New logging implementation

Features:
	* Works without ifdefs
	* Configurable with commandline arguments
	* Log level configurable per file
	* Thread safe

4 files changed, 719 insertions, 0 deletions

diff --git a/nxcomp/src/Log.cpp b/nxcomp/src/Log.cpp
new file mode 100644
index 000000000..3ff47aea8
--- /dev/null
+++ b/nxcomp/src/Log.cpp
@@ -0,0 +1,121 @@
+/**************************************************************************/
+/*                                                                        */
+/* Copyright (c) 2001, 2011 NoMachine (http://www.nomachine.com)          */
+/* Copyright (c) 2008-2014 Oleksandr Shneyder <o.shneyder@phoca-gmbh.de>  */
+/* Copyright (c) 2014-2016 Ulrich Sibiller <uli42@gmx.de>                 */
+/* Copyright (c) 2014-2016 Mihai Moldovan <ionic@ionic.de>                */
+/* Copyright (c) 2011-2016 Mike Gabriel <mike.gabriel@das-netzwerkteam.de>*/
+/* Copyright (c) 2015-2016 Qindel Group (http://www.qindel.com)           */
+/*                                                                        */
+/* NXCOMP, NX protocol compression and NX extensions to this software     */
+/* are copyright of the aforementioned persons and companies.             */
+/*                                                                        */
+/* Redistribution and use of the present software is allowed according    */
+/* to terms specified in the file LICENSE.nxcomp which comes in the       */
+/* source distribution.                                                   */
+/*                                                                        */
+/* All rights reserved.                                                   */
+/*                                                                        */
+/* NOTE: This software has received contributions from various other      */
+/* contributors, only the core maintainers and supporters are listed as   */
+/* copyright holders. Please contact us, if you feel you should be listed */
+/* as copyright holder, as well.                                          */
+/*                                                                        */
+/**************************************************************************/
+
+
+#include <stdio.h>
+#include <iostream>
+#include <fstream>
+#include <sstream>
+#include <iomanip>
+
+#include "Log.h"
+
+NXLog nx_log;
+
+
+bool NXLog::will_log() const
+{
+    std::map<std::string, NXLogLevel>::const_iterator item = per_file_levels_.find(current_file());
+
+    if ( item != per_file_levels_.end() )
+    {
+        return current_level() <= item->second;
+    }
+    else
+    {
+        return current_level() <= level();
+    }
+}
+
+
+std::string NXLog::stamp_to_string(const NXLogStamp& stamp) const
+{
+    std::ostringstream oss;
+
+    static const char* level_names[] = {
+        "FATAL",
+        "ERROR",
+        "WARN ",
+        "INFO ",
+        "DEBUG"
+    };
+
+    if ( log_level() )
+        oss << ((stamp.level() >=0 && stamp.level() < NXLOG_LEVEL_COUNT ) ? level_names[stamp.level()] : "???") << " ";
+
+    if ( log_time() )
+    {
+        struct timeval timestamp = stamp.timestamp();
+        struct tm timeinfo;
+
+        localtime_r(&timestamp.tv_sec, &timeinfo);
+
+        if ( log_unix_time() )
+        {
+            oss << timestamp.tv_sec;
+        }
+        else
+        {
+            #if __cplusplus >= 201103L && (!defined(__GNUC__) || __GNUC__ >= 5)
+            oss << " " << std::put_time(&timeinfo, "%Y/%m/%d %H:%M:%S");
+            #else
+            oss << timestamp.tv_sec;
+            #endif
+        }
+
+        oss << "." << std::setw(3) << std::setfill('0') << (int)(timestamp.tv_usec / 1000) << " ";
+    }
+
+    if ( log_location() )
+        oss << stamp.file() << "/" << stamp.function() << ":" << stamp.line()  << " ";
+
+    if ( log_thread_id() )
+    {
+        if ( thread_name().empty() )
+            oss << pthread_self() << " ";
+        else
+            oss << "[" << thread_name() << "] ";
+    }
+
+    return oss.str();
+}
+
+NXLog& operator<< (NXLog& out, const NXLogStamp& value)
+{
+    out.current_level( value.level() );
+    out.current_file( value.file() );
+
+    // Writing an NXLogStamp to the stream indicates the start of a new entry.
