[Teton] Add a command to print the working directory.

lib/glacier/container/vector.h

@@ -45,6 +45,8 @@ class Vector {
   template <typename... Args>
   void EmplaceBack(Args&&... args);
 
+  T&& PopBack();
+
  private:
   T* data_;
   uint64_t size_;
@@ -119,6 +121,12 @@ void Vector<T>::EmplaceBack(Args&&... args) {
   data_[size_++] = T(args...);
 }
 
+template <typename T>
+T&& Vector<T>::PopBack() {
+  size_--;
+  return glcr::Move(data_[size_]);
+}
+
 template <typename T>
 void Vector<T>::Expand() {
   uint64_t new_capacity = capacity_ == 0 ? 1 : capacity_ * 2;

lib/glacier/string/string_builder.cpp

@@ -19,6 +19,14 @@ void VariableStringBuilder::PushBack(const StringView& str) {
 
 void VariableStringBuilder::PushBack(const char str) { data_.PushBack(str); }
 
+void VariableStringBuilder::DeleteLast() {
+  if (data_.size() > 0) {
+    data_.PopBack();
+  }
+}
+
+void VariableStringBuilder::Reset() { data_ = glcr::Vector<char>(); }
+
 String VariableStringBuilder::ToString() const {
   return String(data_.RawPtr(), size());
 }
@@ -50,4 +58,12 @@ FixedStringBuilder::operator StringView() const {
   return StringView(buffer_, size_);
 }
 
+void FixedStringBuilder::DeleteLast() {
+  if (size_ > 0) {
+    size_--;
+  }
+}
+
+void FixedStringBuilder::Reset() { size_ = 0; }
+
 }  // namespace glcr

lib/glacier/string/string_builder.h

@@ -12,6 +12,9 @@ class StringBuilder {
   virtual void PushBack(const StringView& str) = 0;
   virtual void PushBack(const char str) = 0;
 
+  virtual void DeleteLast() = 0;
+  virtual void Reset() = 0;
+
   virtual String ToString() const = 0;
 
   virtual operator StringView() const = 0;
@@ -30,6 +33,9 @@ class VariableStringBuilder : public StringBuilder {
   virtual void PushBack(const StringView& str) override;
   virtual void PushBack(const char str) override;
 
+  virtual void DeleteLast() override;
+  virtual void Reset() override;
+
   virtual String ToString() const override;
 
   // Note that this could become invalidated
@@ -56,6 +62,9 @@ class FixedStringBuilder : public StringBuilder {
   virtual void PushBack(const StringView& str) override;
   virtual void PushBack(const char str) override;
 
+  virtual void DeleteLast() override;
+  virtual void Reset() override;
+
   virtual String ToString() const override;
 
   virtual operator StringView() const override;

lib/mammoth/input/keyboard.cpp

@@ -102,6 +102,8 @@ void KeyboardListenerBase::HandleKeycode(Keycode code, Action action) {
       c = ' ';
     } else if (code == kTab) {
       c = '\t';
+    } else if (code == kBackspace) {
+      c = '\b';
     } else if (code == kLShift) {
       lshift_ = true;
     } else if (code == kRShift) {

sys/teton/CMakeLists.txt

@@ -2,7 +2,7 @@ add_executable(teton
   framebuffer/console.cpp
   framebuffer/framebuffer.cpp
   framebuffer/psf.cpp
-  keyboard_listener.cpp
+  terminal.cpp
   teton.cpp
   )
 

sys/teton/framebuffer/console.cpp

@@ -7,6 +7,16 @@ void Console::WriteChar(char c) {
     CursorReturn();
     return;
   }
+  if (c == '\t') {
+    WriteString("    ");
+    return;
+  }
+  if (c == '\b') {
+    cursor_pos_--;
+    WriteChar(' ');
+    cursor_pos_--;
+    return;
+  }
 
   uint64_t row = cursor_pos_ / cols();
   if (row >= rows()) {

sys/teton/keyboard_listener.cpp

@@ -1,3 +0,0 @@
-#include "keyboard_listener.h"
-
-void KeyboardListener::HandleCharacter(char c) { console_.WriteChar(c); }

sys/teton/keyboard_listener.h

@@ -1,12 +0,0 @@
-#include <mammoth/input/keyboard.h>
-
-#include "framebuffer/console.h"
-
-class KeyboardListener : public mmth::KeyboardListenerBase {
- public:
-  KeyboardListener(Console& c) : mmth::KeyboardListenerBase(), console_(c) {}
-  virtual void HandleCharacter(char c) override;
-
- private:
-  Console& console_;
-};

sys/teton/terminal.cpp

@@ -0,0 +1,26 @@
+#include "terminal.h"
+
+void Terminal::HandleCharacter(char c) {
+  console_.WriteChar(c);
+  if (c == '\n') {
+    glcr::String str = current_command_.ToString();
+    ExecuteCommand(str);
+    current_command_.Reset();
+  } else if (c == '\b') {
+    current_command_.DeleteLast();
+  } else {
+    current_command_.PushBack(c);
+  }
+}
+
+void Terminal::ExecuteCommand(const glcr::String& command) {
+  if (command == "cwd") {
+    console_.WriteString(cwd_);
+    console_.WriteChar('\n');
+  } else {
+    console_.WriteString("Unknown command: ");
+    console_.WriteString(command);
+    console_.WriteChar('\n');
+  }
+  console_.WriteChar('>');
+}

sys/teton/terminal.h

@@ -0,0 +1,19 @@
+#include <glacier/string/string_builder.h>
+#include <mammoth/input/keyboard.h>
+
+#include "framebuffer/console.h"
+
+class Terminal : public mmth::KeyboardListenerBase {
+ public:
+  Terminal(Console& c) : mmth::KeyboardListenerBase(), console_(c) {}
+
+  virtual void HandleCharacter(char c) override;
+
+  void ExecuteCommand(const glcr::String& command);
+
+ private:
+  Console& console_;
+  glcr::VariableStringBuilder current_command_;
+
+  glcr::String cwd_ = "/";
+};

sys/teton/teton.cpp

@@ -7,7 +7,7 @@
 #include "framebuffer/console.h"
 #include "framebuffer/framebuffer.h"
 #include "framebuffer/psf.h"
-#include "keyboard_listener.h"
+#include "terminal.h"
 
 uint64_t main(uint64_t init_port) {
   ParseInitPort(init_port);
@@ -34,10 +34,10 @@ uint64_t main(uint64_t init_port) {
   Console console(fbuf, psf);
   console.WriteChar('>');
 
-  KeyboardListener listener(console);
-  listener.Register();
+  Terminal terminal(console);
+  terminal.Register();
 
-  Thread lthread = listener.Listen();
+  Thread lthread = terminal.Listen();
 
   check(lthread.Join());