LibVT: Move most of key press handling logic into VT::Terminal

This will let us share it between the userspace (TerminalWidget) and the Kernel.

Author: bugaevc

Libraries/LibVT/Terminal.cpp

@@ -25,6 +25,7 @@
  */
 
 #include <AK/StringBuilder.h>
+#include <AK/StringView.h>
 #include <LibVT/Terminal.h>
 #include <string.h>
 
@@ -1004,6 +1005,69 @@ void Terminal::emit_string(const StringView& string)
     m_client.emit((const u8*)string.characters_without_null_termination(), string.length());
 }
 
+void Terminal::handle_key_press(KeyCode key, u8 character, u8 flags)
+{
+    bool ctrl = flags & Mod_Ctrl;
+    bool alt = flags & Mod_Alt;
+    bool shift = flags & Mod_Shift;
+
+    switch (key) {
+    case KeyCode::Key_Up:
+        emit_string(ctrl ? "\033[OA" : "\033[A");
+        return;
+    case KeyCode::Key_Down:
+        emit_string(ctrl ? "\033[OB" : "\033[B");
+        return;
+    case KeyCode::Key_Right:
+        emit_string(ctrl ? "\033[OC" : "\033[C");
+        return;
+    case KeyCode::Key_Left:
+        emit_string(ctrl ? "\033[OD" : "\033[D");
+        return;
+    case KeyCode::Key_Insert:
+        emit_string("\033[2~");
+        return;
+    case KeyCode::Key_Delete:
+        emit_string("\033[3~");
+        return;
+    case KeyCode::Key_Home:
+        emit_string("\033[H");
+        return;
+    case KeyCode::Key_End:
+        emit_string("\033[F");
+        return;
+    case KeyCode::Key_PageUp:
+        emit_string("\033[5~");
+        return;
+    case KeyCode::Key_PageDown:
+        emit_string("\033[6~");
+        return;
+    default:
+        break;
+    }
+
+    if (shift && key == KeyCode::Key_Tab) {
+        emit_string("\033[Z");
+        return;
+    }
+
+    // Key event was not one of the above special cases,
+    // attempt to treat it as a character...
+    if (ctrl) {
+        if (character >= 'a' && character <= 'z') {
+            character = character - 'a' + 1;
+        } else if (character == '\\') {
+            character = 0x1c;
+        }
+    }
+
+    // Alt modifier sends escape prefix.
+    if (alt)
+        emit_string("\033");
+
+    emit_string({ &character, 1 });
+}
+
 void Terminal::unimplemented_escape()
 {
     StringBuilder builder;

Libraries/LibVT/Terminal.h

@@ -30,6 +30,7 @@
 #include <AK/NonnullOwnPtrVector.h>
 #include <AK/String.h>
 #include <AK/Vector.h>
+#include <Kernel/KeyCode.h>
 #include <LibVT/Line.h>
 #include <LibVT/Position.h>
 
@@ -95,6 +96,7 @@ class Terminal {
     const NonnullOwnPtrVector<Line>& history() const { return m_history; }
 
     void inject_string(const StringView&);
+    void handle_key_press(KeyCode, u8 charatcter, u8 flags);
 
     Attribute attribute_at(const Position&) const;
 

Libraries/LibVT/TerminalWidget.cpp

@@ -206,90 +206,38 @@ void TerminalWidget::keydown_event(GUI::KeyEvent& event)
     m_cursor_blink_timer->stop();
     m_cursor_blink_state = true;
     m_cursor_blink_timer->start();
-    auto ctrl_held = !!(event.modifiers() & Mod_Ctrl);
 