+    // If there's any content in the buffer, we flush it to finalize the previous
+    // log entry.
+    if ( out.synchronized() )
+        out.flush();
+
+
+    out << out.stamp_to_string(value);
+
+    return out;
+}
+
diff --git a/nxcomp/src/Log.h b/nxcomp/src/Log.h
new file mode 100644
index 000000000..f4ee66e1f
--- /dev/null
+++ b/nxcomp/src/Log.h
@@ -0,0 +1,500 @@
+/**************************************************************************/
+/*                                                                        */
+/* Copyright (c) 2001, 2011 NoMachine (http://www.nomachine.com)          */
+/* Copyright (c) 2008-2014 Oleksandr Shneyder <o.shneyder@phoca-gmbh.de>  */
+/* Copyright (c) 2014-2016 Ulrich Sibiller <uli42@gmx.de>                 */
+/* Copyright (c) 2014-2016 Mihai Moldovan <ionic@ionic.de>                */
+/* Copyright (c) 2011-2016 Mike Gabriel <mike.gabriel@das-netzwerkteam.de>*/
+/* Copyright (c) 2015-2016 Qindel Group (http://www.qindel.com)           */
+/*                                                                        */
+/* NXCOMP, NX protocol compression and NX extensions to this software     */
+/* are copyright of the aforementioned persons and companies.             */
+/*                                                                        */
+/* Redistribution and use of the present software is allowed according    */
+/* to terms specified in the file LICENSE.nxcomp which comes in the       */
+/* source distribution.                                                   */
+/*                                                                        */
+/* All rights reserved.                                                   */
+/*                                                                        */
+/* NOTE: This software has received contributions from various other      */
+/* contributors, only the core maintainers and supporters are listed as   */
+/* copyright holders. Please contact us, if you feel you should be listed */
+/* as copyright holder, as well.                                          */
+/*                                                                        */
+/**************************************************************************/
+
+
+#ifndef NXLog_H
+#define NXLog_H
+
+#include <iostream>
+#include <fstream>
+#include <sstream>
+#include <sys/time.h>
+
+#include <map>
+#include <stdlib.h>
+#include <string.h>
+
+/** Log severity level */
+enum NXLogLevel
+{
+    NXFATAL,
+    NXERROR,
+    NXWARNING,
+    NXINFO,
+    NXDEBUG,
+    NXLOG_LEVEL_COUNT
+};
+
+
+/**
+ * Log timestamp class
+ *
+ * Stores the timestamp, file, function, line number and log level.
+ * Acts as a manipulator on the NXLog class, telling it a new log
+ * severity level. For instance:
+ *
+ *     nx_log << NXLogStamp(...,NXINFO)
+ *
+ * Tells nx_log that now NXINFO type messages are being logged. This
+ * will be applied until a new NXLogStamp with a different level
+ * is sent to the NXLog.
+ */
+class NXLogStamp
+{
+    private:
+    std::string file_;
+    std::string function_;
+    size_t line_;
+    NXLogLevel level_;
+    struct timeval timestamp_;
+
+    public:
+    /** File where the event occurred */
+    std::string file() const
+    {
+        return file_;
+    }
+
+    /** Function where the event occurred */
+    std::string function() const
+    {
+        return function_;
+    }
+
+    /** Line where the event occurred */
+    size_t line() const
+    {
+        return line_;
+    }
+
+    /** Severity level of the event */
+    NXLogLevel level() const
+    {
+        return level_;
+    }
+
+    /** Time of the event */
+    struct timeval timestamp() const
+    {
+        return timestamp_;
+    }
+
+
+    NXLogStamp(const char *file, const char *function, int line, NXLogLevel level)
+    {
+        file_      = std::string(file);
+        function_  = std::string(function);
+        line_      = line;
+        level_     = level;
+        gettimeofday(&timestamp_, NULL);
+    }
+
+};
+
+
+/**
+ * Log class
