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	 21d5f4ada1
			
		
	
	
		21d5f4ada1
		
	
	
	
	
		
			
			This was supposed to be the foundation for some kind of pre-kernel environment, but nobody is working on it right now, so let's move everything back into the kernel and remove all the confusion.
		
			
				
	
	
		
			602 lines
		
	
	
	
		
			15 KiB
		
	
	
	
		
			C++
		
	
	
	
	
	
			
		
		
	
	
			602 lines
		
	
	
	
		
			15 KiB
		
	
	
	
		
			C++
		
	
	
	
	
	
| /*
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|  * Copyright (c) 2018-2020, Andreas Kling <kling@serenityos.org>
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|  * All rights reserved.
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|  *
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|  * Redistribution and use in source and binary forms, with or without
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|  * modification, are permitted provided that the following conditions are met:
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|  *
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|  * 1. Redistributions of source code must retain the above copyright notice, this
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|  *    list of conditions and the following disclaimer.
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|  *
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|  * 2. Redistributions in binary form must reproduce the above copyright notice,
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|  *    this list of conditions and the following disclaimer in the documentation
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|  *    and/or other materials provided with the distribution.
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|  *
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|  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
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|  * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
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|  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
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|  * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
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|  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
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|  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
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|  * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
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|  * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
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|  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
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|  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
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|  */
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| 
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| #include "VirtualConsole.h"
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| #include <AK/String.h>
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| #include <Kernel/Arch/i386/CPU.h>
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| #include <Kernel/Devices/KeyboardDevice.h>
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| #include <Kernel/Heap/kmalloc.h>
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| #include <Kernel/IO.h>
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| #include <Kernel/StdLib.h>
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| 
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| namespace Kernel {
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| 
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| static u8* s_vga_buffer;
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| static VirtualConsole* s_consoles[6];
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| static int s_active_console;
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| 
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| void VirtualConsole::get_vga_cursor(u8& row, u8& column)
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| {
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|     u16 value;
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|     IO::out8(0x3d4, 0x0e);
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|     value = IO::in8(0x3d5) << 8;
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|     IO::out8(0x3d4, 0x0f);
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|     value |= IO::in8(0x3d5);
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|     row = value / columns();
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|     column = value % columns();
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| }
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| 
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| void VirtualConsole::flush_vga_cursor()
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| {
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|     u16 value = m_current_vga_start_address + (m_cursor_row * columns() + m_cursor_column);
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|     IO::out8(0x3d4, 0x0e);
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|     IO::out8(0x3d5, MSB(value));
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|     IO::out8(0x3d4, 0x0f);
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|     IO::out8(0x3d5, LSB(value));
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| }
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| 
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| void VirtualConsole::initialize()
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| {
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|     s_vga_buffer = (u8*)0xc00b8000;
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|     memset(s_consoles, 0, sizeof(s_consoles));
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|     s_active_console = -1;
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| }
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| 
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| void VirtualConsole::set_graphical(bool graphical)
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| {
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|     if (graphical)
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|         set_vga_start_row(0);
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| 
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|     m_graphical = graphical;
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| }
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| 
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| VirtualConsole::VirtualConsole(unsigned index, InitialContents initial_contents)
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|     : TTY(4, index)
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|     , m_index(index)
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| {
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|     sprintf(m_tty_name, "/dev/tty%u", m_index);
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|     set_size(80, 25);
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|     m_horizontal_tabs = static_cast<u8*>(kmalloc_eternal(columns()));
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|     for (unsigned i = 0; i < columns(); ++i)
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|         m_horizontal_tabs[i] = (i % 8) == 0;
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|     // Rightmost column is always last tab on line.
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|     m_horizontal_tabs[columns() - 1] = 1;
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| 
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|     s_consoles[index] = this;
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|     m_buffer = (u8*)kmalloc_eternal(rows() * columns() * 2);
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|     if (initial_contents == AdoptCurrentVGABuffer) {
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|         memcpy(m_buffer, s_vga_buffer, rows() * columns() * 2);
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|         get_vga_cursor(m_cursor_row, m_cursor_column);
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|     } else {
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|         u16* line_mem = reinterpret_cast<u16*>(m_buffer);
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|         for (u16 i = 0; i < rows() * columns(); ++i)
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|             line_mem[i] = 0x0720;
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|     }
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| }
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| 
