add support for thread safe writing to log.

4 files changed, 91 insertions, 0 deletions

diff --git a/src/gui/gui.cpp b/src/gui/gui.cpp
index f84750e17..8dbaec952 100644
--- a/src/gui/gui.cpp
+++ b/src/gui/gui.cpp
@@ -49,6 +49,7 @@
 #include "resources/resourcemanager.h"
 
 #include "utils/langs.h"
+#include "utils/timer.h"
 
 #include <guichan/exception.hpp>
 
@@ -107,6 +108,7 @@ Gui::Gui() :
     mFocusListeners(),
     mForegroundColor(Theme::getThemeColor(Theme::TEXT)),
     mForegroundColor2(Theme::getThemeColor(Theme::TEXT_OUTLINE)),
+    mTime(0),
     mCustomCursor(false),
     mDoubleClick(true)
 {
@@ -366,6 +368,14 @@ void Gui::slowLogic()
         mNpcFont->slowLogic(5);
     if (windowContainer)
         windowContainer->slowLogic();
+
+    const int time = cur_time;
+    if (mTime != time)
+    {
+        logger->flush();
+        mTime = time;
+    }
+
     BLOCK_END("Gui::slowLogic")
 }
 
diff --git a/src/gui/gui.h b/src/gui/gui.h
index 56895b699..7c34fc5cf 100644
--- a/src/gui/gui.h
+++ b/src/gui/gui.h
@@ -197,6 +197,7 @@ class Gui final : public gcn::Gui
         FocusListenerList mFocusListeners;
         gcn::Color mForegroundColor;
         gcn::Color mForegroundColor2;
+        int mTime;
         bool mCustomCursor;                 /**< Show custom cursor */
         bool mDoubleClick;
 };
diff --git a/src/logger.cpp b/src/logger.cpp
index bac895954..a4cc5096b 100644
--- a/src/logger.cpp
+++ b/src/logger.cpp
@@ -64,6 +64,9 @@ Logger *logger = nullptr;          // Log object
 
 Logger::Logger() :
     mLogFile(),
+    mDelayedLog(),
+    mMutex(SDL_CreateMutex()),
+    mThreadLocked(false),
     mLogToStandardOut(true),
     mDebugLog(false)
 {
@@ -73,6 +76,7 @@ Logger::~Logger()
 {
     if (mLogFile.is_open())
         mLogFile.close();
+    SDL_DestroyMutex(mMutex);
 }
 
 void Logger::setLogFile(const std::string &logFilename)
@@ -169,6 +173,60 @@ void Logger::log(const char *const log_text, ...)
     delete [] buf;
 }
 
+void Logger::log_r(const char *const log_text, ...)
+{
+    SDL_mutexP(mMutex);
+
+    unsigned size = 1024;
+    if (strlen(log_text) * 3 > size)
+        size = static_cast<unsigned>(strlen(log_text) * 3);
+
+    char* buf = new char[size + 1];
+    va_list ap;
+
+    // Use a temporary buffer to fill in the variables
+    va_start(ap, log_text);
+    vsnprintf(buf, size, log_text, ap);
+    buf[size] = 0;
+    va_end(ap);
+
+    // Get the current system time
+    timeval tv;
+    gettimeofday(&tv, nullptr);
+
+    // Print the log entry
+    std::stringstream timeStr;
+    DATESTREAM
+    LOG_ANDROID(buf)
+
+    if (mLogFile.is_open())
+    {
+        timeStr << buf << std::endl;
+        mThreadLocked = true;
+        mDelayedLog.push_back(timeStr.str());
+        mThreadLocked = false;
+    }
+
+    if (mLogToStandardOut)
+        std::cout << timeStr.str() << buf << std::endl;
+
+    // Delete temporary buffer
+    delete [] buf;
+
+    SDL_mutexV(mMutex);
+}
+
+void Logger::flush()
+{
+    if (!mThreadLocked)
+    {
+        SDL_mutexP(mMutex);
+        FOR_EACH (std::vector<std::string>::const_iterator, it, mDelayedLog)
+            mLogFile << *it;
+        SDL_mutexV(mMutex);
+    }
+}
+
 // here string must be safe for any usage
 void Logger::safeError(const std::string &error_text)
 {
diff --git a/src/logger.h b/src/logger.h
index 0941a0e63..c68277ce5 100644
--- a/src/logger.h
+++ b/src/logger.h
@@ -24,7 +24,11 @@
 #define LOGGER_H
 
 #include "main.h"
+
+#include <SDL_thread.h>
+
 #include <fstream>
+#include <vector>
 
 #include "localconsts.h"
 
@@ -79,6 +83,19 @@ class Logger final
             ;
 
         /**
+         * Enters a message in the log (thread safe).
+         */
+        void log_r(const char *const log_text, ...)
+#ifdef __GNUC__
+#ifdef __OpenBSD__
+            __attribute__((__format__(printf, 2, 3)))
+#else
+            __attribute__((__format__(gnu_printf, 2, 3)))
+#endif
+#endif
+            ;
+
+        /**
          * Enters a message in the log. The message will be timestamped.
          */
         void log1(const char *const log_text);
@@ -88,6 +105,8 @@ class Logger final
          */
         void log(const std::string &str);
 
+        void flush();
+
 #ifdef ENABLEDEBUGLOG
         /**
          * Enters debug message in the log. The message will be timestamped.
@@ -113,6 +132,9 @@ class Logger final
 
     private:
         std::ofstream mLogFile;
+        std::vector<std::string> mDelayedLog;
+        SDL_mutex *mMutex;
+        volatile bool mThreadLocked;
         bool mLogToStandardOut;
         bool mDebugLog;
 };