keyboard input buffering

7 files changed, 681 insertions, 52 deletions

diff --git a/Makefile b/Makefile
index f3674a6..0480943 100644
--- a/Makefile
+++ b/Makefile
@@ -1,5 +1,5 @@
-CXXFLAGS := -m32 -ggdb -g3 -O0 -fno-pic -ffreestanding -fno-rtti -fno-exceptions -std=c++23
-LDFLAGS := -m32 -static -T link.ld -ffreestanding -nostdlib
+CXXFLAGS := -m32 -ggdb -g3 -O0 -fno-pic -fno-rtti -fno-exceptions -std=c++23
+LDFLAGS := $(CXXFLAGS) -T link.ld -static -nostdlib -fno-use-cxa-atexit
 
 CXXFILES := acpi.cpp \
         boot.cpp \
diff --git a/circularbuffer.hpp b/circularbuffer.hpp
new file mode 100644
index 0000000..64a9e48
--- /dev/null
+++ b/circularbuffer.hpp
@@ -0,0 +1,573 @@
+/*
+MIT License
+
+Copyright (c) 2020 Vinit James
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+SOFTWARE.
+*/
+
+#ifndef CIRCULAR_BUFFER_H
+#define CIRCULAR_BUFFER_H
+
+#include <algorithm>
+#include <iterator>
+#include <mutex>
+#include <memory>
+#include <stdexcept>
+#include <utility>
+
+
+template<typename T>
+class CircularBuffer {
+private:
+	
+	typedef T* pointer;
+	typedef const T* const_pointer;
+	typedef T& reference;
+	typedef const T& const_reference;
+	typedef size_t size_type;
+	typedef ptrdiff_t difference_type;
+    template <bool isConst> struct BufferIterator;
+	
+
+public:
+    typedef T value_type;
+
+    // clyne
+    constexpr CircularBuffer()
+        :_buff{}, _max_size{0} {}
+
+	explicit CircularBuffer(size_t size)
+		:_buff{std::unique_ptr<T[]>(new value_type[size])}, _max_size{size}{}
+
+	CircularBuffer(const CircularBuffer& other)
+		:_buff{std::unique_ptr<T[]>(new value_type[other._max_size])},
+		 _max_size{other._max_size},
+		 _size{other._size},
+		 _head{other._head},
+		 _tail{other._tail}{
+			 std::copy(other.data(), other.data() + _max_size, _buff.get());
+		 }
+
+	
+	CircularBuffer& operator=(const CircularBuffer& other){
+		if ( this != &other){
+			_buff.reset(new value_type[other._max_size]);
+			_max_size = other._max_size;
+			_size = other._size;
+			_head = other._head;
+			_tail = other._tail;
+			std::copy(other.data(), other.data() + _max_size, _buff.get());
+		}
+		return *this;
+	}
+
+	CircularBuffer(CircularBuffer&& other) noexcept
+		:_buff{std::move(other._buff)},
+		 _max_size{other._max_size},
+		 _size{other._size},
+		 _head{other._head},
+		 _tail{other._tail}{
+
+		other._buff = nullptr;
+		other._max_size = 0;
+		other._size = 0;
+		other._head = 0;
+		other._tail = 0;
+	}
+
+	
+	CircularBuffer& operator=(CircularBuffer&& other) noexcept{
+		if ( this != &other){
+			_buff = std::move(other._buff);
+			_max_size = other._max_size;
+			_size = other._size;
+			_head = other._head;
+			_tail = other._tail;
+			
+			other._buff = nullptr;
+			other._max_size = 0;
+			other._size = 0;
+			other._head = 0;
+			other._tail = 0;			
+		}
+		return *this;
+	}
+	
+	void push_back(const value_type& data);
+	void push_back(value_type&& data) noexcept;
+	void pop_front();
+	reference front();
+	reference back(); 
+	const_reference front() const; 
+	const_reference back() const;
+	void clear();
+	bool empty() const ;
+	bool full() const ;
+	size_type capacity() const ;
+	size_type size() const;
+	size_type buffer_size() const {return sizeof(value_type)*_max_size;};
+	const_pointer data() const { return _buff.get(); }
+	
+	const_reference operator[](size_type index) const;
+	reference operator[](size_type index);
+	const_reference at(size_type index) const;
+	reference at(size_type index);
+
+	typedef BufferIterator<false> iterator;
+	typedef BufferIterator<true> const_iterator;
+	
+	iterator begin();
+	const_iterator begin() const;
+	iterator end();
+	const_iterator end() const;
+	const_iterator cbegin() const noexcept;
+	const_iterator cend() const noexcept;
