/src/PcapPlusPlus/Common++/header/Logger.h

Source
#pragma once

#include <cstdio>
#include <cstdint>
#include <memory>
#include <array>
#include <mutex>
#include <ostream>
#include <sstream>
#include <functional>
#include "DeprecationUtils.h"
#include "ObjectPool.h"

#ifndef LOG_MODULE
# define LOG_MODULE UndefinedLogModule
#endif

// Use __FILE_NAME__ to avoid leaking complete full path
#ifdef __FILE_NAME__
# define PCAPPP_FILENAME __FILE_NAME__
#else
# define PCAPPP_FILENAME __FILE__
#endif

/// @file

// Compile time log levels.
// Allows for conditional removal of unwanted log calls at compile time.
#define PCPP_LOG_LEVEL_OFF 0
#define PCPP_LOG_LEVEL_ERROR 1
#define PCPP_LOG_LEVEL_WARN 2
#define PCPP_LOG_LEVEL_INFO 3
#define PCPP_LOG_LEVEL_DEBUG 4

// All log messages built via a PCPP_LOG_* macro below the PCPP_ACTIVE_LOG_LEVEL will be removed at compile time.
// Uses the PCPP_ACTIVE_LOG_LEVEL if it is defined, otherwise defaults to PCAP_LOG_LEVEL_DEBUG
#ifndef PCPP_ACTIVE_LOG_LEVEL
# define PCPP_ACTIVE_LOG_LEVEL PCPP_LOG_LEVEL_DEBUG
#endif  // !PCPP_ACTIVE_LOG_LEVEL

/// @namespace pcpp
/// @brief The main namespace for the PcapPlusPlus lib
namespace pcpp
{
  /// Cross-platform and thread-safe version of strerror
  /// @param errnum Value of errno
  /// @return String representation of the error number
  std::string getErrorString(int errnum);