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| VirtualConsole::~VirtualConsole()
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| {
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|     ASSERT_NOT_REACHED();
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| }
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| 
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| void VirtualConsole::clear()
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| {
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|     u16* linemem = m_active ? (u16*)s_vga_buffer : (u16*)m_buffer;
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|     for (u16 i = 0; i < rows() * columns(); ++i)
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|         linemem[i] = 0x0720;
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|     if (m_active)
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|         set_vga_start_row(0);
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|     set_cursor(0, 0);
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| }
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| 
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| void VirtualConsole::switch_to(unsigned index)
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| {
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|     if ((int)index == s_active_console)
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|         return;
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|     ASSERT(index < 6);
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|     ASSERT(s_consoles[index]);
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| 
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|     InterruptDisabler disabler;
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|     if (s_active_console != -1) {
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|         auto* active_console = s_consoles[s_active_console];
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|         // We won't know how to switch away from a graphical console until we
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|         // can set the video mode on our own. Just stop anyone from trying for
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|         // now.
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|         if (active_console->is_graphical())
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|             return;
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|         active_console->set_active(false);
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|     }
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|     dbg() << "VC: Switch to " << index << " (" << s_consoles[index] << ")";
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|     s_active_console = index;
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|     s_consoles[s_active_console]->set_active(true);
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|     Console::the().set_implementation(s_consoles[s_active_console]);
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| }
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| 
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| void VirtualConsole::set_active(bool b)
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| {
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|     if (b == m_active)
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|         return;
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| 
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|     InterruptDisabler disabler;
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| 
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|     m_active = b;
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|     if (!m_active) {
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|         memcpy(m_buffer, m_current_vga_window, rows() * columns() * 2);
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|         KeyboardDevice::the().set_client(nullptr);
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|         return;
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|     }
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| 
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|     memcpy(s_vga_buffer, m_buffer, rows() * columns() * 2);
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|     set_vga_start_row(0);
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|     flush_vga_cursor();
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| 
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|     KeyboardDevice::the().set_client(this);
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| }
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| 
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| inline bool is_valid_parameter_character(u8 ch)
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| {
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|     return ch >= 0x30 && ch <= 0x3f;
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| }
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| 
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| inline bool is_valid_intermediate_character(u8 ch)
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| {
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|     return ch >= 0x20 && ch <= 0x2f;
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| }
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| 
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| inline bool is_valid_final_character(u8 ch)
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| {
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|     return ch >= 0x40 && ch <= 0x7e;
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| }
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| 
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| enum class VGAColor : u8 {
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|     Black = 0,
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|     Blue,
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|     Green,
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|     Cyan,
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|     Red,
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|     Magenta,
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|     Brown,
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|     LightGray,
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|     DarkGray,
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|     BrightBlue,
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|     BrightGreen,
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|     BrightCyan,
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|     BrightRed,
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|     BrightMagenta,
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|     Yellow,
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|     White,
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| };
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| 
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| enum class ANSIColor : u8 {
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|     Black = 0,
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|     Red,
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|     Green,
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|     Brown,
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|     Blue,
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|     Magenta,
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|     Cyan,
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|     LightGray,
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|     DarkGray,
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|     BrightRed,
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|     BrightGreen,
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|     Yellow,
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|     BrightBlue,
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|     BrightMagenta,
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|     BrightCyan,
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|     White,
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| };
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| 
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| static inline VGAColor ansi_color_to_vga(ANSIColor color)
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| {
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|     switch (color) {
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|     case ANSIColor::Black:
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|         return VGAColor::Black;
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|     case ANSIColor::Red:
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|         return VGAColor::Red;