+	iterator rbegin() noexcept;
+	const_iterator rbegin() const noexcept;
+	iterator rend() noexcept;
+	const_iterator rend() const noexcept;
+	
+		
+private:
+	void _increment_bufferstate();
+	void _decrement_bufferstate();
+    // clyne
+	//mutable std::mutex _mtx;
+	std::unique_ptr<value_type[]> _buff;
+	size_type _head = 0;
+	size_type _tail = 0;
+	size_type _size = 0;
+	size_type _max_size = 0;
+			
+    template<bool isConst = false>
+	struct  BufferIterator{
+	public:
+		friend class CircularBuffer<T>;
+		typedef std::random_access_iterator_tag iterator_category;
+		typedef ptrdiff_t difference_type;
+		typedef T value_type;
+		typedef typename std::conditional<isConst, const value_type&, value_type&>::type reference;
+		typedef typename std::conditional<isConst, const value_type*, value_type*>::type pointer;
+		typedef typename std::conditional<isConst, const CircularBuffer<value_type>*,
+										  CircularBuffer<value_type>*>::type cbuf_pointer;
+	private:
+		cbuf_pointer _ptrToBuffer;
+		size_type _offset;
+		size_type _index;
+		bool _reverse;
+		
+		bool _comparable(const BufferIterator<isConst>& other) const{
+			return (_ptrToBuffer == other._ptrToBuffer)&&(_reverse == other._reverse);
+		}
+		
+	public:
+		BufferIterator()
+			:_ptrToBuffer{nullptr}, _offset{0}, _index{0}, _reverse{false}{}
+		
+		BufferIterator(const BufferIterator<false>& it)
+			:_ptrToBuffer{it._ptrToBuffer},
+			 _offset{it._offset},
+			 _index{it._index},
+			 _reverse{it._reverse}{}
+
+		reference operator*(){
+			if(_reverse)
+				return (*_ptrToBuffer)[(_ptrToBuffer->size() - _index - 1)];
+			return (*_ptrToBuffer)[_index];
+		}
+
+		pointer  operator->() { return &(operator*()); }
+
+		reference operator[](size_type index){
+			BufferIterator iter = *this;
+			iter._index += index;
+			return *iter;
+		}
+
+		BufferIterator& operator++(){
+			++_index;
+			return *this;
+		}
+
+		BufferIterator operator++(int){
+			BufferIterator iter = *this;
+			++_index;
+			return iter;
+		}
+
+		BufferIterator& operator--(){
+			--_index;
+			return *this;
+		}
+
+		BufferIterator operator--(int){
+			BufferIterator iter = *this;
+			--_index;
+			return iter;
+		}	
+
+		friend BufferIterator operator+(BufferIterator lhsiter, difference_type n){
+			lhsiter._index += n;
+			return lhsiter;
+		}
+
+		friend BufferIterator operator+(difference_type n, BufferIterator rhsiter){
+			rhsiter._index += n;
+			return rhsiter;
+		}
+		
+
+		BufferIterator& operator+=(difference_type n){
+			_index += n;
+			return *this;
+		}
+
+		friend BufferIterator operator-(BufferIterator lhsiter, difference_type n){
+			lhsiter._index -= n;
+			return lhsiter;
+		}
+
+		friend difference_type operator-(const BufferIterator& lhsiter, const BufferIterator& rhsiter){
+			
+			return lhsiter._index - rhsiter._index;
+		}
+
+		BufferIterator& operator-=(difference_type n){
+			_index -= n;
+			return *this;
+		}
+
+		bool operator==(const BufferIterator& other) const{
+			if (!_comparable(other))
+				return false;
+			return ((_index == other._index)&&(_offset == other._offset));
+		}
+		
+		bool operator!=(const BufferIterator& other) const{
+			if (!_comparable(other))
+				return true;
+			return ((_index != other._index)||(_offset != other._offset));
+		}
+
+		bool operator<(const BufferIterator& other) const {
+			if (!_comparable(other))
+				return false;
+			return ((_index + _offset)<(other._index+other._offset));
+		}
+
+		bool operator>(const BufferIterator& other) const{
+			if (!_comparable(other))
+				return false;
+			return ((_index + _offset)>(other._index+other._offset));
+		}
+
+		bool operator<=(const BufferIterator& other) const {
+			if (!_comparable(other))
+				return false;
+			return ((_index + _offset)<=(other._index+other._offset));
