Rage hacking on TerminalWidget.

There's some really hideous plumbing with globals going on here, but my
priority right now is getting a basic VT100 terminal emulator working.

Widgets/AbstractScreen.cpp

@@ -3,9 +3,12 @@
 #include "Event.h"
 #include "Widget.h"
 #include <AK/Assertions.h>
+#include "TerminalWidget.h"
 
 static AbstractScreen* s_the;
 
+extern TerminalWidget* g_tw;
+
 AbstractScreen& AbstractScreen::the()
 {
     ASSERT(s_the);
@@ -36,7 +39,16 @@ void AbstractScreen::event(Event& event)
         //printf("hit test for %d,%d found: %s{%p} %d,%d\n", me.x(), me.y(), result.widget->className(), result.widget, result.localX, result.localY);
         auto localEvent = make<MouseEvent>(event.type(), result.localX, result.localY, me.button());
         result.widget->event(*localEvent);
+        return Object::event(event);
     }
+
+    if (event.type() == Event::KeyDown || event.type() == Event::KeyUp) {
+        // FIXME: Implement proper focus.
+        Widget* focusedWidget = g_tw;
+        return focusedWidget->event(event);
+    }
+
+    return Object::event(event);
 }
 
 void AbstractScreen::setRootWidget(Widget* widget)

Widgets/EventLoopSDL.cpp

@@ -3,6 +3,11 @@
 #include <SDL.h>
 #include "AbstractScreen.h"
 #include "Widget.h"
+#include "TerminalWidget.h"
+#include <unistd.h>
+
+int g_fd;
+extern TerminalWidget* g_tw;
 
 EventLoopSDL::EventLoopSDL()
 {
@@ -14,7 +19,6 @@ EventLoopSDL::~EventLoopSDL()
 
 static inline MouseButton toMouseButton(byte sdlButton)
 {
-    printf("sdlbutton = %u\n", sdlButton);
     if (sdlButton == 1)
         return MouseButton::Left;
     if (sdlButton == 2)
@@ -25,10 +29,15 @@ static inline MouseButton toMouseButton(byte sdlButton)
     return MouseButton::None;
 }
 
+static inline int toKey(const SDL_Keysym& sym)
+{
+    return sym.sym;
+}
+
 void EventLoopSDL::waitForEvent()
 {
     SDL_Event sdlEvent;
-    while (SDL_WaitEvent(&sdlEvent) != 0) {
+    while (SDL_PollEvent(&sdlEvent) != 0) {
         switch (sdlEvent.type) {
         case SDL_QUIT:
             postEvent(nullptr, make<QuitEvent>());
@@ -49,7 +58,28 @@ void EventLoopSDL::waitForEvent()
         case SDL_MOUSEBUTTONUP:
             postEvent(&AbstractScreen::the(), make<MouseEvent>(Event::MouseUp, sdlEvent.button.x, sdlEvent.button.y, toMouseButton(sdlEvent.button.button)));
             return;
+        case SDL_KEYDOWN:
+            postEvent(&AbstractScreen::the(), make<KeyEvent>(Event::KeyDown, toKey(sdlEvent.key.keysym)));
+            return;
+        case SDL_KEYUP:
+            postEvent(&AbstractScreen::the(), make<KeyEvent>(Event::KeyUp, toKey(sdlEvent.key.keysym)));
+            return;
         }
     }
+
+    fd_set rfds;
+    FD_ZERO(&rfds);
+    FD_SET(g_fd, &rfds);
+
+    struct timeval tv = { 0, 5000 };
+    int rc = select(g_fd + 1, &rfds, NULL, NULL, &tv);
+
+    //printf("select{%d} = %d\n", g_fd, rc);
+
+    if (rc > 0) {
+        byte buf[1024];
+        int nread = read(g_fd, buf, sizeof(buf));
+        g_tw->onReceive(ByteBuffer::wrap(buf, nread));
+    }
 }
 

Widgets/Painter.cpp

@@ -55,9 +55,14 @@ void Painter::drawText(const Rect& rect, const String& text, TextAlignment align
         int y = point.y() + row;
         dword* bits = scanline(y);
         for (unsigned i = 0; i < text.length(); ++i) {
-            if (text[i] == ' ')
+            byte ch = text[i];
+            if (ch == ' ')
                 continue;
-            const char* fontCharacter = Peanut8x8::font[text[i] - Peanut8x8::firstCharacter];
+            if (ch < Peanut8x8::firstCharacter || ch > Peanut8x8::lastCharacter) {
+                printf("Font doesn't have 0x%02x ('%c')\n", ch, ch);
+                ASSERT_NOT_REACHED();
+            }
+            const char* fontCharacter = Peanut8x8::font[ch - Peanut8x8::firstCharacter];
             int x = point.x() + i * Peanut8x8::fontWidth;
             for (unsigned j = 0; j < Peanut8x8::fontWidth; ++j) {
                 char fc = fontCharacter[row * Peanut8x8::fontWidth + j];

Widgets/Peanut8x8.h

@@ -3,6 +3,7 @@
 namespace Peanut8x8 {
 
 static constexpr char firstCharacter = '!';
+static constexpr char lastCharacter = '~';
 static constexpr byte fontWidth = 8;
 static constexpr byte fontHeight = 8;
 

