# Experimental Mu shell
# A Lisp with indent-sensitivity and infix.
fn main screen: (addr screen), keyboard: (addr keyboard), data-disk: (addr disk) {
var globals-storage: global-table
var globals/edi: (addr global-table) <- address globals-storage
initialize-globals globals
var sandbox-storage: sandbox
var sandbox/esi: (addr sandbox) <- address sandbox-storage
initialize-sandbox sandbox, 1/with-screen
load-state data-disk, sandbox, globals
$main:loop: {
# globals layout: 1 char padding, 41 code, 1 padding, 41 code, 1 padding = 85
# sandbox layout: 1 padding, 41 code, 1 padding = 43
# total = 128 chars
render-globals screen, globals
render-sandbox screen, sandbox, 0x55/sandbox-left-margin, 0/sandbox-top-margin, 0x80/screen-width, 0x2f/screen-height-without-menu
{
var key/eax: byte <- read-key keyboard
compare key, 0
loop-if-=
# ctrl-r
{
compare key, 0x12/ctrl-r
break-if-!=
var tmp/eax: (addr handle cell) <- copy 0
var nil: (handle cell)
tmp <- address nil
allocate-pair tmp
# (main 0/real-screen 0/real-keyboard)
# We're using the fact that 'screen' and 'keyboard' in this function are always 0.
var real-keyboard: (handle cell)
tmp <- address real-keyboard
allocate-keyboard tmp
# args = cons(real-keyboard, nil)
var args: (handle cell)
tmp <- address args
new-pair tmp, real-keyboard, nil
#
var real-screen: (handle cell)
tmp <- address real-screen
allocate-screen tmp
# args = cons(real-screen, args)
tmp <- address args
new-pair tmp, real-screen, *tmp
#
var main: (handle cell)
tmp <- address main
new-symbol tmp, "main"
# args = cons(main, args)
tmp <- address args
new-pair tmp, main, *tmp
# clear real screen
clear-screen screen
set-cursor-position screen, 0, 0
# run
var out: (handle cell)
var out-ah/ecx: (addr handle cell) <- address out
var trace-storage: trace
var trace/ebx: (addr trace) <- address trace-storage
initialize-trace trace, 1/only-errors, 0x10/capacity, 0/visible
evaluate tmp, out-ah, nil, globals, trace, 0/no-fake-screen, 0/no-fake-keyboard, 0/call-number
{
var tmp/eax: byte <- read-key keyboard
compare tmp, 0
loop-if-=
}
#
loop $main:loop
}
# no way to quit right now; just reboot
edit-sandbox sandbox, key, globals, data-disk, screen, 1/tweak-real-screen
}
loop
}
}
# Gotcha: some saved state may not load.
fn load-state data-disk: (addr disk), _sandbox: (addr sandbox), globals: (addr global-table) {
var sandbox/eax: (addr sandbox) <- copy _sandbox
var data-ah/eax: (addr handle gap-buffer) <- get sandbox, data
var _data/eax: (addr gap-buffer) <- lookup *data-ah
var data/esi: (addr gap-buffer) <- copy _data
# data-disk -> stream
var s-storage: (stream byte 0x1000) # space for 8/sectors
var s/ebx: (addr stream byte) <- address s-storage
draw-text-wrapping-right-then-down-from-cursor-over-full-screen 0/screen, "loading sectors from data disk", 3/fg, 0/bg
move-cursor-to-left-margin-of-next-line 0/screen
load-sectors data-disk, 0/lba, 8/sectors, s
#? draw-stream-wrapping-right-then-down-from-cursor-over-full-screen 0/screen, s, 7/fg, 0xc5/bg=blue-bg
# stream -> gap-buffer
draw-text-wrapping-right-then-down-from-cursor-over-full-screen 0/screen, "parsing", 3/fg, 0/bg
move-cursor-to-left-margin-of-next-line 0/screen
load-gap-buffer-from-stream data, s
draw-text-wrapping-right-then-down-from-cursor-over-full-screen 0/screen, " into gap buffer", 3/fg, 0/bg
move-cursor-to-left-margin-of-next-line 0/screen
clear-stream s
# read: gap-buffer -> cell
var initial-root-storage: (handle cell)
var initial-root/ecx: (addr handle cell) <- address initial-root-storage
var trace-storage: trace
var trace/edi: (addr trace) <- address trace-storage
initialize-trace trace, 1/only-errors, 0x10/capacity, 0/visible
read-cell data, initial-root, trace
draw-text-wrapping-right-then-down-from-cursor-over-full-screen 0/screen, " into s-expressions", 3/fg, 0/bg
move-cursor-to-left-margin-of-next-line 0/screen
clear-gap-buffer data
#
{
var initial-root-addr/eax: (addr cell) <- lookup *initial-root
compare initial-root-addr, 0
break-if-!=
return
}
# load globals from assoc(initial-root, 'globals)
var globals-literal-storage: (handle cell)
var globals-literal-ah/eax: (addr handle cell) <- address globals-literal-storage
new-symbol globals-literal-ah, "globals"
var globals-literal/eax: (addr cell) <- lookup *globals-literal-ah
var globals-cell-storage: (handle cell)
var globals-cell-ah/edx: (addr handle cell) <- address globals-cell-storage
clear-trace trace
lookup-symbol globals-literal, globals-cell-ah, *initial-root, 0/no-globals, trace, 0/no-screen, 0/no-keyboard
var globals-cell/eax: (addr cell) <- lookup *globals-cell-ah
{
compare globals-cell, 0
break-if-=
load-globals globals-cell-ah, globals
}
# sandbox = assoc(initial-root, 'sandbox)
draw-text-wrapping-right-then-down-from-cursor-over-full-screen 0/screen, "loading sandbox", 3/fg, 0/bg
var sandbox-literal-storage: (handle cell)
var sandbox-literal-ah/eax: (addr handle cell) <- address sandbox-literal-storage
new-symbol sandbox-literal-ah, "sandbox"
var sandbox-literal/eax: (addr cell) <- lookup *sandbox-literal-ah
var sandbox-cell-storage: (handle cell)
var sandbox-cell-ah/edx: (addr handle cell) <- address sandbox-cell-storage
clear-trace trace
lookup-symbol sandbox-literal, sandbox-cell-ah, *initial-root, 0/no-globals, trace, 0/no-screen, 0/no-keyboard
var sandbox-cell/eax: (addr cell) <- lookup *sandbox-cell-ah
{
compare sandbox-cell, 0
break-if-=
# print: cell -> stream
clear-trace trace
print-cell sandbox-cell-ah, s, trace
# stream -> gap-buffer
load-gap-buffer-from-stream data, s
}
}
# Save state as an alist of alists:
# ((globals . ((a . (fn ...))
# ...))
# (sandbox . ...))
fn store-state data-disk: (addr disk), sandbox: (addr sandbox), globals: (addr global-table) {
compare data-disk, 0/no-disk
{
break-if-!=
return
}
var stream-storage: (stream byte 0x1000) # space enough for 8/sectors
var stream/edi: (addr stream byte) <- address stream-storage
write stream, "(\n"
write-globals stream, globals
write-sandbox stream, sandbox
write stream, ")\n"
store-sectors data-disk, 0/lba, 8/sectors, stream
}