  /// An enum representing all PcapPlusPlus modules
  enum LogModule : uint8_t
  {
    UndefinedLogModule,
    CommonLogModuleIpUtils,          ///< IP Utils module (Common++)
    CommonLogModuleTablePrinter,     ///< Table printer module (Common++)
    CommonLogModuleGenericUtils,     ///< Generic Utils (Common++)
    PacketLogModuleRawPacket,        ///< RawPacket module (Packet++)
    PacketLogModulePacket,           ///< Packet module (Packet++)
    PacketLogModuleLayer,            ///< Layer module (Packet++)
    PacketLogModuleAsn1Codec,        ///< Asn1Codec module (Packet++)
    PacketLogModuleArpLayer,         ///< ArpLayer module (Packet++)
    PacketLogModuleEthLayer,         ///< EthLayer module (Packet++)
    PacketLogModuleIPv4Layer,        ///< IPv4Layer module (Packet++)
    PacketLogModuleIPv6Layer,        ///< IPv6Layer module (Packet++)
    PacketLogModulePayloadLayer,     ///< PayloadLayer module (Packet++)
    PacketLogModuleTcpLayer,         ///< TcpLayer module (Packet++)
    PacketLogModuleUdpLayer,         ///< UdpLayer module (Packet++)
    PacketLogModuleVlanLayer,        ///< VlanLayer module (Packet++)
    PacketLogModuleHttpLayer,        ///< HttpLayer module (Packet++)
    PacketLogModulePPPoELayer,       ///< PPPoELayer module (Packet++)
    PacketLogModuleDnsLayer,         ///< DnsLayer module (Packet++)
    PacketLogModuleMplsLayer,        ///< MplsLayer module (Packet++)
    PacketLogModuleIcmpLayer,        ///< IcmpLayer module (Packet++)
    PacketLogModuleIcmpV6Layer,      ///< IcmpV6Layer module (Packet++)
    PacketLogModuleGreLayer,         ///< GreLayer module (Packet++)
    PacketLogModuleSSLLayer,         ///< SSLLayer module (Packet++)
    PacketLogModuleSllLayer,         ///< SllLayer module (Packet++)
    PacketLogModuleSll2Layer,        ///< Sll2Layer module (Packet++)
    PacketLogModuleNflogLayer,       ///< NflogLayer module (Packet++)
    PacketLogModuleDhcpLayer,        ///< DhcpLayer module (Packet++)
    PacketLogModuleDhcpV6Layer,      ///< DhcpV6Layer module (Packet++)
    PacketLogModuleIgmpLayer,        ///< IgmpLayer module (Packet++)
    PacketLogModuleSipLayer,         ///< SipLayer module (Packet++)
    PacketLogModuleSdpLayer,         ///< SdpLayer module (Packet++)
    PacketLogModuleRadiusLayer,      ///< RadiusLayer module (Packet++)
    PacketLogModuleGtpLayer,         ///< GtpLayer module (Packet++)
    PacketLogModuleBgpLayer,         ///< GtpLayer module (Packet++)
    PacketLogModuleSSHLayer,         ///< SSHLayer module (Packet++)
    PacketLogModuleVrrpLayer,        ///< Vrrp Record module (Packet++)
    PacketLogModuleTcpReassembly,    ///< TcpReassembly module (Packet++)
    PacketLogModuleIPReassembly,     ///< IPReassembly module (Packet++)
    PacketLogModuleIPSecLayer,       ///< IPSecLayers module (Packet++)
    PacketLogModuleNtpLayer,         ///< NtpLayer module (Packet++)
    PacketLogModuleTelnetLayer,      ///< TelnetLayer module (Packet++)
    PacketLogModuleStpLayer,         ///< StpLayer module (Packet++)
    PacketLogModuleLLCLayer,         ///< LLCLayer module (Packet++)
    PacketLogModuleNdpLayer,         ///< NdpLayer module (Packet++)
    PacketLogModuleFtpLayer,         ///< FtpLayer module (Packet++)
    PacketLogModuleSomeIpLayer,      ///< SomeIpLayer module (Packet++)
    PacketLogModuleSomeIpSdLayer,    ///< SomeIpSdLayer module (Packet++)
    PacketLogModuleWakeOnLanLayer,   ///< WakeOnLanLayer module (Packet++)
    PacketLogModuleSmtpLayer,        ///< SmtpLayer module (Packet++)
    PacketLogModuleWireGuardLayer,   ///< WireGuardLayer module (Packet++)
    PacketLogModuleDoIpLayer,        ///< DoipLayer module (Packet++)
    PacketLogModuleS7CommLayer,      ///< S7CommLayer module (Packet++)
    PcapLogModuleWinPcapLiveDevice,  ///< WinPcapLiveDevice module (Pcap++)
    PcapLogModuleRemoteDevice,       ///< WinPcapRemoteDevice module (Pcap++)
    PcapLogModuleLiveDevice,         ///< PcapLiveDevice module (Pcap++)
    PcapLogModuleFileDevice,         ///< FileDevice module (Pcap++)
    PcapLogModulePfRingDevice,       ///< PfRingDevice module (Pcap++)
    PcapLogModuleMBufRawPacket,      ///< MBufRawPacket module (Pcap++)
    PcapLogModuleDpdkDevice,         ///< DpdkDevice module (Pcap++)
    PcapLogModuleKniDevice,          ///< KniDevice module (Pcap++)
    PcapLogModuleXdpDevice,          ///< XdpDevice module (Pcap++)
    PcapLogModuleNetworkUtils,       ///< Network Utils module (Pcap++)
    NumOfLogModules
  };

  /// @struct LogSource
  /// Represents the source of a log message.
  /// Contains information about the source file, function, line number, and the log module.
  struct LogSource
  {
    /// Default constructor for LogSource.
    constexpr LogSource() = default;

    /// Constructor for LogSource with only the log module.
    /// @param logModule The log module.
    explicit constexpr LogSource(LogModule logModule) : logModule(logModule)
    {}

