processinfo.hpp

Go to the documentation of this file.

//==================================================================================================
/// \file
/// This header file is part of sub-namespace #alib::lang::system of module \alib_basecamp of
/// the \aliblong.
///
/// \emoji :copyright: 2013-2024 A-Worx GmbH, Germany.
/// Published under \ref mainpage_license "Boost Software License".
//==================================================================================================
#ifndef HPP_ALIB_LANG_SYSTEM_PROCESSINFO
#define HPP_ALIB_LANG_SYSTEM_PROCESSINFO 1
#pragma once
#include "alib/strings/astring.hpp"
 
ALIB_ASSERT_MODULE(CAMP)
 
namespace alib { namespace  lang::system {
 
//==================================================================================================
///  This class represents process information
//==================================================================================================
class ProcessInfo
{
    // #############################################################################################
    // Fields
    // #############################################################################################
    protected:
        /// Information on the current process. This is initialized once, with the first invocation
        /// of #Current.
        ALIB_API static ProcessInfo    current;
 
    public:
        /// The process id as AString.
        uinteger    PID;
 
        /// The command line which invoked this process.
        AString     CmdLine;
 
        /// The name of the process.<br> Under GNU/Linux this is read from /proc/nnn/stat and may
        /// differ from #ExecFileName. Under Windows OS, it is he same as field #ExecFileName.
        AString     Name;
 
        /// The path of the executable (if available to us).
        AString     ExecFilePath;
 
        /// The file name of the executable (excluding #ExecFilePath). Under GNU/Linux,
        /// if we have no access to read that value, field #ExecFilePath will be empty
        /// while this field is filled with #Name.
        AString     ExecFileName;
 
    // #############################################################################################
    // Fields under unix like OS
    // #############################################################################################
    #if defined( __unix__ )  || DOXYGEN
 
            /// The parent's process id as AString. (Unix like OS / Mac OS only.)
            uinteger    PPID;
 
            /// The contents of /proc/PID/stat file. (Unix like OS only.)
            AString     Stat;
 
            /// The state field (2) within \ref Stat. (Unix like OS only.)
            AString     StatState;
 
            /// The process group field (4) within \ref Stat. (Unix like OS only.)
            AString     StatPGRP;
    #endif
 
    // #############################################################################################
    // Fields under Mac OS
    // #############################################################################################
    #if defined( __APPLE__ )
            uinteger    PPID;
    #endif
 
    // #############################################################################################
    // Fields under Windows OS
    // #############################################################################################
    #if defined( _WIN32 ) || DOXYGEN
        public:
 
             /// For console processes, this is the title displayed in the title bar. (Windows OS only.)
            AString     ConsoleTitle;
    #endif
 
 
    // #############################################################################################
    // Protected methods
    // #############################################################################################
    protected:
        //==========================================================================================
        /// Default constructor to create an empty instance
        //==========================================================================================
                        ProcessInfo()                   {}
 
 
        #if defined( __unix__ )
            //======================================================================================
            /// Reads a field from the data found in /proc/PID/stat.
            ///  @param fieldNo  The field number to read
            ///  @param target   The variable to store the result in
            ///  @returns \c true if successful.
            //======================================================================================
            bool        getStatField( int fieldNo, AString& target );
        #endif
 
        //==========================================================================================
        /// Internal get() method with different platform implementations.
        ///
        /// @param PID  The ID of the process information is requested on.
        ///             If a \e nulled string is provided, the current process is addressed.
        ///
        /// @return \c true on success, \c false otherwise.
        //==========================================================================================
        ALIB_API bool  get( uinteger PID  );
 
    // #############################################################################################
    // Interface
    // #############################################################################################
    public:
        #if defined( __unix__ ) || defined(__APPLE__)
            //======================================================================================
            /// Constructor that initializes this instance according to the process information
            /// received from the system.
            ///
            /// \note
            ///   This method is implemented for Unix like OS (incl. Mac OS) only.
            ///   On Windows OS, only information about the current process can be received
            ///   using static method #Current.
            ///
            /// @param processID    The ID of the process information is requested on.
            ///                     If a \e nulled string is provided, the current process is
            ///                     addressed.
            //======================================================================================
                                   ProcessInfo( uinteger processID  ) { get( processID ); }
 
            //======================================================================================
            /// Fills the fields of this instance according to the process information received from
            /// the system.
            ///
            /// \note
            ///   This method is implemented for Unix like OS (incl. Mac OS) only.
            ///   On Windows OS, only information about the current process can be received
            ///   using static method #Current.
            ///
            /// @param processID  The ID of the process information is requested on.
            ///                   If a \e nulled string is provided, the current process is
            ///                   addressed.
            ///
            /// @return \c true on success, \c false otherwise.
            //======================================================================================
            ALIB_API bool          Get( uinteger processID  ) { return get( processID ); }
        #endif
 
        //==========================================================================================
        /// Static method that receives information on the current process.
        ///
        /// @return A constant reference to a \c %ProcessInfo object representing the current process.
        //==========================================================================================
        ALIB_API static
        const ProcessInfo&         Current();
};
 
} // namespace [ lang::system]
 
/// Type alias in namespace \b alib.
using     ProcessInfo=        lang::system::ProcessInfo;
 
} // namespace [alib]
 
#endif // HPP_ALIB_LANG_SYSTEM_PROCESSINFO