Added log message when frontend unexpectedly loses focus

- hopefully this will help troubleshooting for people who are losing
  focus while running the frontend
- on Windows and Linux the process for the new foreground window will
  be reported in the log

src/fe_util.cpp

@@ -51,6 +51,8 @@
 #include <windows.h>
 #include <io.h>
 #include <fcntl.h>
+#include <tlhelp32.h> // for CreateToolhelp32Snapshot()
+#include <psapi.h> // for GetModuleFileNameEx()
 #else
 #include <sys/wait.h>
 #include <sys/ioctl.h>
@@ -968,10 +970,13 @@ bool run_program( const std::string &prog,
 			FeLog() << "Parameter word expansion failed. [" << args << "]." << std::endl;
 
 		// Provide some debugging output for what we are doing
-		FeDebug() << "execvp(): file='" << prog.c_str() << "', argv=";
-		for ( int r=0; we.we_wordv[r]; r++ )
-			FeDebug() << "[" << we.we_wordv[r] << "]";
-		FeDebug() << std::endl;
+		if ( callback == NULL )
+		{
+			FeDebug() << "execvp(): file='" << prog.c_str() << "', argv=";
+			for ( int r=0; we.we_wordv[r]; r++ )
+				FeDebug() << "[" << we.we_wordv[r] << "]";
+			FeDebug() << std::endl;
+		}
 
 		execvp( prog.c_str(), we.we_wordv );
 
@@ -1352,3 +1357,102 @@ bool get_console_stdin( std::string &str )
 
 	return ( !str.empty() );
 }
+
+std::string get_focus_process()
+{
+	std::string retval( "Unknown" );
+
+#if defined( SFML_SYSTEM_WINDOWS )
+	HWND focus_wnd = GetForegroundWindow();
+	if ( !focus_wnd )
+		return "None";
+
+	DWORD focus_pid( 0 );
+	GetWindowThreadProcessId( focus_wnd, &focus_pid );
+
+	HANDLE snap = CreateToolhelp32Snapshot( TH32CS_SNAPPROCESS, 0 );
+	if ( snap == INVALID_HANDLE_VALUE )
+	{
+		FeLog() << "Could not get process snapshot." << std::endl;
+		return retval;
+	}
+
+	PROCESSENTRY32 pei;
+	pei.dwSize = sizeof( pei );
+	BOOL np = Process32First( snap, &pei );
+	while ( np )
+	{
+		if ( pei.th32ProcessID == focus_pid )
+		{
+			retval = pei.szExeFile;
+			break;
+		}
+		np = Process32Next( snap, &pei );
+	}
+
+	CloseHandle( snap );
+	retval += " (" + as_str( (int)focus_pid ) + ")";
+
+#elif defined( USE_XLIB )
+
+	::Display *xdisp = XOpenDisplay( NULL );
+	Atom atom = XInternAtom( xdisp, "_NET_WM_PID", True );
+
+	Window wnd( 0 );
+	int revert;
+	XGetInputFocus( xdisp, &wnd, &revert );
+	if ( wnd == PointerRoot )
+		return "Pointer Root";
+	else if ( wnd == None )
+		return "None";
+
+	Atom actual_type;
+	int actual_format;
+	unsigned long nitems, bytes_after;
+	unsigned char *prop = NULL;
+
+	if ( XGetWindowProperty( xdisp,
+				wnd,
+				atom,
+				0,
+				1024,
+				False,
+				AnyPropertyType,
+				&actual_type,
+				&actual_format,
+				&nitems,
+				&bytes_after,
+				&prop ) != Success )
+	{
+		FeLog() << "Could not get window property." << std::endl;
+		return retval;
+	}
+
+	if ( !prop )
+	{
+		FeLog() << "Empty window property." << std::endl;
+		return retval;
+	}
+
+	int pid = prop[1] * 256;
+	pid += prop[0];
+	XFree( prop );
+
+	// Try to get the actual name for the process id
+	//
+	// Note: this is Linux specific
+	//
+	std::string fn = "/proc/" + as_str( pid ) + "/cmdline";
+	std::ifstream myfile( fn.c_str() );
+	if ( myfile.good() )
+	{
+		getline( myfile, retval );
+		myfile.close();
+	}
+
+	retval += " (" + as_str( pid ) + ")";
+
+#endif
+
+	return retval;
+}

src/fe_util.hpp

@@ -279,6 +279,9 @@ bool line_to_setting_and_value( const std::string &line,
 	std::string &value,
 	const char *sep=FE_WHITESPACE );
 
+// return the name of the process that currently has window focus
+std::string get_focus_process();
+
 //
 // Non-blocking check for input on stdin
 // return true if input found, false otherwise

src/main.cpp

@@ -122,7 +122,7 @@ int main(int argc, char *argv[])
 	soundsys.play_ambient();
 
 	FeBlend::load_default_shaders();
-	
+
 	FeWindow window( feSettings );
 	window.initial_create();
 
@@ -162,7 +162,7 @@ int main(int argc, char *argv[])
 
 	soundsys.sound_event( FeInputMap::EventStartup );
 
-	bool redraw=true;
+	bool redraw=true, has_focus=true;
 	int guard_joyid=-1, guard_axis=-1;
 
 	// variables used to track movement when a key is held down
@@ -303,6 +303,8 @@ int main(int argc, char *argv[])
 
 				soundsys.sound_event( FeInputMap::EventGameReturn );
 				soundsys.play_ambient();
+
+				has_focus=true;
 			}
 
 			launch_game=false;
@@ -977,6 +979,22 @@ int main(int argc, char *argv[])
 			}
 		}
 
+#if ( SFML_VERSION_INT >= FE_VERSION_INT( 2, 2, 0 ) )
+		//
+		// Log any unexpected loss of window focus
+		//
+		if ( has_focus )
+		{
+			if ( !window.hasFocus() )
+			{
+				has_focus = false;
+				FeLog() << " ! Unexpectedly lost focus to: " << get_focus_process() << std::endl;
+			}
+		}
+		else
+			has_focus = window.hasFocus();
+#endif
+
 		if ( feVM.on_tick() )
 			redraw=true;
 

src/scraper_xml.cpp

@@ -131,7 +131,9 @@ std::string get_crc( const std::string &full_path,
 					return "";
 
 				correct_buff_for_format( buff, size, *itr );
-				return get_crc32( buff, size );
+				std::string retval = get_crc32( buff, size );
+				FeDebug() << "CRC: " << full_path << "=" << retval << std::endl;
+				return retval;
 			}
 		}
 
@@ -165,6 +167,7 @@ std::string get_crc( const std::string &full_path,
 
 	delete [] orig_buff_ptr;
 
+	FeDebug() << "CRC: " << full_path << "=" << retval << std::endl;
 	return retval;
 }