Unbuffered reading of keystrokes for better latency

ChangeLog

@@ -1,3 +1,7 @@
+2020-03-05  Markus Gans  <guru.mail@muenster.de>
+	* Unbuffered reading of keystrokes for better latency
+	* Mouse adjustments when resizing an rxvt terminal
+
 2020-02-25  Markus Gans  <guru.mail@muenster.de>
 	* New command line switch "--no-terminal-data-request" to disable 
 	  font and title determination

examples/transparent.cpp

@@ -274,6 +274,7 @@ int main (int argc, char* argv[])
 {
   // Create the application object
   finalcut::FApplication app (argc, argv);
+  app.setNonBlockingRead();
 
   // Create main dialog object
   MainWindow main_dlg (&app);

examples/ui.cpp

@@ -1004,6 +1004,7 @@ int main (int argc, char* argv[])
 
   // Create the application object app
   finalcut::FApplication app(argc, argv);
+  app.setNonBlockingRead();
   app.redefineDefaultColors(true);
   app.setTermTitle (title);
 

src/fapplication.cpp

@@ -684,13 +684,11 @@ void FApplication::processKeyboardEvent()
 
   findKeyboardWidget();
   flush();
+  keyboard->escapeKeyHandling();  // special case: Esc key
   keyboard->clearKeyBufferOnTimeout();
 
   if ( isKeyPressed() )
     keyboard->fetchKeyCode();
-
-  // special case: Esc key
-  keyboard->escapeKeyHandling();
 }
 
 //----------------------------------------------------------------------
@@ -1121,6 +1119,12 @@ void FApplication::processResizeEvent()
   if ( ! hasChangedTermSize() )
     return;
 
+  if ( mouse )
+  {
+    mouse->setMaxWidth (uInt16(getDesktopWidth()));
+    mouse->setMaxHeight (uInt16(getDesktopHeight()));
+  }
+
   FResizeEvent r_ev(fc::Resize_Event);
   sendEvent(app_object, &r_ev);
 

src/fkeyboard.cpp

@@ -42,7 +42,8 @@ namespace finalcut
 {
 
 // static class attributes
-uInt64 FKeyboard::key_timeout{100000};  // 100 ms (default timeout for keypress)
+uInt64 FKeyboard::read_blocking_time{100000};  // preset to 100 ms
+uInt64 FKeyboard::key_timeout{100000};         // preset to 100 ms
 struct timeval FKeyboard::time_keypressed{};
 
 #if defined(__linux__)
@@ -123,7 +124,7 @@ bool FKeyboard::isKeyPressed()
   FD_ZERO(&ifds);
   FD_SET(stdin_no, &ifds);
   tv.tv_sec  = 0;
-  tv.tv_usec = 100000;  // 100 ms
+  tv.tv_usec = FKeyboard::read_blocking_time;  // preset to 100 ms
   const int result = select (stdin_no + 1, &ifds, nullptr, nullptr, &tv);
 
   if ( result > 0 && FD_ISSET(stdin_no, &ifds) )
@@ -290,6 +291,7 @@ inline FKey FKeyboard::getSingleKey()
   if ( utf8_input && (firstchar & 0xc0) == 0xc0 )
   {
     char utf8char[5]{};  // Init array with '\0'
+    const std::size_t buf_len = std::strlen(fifo_buf);
 
     if ( (firstchar & 0xe0) == 0xc0 )
       len = 2;
@@ -298,6 +300,9 @@ inline FKey FKeyboard::getSingleKey()
     else if ( (firstchar & 0xf8) == 0xf0 )
       len = 4;
 
+    if ( buf_len <  len && ! isKeypressTimeout() )
+      return fc::need_more_data;
+
     for (std::size_t i{0}; i < len ; i++)
       utf8char[i] = char(fifo_buf[i] & 0xff);
 
@@ -403,7 +408,7 @@ FKey FKeyboard::UTF8decode (const char utf8[])
 inline ssize_t FKeyboard::readKey()
 {
   setNonBlockingInput();
-  const ssize_t bytes = read(FTermios::getStdIn(), &read_buf, READ_BUF_SIZE - 1);
+  const ssize_t bytes = read(FTermios::getStdIn(), &read_character, 1);
   unsetNonBlockingInput();
   return bytes;
 }
@@ -418,12 +423,8 @@ void FKeyboard::parseKeyBuffer()
   {
     if ( bytesread + fifo_offset <= int(FIFO_BUF_SIZE) )
     {
-      for (std::size_t i{0}; i < std::size_t(bytesread); i++)
+      fifo_buf[fifo_offset] = char(read_character);
-      {
+      fifo_offset++;
-        fifo_buf[fifo_offset] = read_buf[i];
-        fifo_offset++;
-      }
-
       fifo_in_use = true;
     }
 