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|     case ANSIColor::Brown:
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|         return VGAColor::Brown;
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|     case ANSIColor::Blue:
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|         return VGAColor::Blue;
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|     case ANSIColor::Magenta:
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|         return VGAColor::Magenta;
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|     case ANSIColor::Green:
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|         return VGAColor::Green;
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|     case ANSIColor::Cyan:
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|         return VGAColor::Cyan;
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|     case ANSIColor::LightGray:
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|         return VGAColor::LightGray;
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|     case ANSIColor::DarkGray:
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|         return VGAColor::DarkGray;
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|     case ANSIColor::BrightRed:
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|         return VGAColor::BrightRed;
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|     case ANSIColor::BrightGreen:
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|         return VGAColor::BrightGreen;
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|     case ANSIColor::Yellow:
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|         return VGAColor::Yellow;
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|     case ANSIColor::BrightBlue:
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|         return VGAColor::BrightBlue;
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|     case ANSIColor::BrightMagenta:
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|         return VGAColor::BrightMagenta;
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|     case ANSIColor::BrightCyan:
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|         return VGAColor::BrightCyan;
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|     case ANSIColor::White:
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|         return VGAColor::White;
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|     }
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|     ASSERT_NOT_REACHED();
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|     return VGAColor::LightGray;
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| }
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| 
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| static inline u8 ansi_color_to_vga(u8 color)
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| {
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|     return (u8)ansi_color_to_vga((ANSIColor)color);
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| }
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| 
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| void VirtualConsole::escape$m(const Vector<unsigned>& params)
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| {
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|     for (auto param : params) {
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|         switch (param) {
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|         case 0:
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|             // Reset
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|             m_current_attribute = 0x07;
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|             break;
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|         case 1:
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|             // Bold
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|             m_current_attribute |= 8;
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|             break;
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|         case 30:
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|         case 31:
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|         case 32:
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|         case 33:
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|         case 34:
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|         case 35:
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|         case 36:
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|         case 37:
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|             // Foreground color
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|             m_current_attribute &= ~0x7;
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|             m_current_attribute |= ansi_color_to_vga(param - 30);
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|             break;
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|         case 40:
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|         case 41:
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|         case 42:
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|         case 43:
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|         case 44:
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|         case 45:
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|         case 46:
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|         case 47:
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|             // Background color
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|             m_current_attribute &= ~0x70;
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|             m_current_attribute |= ansi_color_to_vga(param - 30) << 8;
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|             break;
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|         }
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|     }
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| }
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| 
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| void VirtualConsole::escape$s(const Vector<unsigned>&)
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| {
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|     m_saved_cursor_row = m_cursor_row;
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|     m_saved_cursor_column = m_cursor_column;
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| }
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| 
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| void VirtualConsole::escape$u(const Vector<unsigned>&)
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| {
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|     set_cursor(m_saved_cursor_row, m_saved_cursor_column);
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| }
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| 
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| void VirtualConsole::escape$H(const Vector<unsigned>& params)
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| {
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|     unsigned row = 1;
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|     unsigned col = 1;
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|     if (params.size() >= 1)
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|         row = params[0];
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|     if (params.size() >= 2)
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|         col = params[1];
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|     set_cursor(row - 1, col - 1);
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| }
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| 
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| void VirtualConsole::escape$A(const Vector<unsigned>& params)
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| {
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|     int num = 1;
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|     if (params.size() >= 1)
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|         num = params[0];
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|     int new_row = (int)m_cursor_row - num;
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|     if (new_row < 0)
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|         new_row = 0;
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|     set_cursor(new_row, m_cursor_column);
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| }
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| 
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| void VirtualConsole::escape$D(const Vector<unsigned>& params)
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| {
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|     int num = 1;