+		}
+
+		bool operator>=(const BufferIterator& other) const {
+			if (!_comparable(other))
+				return false;
+			return ((_index + _offset)>=(other._index+other._offset));
+		}
+	};
+};
+
+template<typename T>
+inline 
+bool CircularBuffer<T>::full() const{
+	return _size == _max_size;
+}
+
+template<typename T>
+inline 
+bool CircularBuffer<T>::empty() const{
+	return _size == 0;
+}
+
+template<typename T>
+inline 
+typename CircularBuffer<T>::size_type CircularBuffer<T>::capacity() const{
+	return _max_size;
+}
+
+template<typename T>
+inline 
+void  CircularBuffer<T>::clear(){
+	//std::lock_guard<std::mutex> _lck(_mtx);
+	_head = _tail = _size = 0;
+}
+
+template<typename T>
+inline 
+typename CircularBuffer<T>::size_type CircularBuffer<T>::size() const{
+	//std::lock_guard<std::mutex> _lck(_mtx);
+	return _size;
+	}
+
+template<typename T>
+inline
+typename CircularBuffer<T>::reference CircularBuffer<T>::front() {
+	//std::lock_guard<std::mutex> _lck(_mtx);
+    // clyne
+	if(empty())
+		abort(); //throw std::length_error("front function called on empty buffer");
+	return _buff[_tail];
+}
+
+template<typename T>
+inline
+typename CircularBuffer<T>::reference CircularBuffer<T>::back() {
+	//std::lock_guard<std::mutex> _lck(_mtx);
+	if(empty())
+		abort(); //throw std::length_error("back function called on empty buffer");
+	return _head == 0 ? _buff[_max_size - 1] : _buff[_head - 1];
+}
+
+template<typename T>
+inline
+typename CircularBuffer<T>::const_reference CircularBuffer<T>::front() const{
+	//std::lock_guard<std::mutex> _lck(_mtx);
+	if(empty())
+		abort(); //throw std::length_error("front function called on empty buffer");
+	return _buff[_tail];
+}
+
+template<typename T>
+inline
+typename CircularBuffer<T>::const_reference CircularBuffer<T>::back() const{
+	//std::lock_guard<std::mutex> _lck(_mtx);
+	if(empty())
+		abort(); //throw std::length_error("back function called on empty buffer");
+	return _head == 0 ? _buff[_max_size - 1] : _buff[_head - 1];
+}
+
+template<typename T>
+inline
+void CircularBuffer<T>::push_back(const T& data){
+	//std::lock_guard<std::mutex> _lck(_mtx);
+	//if(full())
+	//	_buff[_tail].~T();
+	_buff[_head] = data;
+	_increment_bufferstate();
+}
+
+template<typename T>
+inline
+void CircularBuffer<T>::push_back(T&& data) noexcept{
+	//std::lock_guard<std::mutex> _lck(_mtx);
+	_buff[_head] = std::move(data);
+	_increment_bufferstate();
+}
+
+
+template<typename T>
+inline 
+void CircularBuffer<T>::_increment_bufferstate(){
+	if(full())
+		_tail = (_tail + 1)%_max_size;
+	else
+		++_size;
+	_head = (_head + 1)%_max_size;	
+}
+
+template<typename T>
+inline 
+void CircularBuffer<T>::pop_front(){
+	//std::lock_guard<std::mutex> _lck(_mtx);
+	if(empty())
+		abort(); //throw std::length_error("pop_front called on empty buffer");
+	_decrement_bufferstate();
+}
+
+template<typename T>
+inline 
+void CircularBuffer<T>::_decrement_bufferstate(){
+	--_size;
+	_tail = (_tail + 1)%_max_size;
+}
+
+template<typename T>
+inline 
+typename CircularBuffer<T>::reference CircularBuffer<T>::operator[](size_t index) {
+	//std::lock_guard<std::mutex> _lck(_mtx);
+	if((index<0)||(index>=_size))
+		abort(); //throw std::out_of_range("Index is out of Range of buffer size");
+	index += _tail;
+	index %= _max_size;
+	return _buff[index];
+}
+
+template<typename T>
+inline 
+typename CircularBuffer<T>::const_reference CircularBuffer<T>::operator[](size_t index) const {
+	//std::lock_guard<std::mutex> _lck(_mtx);
+	if((index<0)||(index>=_size))
+		abort(); //throw std::out_of_range("Index is out of Range of buffer size");
+	index += _tail;
+	index %= _max_size;
+	return _buff[index];
+}
+
+template<typename T>
+inline 
+typename CircularBuffer<T>::reference CircularBuffer<T>::at(size_t index) {