@@ -453,7 +454,7 @@ void FKeyboard::parseKeyBuffer()
     key = 0;
   }
 
-  std::fill_n (read_buf, READ_BUF_SIZE, '\0');
+  read_character = 0;
 }
 
 //----------------------------------------------------------------------

src/fmouse.cpp

@@ -527,7 +527,7 @@ int FMouseGPM::gpmEvent (bool clear)
   FD_SET(stdin_no, &ifds);
   FD_SET(gpm_fd, &ifds);
   tv.tv_sec  = 0;
-  tv.tv_usec = 100000;  // 100 ms
+  tv.tv_usec = FKeyboard::getReadBlockingTime();  // preset to 100 ms
   const int result = select (max + 1, &ifds, nullptr, nullptr, &tv);
 
   if ( result > 0 && FD_ISSET(stdin_no, &ifds) )

src/fvterm.cpp

@@ -182,6 +182,13 @@ FColor FVTerm::rgb2ColorIndex (uInt8 r, uInt8 g, uInt8 b)
   return 16 + ri + gi + bi;
 }
 
+//----------------------------------------------------------------------
+void FVTerm::setNonBlockingRead (bool enable)
+{
+  uInt64 blocking_time = (enable) ? 0 : 100000;  // 0 or 100 ms
+  FKeyboard::setReadBlockingTime (blocking_time); 
+}
+
 //----------------------------------------------------------------------
 void FVTerm::clearArea (int fillchar)
 {

src/fwidget.cpp

@@ -36,7 +36,7 @@ namespace finalcut
 {
 
 // global FWidget object
-static FWidget* rootObject{nullptr};
+static FWidget* root_widget{nullptr};
 
 // static class attributes
 FStatusBar*           FWidget::statusbar{nullptr};
@@ -59,7 +59,7 @@ uInt                  FWidget::modal_dialog_counter{};
 // constructors and destructor
 //----------------------------------------------------------------------
 FWidget::FWidget (FWidget* parent, bool disable_alt_screen)
-  : FVTerm( ! (bool(parent) || rootObject), disable_alt_screen)
+  : FVTerm( ! (bool(parent) || root_widget), disable_alt_screen)
   , FObject(parent)
 {
   // init bit field with 0
@@ -73,7 +73,7 @@ FWidget::FWidget (FWidget* parent, bool disable_alt_screen)
 
   if ( ! parent )
   {
-    if ( rootObject )
+    if ( root_widget )
     {
       auto ftermdata = getFTerm().getFTermData();
       ftermdata->setExitMessage("FWidget: No parent defined! "
@@ -82,12 +82,12 @@ FWidget::FWidget (FWidget* parent, bool disable_alt_screen)
       return;
     }
 
-    rootObject = this;
+    root_widget = this;
     show_root_widget = nullptr;
     redraw_root_widget = nullptr;
     modal_dialog_counter = 0;
     statusbar = nullptr;
-    init();
+    initRootWidget();
   }
   else
   {
@@ -133,7 +133,7 @@ FWidget::~FWidget()  // destructor
   accelerator_list.clear();
 
   // finish the program
-  if ( rootObject == this )
+  if ( root_widget == this )
     finish();
 }
 
@@ -454,7 +454,7 @@ void FWidget::setTopPadding (int top, bool adjust)
   {
     if ( isRootWidget() )
     {
-      auto r = rootObject;
+      auto r = root_widget;
       r->wclient_offset.setY1 (r->padding.top);
       adjustSizeGlobal();
     }
@@ -475,7 +475,7 @@ void FWidget::setLeftPadding (int left, bool adjust)
   {
     if ( isRootWidget() )
     {
-      auto r = rootObject;
+      auto r = root_widget;
       r->wclient_offset.setX1 (r->padding.left);
       adjustSizeGlobal();
     }
@@ -496,7 +496,7 @@ void FWidget::setBottomPadding (int bottom, bool adjust)
   {
     if ( isRootWidget() )
     {
-      auto r = rootObject;
+      auto r = root_widget;
       r->wclient_offset.setY2 (int(r->getHeight()) - 1 - r->padding.bottom);
       adjustSizeGlobal();
     }
@@ -517,7 +517,7 @@ void FWidget::setRightPadding (int right, bool adjust)
   {
     if ( isRootWidget() )
     {
-      auto r = rootObject;
+      auto r = root_widget;
       r->wclient_offset.setX2  (int(r->getWidth()) - 1 - r->padding.right);
       adjustSizeGlobal();
     }
@@ -533,8 +533,8 @@ void FWidget::setTermSize (const FSize& size)
 
