Log.hpp

/******************************************************************************
* Copyright (c) 2011, Howard Butler, hobu.inc@gmail.com
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#pragma once

#include <pdal/pdal_internal.hpp>

#include <pdal/util/FileUtils.hpp>
#include <iosfwd>
#include <memory>

// Adapted from http://drdobbs.com/cpp/201804215

namespace pdal
{


/// pdal::Log is a logging object that is provided by pdal::Stage to
/// facilitate logging operations.
class PDAL_DLL Log
{
public:

    /// Constructs a pdal::Log instance.
    /// @param leaderString A string to presage all log entries with
    /// @param outputName A filename or one of 'stdout', 'stdlog', or 'stderr'
    ///                   to use for outputting log information.
    Log(std::string const& leaderString, std::string const& outputName);

    /// Constructs a pdal::Log instance.
    /// @param leaderString A string to presage all log entries with
    /// @param v An existing std::ostream to use for logging (instead of the
    ///          the instance creating its own)
    Log(std::string const& leaderString, std::ostream* v);

    /** @name Destructor
    */
    /// The destructor will clean up its own internal log stream, but it will
    /// not touch one that is given via the constructor
    ~Log();

    /** @name Logging level
    */
    /// @return the logging level of the pdal::Log instance
    LogLevel::Enum getLevel()
    {
        return m_level;
    }

    /// Sets the logging level of the pdal::Log instance
    /// @param v logging level to use for get() comparison operations
    void setLevel(LogLevel::Enum v)
    {
        m_level = v;
    }

    /// @return A string representing the LogLevel
    std::string getLevelString(LogLevel::Enum v) const;

    /** @name Log stream operations
    */
    /// @return the stream object that is currently being used to for log
    /// operations regardless of logging level of the instance.
    std::ostream* getLogStream()
    {
        return m_log;
    }

    /// Returns the log stream given the logging level.
    /// @param level logging level to request
    /// If the logging level asked for with
    /// pdal::Log::get is less than the logging level of the pdal::Log instance
    std::ostream& get(LogLevel::Enum level = LogLevel::Info);

    /// Sets the floating point precision
    void floatPrecision(int level);

    /// Clears the floating point precision settings of the streams
    void clearFloat();

protected:
    std::ostream *m_log;
    std::ostream *m_nullStream;

private:
    Log(const Log&);
    Log& operator =(const Log&);

    void makeNullStream();

    LogLevel::Enum m_level;
    bool m_deleteStreamOnCleanup;
    std::string m_leader;
};

typedef std::shared_ptr<Log> LogPtr;

} // namespace pdal