-    switch (event.key()) {
-    case KeyCode::Key_Up:
-        write(m_ptm_fd, ctrl_held ? "\033[OA" : "\033[A", 3 + ctrl_held);
-        return;
-    case KeyCode::Key_Down:
-        write(m_ptm_fd, ctrl_held ? "\033[OB" : "\033[B", 3 + ctrl_held);
-        return;
-    case KeyCode::Key_Right:
-        write(m_ptm_fd, ctrl_held ? "\033[OC" : "\033[C", 3 + ctrl_held);
-        return;
-    case KeyCode::Key_Left:
-        write(m_ptm_fd, ctrl_held ? "\033[OD" : "\033[D", 3 + ctrl_held);
-        return;
-    case KeyCode::Key_Insert:
-        write(m_ptm_fd, "\033[2~", 4);
+    if (event.key() == KeyCode::Key_PageUp && event.modifiers() == Mod_Shift) {
+        m_scrollbar->set_value(m_scrollbar->value() - m_terminal.rows());
         return;
-    case KeyCode::Key_Delete:
-        write(m_ptm_fd, "\033[3~", 4);
-        return;
-    case KeyCode::Key_Home:
-        write(m_ptm_fd, "\033[H", 3);
-        return;
-    case KeyCode::Key_End:
-        write(m_ptm_fd, "\033[F", 3);
-        return;
-    case KeyCode::Key_PageUp:
-        if (event.modifiers() == Mod_Shift) {
-            m_scrollbar->set_value(m_scrollbar->value() - m_terminal.rows());
-            return;
-        }
-        write(m_ptm_fd, "\033[5~", 4);
-        return;
-    case KeyCode::Key_PageDown:
-        if (event.modifiers() == Mod_Shift) {
-            m_scrollbar->set_value(m_scrollbar->value() + m_terminal.rows());
-            return;
-        }
-        write(m_ptm_fd, "\033[6~", 4);
-        return;
-    case KeyCode::Key_Alt:
-        m_alt_key_held = true;
+    }
+    if (event.key() == KeyCode::Key_PageDown && event.modifiers() == Mod_Shift) {
+        m_scrollbar->set_value(m_scrollbar->value() + m_terminal.rows());
         return;
-    default:
-        break;
     }
-
-    if (event.shift() && event.key() == KeyCode::Key_Tab) {
-        write(m_ptm_fd, "\033[Z", 3);
+    if (event.key() == KeyCode::Key_Alt) {
+        m_alt_key_held = true;
         return;
     }
 
-    // Key event was not one of the above special cases,
-    // attempt to treat it as a character...
-    if (event.text().length() == 1) {
-        // 1 byte input == ASCII
-        char ch = !event.text().is_empty() ? event.text()[0] : 0;
-        if (event.ctrl()) {
-            if (ch >= 'a' && ch <= 'z') {
-                ch = ch - 'a' + 1;
-            } else if (ch == '\\') {
-                ch = 0x1c;
-            }
-        }
-
-        // ALT modifier sends escape prefix
-        if (event.alt())
-            write(m_ptm_fd, "\033", 1);
-
-        //Clear the selection if we type in/behind it
-        auto future_cursor_column = (event.key() == KeyCode::Key_Backspace) ? m_terminal.cursor_column() - 1 : m_terminal.cursor_column();
-        auto min_selection_row = min(m_selection_start.row(), m_selection_end.row());
-        auto max_selection_row = max(m_selection_start.row(), m_selection_end.row());
+    // Clear the selection if we type in/behind it.
+    auto future_cursor_column = (event.key() == KeyCode::Key_Backspace) ? m_terminal.cursor_column() - 1 : m_terminal.cursor_column();
+    auto min_selection_row = min(m_selection_start.row(), m_selection_end.row());
+    auto max_selection_row = max(m_selection_start.row(), m_selection_end.row());
 
-        if (future_cursor_column <= last_selection_column_on_row(m_terminal.cursor_row()) && m_terminal.cursor_row() >= min_selection_row && m_terminal.cursor_row() <= max_selection_row) {
-            m_selection_end = {};
-            update();
-        }
+    if (future_cursor_column <= last_selection_column_on_row(m_terminal.cursor_row()) && m_terminal.cursor_row() >= min_selection_row && m_terminal.cursor_row() <= max_selection_row) {
+        m_selection_end = {};
+        update();
+    }
 
-        write(m_ptm_fd, &ch, 1);
-    } else if (event.text().length() > 1) {
-        // 2+ byte input == Unicode
+    if (event.text().length() > 2) {
+        // Unicode (likely emoji), just emit it.
         write(m_ptm_fd, event.text().characters(), event.text().length());
+    } else {
+        // Ask the terminal to generate the correct character sequence and send
+        // it back to us via emit().
+        u8 character = event.text().length() == 1 ? event.text()[0] : 0;
+        m_terminal.handle_key_press(event.key(), character, event.modifiers());
     }
 
     if (event.key() != Key_Control && event.key() != Key_Alt && event.key() != Key_Shift && event.key() != Key_Logo)