   if ( isXTerminal() )
   {
-    rootObject->wsize.setRect(FPoint(1, 1), size);
+    root_widget->wsize.setRect(FPoint(1, 1), size);
-    rootObject->adjust_wsize = rootObject->wsize;
+    root_widget->adjust_wsize = root_widget->wsize;
     FTerm::setTermSize(size);  // width = columns / height = lines
     detectTermSize();
   }
@@ -995,7 +995,7 @@ void FWidget::show()
   {
     // Sets the initial screen settings
     initScreenSettings();
-    // Draw the vdesktop
+    // Initializing vdesktop
     const auto& r = getRootWidget();
     setColor(r->getForegroundColor(), r->getBackgroundColor());
     clearArea (getVirtualDesktop());
@@ -1292,7 +1292,7 @@ void FWidget::adjustSize()
       if ( ignore_padding && ! isDialogWidget() )
         setTermOffset();
       else
-        woffset = rootObject->wclient_offset;
+        woffset = root_widget->wclient_offset;
     }
     else if ( ignore_padding && p )
     {
@@ -1654,8 +1654,8 @@ void FWidget::onAccel (FAccelEvent*)
 void FWidget::onResize (FResizeEvent* ev)
 {
   // The terminal was resized
-  rootObject->resize();
+  root_widget->resize();
-  rootObject->redraw();
+  root_widget->redraw();
   ev->accept();
 }
 
@@ -1676,7 +1676,7 @@ void FWidget::onClose (FCloseEvent* ev)
 
 // private methods of FWidget
 //----------------------------------------------------------------------
-void FWidget::init()
+void FWidget::initRootWidget()
 {
   try
   {
@@ -2012,7 +2012,7 @@ void FWidget::setStatusbarText (bool enable)
 //----------------------------------------------------------------------
 void detectTermSize()
 {
-  const auto& r = rootObject;
+  const auto& r = root_widget;
   FTerm::detectTermSize();
   r->adjust_wsize.setRect (1, 1, r->getDesktopWidth(), r->getDesktopHeight());
   r->woffset.setRect (0, 0, r->getDesktopWidth(), r->getDesktopHeight());

src/fwidget_functions.cpp

@@ -166,7 +166,7 @@ void drawTransparentShadow (FWidget* w)
     w->print() << FPoint(int(width) + 1, int(y) + 1) << "  ";
   }
 
-  w->print() << FStyle (fc::Transparent)
+  w->print() << FStyle (fc::Reset) << FStyle (fc::Transparent)
              << FPoint (1, int(height) + 1)
              << "  "
              << FStyle (fc::Reset)

src/include/final/fkeyboard.h

@@ -104,10 +104,13 @@ class FKeyboard final
     const FString         getKeyName (const FKey);
     keybuffer&            getKeyBuffer();
     timeval*              getKeyPressedTime();
+    static uInt64         getKeypressTimeout();
+    static uInt64         getReadBlockingTime();
 
     // Mutators
     void                  setTermcapMap (fc::FKeyMap*);
-    void                  setKeypressTimeout (const uInt64);
+    static void           setKeypressTimeout (const uInt64);
+    static void           setReadBlockingTime (const uInt64);
     void                  enableUTF8();
     void                  disableUTF8();
     void                  enableMouseSequences();
@@ -130,7 +133,6 @@ class FKeyboard final
 
   private:
     // Constants
-    static constexpr std::size_t READ_BUF_SIZE{1024};
     static constexpr FKey NOT_SET = static_cast<FKey>(-1);
 
     // Accessors
@@ -169,10 +171,11 @@ class FKeyboard final
 #endif
 
     static timeval        time_keypressed;
+    static uInt64         read_blocking_time;
     static uInt64         key_timeout;
     fc::FKeyMap*          key_map{nullptr};
     FKey                  key{0};
-    char                  read_buf[READ_BUF_SIZE]{'\0'};
+    uChar                 read_character{};
     char                  fifo_buf[FIFO_BUF_SIZE]{'\0'};
     int                   fifo_offset{0};
     int                   stdin_status_flags{0};
@@ -200,10 +203,22 @@ inline FKeyboard::keybuffer& FKeyboard::getKeyBuffer()
 inline timeval* FKeyboard::getKeyPressedTime()
 { return &time_keypressed; }
 