+ *
+ * Logs events to a stream, filters by file/level
+ */
+class NXLog
+{
+    NXLogLevel level_;
+
+    std::ostream *stream_;
+    std::map< std::string, NXLogLevel > per_file_levels_;
+    bool synchronized_;
+    size_t  thread_buffer_size_;
+    pthread_mutex_t output_lock_;
+    pthread_key_t tls_key_;
+
+    bool log_level_;
+    bool log_time_;
+    bool log_unix_time_;
+    bool log_location_;
+    bool log_thread_id_;
+
+    typedef struct per_thread_data_s
+    {
+        NXLogLevel          current_level;
+        std::string*        current_file;
+        std::string*        thread_name;
+        std::stringstream*  buffer;
+        NXLog*              log_obj;
+    } per_thread_data;
+
+
+    static void free_thread_data(void* arg)
+    {
+        per_thread_data *pdt = (per_thread_data*)arg;
+
+        if ( !pdt )
+            return;
+
+        if ( pdt->log_obj ) {
+            // Ensure the buffer is flushed before thread deletion
+            pdt->log_obj->flush(pdt);
+        }
+
+        delete pdt->current_file;
+        delete pdt->thread_name;
+        delete pdt->buffer;
+        delete pdt;
+    }
+
+    per_thread_data* get_data_int() const
+    {
+        per_thread_data *ret = NULL;
+
+        if ( (ret = (per_thread_data*)pthread_getspecific(tls_key_)) == NULL )
+        {
+            ret = new per_thread_data;
+            ret->current_level = NXDEBUG;
+            ret->buffer = new std::stringstream();
+            ret->current_file = new std::string();
+            ret->thread_name = new std::string();
+            ret->log_obj = const_cast<NXLog*>(this);
+            pthread_setspecific(tls_key_, ret);
+        }
+
+        return ret;
+    }
+
+    per_thread_data* get_data()
+    {
+        return get_data_int();
+    }
+
+    const per_thread_data* get_data() const
+    {
+        return get_data_int();
+    }
+
+    /** Convert NXLogStamp to string according to the current configuration */
+    std::string stamp_to_string(const NXLogStamp& stamp) const;
+
+    /**
+     * Internal flush function
+     *
+     * When a thread is being terminated and free_thread_data gets called,
+     * the TLS key gets set to NULL before the call to free_thread_data,
+     * and the destructor function gets the old value.
+     *
+     * This means that get_data() stops working correctly, and we need
+     * to be able to pass the old pointer.
+     */
+    void flush(per_thread_data *pdt)
+    {
+        const std::string str = pdt->buffer->str();
+
+        if (!str.empty())
+        {
+            pthread_mutex_lock(&output_lock_);
+            (*stream()) << str;
+            pthread_mutex_unlock(&output_lock_);
+            pdt->buffer->str("");
+        }
+    }
+
+
+    public:
+    NXLog()
+    {
+        stream_             = &std::cerr;
+        level_              = NXDEBUG;
+        synchronized_       = true;
+        thread_buffer_size_ = 1024;
+        log_level_          = false;
+        log_time_           = false;
+        log_unix_time_      = false;
+        log_location_       = false;
+        log_thread_id_      = false;
+
+        if ( pthread_key_create(&tls_key_, free_thread_data) != 0 )
+        {
+            std::cerr << "pthread_key_create failed" << std::endl;
+            abort();
+        }
+
+    }
+
+    ~NXLog()
+    {
+        per_thread_data *pdt = get_data();
+
+        // Flush any remaining output and delete TLS data
+        free_thread_data(pdt);
+
+        pthread_key_delete(tls_key_);
+    }
+
+    /** Minimum severity level to output */
+    NXLogLevel level() const
+    {
+        return level_;
+    }
+
+    void level(NXLogLevel level)
+    {
+        level_ = level;
+    }
+
+
+    /** Current severity level */
+    NXLogLevel current_level() const
+    {
+        return get_data()->current_level;
+    }
+
+    void current_level(NXLogLevel level)
+    {
+        get_data()->current_level = level;
+    }
+
+    /** Source file from which messages are currently originating */
+    std::string current_file() const
