Initial commit

20 files changed, 1598 insertions, 0 deletions

diff --git a/stage3/colors.asm b/stage3/colors.asm
new file mode 100644
index 0000000..a53efff
--- /dev/null
+++ b/stage3/colors.asm
@@ -0,0 +1,16 @@
+%define COLOR_BLACK 0
+%define COLOR_BLUE 1
+%define COLOR_GREEN 2
+%define COLOR_CYAN 3
+%define COLOR_RED 4
+%define COLOR_MAGENTA 5
+%define COLOR_BROWN 6
+%define COLOR_LIGHT_GREY 7
+%define COLOR_DARK_GREY 8
+%define COLOR_LIGHT_BLUE 9
+%define COLOR_LIGHT_GREEN 10
+%define COLOR_LIGHT_CYAN 11
+%define COLOR_LIGHT_RED 12
+%define COLOR_LIGHT_MAGENTA 13
+%define COLOR_LIGHT_BROWN 14
+%define COLOR_WHITE 15
diff --git a/stage3/def.h b/stage3/def.h
new file mode 100644
index 0000000..c2f8311
--- /dev/null
+++ b/stage3/def.h
@@ -0,0 +1,21 @@
+#ifndef _DEF_H_
+#define _DEF_H_
+
+#define nil ((void *) 0x0)
+
+typedef unsigned char u8;
+typedef signed char i8;
+
+typedef unsigned short u16;
+typedef short i16;
+
+typedef unsigned int u32;
+typedef int i32;
+
+typedef unsigned long u64;
+typedef long i64;
+
+typedef u64 usize;
+typedef i64 isize;
+
+#endif
diff --git a/stage3/font.asm b/stage3/font.asm
new file mode 100644
index 0000000..b73edab
--- /dev/null
+++ b/stage3/font.asm
@@ -0,0 +1,243 @@
+global debug
+
+%define GFXINFO 0x1000-10
+%define PITCH GFXINFO+0
+%define WIDTH GFXINFO+2
+%define HEIGHT GFXINFO+4
+%define FRAMEBUFFER GFXINFO+6
+
+section .text
+
+; str in rdi
+debug:
+	mov r9, [line]
+
+	mov rax, rcx
+	mov rbx, 15
+	xor rdx, rdx
+	mul rbx
+
+	cmp rax, [HEIGHT]
+	jmp .char
+
+	xor rax, rax
+	xor r9, r9
+
+.char:
+	xor rax, rax
+
+	mov al, [rdi]
+	cmp al, 0
+	je .return
+
+	cmp al, ' '
+	je .space
+
+	cmp al, 'a'
+	jb .invalid
+
+	cmp al, 'z'
+	ja .invalid
+
+	sub al, 'a'
+	mov bl, 15
+	mul bl
+
+	add rax, letters
+	mov r8, rax
+
+	jmp .render
+
+.space:
+	mov r8, letters.space
+
+.render:
+
+.target:
+	xor rdx, rdx
+	mul [PITCH]
+
+	xor rbx, rbx
+	mov ebx, [FRAMEBUFFER]
+	add rax, rbx
+
+	inc rdi
+	jmp debug
+
+.return:
+	ret
+
+.invalid:
+	mov rdi, .invalid_msg
+	call debug
+	jmp $
+
+.invalid_msg: "invalid character in message", 0
+
+section .data
+
+line: dq 0
+
+letters:
+.a: db
+1, 1, 1,
+1, 0, 1,
+1, 1, 1,
+1, 0, 1,
+1, 0, 1
+.b: db
+1, 1, 0,
+1, 0, 1,
+1, 1, 1,
+1, 0, 1,
+1, 1, 1
+.c: db
+1, 1, 1,
+1, 0, 0,
+1, 0, 0,
+1, 0, 0,
+1, 1, 1
+.d: db
+1, 1, 0,
+1, 0, 1,
+1, 0, 1,
+1, 0, 1,
+1, 1, 1
+e: db
+1, 1, 1,
+1, 0, 0,
+1, 1, 1,
+1, 0, 0,
+1, 1, 1
+f: db
+1, 1, 1,
+1, 0, 0,
+1, 1, 1,
+1, 0, 0,
+1, 0, 0
+g: db
+1, 1, 1,
+1, 0, 0,
+1, 0, 1,
+1, 0, 1,
+1, 1, 1
+h: db
+1, 0, 1,
+1, 0, 1,
+1, 1, 1,
+1, 0, 1,
+1, 0, 1
+i: db
+0, 1, 0,
+0, 1, 0,
+0, 1, 0,
+0, 1, 0,
+0, 1, 0
+j: db
+0, 0, 1,
+0, 0, 1,
+0, 0, 1,
+0, 0, 1,
+1, 1, 1
+k: db
+1, 0, 1,
+1, 1, 0,
+1, 0, 0,
+1, 1, 0,
+1, 0, 1,
+l: db
+1, 0, 0,
+1, 0, 0,
+1, 0, 0,
+1, 0, 0,
+1, 1, 1
+m: db
+1, 0, 1,
+1, 1, 1,
+1, 0, 1,
+1, 0, 1,
+1, 0, 1
+n: db
+1, 0, 1,
+1, 0, 1,
+1, 1, 1,
+1, 1, 1,
+1, 0, 1
+o: db
+1, 1, 1,
+1, 0, 1,
+1, 0, 1,
+1, 0, 1,
+1, 1, 1
+p: db
+1, 1, 1,
+1, 0, 1,
+1, 1, 1,
+1, 0, 0,
+1, 0, 0
