[Android] Redirect error messages to logcat by default

src/SFML/Main/MainAndroid.cpp

@@ -42,6 +42,7 @@
 #include <SFML/System/Sleep.hpp>
 #include <SFML/System/Thread.hpp>
 #include <SFML/System/Lock.hpp>
+#include <SFML/System/Err.hpp>
 #include <android/window.h>
 #include <android/native_activity.h>
 
@@ -485,6 +486,9 @@ void ANativeActivity_onCreate(ANativeActivity* activity, void* savedState, size_
 
     getScreenSizeInPixels(activity, &states->screenSize.x, &states->screenSize.y);
 
+    // Redirect error messages to logcat
+    sf::err().rdbuf(&states->logcat);
+
     // Launch the main thread
     sf::Thread* thread = new sf::Thread(sf::priv::main, states);
     thread->launch();

src/SFML/System/Android/Activity.cpp

@@ -28,6 +28,29 @@
 // Headers
 ////////////////////////////////////////////////////////////
 #include <SFML/System/Android/Activity.hpp>
+#include <android/log.h>
+
+#define LOGE(...) ((void)__android_log_print(ANDROID_LOG_INFO, "sfml-error", __VA_ARGS__))
+
+LogcatStream::LogcatStream() :
+std::streambuf()
+{
+    // Nothing to do
+}
+
+std::streambuf::int_type LogcatStream::overflow (std::streambuf::int_type c)
+{
+    if (c == "\n"[0])
+    {
+        m_message.push_back(c);
+        LOGE(m_message.c_str());
+        m_message.clear();
+    }
+
+    m_message.push_back(c);
+
+    return traits_type::not_eof(c);
+}
 
 namespace sf
 {

src/SFML/System/Android/Activity.hpp

@@ -36,7 +36,19 @@
 #include <EGL/egl.h>
 #include <vector>
 #include <map>
+#include <string>
+#include <fstream>
 
+class SFML_SYSTEM_API LogcatStream : public std::streambuf
+{
+public:
+    LogcatStream();
+
+    std::streambuf::int_type overflow (std::streambuf::int_type c);
+
+private:
+    std::string m_message;
+};
 
 namespace sf
 {
@@ -76,6 +88,8 @@ struct ActivityStates
     bool fullscreen;
 
     bool updated;
+
+    LogcatStream logcat;
 };
 
 SFML_SYSTEM_API ActivityStates* getActivity(ActivityStates* initializedStates=NULL, bool reset=false);

src/SFML/System/CMakeLists.txt

@@ -90,7 +90,7 @@ if(SFML_OS_WINDOWS)
     list(APPEND SYSTEM_EXT_LIBS winmm)
 endif()
 if(SFML_OS_ANDROID)
-    list(APPEND SYSTEM_EXT_LIBS android)
+    list(APPEND SYSTEM_EXT_LIBS android log)
 endif()
 
 # define the sfml-system target