LogStream.h

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// Copyright (c) 2002-present, OpenMS Inc. -- EKU Tuebingen, ETH Zurich, and FU Berlin
// SPDX-License-Identifier: BSD-3-Clause
//
// --------------------------------------------------------------------------
// $Maintainer: Chris Bielow $
// $Authors: Chris Bielow, Stephan Aiche, Andreas Bertsch$
// --------------------------------------------------------------------------
 
#pragma once
 
#include <OpenMS/CONCEPT/Macros.h>
#include <OpenMS/DATASTRUCTURES/StringUtils.h>
 
#include <atomic>
#include <sstream>
#include <iostream>
#include <list>
#include <vector>
#include <ctime>
#include <map>
 
namespace OpenMS
{
  class Colorizer;
 
  namespace Logger
  {
    // forward declarations
    class LogStream;
 
    class OPENMS_DLLAPI LogStreamBuf :
      public std::streambuf
    {
 
      friend class LogStream;
 
public:
 
 
      static const time_t MAX_TIME;
      static const std::string UNKNOWN_LOG_LEVEL;
 
 
 
 
      LogStreamBuf(const std::string& log_level = UNKNOWN_LOG_LEVEL, Colorizer* col = nullptr);
 
      LogStreamBuf(LogStreamBuf* source_buf, Colorizer* col = nullptr);
 
      ~LogStreamBuf() override;
 
 
 
 
      int sync() override;
 
      int overflow(int c = -1) override;
 
 
 
 
      void setLevel(std::string level);
 
 
      std::string getLevel();
 
      struct OPENMS_DLLAPI StreamStruct
      {
        std::ostream * stream;
        std::string         prefix;
        Size id;
 
        StreamStruct() :
          stream(nullptr),
          id(0)
        {}
      };
 
      void clearCache();
 
protected:
 
      void distribute_(const std::string& outstring);
 
      void distributeNew_(const std::string& line);
 
      std::string expandPrefix_(const std::string & prefix, time_t time) const;
 
      std::list<StreamStruct>& getStreamList_();
      const std::list<StreamStruct>& getStreamList_() const;
 
      void updateFromParent_();
 
      void updateFromParentLocked_();
 
      void rebuildStreamList_();
 
      bool guarded_(const std::ostream* stream) const;
 
      std::list<StreamStruct>& prefixableStreams_();
 
      void destinationsChanged_();
 
      char * pbuf_ = nullptr;
      std::string             level_;
      std::list<StreamStruct> stream_list_;  
      std::string             incomplete_line_;
      LogStreamBuf* parent_ = nullptr;
      std::atomic<Size> version_{0};
      Size parent_version_ = 0;
      std::list<StreamStruct> own_streams_;
      std::vector<Size> hidden_ids_;
      std::vector<const std::ostream*> guarded_streams_;
      Colorizer* colorizer_ = nullptr; 
 
 
      struct LogCacheStruct
      {
        Size timestamp;
        int counter;
      };
 
      Size log_cache_counter_ = 0;
 
      std::map<std::string, LogCacheStruct> log_cache_;
      std::map<Size, std::string> log_time_cache_;
 
      bool isInCache_(std::string const & line);
 
      std::string addToCache_(std::string const & line);
 
      Size getNextLogCounter_();
 
      int syncLF_();
 
      std::vector<std::string> repeatSummaries_() const;
 
      void forgetRepeatsAfterChange_(const std::vector<Size>& previous);
 
      std::vector<Size> destinations_() const;
 
      void write_(StreamStruct& s, const std::string& line);
    };
 
    class OPENMS_DLLAPI LogStream :
      public std::ostream
    {
public:
 
 
 
      LogStream(LogStreamBuf * buf = nullptr, bool delete_buf = true, std::ostream * stream = nullptr);
 
      ~LogStream() override;
 
 
 
      LogStreamBuf * rdbuf();
 
      LogStreamBuf * operator->();
 
 
 
 
      void setLevel(std::string level);
 
 
      std::string getLevel();
 
 
      void insert(std::ostream & s);
 
      void remove(std::ostream & s);
 
      void removeAllStreams();
 
      void setPrefix(const std::ostream & s, const std::string & prefix);
 
 
      void setPrefix(const std::string & prefix);
 
      void flush();
 
      void flushIncomplete();
 
      bool hasStream(std::ostream & stream);
private:
 
      typedef std::list<LogStreamBuf::StreamStruct>::iterator StreamIterator;
 
      StreamIterator findStream_(const std::ostream & stream);
      bool hasStream_(std::ostream & stream);
      bool bound_() const;
 
      friend struct ThreadLocalLogAccess;
 
      friend class LogSinkGuard;
 
      struct GuardedRemoval
      {
        bool reinsert = false;
        std::string prefix;
        Size id = 0;
      };
 
      GuardedRemoval removeForGuard_(std::ostream& s);
 
      void restoreForGuard_(std::ostream& s, const GuardedRemoval& removal);
 
      GuardedRemoval detachLocked_(std::ostream& s);
 