+q: db
+1, 1, 1,
+1, 0, 1,
+1, 1, 1,
+1, 1, 1,
+0, 0, 1
+r: db
+1, 1, 1,
+1, 0, 1,
+1, 1, 1,
+1, 1, 0,
+1, 0, 1
+s: db
+1, 1, 1,
+1, 0, 0,
+1, 1, 1,
+0, 0, 1,
+1, 1, 1
+t: db
+1, 1, 1,
+0, 1, 0,
+0, 1, 0,
+0, 1, 0,
+0, 1, 0
+u: db
+1, 0, 1,
+1, 0, 1,
+1, 0, 1,
+1, 0, 1,
+1, 1, 1
+v: db
+1, 0, 1,
+1, 0, 1,
+1, 0, 1,
+1, 0, 1,
+0, 1, 0
+w: db
+1, 0, 1,
+1, 0, 1,
+1, 0, 1,
+1, 1, 1,
+1, 0, 1
+x: db
+1, 0, 1,
+1, 0, 1,
+0, 1, 0,
+1, 0, 1,
+1, 0, 1
+y: db
+1, 0, 1,
+1, 0, 1,
+1, 1, 1,
+0, 1, 0,
+0, 1, 0
+z: db
+1, 1, 1,
+0, 0, 1,
+0, 1, 0
+1, 0, 0
+1, 1, 1
+.space:
+0, 0, 0,
+0, 0, 0,
+0, 0, 0,
+0, 0, 0,
+0, 0, 0
diff --git a/stage3/framebuffer.asm b/stage3/framebuffer.asm
new file mode 100644
index 0000000..e55ad04
--- /dev/null
+++ b/stage3/framebuffer.asm
@@ -0,0 +1,176 @@
+%include "stage3/colors.asm"
+global print_chr, print_str, print_dec, print_hex, clear_screen, newline
+extern memcpy
+
+section .data
+
+pos:
+.row: db 0
+.col: db 0
+
+cursor: dq 0xB8000
+color: db COLOR_WHITE | (COLOR_BLACK << 4)
+
+section .text
+
+set_color:
+	shl sil, 4
+	add dil, sil
+	mov [color], dil
+
+update_cursor:
+	mov rbx, [cursor]
+	sub rbx, 0xB8000
+	shr rbx, 1
+
+	mov dx, 0x3D4
+	mov al, 14
+	out dx, al
+
+	mov dx, 0x3D5
+	mov al, bh
+	out dx, al
+
+	mov dx, 0x3D4
+	mov al, 15
+	out dx, al
+
+	mov dx, 0x3D5
+	mov al, bl
+	out dx, al
+
+	ret
+
+set_chr:
+	mov rax, [cursor]
+	mov byte[rax], dil
+	inc rax
+	mov dil, [color]
+	mov [rax], dil
+	inc rax
+	mov [cursor], rax
+	jmp update_cursor
+
+vertical_tab:
+	mov al, [pos.row]
+	inc al
+	cmp al, 25
+	je .scroll
+	mov [pos.row], al
+	mov rax, [cursor]
+	add rax, 160
+	mov [cursor], rax
+	jmp update_cursor
+.scroll:
+	mov rdi, 0xB8000
+	mov rsi, 0xB80A0
+	mov rdx, 0xF00
+	jmp memcpy
+
+carriage_return:
+	mov rax, [cursor]
+	xor rbx, rbx
+	mov bl, [pos.col]
+	shl bl, 1
+	sub rax, rbx
+	mov [cursor], rax
+	mov byte[pos.col], 0
+	jmp update_cursor
+
+newline:
+	call vertical_tab
+	jmp carriage_return
+
+print_chr:
+	cmp dil, 10
+	je newline
+	cmp dil, 11
+	je vertical_tab
+	cmp dil, 13
+	je carriage_return
+	mov al, [pos.col]
+	inc al
+	cmp al, 80
+	je .newline
+	mov [pos.col], al
+	jmp set_chr
+.newline:
+	push rdi
+	call newline
+	pop rdi
+	jmp set_chr
+
+print_str:
+	mov rax, rdi
+.print:
+	mov dil, [rax]
+	cmp dil, 0
+	je .return
+	push rax
+	call print_chr
+	pop rax
+	inc rax
+	jmp .print
+.return:
+	ret
+
+print_hex:
+	mov rsi, 0x10
+	jmp print_num
+print_dec:
+	mov rsi, 10
+print_num:
+	mov rax, rdi
+	xor rcx, rcx
+.convert:
+	inc rcx
+	xor rdx, rdx
+	div rsi
+	cmp dl, 10
+	jb .digit
+	add dl, 'A'-10
+	jmp .next
+.digit:
+	add dl, '0'
+.next:
+	push rdx
+	cmp rax, 0
+	jne .convert
+.print:
+	cmp rcx, 0
+	je .return
+	dec rcx
+	pop rdi
+	push rcx
+	call print_chr
+	pop rcx
+	jmp .print
+.return:
+	ret
+
+clear_screen:
+	push rbx
+	push r12
+	push r13
+	push r14
+	push r15
+
+	mov qword[cursor], 0xB8000
+.clr:
+	cmp qword[cursor], 0xB8FA0
+	je .return
+	mov dil, ' '
+	call set_chr
+	jmp .clr
+.return:
+	mov qword[cursor], 0xB8000
+	mov byte[pos.row], 0