+    {
+        return *get_data()->current_file;
+    }
+
+    void current_file(std::string val)
+    {
+        *get_data()->current_file = val;
+    }
+
+    std::ostream* stream() const
+    {
+        return stream_;
+    }
+
+    void stream(std::ostream *stream)
+    {
+        flush();
+        stream_ = stream;
+    }
+
+    bool synchronized() const {
+        return synchronized_;
+    }
+
+    void synchronized(bool val) {
+        synchronized_ = val;
+    }
+
+    bool log_level() const
+    {
+        return log_level_;
+    }
+
+    void log_level(bool val)
+    {
+        log_level_ = val;
+    }
+
+    bool log_time() const
+    {
+        return log_time_;
+    }
+
+    void log_time(bool val)
+    {
+        log_time_ = val;
+    }
+
+    bool log_unix_time() const
+    {
+        return log_unix_time_;
+    }
+
+    void log_unix_time(bool val)
+    {
+        log_unix_time_ = val;
+    }
+
+    bool log_location() const
+    {
+        return log_location_;
+    }
+
+    void log_location(bool val)
+    {
+        log_location_ = val;
+    }
+
+    bool log_thread_id() const
+    {
+        return log_thread_id_;
+    }
+
+    void log_thread_id(bool val)
+    {
+        log_thread_id_ = val;
+    }
+
+
+    void flush()
+    {
+        per_thread_data *pdt = get_data();
+        flush(pdt);
+    }
+
+    std::string thread_name() const
+    {
+        return *get_data()->thread_name;
+    }
+
+    void thread_name(std::string str)
+    {
+        *get_data()->thread_name = str;
+    }
+
+    void thread_name(const char *str)
+    {
+        *get_data()->thread_name = str;
+    }
+
+    /**
+     * True if a message sent to the NXLog object will be sent to the output
+     *
+     * This considers two things:
+     *
+     * If there's a per-file log level, then it is used
+     * Otherwise the global log level is used.
+     *
+     * If the log level permits the current message to be output, then the
+     * return value is true.
+     */
+    bool will_log() const;
+
+
+    /**
+     * This catches std::flush
+     */
+    NXLog&  operator<<(std::ostream& (*F)(std::ostream&))
+    {
+        if ( will_log() )
+        {
+            if ( synchronized() )
+            {
+                per_thread_data *pdt = get_data();
+                (*pdt->buffer) << F;
+                flush();
+            }
+            else
+            {
+                *(stream()) << F;
+            }
+        }
+
+        return *this;
+    }
+
+    template<typename T>
+    friend NXLog& operator<<(NXLog& out, const T& value);
+
+    friend NXLog& operator<< (NXLog& out, const NXLogStamp& value);
+};
+
+
+extern NXLog nx_log;
+
+
+#define nxstamp(l) NXLogStamp(__FILE__, __func__, __LINE__, l)
+
+
+#define nxdbg    nx_log << nxstamp(NXDEBUG)
+#define nxinfo   nx_log << nxstamp(NXINFO)
+#define nxwarn   nx_log << nxstamp(NXWARNING)
+#define nxerr    nx_log << nxstamp(NXERROR)
+#define nxfatal  nx_log << nxstamp(NXFATAL)
+
+
+NXLog& operator<< (NXLog& out, const NXLogStamp& value);
+
+
+template <typename T>
+bool has_newline(T value)
+{
+    return false;
+}
+
+template <char*>
+static bool has_newline(char *value)
+{
+    return strstr(value, "\n") != NULL;
+}
+
+template <char>
+static bool has_newline(char value)
+{
+    return value == '\n';
+}
+
+template <std::string&>
+static bool has_newline(std::string &value)
+{
+    return value.find_first_of("\n") != std::string::npos;
+}
+
+static size_t ss_length(std::stringstream *ss)
+{
+    size_t pos = ss->tellg();
+    size_t ret = 0;
+    ss->seekg(0, std::ios::end);
+    ret = ss->tellg();
+    ss->seekg(pos, std::ios::beg);
+    return ret;
+}
+
+template <typename T>
+NXLog& operator<<(NXLog& out, const T& value)
+{
+    if ( out.will_log() )
+    {
+        if ( out.synchronized() )
+        {
+            // In synchronized mode, we buffer data until a newline, std::flush, or the buffer
+            // gets full. Then we dump the whole thing at once to the output stream, synchronizing
+            // with a mutex.