    /// Constructor for LogSource with all parameters.
    /// @param logModule The log module.
    /// @param file The source file.
    /// @param function The source function.
    /// @param line The line number.
    constexpr LogSource(LogModule logModule, const char* file, const char* function, int line)
        : file(file), function(function), line(line), logModule(logModule)
    {}

    const char* file = nullptr;               /**< The source file. */
    const char* function = nullptr;           /**< The source function. */
    int line = 0;                             /**< The line number. */
    LogModule logModule = UndefinedLogModule; /**< The log module. */
  };

  /// An enum representing the log level. Currently 4 log levels are supported: Off, Error, Info and Debug. Info is
  /// the default log level
  enum class LogLevel : uint8_t
  {
    Off = PCPP_LOG_LEVEL_OFF,      ///< No log messages are emitted.
    Error = PCPP_LOG_LEVEL_ERROR,  ///< Error level logs are emitted.
    Warn = PCPP_LOG_LEVEL_WARN,    ///< Warning level logs and above are emitted.
    Info = PCPP_LOG_LEVEL_INFO,    ///< Info level logs and above are emitted.
    Debug = PCPP_LOG_LEVEL_DEBUG   ///< Debug level logs and above are emitted.
  };

  inline std::ostream& operator<<(std::ostream& ostr, LogLevel lvl)
  {
    return ostr << static_cast<std::underlying_type_t<LogLevel>>(lvl);
  }

  // Forward declaration
  class Logger;

  namespace internal
  {
    /// @class LogContext
    /// @brief A context encapsulating the details of a single log message to be passed to the Logger.
    class LogContext
    {
    public:
      friend class pcpp::Logger;

      /// @brief Creates a context with an empty message with Info level and no source.
      LogContext() = default;

      /// @brief Creates a context with an empty message with the given level and source.
      /// @param level The log level for this message.
      /// @param source The log source.
      explicit LogContext(LogLevel level, LogSource const& source = {}) : m_Source(source), m_Level(level)
      {}

      /// @brief Initializes the context with an empty message and the given level and source.
      /// @param level The log level for this message.
      /// @param source The log source.
      void init(LogLevel level, LogSource const& source)
      {
        m_Source = source;
        m_Level = level;
        m_Stream.clear();
        m_Stream.str({});
      }

      /// @brief Appends to the message.
      /// @param value The value to append.
      /// @return A reference to this context.
      template <class T> LogContext& operator<<(T const& value)
      {
        m_Stream << value;
        return *this;
      }

    private:
      std::ostringstream m_Stream;
      LogSource m_Source;
      LogLevel m_Level = LogLevel::Info;
    };
  }  // namespace internal

  /// @class Logger
  /// PcapPlusPlus logger manager.
  /// PcapPlusPlus uses this logger to output both error and debug logs.
  /// There are currently 3 log levels: Logger#Error, Logger#Info and Logger#Debug.
  ///
  /// PcapPlusPlus is divided into modules (described in #LogModule enum). The user can set the log level got each
  /// module or to all modules at once. The default is Logger#Info which outputs only error messages. Changing log
  /// level for modules can be done dynamically while the application is running.
  ///
  /// The logger also exposes a method to retrieve the last error log message.
  ///
  /// Logs are printed to console by default in a certain format. The user can set a different print function to
  /// change the format or to print to other media (such as files, etc.).
  ///
  /// PcapPlusPlus logger is a singleton which can be reached from anywhere in the code.
  ///
  /// Note: Logger#Info level logs are currently only used in DPDK devices to set DPDK log level to RTE_LOG_NOTICE.
  class Logger
  {
  public:
    Logger(const Logger&) = delete;
    Logger& operator=(const Logger&) = delete;