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|     if (params.size() >= 1)
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|         num = params[0];
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|     int new_column = (int)m_cursor_column - num;
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|     if (new_column < 0)
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|         new_column = 0;
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|     set_cursor(m_cursor_row, new_column);
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| }
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| 
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| void VirtualConsole::escape$J(const Vector<unsigned>& params)
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| {
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|     int mode = 0;
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|     if (params.size() >= 1)
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|         mode = params[0];
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|     switch (mode) {
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|     case 0:
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|         // FIXME: Clear from cursor to end of screen.
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|         ASSERT_NOT_REACHED();
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|         break;
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|     case 1:
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|         // FIXME: Clear from cursor to beginning of screen.
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|         ASSERT_NOT_REACHED();
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|         break;
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|     case 2:
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|         clear();
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|         break;
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|     case 3:
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|         // FIXME: <esc>[3J should also clear the scrollback buffer.
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|         clear();
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|         break;
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|     }
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| }
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| 
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| void VirtualConsole::execute_escape_sequence(u8 final)
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| {
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|     auto paramparts = String::copy(m_parameters).split(';');
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|     Vector<unsigned> params;
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|     for (auto& parampart : paramparts) {
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|         bool ok;
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|         unsigned value = parampart.to_uint(ok);
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|         if (!ok) {
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|             // FIXME: Should we do something else?
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|             return;
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|         }
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|         params.append(value);
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|     }
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|     switch (final) {
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|     case 'A':
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|         escape$A(params);
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|         break;
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|     case 'D':
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|         escape$D(params);
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|         break;
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|     case 'H':
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|         escape$H(params);
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|         break;
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|     case 'J':
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|         escape$J(params);
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|         break;
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|     case 'm':
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|         escape$m(params);
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|         break;
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|     case 's':
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|         escape$s(params);
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|         break;
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|     case 'u':
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|         escape$u(params);
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|         break;
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|     default:
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|         break;
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|     }
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| 
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|     m_parameters.clear();
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|     m_intermediates.clear();
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| }
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| 
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| void VirtualConsole::clear_vga_row(u16 row)
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| {
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|     u16* linemem = (u16*)&m_current_vga_window[row * 160];
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|     for (u16 i = 0; i < columns(); ++i)
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|         linemem[i] = 0x0720;
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| }
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| 
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| void VirtualConsole::scroll_up()
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| {
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|     if (m_cursor_row == (rows() - 1)) {
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|         if (m_active) {
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|             if (m_vga_start_row >= 160) {
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|                 memcpy(s_vga_buffer, m_current_vga_window + 160, (rows() - 1) * columns() * 2);
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|                 set_vga_start_row(0);
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|                 clear_vga_row(24);
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|             } else {
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|                 set_vga_start_row(m_vga_start_row + 1);
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|                 clear_vga_row(24);
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|             }
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|         } else {
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|             memmove(m_buffer, m_buffer + 160, 160 * 24);
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|             u16* linemem = (u16*)&m_buffer[24 * 160];
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|             for (u16 i = 0; i < columns(); ++i)
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|                 linemem[i] = 0x0720;
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|         }
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|     } else {
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|         ++m_cursor_row;
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|     }
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|     m_cursor_column = 0;
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| }
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| 
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| void VirtualConsole::set_cursor(unsigned row, unsigned column)
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| {
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|     ASSERT(row < rows());
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|     ASSERT(column < columns());
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|     m_cursor_row = row;
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|     m_cursor_column = column;
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|     if (m_active)
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|         flush_vga_cursor();