+	//std::lock_guard<std::mutex> _lck(_mtx);
+	if((index<0)||(index>=_size))
+		abort(); //throw std::out_of_range("Index is out of Range of buffer size");
+	index += _tail;
+	index %= _max_size;
+	return _buff[index];
+}
+
+template<typename T>
+inline 
+typename CircularBuffer<T>::const_reference CircularBuffer<T>::at(size_t index) const {
+	//std::lock_guard<std::mutex> _lck(_mtx);
+	if((index<0)||(index>=_size))
+		abort(); //throw std::out_of_range("Index is out of Range of buffer size");
+	index += _tail;
+	index %= _max_size;
+	return _buff[index];
+}
+
+template<typename T>
+inline 
+typename CircularBuffer<T>::iterator CircularBuffer<T>::begin() {
+	//std::lock_guard<std::mutex> _lck(_mtx);
+	iterator iter;
+	iter._ptrToBuffer = this;
+	iter._offset = _tail;
+	iter._index = 0;
+	iter._reverse = false;
+	return iter;
+}
+
+template<typename T>
+inline 
+typename CircularBuffer<T>::const_iterator CircularBuffer<T>::begin() const{
+	//std::lock_guard<std::mutex> _lck(_mtx);
+	const_iterator iter;
+	iter._ptrToBuffer = this;
+	iter._offset = _tail;
+	iter._index = 0;
+	iter._reverse = false;
+	return iter;
+}
+
+template<typename T>
+inline 
+typename CircularBuffer<T>::iterator CircularBuffer<T>::end() {
+	//std::lock_guard<std::mutex> _lck(_mtx);
+	iterator iter;
+	iter._ptrToBuffer = this;
+	iter._offset = _tail;
+	iter._index = _size;
+	iter._reverse = false;
+	return iter;
+}
+
+template<typename T>
+inline 
+typename CircularBuffer<T>::const_iterator CircularBuffer<T>::end() const{
+	//std::lock_guard<std::mutex> _lck(_mtx);
+	const_iterator iter;
+	iter._ptrToBuffer = this;
+	iter._offset = _tail;
+	iter._index = _size;
+	iter._reverse = false;
+	return iter;
+}
+
+template<typename T>
+inline 
+typename CircularBuffer<T>::const_iterator CircularBuffer<T>::cbegin() const noexcept{
+	//std::lock_guard<std::mutex> _lck(_mtx);
+	const_iterator iter;
+	iter._ptrToBuffer = this;
+	iter._offset = _tail;
+	iter._index = 0;
+	iter._reverse = false;
+	return iter;
+}
+
+template<typename T>
+inline 
+typename CircularBuffer<T>::const_iterator CircularBuffer<T>::cend() const noexcept{
+	//std::lock_guard<std::mutex> _lck(_mtx);
+	const_iterator iter;
+	iter._ptrToBuffer = this;
+	iter._offset = _tail;
+	iter._index = _size;
+	iter._reverse = false;
+	return iter;
+}
+
+template<typename T>
+inline 
+typename CircularBuffer<T>::iterator CircularBuffer<T>::rbegin() noexcept{
+	//std::lock_guard<std::mutex> _lck(_mtx);
+	iterator iter;
+	iter._ptrToBuffer = this;
+	iter._offset = _tail;
+	iter._index = 0;
+	iter._reverse = true;
+	return iter;
+}
+
+template<typename T>
+inline 
+typename CircularBuffer<T>::const_iterator CircularBuffer<T>::rbegin() const noexcept{
+	//std::lock_guard<std::mutex> _lck(_mtx);
+	const_iterator iter;
+	iter._ptrToBuffer = this;
+	iter._offset = _tail;
+	iter._index = 0;
+	iter._reverse = true;
+	return iter;
+}
+
+template<typename T>
+inline 
+typename CircularBuffer<T>::iterator CircularBuffer<T>::rend()  noexcept{
+	//std::lock_guard<std::mutex> _lck(_mtx);
+	iterator iter;
+	iter._ptrToBuffer = this;
+	iter._offset = _tail;
+	iter._index = _size;
+	iter._reverse = true;
+	return iter;
+}
+
+template<typename T>
+inline 
+typename CircularBuffer<T>::const_iterator CircularBuffer<T>::rend() const noexcept{
+	//std::lock_guard<std::mutex> _lck(_mtx);
+	const_iterator iter;
+	iter._ptrToBuffer = this;
+	iter._offset = _tail;
+	iter._index = _size;
+	iter._reverse = true;
+	return iter;
+}
+
+#endif /* CIRCULAR_BUFFER_H */
diff --git a/kernel.cpp b/kernel.cpp
index 26d5b7d..408a19e 100644
--- a/kernel.cpp
+++ b/kernel.cpp
@@ -40,35 +40,28 @@ void kernel_main(void)
     tasking_initialize();
     term.write("Tasking enabled.\n");
 