+	mov byte[pos.col], 0
+	call update_cursor
+
+	pop r15
+	pop r14
+	pop r13
+	pop r12
+	pop rbx
+	ret
diff --git a/stage3/fut/linkgen.lua b/stage3/fut/linkgen.lua
new file mode 100755
index 0000000..f7a6d21
--- /dev/null
+++ b/stage3/fut/linkgen.lua
@@ -0,0 +1,101 @@
+#!/usr/bin/env lua
+--[[
+
+--- trigger warning: brain damage ---
+
+BOGUS DYNAMIC LINKING v69.420 by LIZZY FLECKENSTEIN
+
+How this works:
+⠀⠀⠀⠀⠀⢰⡿⠋⠁⠀⠀⠈⠉⠙⠻⣷⣄⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀
+⠀⠀⠀⠀⢀⣿⠇⠀⢀⣴⣶⡾⠿⠿⠿⢿⣿⣦⡀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀
+⠀⠀⣀⣀⣸⡿⠀⠀⢸⣿⣇⠀⠀⠀⠀⠀⠀⠙⣷⡀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀
+⠀⣾⡟⠛⣿⡇⠀⠀⢸⣿⣿⣷⣤⣤⣤⣤⣶⣶⣿⠇⠀⠀⠀⠀⠀⠀⠀⣀⠀⠀
+⢀⣿⠀⢀⣿⡇⠀⠀⠀⠻⢿⣿⣿⣿⣿⣿⠿⣿⡏⠀⠀⠀⠀⢴⣶⣶⣿⣿⣿⣆
+⢸⣿⠀⢸⣿⡇⠀⠀⠀⠀⠀⠈⠉⠁⠀⠀⠀⣿⡇⣀⣠⣴⣾⣮⣝⠿⠿⠿⣻⡟
+⢸⣿⠀⠘⣿⡇⠀⠀⠀⠀⠀⠀⠀⣠⣶⣾⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⡿⠁⠉⠀
+⠸⣿⠀⠀⣿⡇⠀⠀⠀⠀⠀⣠⣾⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⡿⠟⠉⠀⠀⠀⠀
+⠀⠻⣷⣶⣿⣇⠀⠀⠀⢠⣼⣿⣿⣿⣿⣿⣿⣿⣛⣛⣻⠉⠁⠀⠀⠀⠀⠀⠀⠀
+⠀⠀⠀⠀⢸⣿⠀⠀⠀⢸⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⡇⠀⠀⠀⠀⠀⠀⠀⠀
+⠀⠀⠀⠀⢸⣿⣀⣀⣀⣼⡿⢿⣿⣿⣿⣿⣿⡿⣿⣿⡿
+
+Amogus sus 😳 ((impassta))
+
+I FUCKING HATE TEH ANTICRIST!!!!
+WE GOT YOU SURROUNDEND, USE DYNAMIC LINKING
+
+:trollface:
+
+]]
+
+-- in
+local hdr_kern = io.open("sys_kern.h", "r")
+-- out
+local hdr_user = io.open("sys_user.h", "w")
+local src_kern = io.open("sys_kern.c", "w")
+local src_user = io.open("sys_user.c", "w")
+
+local count = 0
+local calltable = "0x500"
+
+local body_kern = ""
+local body_user = ""
+
+src_kern:write("#include <sys_kern.h>\n")
+src_user:write("#include <sys_user.h>\n\n")
+
+local function process_line(line)
+	if line == "" or line:sub(1, 1) == "\t" then
+		return
+	end
+
+	local f, t = line:find("[%w_]+%(")
+
+	if not f then
+		return
+	end
+
+	local start, mid, fin = line:sub(1, f-1), line:sub(f, t-1), line:sub(t)
+
+	if mid == "__attribute__" or mid == "link" then
+		return
+	end
+
+	local decl = start .. "(*" .. mid .. ")" .. fin .. "\n"
+
+	hdr_user:write("extern " .. decl)
+	src_user:write(decl)
+
+	body_kern = body_kern .. "\tcalltable[" .. count .. "] = &" .. mid .. ";\n"
+	body_user = body_user .. "\t" .. mid .. " = calltable[" .. count .. "];\n"
+
+	count = count + 1
+
+	return true
+end
+
+while true do
+	local line = hdr_kern:read()
+
+	if not line then
+		break
+	end
+
+	if not process_line(line) then
+		hdr_user:write(line .. "\n")
+	end
+end
+
+local function write_link(f, content)
+	f:write("\nvoid link()\n{\n")
+	f:write("\tvoid **calltable = " .. calltable .. ";\n\n")
+	f:write(content)
+	f:write("}\n")
+end
+
+write_link(src_kern, body_kern)
+write_link(src_user, body_user)
+
+hdr_kern:close()
+hdr_user:close()
+src_kern:close()
+src_user:close()
diff --git a/stage3/fut/os b/stage3/fut/os
new file mode 100644
index 0000000..64d627f
--- /dev/null
+++ b/stage3/fut/os
@@ -0,0 +1,161 @@
+gfx
+	- modes text, pixel
+	- different buffers
+	- switch between them manually or thingily
+
+- similar to tmux
+- hierarchy
+
+- text input channel
+- keyboard input channel
+- mouse input channel
+
+- text output channel
+	-
+- graphics output channel
+
+- add text?