    // Deprecated, Use the LogLevel in the pcpp namespace instead.
    using LogLevel = pcpp::LogLevel;
    PCPP_DEPRECATED("Use the LogLevel in the pcpp namespace instead.")
    static const LogLevel Error = LogLevel::Error;
    PCPP_DEPRECATED("Use the LogLevel in the pcpp namespace instead.")
    static const LogLevel Info = LogLevel::Info;
    PCPP_DEPRECATED("Use the LogLevel in the pcpp namespace instead.")
    static const LogLevel Debug = LogLevel::Debug;

    /// @typedef LogPrinter
    /// Log printer callback. Used for printing the logs in a custom way.
    /// @param[in] logLevel The log level for this log message
    /// @param[in] logMessage The log message
    /// @param[in] file The source file in PcapPlusPlus code the log message is coming from
    /// @param[in] method The method in PcapPlusPlus code the log message is coming from
    /// @param[in] line The line in PcapPlusPlus code the log message is coming from
    /// @remarks The printer callback should support being called from multiple threads simultaneously.
    using LogPrinter = std::function<void(LogLevel logLevel, const std::string& logMessage, const std::string& file,
                                          const std::string& method, const int line)>;

    /// A static method for converting the log level enum to a string.
    /// @param[in] logLevel A log level enum
    /// @return The log level as a string
    static std::string logLevelAsString(LogLevel logLevel);

    /// Get the log level for a certain module
    /// @param[in] module PcapPlusPlus module
    /// @return The log level set for this module
    LogLevel getLogLevel(LogModule module)
    {
      return m_LogModulesArray[module];
    }

    /// Set the log level for a certain PcapPlusPlus module
    /// @param[in] module PcapPlusPlus module
    /// @param[in] level The log level to set the module to
    void setLogLevel(LogModule module, LogLevel level)
    {
      m_LogModulesArray[module] = level;
    }

    /// Check whether a certain module is set to debug log level
    /// @param[in] module PcapPlusPlus module
    /// @return True if this module log level is "debug". False otherwise
    bool isDebugEnabled(LogModule module) const
    {
      return m_LogModulesArray[module] == LogLevel::Debug;
    }

    /// @brief Check whether a log level should be emitted by the logger.
    /// @param level The level of the log message.
    /// @param module PcapPlusPlus module
    /// @return True if the message should be emitted. False otherwise.
    bool shouldLog(LogLevel level, LogModule module) const
    {
      return level != LogLevel::Off && m_LogModulesArray[module] >= level;
    }

    /// Set all PcapPlusPlus modules to a certain log level
    /// @param[in] level The log level to set all modules to
    void setAllModulesToLogLevel(LogLevel level)
    {
      for (int i = 1; i < NumOfLogModules; i++)
      {
        m_LogModulesArray[i] = level;
      }
    }

    /// Set a custom log printer.
    /// @param[in] printer A log printer function that will be called for every log message
    void setLogPrinter(LogPrinter printer)
    {
      m_LogPrinter = printer;
    }

    /// Set the log printer back to the default printer
    void resetLogPrinter();

    /// @return Get the last error message
    std::string getLastError() const
    {
      return { m_LastError.data() };
    }

    /// Suppress logs in all PcapPlusPlus modules
    void suppressLogs()
    {
      m_LogsEnabled = false;
    }

    /// Enable logs in all PcapPlusPlus modules
    void enableLogs()
    {
      m_LogsEnabled = true;
    }

    /// Get an indication if logs are currently enabled.
    /// @return True if logs are currently enabled, false otherwise
    bool logsEnabled() const
    {
      return m_LogsEnabled;
    }

    /// @brief Controls if the logger should use a pool of LogContext objects.
    ///
    /// If enabled is set to false, preallocate and maxPoolSize are ignored.
    /// @param enabled True to enable context pooling, false to disable.
    /// @param preallocate The number of LogContext objects to preallocate in the pool.
    /// @param maxPoolSize The maximum number of LogContext objects to keep in the pool.
    /// @remarks Disabling the pooling clears the pool.
    void useContextPooling(bool enabled, std::size_t preallocate = 2, std::size_t maxPoolSize = 10)
    {
      m_UseContextPooling = enabled;

      if (m_UseContextPooling)
      {
        m_LogContextPool.setMaxSize(maxPoolSize);

        if (preallocate > 0)
        {
          m_LogContextPool.preallocate(preallocate);
        }
      }
      else
      {
        // Clear the pool if we're disabling pooling.
        m_LogContextPool.clear();
      }
    }