+            NXLog::per_thread_data *pdt = out.get_data();
+            (*pdt->buffer) << value;
+
+            if ( ss_length(pdt->buffer) >= out.thread_buffer_size_ || has_newline(value) )
+                out.flush();
+
+        }
+        else
+        {
+            // In async mode we just dump data on the output stream as-is.
+            // Multithreaded code will have ugly output.
+            *(out.stream()) << value;
+        }
+
+    }
+
+    return out;
+}
+
+#endif
diff --git a/nxcomp/src/Loop.cpp b/nxcomp/src/Loop.cpp
index 4292e7b9a..681a5a1ef 100644
--- a/nxcomp/src/Loop.cpp
+++ b/nxcomp/src/Loop.cpp
@@ -101,6 +101,7 @@ typedef int socklen_t;
 
 #include "Message.h"
 #include "ChannelEndPoint.h"
+#include "Log.h"
 
 //
 // System specific defines.
@@ -9339,6 +9340,102 @@ int ParseCommandLineOptions(int argc, const char **argv)
 
           return -1;
         }
+        case 'd':
+        {
+          if ( argi+1 >= argc )
+          {
+            PrintUsageInfo(nextArg, 0);
+            return -1;
+          }
+
+          int level = 0;
+          errno = 0;
+          level = strtol(argv[argi+1], NULL, 10);
+
+          if ( errno && (level == 0) )
+          {
+            cerr << "Warning: Failed to parse log level. Ignoring option." << std::endl;
+          }
+          if ( level < 0 )
+          {
+            cerr << "Warning: Log level must be a positive integer. Ignoring option." << std::endl;
+            level = nx_log.level();
+          }
+          else if ( level >= NXLOG_LEVEL_COUNT )
+          {
+            cerr << "Warning: Log level is greater than the maximum " << NXLOG_LEVEL_COUNT-1 << ". Setting to the maximum." << std::endl;
+            level = NXLOG_LEVEL_COUNT-1;
+          }
+
+          nx_log.level( (NXLogLevel)level );
+
+          argi++;
+          break;
+
+        }
+        case 'o':
+        {
+          if ( argi + 1 >= argc )
+          {
+            PrintUsageInfo(nextArg, 0);
+            return -1;
+          }
+
+          std::ofstream *logfile = new std::ofstream();
+
+          // Unbuffered output
+          logfile->rdbuf()->pubsetbuf(0, 0);
+          logfile->open(argv[argi+1], std::ofstream::app);
+
+          if ( logfile->is_open() )
+          {
+            nx_log.stream(logfile);
+          }
+          else
+          {
+            cerr << "Failed to open log file " << argv[argi+1] << endl;
+            return -1;
+          }
+
+          argi++;
+          break;
+        }
+        case 'f':
+        {
+          if ( argi + 1 >= argc )
+          {
+            PrintUsageInfo(nextArg, 0);
+            return -1;
+          }
+
+          const char *format = argv[argi+1];
+          size_t pos = 0;
+
+          nx_log.log_level(false);
+          nx_log.log_time(false);
+          nx_log.log_unix_time(false);
+          nx_log.log_location(false);
+          nx_log.log_thread_id(false);
+
+          for(pos =0;pos<strlen(format);pos++)
+          {
+            switch(format[pos])
+            {
+              case '0': break;
+              case 't': nx_log.log_time(true); break;
+              case 'u': nx_log.log_time(true); nx_log.log_unix_time(true); break;
+              case 'l': nx_log.log_level(true); break;
+              case 'T': nx_log.log_thread_id(true); break;
+              case 'L': nx_log.log_location(true); break;
+              default : cerr << "Unrecognized format specifier: " << format[pos] << endl; break;
+            }
+          }
+
+          argi++;
+          break;
+        }
+
+
         default:
         {
           PrintUsageInfo(nextArg, 1);
diff --git a/nxcomp/src/Makefile.am b/nxcomp/src/Makefile.am
index ad05a6cbf..682ddbaca 100644
--- a/nxcomp/src/Makefile.am
+++ b/nxcomp/src/Makefile.am
@@ -114,6 +114,7 @@ libXcomp_la_SOURCES =					\
     WriteBuffer.cpp					\
     XidCache.cpp					\
     Z.cpp						\
+    Log.cpp						\
     $(NULL)
 
 libXcomp_la_LIBADD =					\