+- scrollback?
+
+init
+
+copy
+remove
+move
+list
+edit
+directory
+
+shell
+terminal
+
+mouse
+keyboard
+text
+
+tiler
+desktop
+
+--
+
+process, display, channel
+
+--
+
+display.x
+display.y
+display.width
+display.height
+display.index
+display.parent
+
+display = current_display()
+display = create_display(x, y, width, height)
+
+add_display(parent, child, -1)
+remove_display(parent, child)
+
+display.set_char(pos, color, text)
+display.set_pixel(pos, color)
+display.flush()
+
+channel = create_channel()
+add_channel(display, channel, name)
+channel = get_channel(display, name)
+
+--
+
+process = create_process(path, display)
+
+add_channel(process, channel)
+get_channel(process, "signal")
+get_channel(process, "status")
+
+--
+
+current_process()
+	.get_channel("status")
+	.send(finish)
+
+--
+void main()
+{
+	current_display()
+		.get_channel("text")
+		.send("hello, world\n");
+}
+
+--
+
+append(string self, string other)
+{
+	self.grow(other.len())
+	memcpy(self.ptr + self.len() - other.len(), other.ptr, other.len())
+}
+
+--
+string get_line(channel input)
+{
+	string s = "";
+
+	loop {
+		string c = input.recv();
+
+		if (c[0] == '\n')
+			break;
+
+		s.append(c);
+	}
+
+	return s;
+}
+
+--
+void main()
+{
+	channel input = current_display()
+		.get_channel("keyboard");
+
+	loop {
+		string command = get_line(input);
+
+		process proc = create_process(path, current_display());
+
+		receiver status = proc
+			.get_channel("status")
+			.subscribe();
+
+		proc.start();
+
+		while (!status.recv().equal("finish"))
+			yield();
+	}
+}
+
+--
+void main()
+{
+
+}
+
+-- channels
+void send(channel c, value v)
+{
+	listener l = c.listeners.pop();
+
+	if (l) {
+		listener.resume(v)
+	} else {
+		for (s in c.subscribers) {
+			if (s.active)
+				s.active.resume(v)
+			else
+				s.buffer.append(v)
+		}
+	}
+}
+
+-- queue
+
+- runqueue pointer at fixed address
+- processes must free all heap allocated memory before exit
diff --git a/stage3/fut/process.c b/stage3/fut/process.c
new file mode 100644
index 0000000..ea99ccf
--- /dev/null
+++ b/stage3/fut/process.c
@@ -0,0 +1,77 @@
+#define STACK_SIZE 65536
+#define CURRENT *((process *) 0x500)
+
+process process_current()
+{
+	return CURRENT;
+}
+
+static void process_delete(process p)
+{
+	free(p->stack);
+	free(p->code);
+	map_clear(&p->channels);
+}
+
+static void process_push(process p, u64 value)
+{
+	p->stack_ptr -= sizeof value;
+	*p->stack_ptr = value;
+}
+
+void process_exit()
+{
+	if (CURRENT->next == CURRENT)
+		panic("init exited");
+
+	CURRENT->prev->next = CURRENT->next;
+	CURRENT->next->prev = CURRENT->prev;
+	rc_drop(*current);
+
+	process_yield();
+}
+
+process process_create(char *path, display d)
+{
+	process p = rc_create(sizeof *p, &process_delete);
+
+	p->state = PROCESS_CREATED;
+
+	p->stack = malloc(STACK_SIZE);
+	p->stack_ptr = p->stack + STACK_SIZE;
+	p->code = p->code_ptr = file_read(path);
+
+	process_push(p, (u64) &process_exit);
+	// push 6 callee resaved registers - contents dont actually matter.