    /// Get access to Logger singleton
    /// @todo: make this singleton thread-safe/
    /// @return a pointer to the Logger singleton
    static Logger& getInstance()
    {
      static Logger instance;
      return instance;
    }

    /// @brief Creates a new LogContext with Info level and no source.
    /// @return A new LogContext.
    std::unique_ptr<internal::LogContext> createLogContext();

    /// @brief Creates a new LogContext with the given level and source.
    /// @param level The log level for this message.
    /// @param source The log source.
    /// @return A new LogContext.
    std::unique_ptr<internal::LogContext> createLogContext(LogLevel level, LogSource const& source = {});

    /// @brief Directly emits a log message bypassing all level checks.
    /// @param source The log source.
    /// @param level The log level for this message. This is only used for the log printer.
    /// @param message The log message.
    void emit(LogSource const& source, LogLevel level, std::string const& message);

    /// @brief Directly emits a log message bypassing all level checks.
    /// @param message The log message.
    void emit(std::unique_ptr<internal::LogContext> message);

  private:
    bool m_LogsEnabled;
    std::array<LogLevel, NumOfLogModules> m_LogModulesArray{};
    LogPrinter m_LogPrinter;

    // Using an array instead of std::string because MinGW has issues with TLS destruction.
    // The array should be large enough to hold most PCPP errors without cutoffs.
    static thread_local std::array<char, 255> m_LastError;

    bool m_UseContextPooling = true;
    // Keep a maximum of 10 LogContext objects in the pool.
    internal::DynamicObjectPool<internal::LogContext> m_LogContextPool{ 10, 2 };

    // private c'tor - this class is a singleton
    Logger();
  };

}  // namespace pcpp

#define PCPP_LOG(level, message)                                                                                       \
  do                                                                                                                 \
  {                                                                                                                  \
    auto& logger = pcpp::Logger::getInstance();                                                                    \
    if (logger.shouldLog(level, LOG_MODULE))                                                                       \
    {                                                                                                              \
      auto ctx =                                                                                                 \
          logger.createLogContext(level, pcpp::LogSource(LOG_MODULE, PCAPPP_FILENAME, __FUNCTION__, __LINE__));  \
      (*ctx) << message;                                                                                         \
      logger.emit(std::move(ctx));                                                                               \
    }                                                                                                              \
  } while (0)

#if PCPP_ACTIVE_LOG_LEVEL >= PCPP_LOG_LEVEL_DEBUG
# define PCPP_LOG_DEBUG(message) PCPP_LOG(pcpp::LogLevel::Debug, message)
#else
# define PCPP_LOG_DEBUG(message) (void)0
#endif

#if PCPP_ACTIVE_LOG_LEVEL >= PCPP_LOG_LEVEL_WARN
# define PCPP_LOG_WARN(message) PCPP_LOG(pcpp::LogLevel::Warn, message)
#else
# define PCPP_LOG_WARN(message) (void)0
#endif

#if PCPP_ACTIVE_LOG_LEVEL >= PCPP_LOG_LEVEL_INFO
# define PCPP_LOG_INFO(message) PCPP_LOG(pcpp::LogLevel::Info, message)
#else
# define PCPP_LOG_INFO(message) (void)0
#endif

#if PCPP_ACTIVE_LOG_LEVEL >= PCPP_LOG_LEVEL_ERROR
# define PCPP_LOG_ERROR(message) PCPP_LOG(pcpp::LogLevel::Error, message)
#else
# define PCPP_LOG_ERROR(message) (void)0
#endif

Coverage Report

Created: 2026-10-17 07:09