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| }
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| 
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| void VirtualConsole::put_character_at(unsigned row, unsigned column, u8 ch)
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| {
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|     ASSERT(row < rows());
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|     ASSERT(column < columns());
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|     u16 cur = (row * 160) + (column * 2);
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|     if (m_active) {
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|         u16 cur = (row * 160) + (column * 2);
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|         m_current_vga_window[cur] = ch;
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|         m_current_vga_window[cur + 1] = m_current_attribute;
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|     } else {
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|         m_buffer[cur] = ch;
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|         m_buffer[cur + 1] = m_current_attribute;
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|     }
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| }
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| 
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| void VirtualConsole::on_char(u8 ch)
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| {
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|     // ignore writes in graphical mode
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|     if (m_graphical)
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|         return;
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| 
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|     switch (m_escape_state) {
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|     case ExpectBracket:
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|         if (ch == '[')
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|             m_escape_state = ExpectParameter;
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|         else
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|             m_escape_state = Normal;
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|         return;
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|     case ExpectParameter:
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|         if (is_valid_parameter_character(ch)) {
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|             m_parameters.append(ch);
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|             return;
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|         }
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|         m_escape_state = ExpectIntermediate;
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|         [[fallthrough]];
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|     case ExpectIntermediate:
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|         if (is_valid_intermediate_character(ch)) {
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|             m_intermediates.append(ch);
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|             return;
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|         }
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|         m_escape_state = ExpectFinal;
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|         [[fallthrough]];
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|     case ExpectFinal:
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|         if (is_valid_final_character(ch)) {
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|             m_escape_state = Normal;
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|             execute_escape_sequence(ch);
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|             return;
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|         }
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|         m_escape_state = Normal;
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|         return;
 | |
|     case Normal:
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|         break;
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|     }
 | |
| 
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|     switch (ch) {
 | |
|     case '\0':
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|         return;
 | |
|     case '\033':
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|         m_escape_state = ExpectBracket;
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|         return;
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|     case 8: // Backspace
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|         if (m_cursor_column) {
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|             set_cursor(m_cursor_row, m_cursor_column - 1);
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|             put_character_at(m_cursor_row, m_cursor_column, ' ');
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|             return;
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|         }
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|         break;
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|     case '\a':
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|         // FIXME: Bell!
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|         return;
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|     case '\t': {
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|         for (unsigned i = m_cursor_column; i < columns(); ++i) {
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|             if (m_horizontal_tabs[i]) {
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|                 set_cursor(m_cursor_row, i);
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|                 return;
 | |
|             }
 | |
|         }
 | |
|         return;
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|     }
 | |
|     case '\n':
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|         scroll_up();
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|         set_cursor(m_cursor_row, m_cursor_column);
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|         return;
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|     }
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| 
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|     put_character_at(m_cursor_row, m_cursor_column, ch);
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| 
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|     ++m_cursor_column;
 | |
|     if (m_cursor_column >= columns())
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|         scroll_up();
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|     set_cursor(m_cursor_row, m_cursor_column);
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| }
 | |
| 
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| void VirtualConsole::on_key_pressed(KeyboardDevice::Event key)
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| {
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|     // ignore keyboard in graphical mode
 | |
|     if (m_graphical)
 | |
|         return;
 | |
| 
 | |
|     if (!key.is_press())
 | |
|         return;
 | |
|     if (key.ctrl()) {
 | |
|         if (key.character >= 'a' && key.character <= 'z') {
 | |
|             emit(key.character - 'a' + 1);
 | |
|             return;
 | |
|         } else if (key.character == '\\') {
 | |
|             emit(0x1c);
 | |
|             return;
 | |
|         }
 | |
|     }
 | |
|     emit(key.character);
 | |
| }
 | |
| 
 | |
| void VirtualConsole::on_sysconsole_receive(u8 ch)
 | |
| {
 | |
|     InterruptDisabler disabler;
 | |
|     auto old_attribute = m_current_attribute;
 | |
|     m_current_attribute = 0x03;
 | |
|     on_char(ch);
 | |
|     m_current_attribute = old_attribute;
 | |
| }
 | |
| 
 | |
| ssize_t VirtualConsole::on_tty_write(const u8* data, ssize_t size)
 | |
| {
 | |
|     InterruptDisabler disabler;
 | |
|     for (ssize_t i = 0; i < size; ++i)
 | |
|         on_char(data[i]);
 | |
|     return size;
 | |
| }
 | |
| 
 | |
| StringView VirtualConsole::tty_name() const
 | |
| {
 | |
|     return m_tty_name;
 | |
| }
 | |
| 
 | |
| void VirtualConsole::echo(u8 ch)
 | |
| {
 | |
|     if (should_echo_input()) {
 | |
|         on_tty_write(&ch, 1);
 | |
|     }
 | |
| }
 | |
| 
 | |
| void VirtualConsole::set_vga_start_row(u16 row)
 | |
| {
 | |
|     m_vga_start_row = row;
 | |
|     m_current_vga_start_address = row * columns();
 | |
|     m_current_vga_window = s_vga_buffer + row * 160;
 | |
|     IO::out8(0x3d4, 0x0c);
 | |
|     IO::out8(0x3d5, MSB(m_current_vga_start_address));
 | |
|     IO::out8(0x3d4, 0x0d);
 | |
|     IO::out8(0x3d5, LSB(m_current_vga_start_address));
 | |
| }
 | |
| 
 | |
| }
 |