+	for (int i = 0; i < 6; i++)
+		process_push(p, 0);
+
+	p->displ = d;
+	p->next = p->prev = nil;
+	map_init(&p->channels);
+
+	channel sig = channel_create();
+	process_channel_add(p, "signal", sig);
+	rc_drop(sig);
+
+	channel stat = channel_create();
+	process_channel_add(p, "status", stat);
+	rc_drop(stat);
+
+	return p;
+}
+
+void process_start(process p)
+{
+	if (p->code_ptr == nil)
+		panic("attempt to start invalid process");
+
+	if (p->state != PROCESS_CREATED)
+		panic("attempt to start running or dead process");
+
+	rc_grab(p);
+
+	p->next = CURRENT->next;
+	CURRENT->next = p;
+	p->prev = CURRENT;
+}
diff --git a/stage3/fut/sys_kern.c b/stage3/fut/sys_kern.c
new file mode 100644
index 0000000..c7c5fcc
--- /dev/null
+++ b/stage3/fut/sys_kern.c
@@ -0,0 +1,21 @@
+#include <sys_kern.h>
+
+void link()
+{
+	void **calltable = 0x500;
+
+	calltable[0] = &display_current;
+	calltable[1] = &display_create;
+	calltable[2] = &display_add;
+	calltable[3] = &display_remove;
+	calltable[4] = &display_pixel;
+	calltable[5] = &display_channel_add;
+	calltable[6] = &display_channel_get;
+	calltable[7] = &rc_grab;
+	calltable[8] = &rc_drop;
+	calltable[9] = &rc_create;
+	calltable[10] = &weak_downgrade;
+	calltable[11] = &weak_upgrade;
+	calltable[12] = &weak_drop;
+	calltable[13] = &channel_create;
+}
diff --git a/stage3/fut/sys_kern.h b/stage3/fut/sys_kern.h
new file mode 100644
index 0000000..083fce3
--- /dev/null
+++ b/stage3/fut/sys_kern.h
@@ -0,0 +1,91 @@
+#ifndef _SYS_H_
+#define _SYS_H_
+
+// misc
+
+typedef struct {
+	i32 x, y;
+} pos;
+
+typedef struct {
+	u32 width, height;
+} bounds;
+
+typedef struct {
+	u8 r, g, b
+} color;
+
+// display
+
+typedef struct display {
+	pos p;
+	bounds b;
+	struct display *parent;
+	u64 index;
+} *display;
+
+display display_current();
+display display_create();
+void display_add(display parent, display child, i32 index);
+void display_remove(display child);
+
+void display_pixel(display d, pos p, color c);
+
+void display_channel_add(char *name, channel ch);
+channel display_channel_get(char *name);
+
+// rc
+
+typedef struct __attribute__((packed)) {
+	u32 ref;
+	u32 own;
+	void *data;
+	void (*delete)(void *data);
+} rc_header;
+
+void rc_grab(void *rc);
+void rc_drop(void *rc);
+
+void *rc_create(u64 siz, void *delete);
+void *weak_downgrade(void *rc);
+void *weak_upgrade(void *weak)
+void weak_drop(void *weak);
+
+// channel
+
+typedef struct {
+	array listeners;
+	array subscribers;
+} *channel;
+
+channel channel_create();
+
+// buffered
+
+typedef struct {
+	void *active;
+	array buffer;
+} buffered;
+
+// process
+
+typedef struct process __attribute__((packed)) {
+	void *code;
+	void *stack;
+	u64 *stack_ptr;
+	struct process *next;
+	struct process *prev;
+	map channels;
+	display displ;
+	enum {
+		PROCESS_CREATED,
+		PROCESS_RUNNING,
+		PROCESS_DEAD,
+	} state;
+} *process;
+
+// setup pointers
+
+void link();
+
+#endif
diff --git a/stage3/fut/sys_user.c b/stage3/fut/sys_user.c
new file mode 100644
index 0000000..4490513
--- /dev/null
+++ b/stage3/fut/sys_user.c
@@ -0,0 +1,36 @@
+#include <sys_user.h>
+
+display (*display_current)();
+display (*display_create)();
+void (*display_add)(display parent, display child, i32 index);
+void (*display_remove)(display child);
+void (*display_pixel)(display d, pos p, color c);
+void (*display_channel_add)(char *name, channel ch);
+channel (*display_channel_get)(char *name);
+void (*rc_grab)(void *rc);
+void (*rc_drop)(void *rc);
+void *(*rc_create)(u64 siz, void *delete);
+void *(*weak_downgrade)(void *rc);
+void *(*weak_upgrade)(void *weak)
+void (*weak_drop)(void *weak);
+channel (*channel_create)();
+
+void link()
+{
+	void **calltable = 0x500;
+
+	display_current = calltable[0];
+	display_create = calltable[1];
+	display_add = calltable[2];
+	display_remove = calltable[3];
+	display_pixel = calltable[4];
+	display_channel_add = calltable[5];
+	display_channel_get = calltable[6];
+	rc_grab = calltable[7];
+	rc_drop = calltable[8];
+	rc_create = calltable[9];
