     *
+     * @param channel The channel to write to
+     * @param msg The message to write
+     */
+    void write(level, char const *) {}
+
+    /// Test whether a channel is statically enabled
+    /**
+     * The stub logger has no channels so all arguments are ignored and
+     * `static_test` always returns false.
+     *
+     * @param channel The package of channels to test
+     */
+    _WEBSOCKETPP_CONSTEXPR_TOKEN_ bool static_test(level) const {
+        return false;
+    }
+
+    /// Test whether a channel is dynamically enabled
+    /**
+     * The stub logger has no channels so all arguments are ignored and
+     * `dynamic_test` always returns false.
+     *
+     * @param channel The package of channels to test
+     */
+    bool dynamic_test(level) {
+        return false;
+    }
+};
+
+} // log
+} // websocketpp
+
+#endif // WEBSOCKETPP_LOGGER_STUB_HPP
diff --git a/websocketpp/logger/syslog.hpp b/websocketpp/logger/syslog.hpp
new file mode 100644
index 00000000..513abee4
--- /dev/null
+++ b/websocketpp/logger/syslog.hpp
@@ -0,0 +1,146 @@
+/*
+ * Copyright (c) 2014, 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.
+ *
+ *
+ * The initial version of this logging policy was contributed to the WebSocket++
+ * project by Tom Hughes.
+ */
+
+#ifndef WEBSOCKETPP_LOGGER_SYSLOG_HPP
+#define WEBSOCKETPP_LOGGER_SYSLOG_HPP
+
+#include <syslog.h>
+
+#include <websocketpp/logger/basic.hpp>
+
+#include <websocketpp/common/cpp11.hpp>
+#include <websocketpp/logger/levels.hpp>
+
+namespace websocketpp {
+namespace log {
+
+/// Basic logger that outputs to syslog
+template <typename concurrency, typename names>
+class syslog : public basic<concurrency, names> {
+public:
+    typedef basic<concurrency, names> base;
+
+    /// Construct the logger
+    /**
+     * @param hint A channel type specific hint for how to construct the logger
+     */
+    syslog<concurrency,names>(channel_type_hint::value hint =
+        channel_type_hint::access)
+      : basic<concurrency,names>(hint), m_channel_type_hint(hint) {}
+
+    /// Construct the logger
+    /**
+     * @param channels A set of channels to statically enable
+     * @param hint A channel type specific hint for how to construct the logger
+     */
+    syslog<concurrency,names>(level channels, channel_type_hint::value hint =
+        channel_type_hint::access)
+      : basic<concurrency,names>(channels, hint), m_channel_type_hint(hint) {}
+
+    /// Write a string message to the given channel
+    /**
+     * @param channel The channel to write to
+     * @param msg The message to write
+     */
+    void write(level channel, std::string const & msg) {
+        write(channel, msg.c_str());
+    }
+
+    /// Write a cstring message to the given channel
+    /**
+     * @param channel The channel to write to
+     * @param msg The message to write
+     */
+    void write(level channel, char const * msg) {
+        scoped_lock_type lock(base::m_lock);
+        if (!this->dynamic_test(channel)) { return; }
+        ::syslog(syslog_priority(channel), "[%s] %s",
+            names::channel_name(channel), msg);
+    }
+private:
+    typedef typename base::scoped_lock_type scoped_lock_type;
+
+    /// The default level is used for all access logs and any error logs that
+    /// don't trivially map to one of the standard syslog levels.
+    static int const default_level = LOG_INFO;
+
+    /// retrieve the syslog priority code given a WebSocket++ channel
+    /**
+     * @param channel The level to look up
+     * @return The syslog level associated with `channel`
+     */
+    int syslog_priority(level channel) const {
+        if (m_channel_type_hint == channel_type_hint::access) {
+            return syslog_priority_access(channel);
+        } else {
+            return syslog_priority_error(channel);
+        }
+    }
+
+    /// retrieve the syslog priority code given a WebSocket++ error channel
+    /**
+     * @param channel The level to look up
+     * @return The syslog level associated with `channel`
+     */
+    int syslog_priority_error(level channel) const {
+        switch (channel) {
+            case elevel::devel:
+                return LOG_DEBUG;
+            case elevel::library:
+                return LOG_DEBUG;
+            case elevel::info:
+                return LOG_INFO;
+            case elevel::warn:
+                return LOG_WARNING;
+            case elevel::rerror:
+                return LOG_ERR;
+            case elevel::fatal:
+                return LOG_CRIT;
+            default:
+                return default_level;
+        }
+    }
+
+    /// retrieve the syslog priority code given a WebSocket++ access channel
+    /**
+     * @param channel The level to look up
+     * @return The syslog level associated with `channel`
+     */
+    _WEBSOCKETPP_CONSTEXPR_TOKEN_ int syslog_priority_access(level) const {
+        return default_level;
+    }
+
+    channel_type_hint::value m_channel_type_hint;
+};
+
+} // log
+} // websocketpp
+
+#endif // WEBSOCKETPP_LOGGER_SYSLOG_HPP