-    //tasking_spawn([] {
-    //    for (;;) {
-    //        do pit_delay_ms(1);
-    //        while (termBusy);
-
-    //        termBusy = true;
-    //        term.write('B');
-    //        termBusy = false;
-    //    }
-    //}, 256);
-
-    //tasking_spawn([] {
-    //    for (;;) {
-    //        do pit_delay_ms(1);
-    //        while (termBusy);
-
-    //        termBusy = true;
-    //        term.write('C');
-    //        termBusy = false;
-    //    }
-    //}, 256);
-
     for (;;) {
-        pit_delay_ms(100);
-        //while (termBusy);
+        const auto ch = keyboard_read();
+        if (ch)
+            term.write(*ch);
 
-        //termBusy = true;
-        //term.write('A');
-        //termBusy = false;
+        pit_delay_ms(10);
     }
 }
 
+extern "C"
+void abort()
+{
+    term.write("!!! abort() called !!!");
+    asm volatile("cli");
+    for (;;);
+}
+
+extern "C"
+int __cxa_atexit(void (*func)(void *), void *arg, void *dso_handle)
+{
+    return 0;
+}
+
+int __dso_handle = 0;
+
diff --git a/keyboard.cpp b/keyboard.cpp
index 18d7acd..29178f9 100644
--- a/keyboard.cpp
+++ b/keyboard.cpp
@@ -1,33 +1,16 @@
+#include "circularbuffer.hpp"
 #include "idt.hpp"
+#include "keyboard.hpp"
 #include "portio.hpp"
 #include "vgaterminal.hpp"
 