+//----------------------------------------------------------------------
+inline uInt64 FKeyboard::getKeypressTimeout()
+{ return key_timeout; }
+
+//----------------------------------------------------------------------
+inline uInt64 FKeyboard::getReadBlockingTime()
+{ return read_blocking_time; }
+
 //----------------------------------------------------------------------
 inline void FKeyboard::setKeypressTimeout (const uInt64 timeout)
 { key_timeout = timeout; }
 
+//----------------------------------------------------------------------
+inline void FKeyboard::setReadBlockingTime (const uInt64 blocking_time)
+{ read_blocking_time = blocking_time; }
+
 //----------------------------------------------------------------------
 inline void FKeyboard::enableUTF8()
 { utf8_input = true; }

src/include/final/fvterm.h

@@ -236,6 +236,10 @@ class FVTerm
     static bool           setInheritBackground();
     static bool           unsetInheritBackground();
 
+    static void           setNonBlockingRead (bool);
+    static void           setNonBlockingRead();
+    static void           unsetNonBlockingRead();
+
     static void           setTermTitle (const FString&);
     static void           setEncoding (fc::encoding);
     static bool           setVGAFont();
@@ -871,6 +875,14 @@ inline bool FVTerm::setInheritBackground()
 inline bool FVTerm::unsetInheritBackground()
 { return setInheritBackground(false); }
 
+//----------------------------------------------------------------------
+inline void FVTerm::setNonBlockingRead()
+{ setNonBlockingRead(true); }
+
+//----------------------------------------------------------------------
+inline void FVTerm::unsetNonBlockingRead()
+{ setNonBlockingRead(false); }
+
 //----------------------------------------------------------------------
 inline void FVTerm::setTermTitle (const FString& title)
 { FTerm::setTermTitle(title); }

src/include/final/fwidget.h

@@ -401,7 +401,7 @@ class FWidget : public FVTerm, public FObject
 
   private:
     // Methods
-    void                    init();
+    void                    initRootWidget();
     void                    finish();
     void                    insufficientSpaceAdjust();
     void                    KeyPressEvent (FKeyEvent*);

test/fkeyboard-test.cpp

@@ -330,6 +330,30 @@ void FKeyboardTest::noArgumentTest()
   keyboard->escapeKeyHandling();
 
   CPPUNIT_ASSERT ( keyboard->getKey() == 0 );
+
+  // Keypress timeout
+  CPPUNIT_ASSERT ( keyboard->getKeypressTimeout() == 100 * 1000 );
+  
+  keyboard->setKeypressTimeout(0);  // 0 ms
+  CPPUNIT_ASSERT ( keyboard->getKeypressTimeout() == 0 );
+
+  keyboard->setKeypressTimeout(100000);  // 100 ms
+  CPPUNIT_ASSERT ( keyboard->getKeypressTimeout() == 100 * 1000 );
+
+  // Read blocking time
+  CPPUNIT_ASSERT ( keyboard->getReadBlockingTime() == 100 * 1000 );
+  
+  keyboard->setReadBlockingTime(1000000);  // 1000 ms
+  CPPUNIT_ASSERT ( keyboard->getReadBlockingTime() == 1000 * 1000 );
+
+  keyboard->setReadBlockingTime(0);  // 0 ms
+  CPPUNIT_ASSERT ( keyboard->getReadBlockingTime() == 0 );
+
+  keyboard->setReadBlockingTime(50000);  // 50 ms
+  CPPUNIT_ASSERT ( keyboard->getReadBlockingTime() == 50 * 1000 );
+
+  keyboard->setReadBlockingTime(100000);  // 100 ms
+  CPPUNIT_ASSERT ( keyboard->getReadBlockingTime() == 100 * 1000 );
 }
 
 //----------------------------------------------------------------------
@@ -2823,13 +2847,11 @@ void FKeyboardTest::input (std::string s)
 //----------------------------------------------------------------------
 void FKeyboardTest::processInput()
 {
+  keyboard->escapeKeyHandling();  // special case: Esc key
   keyboard->clearKeyBufferOnTimeout();
 
   if ( keyboard->isKeyPressed() )
     keyboard->fetchKeyCode();
-
-  // special case: Esc key
-  keyboard->escapeKeyHandling();
 }
 
 //----------------------------------------------------------------------