Kernel: TTY now handles keeping terminal buffer

VESA Driver cannot scroll anymore, this is handled by tty

kernel/arch/i386/TTY.cpp

@@ -36,12 +36,8 @@ TTY::TTY()
 
 void TTY::Clear()
 {
-	for (uint32_t i = 0; i < m_width * m_height; i++)
+	for (size_t i = 0; i < m_width * m_height; i++)
-	{
+		m_buffer[i] = { .foreground = m_foreground, .background = m_background, .character = ' ' };
-		m_buffer[i].foreground = m_foreground;
-		m_buffer[i].background = m_background;
-		m_buffer[i].character = ' ';
-	}
 	VESA::Clear(m_background);
 }
 
@@ -248,6 +244,15 @@ void TTY::HandleAnsiEscape(uint16_t ch)
 	}
 }
 
+void TTY::PutCharAt(uint16_t ch, size_t x, size_t y)
+{
+	auto& cell = m_buffer[y * m_width + x];
+	cell.character = ch;
+	cell.foreground = m_foreground;
+	cell.background = m_background;
+	VESA::PutEntryAt(ch, x, y, m_foreground, m_background);
+}
+
 void TTY::PutChar(char ch)
 {
 	uint16_t cp = handle_unicode(ch);
@@ -285,7 +290,7 @@ void TTY::PutChar(char ch)
 			m_ansi_state.mode = '\1';
 			break;
 		default:
-			VESA::PutEntryAt(cp, m_column, m_row, m_foreground, m_background);
+			PutCharAt(cp, m_column, m_row);
 			m_column++;
 			break;
 	}
@@ -298,9 +303,18 @@ void TTY::PutChar(char ch)
 
 	while (m_row >= m_height)
 	{
-		VESA::Scroll();
+		// Shift buffer one line up
+		for (size_t y = 1; y < m_height; y++)
 			for (size_t x = 0; x < m_width; x++)
-			VESA::PutEntryAt(' ', x, m_height - 1, m_foreground, m_background);
+				m_buffer[(y - 1) * m_width + x] = m_buffer[y * m_width + x];
+		// Clear last line in buffer
+		for (size_t x = 0; x < m_width; x++)
+			m_buffer[(m_height - 1) * m_width + x] = { .foreground = m_foreground, .background = m_background, .character = ' ' };
+
+		// Render the whole buffer to the screen
+		for (size_t y = 0; y < m_height; y++)
+			for (size_t x = 0; x < m_width; x++)
+				RenderFromBuffer(x, y);
 
 		m_column = 0;
 		m_row--;
@@ -332,6 +346,31 @@ void TTY::PutCharCurrent(char ch)
 	}
 	else
 	{
+		static size_t x = 0;
+		static size_t y = 0;
 
+		switch (ch)
+		{
+		case '\n':
+			x = 0;
+			y++;
+			break;
+		default:
+			VESA::PutEntryAt(ch, x, y, VESA::Color::BRIGHT_WHITE, VESA::Color::BLACK);
+			break;
+		}
+
+		if (++x == VESA::GetTerminalWidth())
+		{
+			x = 0;
+			y++;
+		}
+
+		if (y == VESA::GetTerminalHeight())
+		{
+			x = 0;
+			y = 0;
+			VESA::Clear(VESA::Color::BLACK);
+		}
 	}
 }

kernel/arch/i386/VESA.cpp

@@ -18,7 +18,7 @@ extern const struct bitmap_font font;
 
 namespace VESA
 {
-	static void*	s_buffer	= nullptr;
+
 	static void*	s_addr		= nullptr;
 	static uint8_t	s_bpp		= 0;
 	static uint32_t s_pitch		= 0;
@@ -28,11 +28,9 @@ namespace VESA
 
 	static void GraphicsPutCharAt(uint16_t ch, uint32_t x, uint32_t y, Color fg, Color bg);
 	static void GraphicsClear(Color color);
-	static void GraphicsScroll();
 
 	static void TextPutCharAt(uint16_t ch, uint32_t x, uint32_t y, Color fg, Color bg);
 	static void TextClear(Color color);
-	static void TextScroll();
 
 	void PutEntryAt(uint16_t ch, uint32_t x, uint32_t y, Color fg, Color bg)
 	{
@@ -54,14 +52,6 @@ namespace VESA
 			return TextClear(color);
 	}
 