 #include <array>
 #include <cstdint>
 
-#define K_CONTROL_L -1
-#define K_SHIFT_L   -2
-#define K_ALT_L     -3
-#define K_CAPS      -4
-#define K_NUM       -5
-#define K_SCROLL    -6
-#define K_SHIFT_R   -7
-#define K_ESCAPE    -8
-#define K_F1        -10
-#define K_F2        -11
-#define K_F3        -12
-#define K_F4        -13
-#define K_F5        -14
-#define K_F6        -15
-#define K_F7        -16
-#define K_F8        -17
-#define K_F9        -18
-#define K_F10       -19
-#define K_F11       -20
-#define K_F12       -21
-
 extern TextOutput& term;
 
+static CircularBuffer<char> keyboardBuffer;
+
 static const std::array<char, 0x59> ScanCodeSet1 {{
     0, K_ESCAPE,
     '1', '2', '3', '4', '5', '6', '7', '8', '9', '0',
@@ -52,14 +35,29 @@ static constexpr auto keycode(auto ch) {
 
 void keyboard_initialize()
 {
+    keyboardBuffer = CircularBuffer<char>(128);
+
     idt_register_callback(33, [](auto& regs) {
         const auto kc = inb(0x60);
 
         if (!isReleased(kc)) {
             const auto ch = ScanCodeSet1[keycode(kc)];
-            if (ch > 0)
-                term.write(ch);
+            //if (ch > 0)
+            //    term.write(ch);
+
+            keyboardBuffer.push_back(ch);
         }
     });
 }
 
+std::optional<char> keyboard_read()
+{
+    if (keyboardBuffer.empty()) {
+        return {};
+    } else {
+        const auto ch = keyboardBuffer.front();
+        keyboardBuffer.pop_front();
+        return ch;
+    }
+}
+
diff --git a/keyboard.hpp b/keyboard.hpp
index 40b57c9..694ff89 100644
--- a/keyboard.hpp
+++ b/keyboard.hpp
@@ -1,7 +1,32 @@
 #ifndef KEYBOARD_HPP
 #define KEYBOARD_HPP
 
+#include <optional>
+
+#define K_CONTROL_L -1
+#define K_SHIFT_L   -2
+#define K_ALT_L     -3
+#define K_CAPS      -4
+#define K_NUM       -5
+#define K_SCROLL    -6
+#define K_SHIFT_R   -7
+#define K_ESCAPE    -8
+#define K_F1        -10
+#define K_F2        -11
+#define K_F3        -12
+#define K_F4        -13
+#define K_F5        -14
+#define K_F6        -15
+#define K_F7        -16
+#define K_F8        -17
+#define K_F9        -18
+#define K_F10       -19
+#define K_F11       -20
+#define K_F12       -21
+
 void keyboard_initialize();
 
+std::optional<char> keyboard_read();
+
 #endif // KEYBOARD_HPP
 
diff --git a/memory.cpp b/memory.cpp
index 2cc15be..59e2bbe 100644
--- a/memory.cpp
+++ b/memory.cpp
@@ -85,3 +85,12 @@ void *operator new[](std::size_t size)
     return memory_alloc(size);
 }
 
+void operator delete(void *ptr)
+{
+
+}
+
+void operator delete[](void *ptr)
+{
+
+}
diff --git a/memory.hpp b/memory.hpp
index 8955262..0467bf6 100644
--- a/memory.hpp
+++ b/memory.hpp
@@ -1,6 +1,37 @@
 #ifndef MEMORY_HPP
 #define MEMORY_HPP
 
+#include <cstddef>
+#include <type_traits>
+
+template<typename T>
+struct kallocator
+{
+    using value_type = T;
+    using size_type = std::size_t;
+    using difference_type = std::ptrdiff_t;
+    using propagate_on_container_move_assignment = std::true_type;
+    using is_always_equal = std::true_type;
+
+    template<class U>
+    struct rebind {
+        typedef kallocator<U> other;
+    };
+
+    kallocator() = default;
+
+    template<typename U>
+    kallocator(const kallocator<U>&) noexcept {}
+
+    T* allocate(std::size_t n) {
+        return new T[n];
+    }
+
+    void deallocate([[maybe_unused]] T* p, [[maybe_unused]] std::size_t n) {
+
+    }
+};
+
 void memory_initialize();
 
 #endif // MEMORY_HPP