Widgets/TerminalWidget.cpp

@@ -1,18 +1,47 @@
 #include "TerminalWidget.h"
 #include "Painter.h"
+#include <unistd.h>
+#include <signal.h>
+#include <sys/ioctl.h>
+#include <fcntl.h>
+
+extern int g_fd;
+TerminalWidget* g_tw;
 
 TerminalWidget::TerminalWidget(Widget* parent)
     : Widget(parent)
 {
+    g_tw = this;
+    
     setRect({ 100, 300, columns() * 8, rows() * 8 });
-    m_screen = new CharacterWithAttributes[rows() * columns() * 2]; 
+    printf("rekt: %d x %d\n", width(), height());
+    m_screen = new CharacterWithAttributes[rows() * columns()]; 
     for (unsigned row = 0; row < m_rows; ++row) {
         for (unsigned column = 0; column < m_columns; ++column) {
             at(row, column).character = ' ';
             at(row, column).attribute = 0x07;
         }
     }
-    onReceive(String("Serenity/OS").toByteBuffer());
+    g_fd = getpt();
+    grantpt(g_fd);
+    unlockpt(g_fd);
+    char buf[1024];
+    ptsname_r(g_fd, buf, sizeof(buf));
+
+    if (fork() == 0) {
+        close(g_fd);
+        setsid();
+        int fd = open(buf, O_RDWR);
+        dup2(fd, 0);
+        dup2(fd, 1);
+        dup2(fd, 2);
+        signal(SIGWINCH, SIG_IGN);
+        ioctl(fd, TIOCSCTTY);
+        execl("/bin/bash", "bash", nullptr);
+        ASSERT_NOT_REACHED();
+    }
+
+    signal(SIGCHLD, SIG_IGN);
 }
 
 TerminalWidget::~TerminalWidget()
@@ -53,17 +82,52 @@ void TerminalWidget::onReceive(const ByteBuffer& buffer)
 
 void TerminalWidget::onReceive(byte ch)
 {
-    at(m_cursorRow, m_cursorColumn).character = ch;
+    //printf("receive %02x\n", ch);
-    printf("%2u,%2u -> ", m_cursorRow, m_cursorColumn);
+    auto scrollScreen = [&] () {
-    if (++m_cursorColumn > m_columns) {
+        memmove(m_screen, m_screen + columns(), (m_rows - 1) * columns() * sizeof(CharacterWithAttributes));
-        m_cursorColumn = 0;
+        memset(m_screen + (m_rows - 1) * columns(), ' ', columns() * sizeof(CharacterWithAttributes) * 2);
+    };
+
+    auto addChar = [&] (byte ch) {
+        at(m_cursorRow, m_cursorColumn).character = ch;
+        if (++m_cursorColumn > m_columns) {
+            m_cursorColumn = 0;
+            if (m_cursorRow < (m_rows - 1)) {
+                ++m_cursorRow;
+            } else {
+                scrollScreen();
+            }
+        }
+    };
+
+    if (ch == '\n') {
         if (m_cursorRow < (m_rows - 1)) {
             ++m_cursorRow;
         } else {
-            // FIXME: Scroll it!
+            scrollScreen();
-            ASSERT_NOT_REACHED();
         }
+    } else if (ch == '\r') {
+        m_cursorColumn = 0;
+    } else if (ch == '\t') {
+        while ((m_cursorColumn % 8) != 0 && m_cursorColumn < m_columns) {
+            addChar(' ');
+        }
+    } else {
+        addChar(ch);
     }
-    printf("%2u,%2u\n", m_cursorRow, m_cursorColumn);
+    update();
+}
+
+void TerminalWidget::onKeyDown(KeyEvent& event)
+{
+    char buf[] = { 0, 0 };
+    buf[0] = event.key();
+    write(g_fd, buf, 2);
+    return Widget::onKeyDown(event);
+}
+
+void TerminalWidget::onKeyUp(KeyEvent& event)
+{
+    return Widget::onKeyUp(event);
 }
 

Widgets/TerminalWidget.h

@@ -15,13 +15,16 @@ public:
 
     unsigned rows() const { return m_rows; }
     unsigned columns() const { return m_columns; }
+
+    void onReceive(const ByteBuffer&);
+    void onReceive(byte);
     
 private:
     CharacterWithAttributes& at(unsigned row, unsigned column);
 
     virtual void onPaint(PaintEvent&) override;
-    void onReceive(const ByteBuffer&);
+    virtual void onKeyDown(KeyEvent&) override;
-    void onReceive(byte);
+    virtual void onKeyUp(KeyEvent&) override;
 
     unsigned m_columns { 80 };
     unsigned m_rows { 25 };

Widgets/Widget.cpp

@@ -25,6 +25,7 @@ void Widget::event(Event& event)
 {
     switch (event.type()) {
     case Event::Paint:
+        m_hasPendingPaintEvent = false;
         return onPaint(static_cast<PaintEvent&>(event));
     case Event::Show:
         return onShow(static_cast<ShowEvent&>(event));
@@ -85,6 +86,9 @@ void Widget::onMouseMove(MouseEvent&)
 
 void Widget::update()
 {
+    if (m_hasPendingPaintEvent)
+        return;
+    m_hasPendingPaintEvent = true;
     EventLoop::main().postEvent(this, make<PaintEvent>());
 }
 

Widgets/Widget.h

@@ -49,4 +49,6 @@ private:
     Rect m_rect;
     Color m_backgroundColor;
     Color m_foregroundColor;
+
+    bool m_hasPendingPaintEvent { false };
 };