-	void Scroll()
-	{
-		if (s_mode == MULTIBOOT_FRAMEBUFFER_TYPE_GRAPHICS)
-			return GraphicsScroll();
-		if (s_mode == MULTIBOOT_FRAMEBUFFER_TYPE_TEXT)
-			return TextScroll();
-	}
-
 	uint32_t GetTerminalWidth()
 	{
 		if (s_mode == MULTIBOOT_FRAMEBUFFER_TYPE_GRAPHICS)
@@ -138,24 +128,6 @@ namespace VESA
 	static void GraphicsSetPixel(uint32_t offset, uint32_t color)
 	{
 		uint32_t* address = (uint32_t*)((uint32_t)s_addr + offset);
-		
-		if (s_buffer)
-		{
-			uint32_t* buffer = (uint32_t*)((uint32_t)s_buffer + offset);
-			switch (s_bpp)
-			{
-				case 24:
-					*buffer = (*buffer & 0xFF000000) | (color & 0x00FFFFFF);
-					*address = *buffer;
-					break;
-				case 32:
-					*buffer = color;
-					*address = color;
-					break;
-			}
-		}
-		else
-		{
 		switch (s_bpp)
 		{
 			case 24:
@@ -166,7 +138,6 @@ namespace VESA
 				break;
 		}
 	}
-	}
 
 	static void GraphicsPutCharAt(uint16_t ch, uint32_t x, uint32_t y, Color fg, Color bg)
 	{
@@ -214,10 +185,6 @@ namespace VESA
 			for (uint32_t y = 0; y < s_height; y++)
 				for (uint32_t x = 0; x < s_width; x++)
 					((uint32_t*)s_addr)[y * bytes_per_row + x] = u32_color;
-			if (s_buffer)
-				for (uint32_t y = 0; y < s_height; y++)
-					for (uint32_t x = 0; x < s_width; x++)
-						((uint32_t*)s_buffer)[y * bytes_per_row + x] = u32_color;
 			return;
 		}
 
@@ -234,52 +201,6 @@ namespace VESA
 		}
 	}
 
-	static void GraphicsScroll()
-	{
-		if (s_bpp == 32)
-		{
-			uint32_t bytes_per_row = s_pitch / 4;
-			for (uint32_t y = 0; y < s_height - font.Height; y++)
-			{
-				for (uint32_t x = 0; x < s_width; x++)
-				{
-					if (s_buffer)
-					{
-						((uint32_t*)s_buffer)[y * bytes_per_row + x] = ((uint32_t*)s_buffer)[(y + font.Height) * bytes_per_row + x];
-						((uint32_t*)s_addr  )[y * bytes_per_row + x] = ((uint32_t*)s_buffer)[(y + font.Height) * bytes_per_row + x];
-					}
-					else
-					{
-						((uint32_t*)s_addr  )[y * bytes_per_row + x] = ((uint32_t*)s_addr  )[(y + font.Height) * bytes_per_row + x];
-					}
-				}
-			}
-			return;
-		}
-
-		uint32_t row_offset_out = 0;
-		uint32_t row_offset_in  = font.Height * s_pitch;
-
-		for (uint32_t y = 0; y < s_height - 1; y++)
-		{
-			if (s_buffer)
-			{
-				memcpy((void*)((uint32_t)s_buffer + row_offset_out), (void*)((uint32_t)s_buffer + row_offset_in), s_width * s_bpp);
-				memcpy((void*)((uint32_t)s_addr   + row_offset_out), (void*)((uint32_t)s_buffer + row_offset_in), s_width * s_bpp);
-			}
-			else
-			{
-				memcpy((void*)((uint32_t)s_addr   + row_offset_out), (void*)((uint32_t)s_addr + row_offset_in), s_width * s_bpp);
-			}
-			row_offset_out += s_pitch;
-			row_offset_in  += s_pitch;
-		}
-	}
-
-
-
-
-
 	static inline uint8_t TextColor(Color fg, Color bg)
 	{
 		return (((uint8_t)bg & 0x0F) << 4) | ((uint8_t)fg & 0x0F);
@@ -303,17 +224,4 @@ namespace VESA
 				TextPutCharAt(' ', x, y, Color::BRIGHT_WHITE, color);
 	}
 
-	static void TextScroll()
-	{
-		for (uint32_t y = 1; y < s_height; y++)
-		{
-			for (uint32_t x = 0; x < s_width; x++)
-			{
-				uint32_t index1 = (y - 0) * s_width + x;
-				uint32_t index2 = (y - 1) * s_width + x;
-				((uint16_t*)s_addr)[index2] = ((uint16_t*)s_addr)[index1];
-			}
-		}
-	}
-
 }

kernel/include/kernel/TTY.h

@@ -19,13 +19,19 @@ private:
 	void ResetAnsiEscape();
 	void HandleAnsiSGR();
 	void HandleAnsiEscape(uint16_t ch);
+	void PutCharAt(uint16_t ch, size_t x, size_t y);
+	inline void RenderFromBuffer(size_t x, size_t y)
+	{
+		const auto& cell = m_buffer[y * m_width + x];
+		VESA::PutEntryAt(cell.character, x, y, cell.foreground, cell.background);
+	}
 
 private:
 	struct Cell
 	{
 		VESA::Color foreground = VESA::Color::BRIGHT_WHITE;
 		VESA::Color background = VESA::Color::BLACK;
-		uint8_t		character = ' ';
+		uint16_t	character = ' ';
 	};
 
 	struct AnsiState

kernel/include/kernel/VESA.h

@@ -28,7 +28,6 @@ namespace VESA
 	bool Initialize();
 	void PutEntryAt(uint16_t, uint32_t, uint32_t, Color, Color);
 	void Clear(Color);
-	void Scroll();
 
 	uint32_t GetTerminalWidth();
 	uint32_t GetTerminalHeight();