      LogStream* threadLocalFollower_();
 
      void drain_();
 
      void followParent_();
 
      void updateState_();
 
      bool delete_buffer_;
 
    }; //LogStream
 
    class OPENMS_DLLAPI LogSinkGuard
    {
    public:
      LogSinkGuard(LogStream& log_stream, std::ostream& stream)
        : log_stream_(log_stream), stream_(stream), was_attached_(log_stream.hasStream(stream))
      {
        if (!was_attached_)
        {
          return;
        }
        // Drains pending output first, so that pre-guard text reaches this sink before it is detached.
        removal_ = log_stream_.removeForGuard_(stream_);
      }
 
      ~LogSinkGuard()
      {
        if (!was_attached_)
        {
          return;
        }
        log_stream_.restoreForGuard_(stream_, removal_);
      }
 
      // Non-copyable and non-movable
      LogSinkGuard(const LogSinkGuard&) = delete;
      LogSinkGuard& operator=(const LogSinkGuard&) = delete;
      LogSinkGuard(LogSinkGuard&&) = delete;
      LogSinkGuard& operator=(LogSinkGuard&&) = delete;
 
    private:
      LogStream& log_stream_;
      std::ostream& stream_;
      const bool was_attached_;
      LogStream::GuardedRemoval removal_;
    };
 
  } // namespace Logger
 
  //
  // Thread-Local Log Stream Accessors
  //
  // These functions return thread-local LogStream instances, eliminating data races
  // in the logging system. Each thread gets its own buffers and state.
  // See GitHub Issue #8596 for details on the race conditions this fixes.
  //
  // Each thread-local stream writes to the destinations of the corresponding global stream
  // (getGlobalLog*()). A change of the global destinations (e.g. via LogConfigHandler) takes
  // effect in every thread at its next message, including threads that have logged before;
  // a destination removed from the global stream is not written to afterwards, so it may be
  // destroyed. Changes of a thread-local stream itself apply on top, to its thread only
  // (see LogStream::insert()).
  //
  // A thread-local stream without destinations (e.g. the debug stream, unless debug output is enabled) does
  // not format messages: it is in a failed state (badbit) until it has a destination again. The arguments of
  // a message are still evaluated, except with OPENMS_LOG_DEBUG, which skips the whole message then.
  // Each call of these accessors (as in the OPENMS_LOG_* macros) applies changes
  // of the global destinations to the calling thread's stream; a reference kept across such a change picks it up
  // with the next call on that thread, or with insert() or remove() on it.
  //
  // RESTRICTIONS:
  // - Change the global configuration from one thread at a time.
  // - OpenMP thread pools reuse threads, so thread_local state (e.g. local changes) persists across parallel regions.
  //
 
  OPENMS_DLLAPI Logger::LogStream& getThreadLocalLogFatal();
 
  OPENMS_DLLAPI Logger::LogStream& getThreadLocalLogError();
 
  OPENMS_DLLAPI Logger::LogStream& getThreadLocalLogWarn();
 
  OPENMS_DLLAPI Logger::LogStream& getThreadLocalLogInfo();
 
  OPENMS_DLLAPI Logger::LogStream& getThreadLocalLogDebug();
 
  OPENMS_DLLAPI void setConsoleDebugLogging(bool enabled);
 
  //
  // Logging Macros (thread-safe via thread-local streams)
  //
 
#define OPENMS_LOG_FATAL_ERROR \
  OpenMS::getThreadLocalLogFatal() << __FILE__ << "(" << __LINE__ << "): "
 
#define OPENMS_LOG_ERROR \
  OpenMS::getThreadLocalLogError()
 
#define OPENMS_LOG_WARN \
  OpenMS::getThreadLocalLogWarn()
 
#define OPENMS_LOG_INFO \
  OpenMS::getThreadLocalLogInfo()
 
  namespace Logger
  {
    struct LogVoidify
    {
      void operator&(std::ostream&) const {}
    };
  }
 
#define OPENMS_LOG_DEBUG \
  !OpenMS::getThreadLocalLogDebug().good() ? (void)0 : OpenMS::Logger::LogVoidify() & \
  OpenMS::getThreadLocalLogDebug() << past_last_slash(__FILE__) << "(" << __LINE__ << "): "
 
#define OPENMS_LOG_DEBUG_NOFILE \
  !OpenMS::getThreadLocalLogDebug().good() ? (void)0 : OpenMS::Logger::LogVoidify() & OpenMS::getThreadLocalLogDebug()
 
 
  OPENMS_DLLAPI Logger::LogStream& getGlobalLogFatal();
 
  OPENMS_DLLAPI Logger::LogStream& getGlobalLogError();
 
  OPENMS_DLLAPI Logger::LogStream& getGlobalLogWarn();
 
  OPENMS_DLLAPI Logger::LogStream& getGlobalLogInfo();
 
  OPENMS_DLLAPI Logger::LogStream& getGlobalLogDebug();
 
 
} // namespace OpenMS