+	weak_downgrade = calltable[10];
+	weak_upgrade = calltable[11];
+	weak_drop = calltable[12];
+	channel_create = calltable[13];
+}
diff --git a/stage3/fut/sys_user.h b/stage3/fut/sys_user.h
new file mode 100644
index 0000000..3be3d58
--- /dev/null
+++ b/stage3/fut/sys_user.h
@@ -0,0 +1,91 @@
+#ifndef _SYS_H_
+#define _SYS_H_
+
+// misc
+
+typedef struct {
+	i32 x, y;
+} pos;
+
+typedef struct {
+	u32 width, height;
+} bounds;
+
+typedef struct {
+	u8 r, g, b
+} color;
+
+// display
+
+typedef struct display {
+	pos p;
+	bounds b;
+	struct display *parent;
+	u64 index;
+} *display;
+
+extern display (*display_current)();
+extern display (*display_create)();
+extern void (*display_add)(display parent, display child, i32 index);
+extern void (*display_remove)(display child);
+
+extern void (*display_pixel)(display d, pos p, color c);
+
+extern void (*display_channel_add)(char *name, channel ch);
+extern channel (*display_channel_get)(char *name);
+
+// rc
+
+typedef struct __attribute__((packed)) {
+	u32 ref;
+	u32 own;
+	void *data;
+	void (*delete)(void *data);
+} rc_header;
+
+extern void (*rc_grab)(void *rc);
+extern void (*rc_drop)(void *rc);
+
+extern void *(*rc_create)(u64 siz, void *delete);
+extern void *(*weak_downgrade)(void *rc);
+extern void *(*weak_upgrade)(void *weak)
+extern void (*weak_drop)(void *weak);
+
+// channel
+
+typedef struct {
+	array listeners;
+	array subscribers;
+} *channel;
+
+extern channel (*channel_create)();
+
+// buffered
+
+typedef struct {
+	void *active;
+	array buffer;
+} buffered;
+
+// process
+
+typedef struct process __attribute__((packed)) {
+	void *code;
+	void *stack;
+	u64 *stack_ptr;
+	struct process *next;
+	struct process *prev;
+	map channels;
+	display displ;
+	enum {
+		PROCESS_CREATED,
+		PROCESS_RUNNING,
+		PROCESS_DEAD,
+	} state;
+} *process;
+
+// setup pointers
+
+void link();
+
+#endif
diff --git a/stage3/fut/yield.asm b/stage3/fut/yield.asm
new file mode 100644
index 0000000..0c4a134
--- /dev/null
+++ b/stage3/fut/yield.asm
@@ -0,0 +1,49 @@
+global process_yield
+extern rc_drop
+
+%define CURRENT [0x500]
+
+section .text
+process_yield:
+	; save callee reserved regs to old stack
+	push rbx
+	push rbp
+	push r12
+	push r13
+	push r14
+	push r15
+
+	; get CURRENT
+	mov rdi, CURRENT
+
+	; set CURRENT->stack_ptr
+	mov rax, rdi
+	add rax, 16
+	mov [rax], rsp
+
+	; switch to new process
+	add rax, 8
+	mov rbx, [rax]
+	mov CURRENT, rbx
+
+	; activate new stack
+	add rbx, 16
+	mov rsp, [rbx]
+
+	; drop old process (=rdi)
+	call rc_drop
+
+	; grab new process
+	mov rdi, CURRENT
+	call rc_grab
+
+	; restore callee reserved registers
+	pop r15
+	pop r14
+	pop r13
+	pop r12
+	pop rbp
+	pop rbx
+
+	; jump into new process, with style
+	ret
diff --git a/stage3/gfx.c b/stage3/gfx.c
new file mode 100644
index 0000000..0ecf423
--- /dev/null
+++ b/stage3/gfx.c
@@ -0,0 +1,32 @@
+#include "gfx.h"
+
+struct GfxInfo *gfxinfo = (void *) (0x1000-10);
+
+// byteswap
+u32 make_color(color col)
+{
+	return ((u32) 0)
+		& ((u32) col.r << 0)
+		& ((u32) col.g << 8)
+		& ((u32) col.b << 16)
+		& ((u32) col.a << 24);
+}
+
+void set_pixel(u16 x, u16 y, u32 col)
+{
+	*((u32 *) (u64) (gfxinfo->framebuffer + y * gfxinfo->pitch + x * sizeof col)) = col;
+}
+
+void set_region(u16 x, u16 y, u16 w, u16 h, u32 col)
+{
+	void *cbeg = (void *) (u64) (gfxinfo->framebuffer + y * gfxinfo->pitch + x * sizeof col);
+	void *cend = cbeg + h * gfxinfo->pitch;
+
+	for (; cbeg < cend; cbeg += gfxinfo->pitch) {
+		void *rbeg = cbeg;
+		void *rend = rbeg + w * sizeof col;
+
+		for (; rbeg < rend; rbeg += sizeof col)
+			*((u32 *) rbeg) = col;
+	}
+}
diff --git a/stage3/gfx.h b/stage3/gfx.h
new file mode 100644
index 0000000..e4e5d8b
--- /dev/null
+++ b/stage3/gfx.h
@@ -0,0 +1,21 @@
+#ifndef _GFX_H_
+#define _GFX_H_
+
+#include "def.h"
+
+extern struct __attribute__((packed)) GfxInfo {
+	u16 pitch;
+	u16 width;
+	u16 height;
+	u32 framebuffer;
+} *gfxinfo;
+
+typedef struct {
+	u8 r, g, b, a;
+} color;
+
