LogSystem.cpp

/*
===========================================================================
Daemon BSD Source Code
Copyright (c) 2013-2016, Daemon Developers
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    * Redistributions in binary form must reproduce the above copyright
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      names of its contributors may be used to endorse or promote products
      derived from this software without specific prior written permission.

THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
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WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
DISCLAIMED. IN NO EVENT SHALL DAEMON DEVELOPERS BE LIABLE FOR ANY
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(INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
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===========================================================================
*/

#include <common/FileSystem.h>
#include "qcommon/q_shared.h"
#include "qcommon/qcommon.h"
#include "LogSystem.h"

namespace Log {
    static Target* targets[MAX_TARGET_ID];


    //TODO make me reentrant // or check it is actually reentrant when using for (Event e : events) do stuff
    //TODO think way more about thread safety
    void Dispatch(Log::Event event, int targetControl) {
        static std::vector<Log::Event> buffers[MAX_TARGET_ID];
        static std::recursive_mutex bufferLocks[MAX_TARGET_ID];

        if (Sys::IsProcessTerminating()) {
            return;
        }

        for (int i = 0; i < MAX_TARGET_ID; i++) {
            if ((targetControl >> i) & 1) {
                std::lock_guard<std::recursive_mutex> guard(bufferLocks[i]);
                auto& buffer = buffers[i];

                buffer.push_back(event);

                bool processed = false;
                if (targets[i]) {
                    processed = targets[i]->Process(buffer);
                }

                if (processed || buffer.size() > 512) {
                    buffer.clear();
                }
            }
        }
    }

    void RegisterTarget(TargetId id, Target* target) {
        targets[id] = target;
    }

    Target::Target() = default;

    void Target::Register(TargetId id) {
        Log::RegisterTarget(id, this);
    }

    //Log Targets
    //TODO: move them in their respective modules
    //TODO this one isn't multithreaded at all, need a rewrite of the consoles
    class TTYTarget : public Target {
        public:
            TTYTarget() {
                this->Register(TTY_CONSOLE);
            }

            virtual bool Process(const std::vector<Log::Event>& events) override {
                for (auto& event : events)  {
                    CON_Print(event.text.c_str());
                    CON_Print("\n");
                }
                return true;
            }
    };

    static TTYTarget tty;

    //TODO add a Callback on these that will make the logFile open a new file or something?
    static Cvar::Cvar<bool> useLogFile("logs.logFile.active", "are the logs sent in the logfile", Cvar::NONE, true);
    static Cvar::Cvar<std::string> logFileName("logs.logFile.filename", "the name of the logfile", Cvar::INIT | Cvar::TEMPORARY, "daemon.log");
    static Cvar::Cvar<bool> overwrite("logs.logFile.overwrite", "if true the logfile is deleted at each run else the logs are just appended", Cvar::INIT | Cvar::TEMPORARY, true);
    static Cvar::Cvar<bool> forceFlush("logs.logFile.forceFlush", "are all the logs flushed immediately (more accurate but slower)", Cvar::INIT | Cvar::TEMPORARY, false);
    class LogFileTarget: public Target {
        public:
            LogFileTarget() {
                this->Register(LOGFILE);
            }

            virtual bool Process(const std::vector<Log::Event>& events) override {
                //If we have no log file drop the events
                if (not useLogFile.Get()) {
                    return true;
                }

                if (logFile) {
                    for (auto& event : events) {
                        logFile.Printf("%s\n", event.text);
                    }
                    return true;
                } else {
                    return false;
                }
            }

            FS::File logFile;
    };

    static LogFileTarget logfile;

    void OpenLogFile() {
        //If we have no log file do nothing here
        if (not useLogFile.Get()) {
            return;
        }

        try {
            if (overwrite.Get()) {
                logfile.logFile = FS::HomePath::OpenWrite(logFileName.Get());
            } else {
                logfile.logFile = FS::HomePath::OpenAppend(logFileName.Get());
            }

            if (forceFlush.Get()) {
                logfile.logFile.SetLineBuffered(true);
            }
        } catch (std::system_error& err) {
            Sys::Error("Could not open log file %s: %s", logFileName.Get(), err.what());
        }
    }

    void FlushLogFile() {
        std::error_code err;
        logfile.logFile.Flush(err);
        if (err) {
            Log::Warn("Error flushing log file");
        }
    }
}