+u32 make_color(color col);
+void set_pixel(u16 x, u16 y, u32 col);
+void set_region(u16 x, u16 y, u16 w, u16 h, u32 col);
+
+#endif
diff --git a/stage3/halt.c b/stage3/halt.c
new file mode 100644
index 0000000..63ad8e2
--- /dev/null
+++ b/stage3/halt.c
@@ -0,0 +1,7 @@
+#include "halt.h"
+
+void halt()
+{
+	for (;;)
+		;
+}
diff --git a/stage3/halt.h b/stage3/halt.h
new file mode 100644
index 0000000..9521dd9
--- /dev/null
+++ b/stage3/halt.h
@@ -0,0 +1,6 @@
+#ifndef _HALT_H_
+#define _HALT_H_
+
+void halt();
+
+#endif
diff --git a/stage3/main.c b/stage3/main.c
new file mode 100644
index 0000000..7c84d05
--- /dev/null
+++ b/stage3/main.c
@@ -0,0 +1,34 @@
+#include "paging.h"
+#include "def.h"
+#include "gfx.h"
+#include "halt.h"
+
+void clear_screen(); // framebuffer.asm
+
+void kmain()
+{
+	clear_screen();
+
+	for (MemRegion *mmap = (void *) 0x500; mmap->start != nil; mmap++)
+		page_region(mmap);
+
+	page_region(&(MemRegion) {
+		.start = (void *) (u64) gfxinfo->framebuffer,
+		.size = gfxinfo->pitch * gfxinfo->height,
+		.type = MEM_RESERVED,
+		.zero = 0,
+	});
+
+	/*
+	for (u16 x = 0; x < gfxinfo->width; x++)
+	for (u16 y = 0; y < gfxinfo->height; y++)
+		set_pixel(x, y, 0x0087CEEB);
+	*/
+
+	set_region(0, 0, gfxinfo->width, gfxinfo->height, 0x0087CEEB);
+
+	halt();
+}
+
+// 0xE0000000
+// 0xE03E8000
diff --git a/stage3/memory.asm b/stage3/memory.asm
new file mode 100644
index 0000000..b4410a3
--- /dev/null
+++ b/stage3/memory.asm
@@ -0,0 +1,59 @@
+global memcpy, memmove
+
+section .text
+
+memcpy:
+.bulk_copy:
+	cmp rdx, 8
+	jl .bytewise_copy
+	mov rax, qword[rsi]
+	mov qword[rdi], rax
+	sub rdx, 8
+	add rdi, 8
+	add rsi, 8
+.bytewise_copy:
+	cmp rdx, 0
+	je .return
+	mov al, byte[rsi]
+	mov byte[rdi], al
+	dec rdx
+	inc rdi
+	inc rsi
+	jmp .bytewise_copy
+.return:
+	ret
+
+memmove:
+	mov rcx, rdx
+.bulk_read:
+	cmp rdx, 8
+	jl .bytewise_read
+	push qword[rsi]
+	add rsi, 8
+	sub rdx, 8
+	jmp .bulk_read
+.bytewise_read:
+	cmp rdx, 0
+	je .bulk_write
+	dec rsp
+	mov al, byte[rsi]
+	mov byte[rsp], al
+	inc rsi
+	dec rdx
+	jmp .bytewise_read
+.bulk_write:
+	cmp rcx, 8
+	jl .bytewise_write
+	pop qword[rdi]
+	add rdi, 8
+	sub rcx, 8
+.bytewise_write:
+	cmp rcx, 0
+	je .return
+	mov al, byte[rsp]
+	mov byte[rdi], al
+	inc rsp
+	inc rdi
+	dec rcx
+.return:
+	ret
diff --git a/stage3/paging.asm b/stage3/paging.asm
new file mode 100644
index 0000000..8b1d571
--- /dev/null
+++ b/stage3/paging.asm
@@ -0,0 +1,336 @@
+global page_region
+extern print_hex, print_chr, newline, print_dec, print_str
+
+section .text
+
+pagebuf_init:
+	.start: dq 0x5000
+	.size: dq 0x2000
+	.used: dq 0
+
+pagebuf: dq pagebuf_init
+
+next_page: dq 0
+
+; allocate new page table buffer
+alloc:
+	; rsi = buffer (result)
+	; rdi = next_page
+	; r8  = pagebuf
+	; rbx = upper
+	; rax = tmp; used_next
+
+	mov r8, [pagebuf] ; *pagebuf
+	mov rsi, [r8]     ; start = pagebuf->start
+
+	mov rbx, [r8+8]   ; size = pagebuf->size
+	add rbx, rsi      ; upper_have = start + size
+
+	; round *up* to 0x1000 align
+	mov rax, 0xfff
+	add rsi, rax
+	not rax
+	and rsi, rax      ; aligned_start = (start + 0xfff) & (~0xfff)
+
+	mov rax, [r8+16]  ; used = pagebuf->used
+	add rax, 0x1000
+	add rsi, rax      ; upper_need = aligned_start + used + 0x1000
+
+	cmp rsi, rbx      ; if upper_need > upper_have
+	ja .newbuf        ; current region is full, get new
+
+	cmp rsi, r10      ; if upper_need >= next_page
+	jae .oom          ; out of memory (target buffer isn't paged yet)
+
+	mov [r8+16], rax  ; pagebuf->used = used + 0x1000
+
+	; clear out buffer
+
+	mov rbx, rsi
+	sub rsi, 0x1000
+
+.clear:
+	sub rbx, 8
+	mov qword[rbx], 0
+	cmp rbx, rsi
+	jne .clear
+
+	ret
+
+; select next page buffer
+.newbuf:
+	cmp r8, pagebuf_init
+	jne .nextbuf
+
+	mov r8, 0x500
+	jmp .trybuf
+
+.nextbuf:
+	add r8, 24
+
+.trybuf:
+	cmp qword[r8], 0
+	je .oom       ; last region reached
+
+	mov rax, [r8+16]
+
+	cmp rax, -1
+	je .nextbuf   ; region is reserved
+
+	cmp rax, 0
+	jne .oom      ; region has not been paged yet
+
+	mov [pagebuf], r8
+	jmp alloc
+
+.oom:
+	push rdi
+
+	mov rdi, .oom_msg
+	call print_str
+
+	pop rdi
+
+	call print_hex
+	call newline
+
+	jmp $
+
+.oom_msg: db "out of memory for page table", 10, "next_page = ", 0
+
+; get/create page tables
+get_tables:
+; level 4
+
+	; rdi = address         (arg, persist)
+	; rax = tmp
+	; rbx = mask
+	; rcx = bits            (persist)
+	; rdx = level           (persist)
+	; r8  = table address
+	; rsi = next offset     (persist)
+
+	mov cl, 12+9*4
+	mov dl, 4
+
+	mov rsi, 0x1000
+
+; level 4
+.level:
+	dec dl
+	mov r8, rdi
+	mov rbx, -1           ; reset remainder mask
+	shl rbx, cl           ; update remainder mask
+	not rbx               ; negate remainder mask
+	and r8, rbx           ; apply remainder mask
+
+	mov al, 9
+	mul dl
+	add al, 12
+	mov cl, al
+
+	shr r8, cl            ; divide
+	shl r8, 3             ; multiply by 8
+
+	mov rbx, 0xfff        ; 0x1000 alignment
+	not rbx               ; offset mask
+
+	and rsi, rbx          ; apply offset mask
+	add r8, rsi           ; add offset
+	push r8               ; store
+
+	cmp dl, 0
+	je .done
+
+	mov rsi, [r8]         ; next offset
+	cmp rsi, 0
+	jne .level
+
+	call alloc
+	or rsi, 3
+	mov r8, [rsp]
+	mov [r8], rsi
+
+	jmp .level
+
+.done:
+	pop r11
+	pop r12
+	pop r13
+	pop r14
+
+	ret
+
+space:
+	mov dil, ' '
+	jmp print_chr
+
+page_region:
+	push rbx
+	push r12
+	push r13
+	push r14
+	push r15
+
+	mov r9, rdi
+
+	mov rdi, [r9]   ; ptr = mmap_entry->ptr
+	mov r10, [next_page]
+
+	push rdi
+
+	mov rax, 1 << 63
+
+	or rdi, rax
+	call print_hex
+	call space
+
+	mov rdi, [r9+8]
+	add rdi, [rsp]
+	or rdi, rax
+
+	call print_hex
+	call newline
+
+	pop rdi
+
+	; for   usable region (type = 1), set mmap_entry->used =  0
+	; for reserved region (type = 2), set mmap_entry->used = -1
+	xor rax, rax
+	xor rbx, rbx
+	mov eax, dword[r9+16]
+	cmp rax, 1
+	je .set_used
+	dec rbx
+.set_used:
+	mov [r9+16], rbx
+
+	mov r10, rdi
+	mov r15, rdi    ; r15 = end of region
+	add r15, [r9+8]
+
+	mov rax, 0xfff
+	not rax
+	and rdi, rax    ; round down to 0x1000 aligned
+
+	cmp rdi, r10
+	jb .get_tables
+
+	mov r10, rdi
+
+.get_tables:
+	call get_tables ; page tables into r11-r14
+
+	; start filling L1 map
+.l1:
+	mov rax, rdi
+	or rax, 3
+	mov [r11], rax
+
+	add rdi, 0x1000
+
+	cmp rdi, r10
+	jb .next
+
+	mov r10, rdi
+
+.next:
+	cmp rdi, r15    ; if next >= end
+	jae .done
+
+	; prepare rcx mask for later
+	mov rcx, -1
+	shl rcx, 3
+
+	; bump L1
+
+	add r11, 8
+	mov rax, r11
+	and rax, 0xfff
+	jnz .l1
+
+	; bump L2
+
+	add r12, 8
+	mov rax, r12
+	and rax, 0xfff
+	jnz .l2
+
+	; bump L3
+
+	add r13, 8
+	mov rax, r13
+	and rax, 0xfff
+	jnz .l3
+
+	; bump L4
+
+	add r14, 8
+	mov rax, r14
+	and rax, 0xfff
+	jnz .l4
+
+	; machine has more than 256TB of RAM, tell user to fuck off
+	jmp .bruh
+
+.l4:
+	mov r13, [r14]
+	and r13, rcx
+	jnz .l3
+
+	call alloc
+	mov r13, rsi
+	or rsi, 3
+	mov [r14], rsi
+
+.l3:
+	mov r12, [r13]
+	and r12, rcx
+	jnz .l2
+
+	call alloc
+	mov r12, rsi
+	or rsi, 3
+	mov [r13], rsi
+
+.l2:
+	mov r11, [r12]
+	and r11, rcx
+	jnz .l2
+
+	call alloc
+	mov r11, rsi
+	or rsi, 3
+	mov [r12], rsi
+
+	jmp .l1
+
+.done:
+	mov [next_page], r10
+
+	pop r15
+	pop r14
+	pop r13
+	pop r12
+	pop rbx
+
+	ret
+
+.bruh:
+	mov rdi, .bruh_msg
+	call print_str
+	jmp $
+
+.bruh_msg: db "bruh why do you have more than 256TB of RAM (you fucking glow)", 10, 0
+
+; identity map available memory
+old_page_map:
+	mov r9, 0x0500                ; mmap_entry
+.entry:
+	cmp qword[r9], 0
+	je .done
+	call page_region
+	add r9, 24
+	jmp .entry
+.done:
+	ret
diff --git a/stage3/paging.h b/stage3/paging.h
new file mode 100644
index 0000000..b9a3930
--- /dev/null
+++ b/stage3/paging.h
@@ -0,0 +1,20 @@
+#ifndef _PAGING_H_
+#define _PAGING_H_
+
+#include "def.h"
+
+typedef enum {
+	MEM_USABLE = 1,
+	MEM_RESERVED = 2,
+} MemRegionType;
+
+typedef struct __attribute__((packed)) {
+	void *start;
+	usize size;
+	u16 type;
+	u16 zero;
+} MemRegion;
+
+void page_region(MemRegion *region);
+
+#endif