about summary refs log blame commit diff stats
path: root/cbtech.lisp
blob: 15eda5a9c50180dd12c66d69f68afd71d83aa882 (plain) (tree) 
628c87c ^


















1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18


















                                                                                 
(require "ccmd")
(require "cbuiltins")
(defpackage #:cbtech
  (:use #:common-lisp #:ccmd #:cbuiltins)
  (:export
    #:main))
(in-package #:cbtech)
;; Favour symbols & objects over C-like numbers
(defconstant +cmds+ (list
                      (create-tab #'bt-quit "QUIT" 1)
                      (create-tab #'help "help" 2)
                      (create-tab #'look "look" 2)))
(defun main ()
  (format *standard-output* "> ")
  (let* ((tab (lookup (parse (read-line)) +cmds+))
         (f (fun tab)))
    (funcall f)))                       ; I *think* this is better than (flet ...
(provide "cbtech")
generated by cgit-pink 1.4.1-2-gfad0 (git 2.36.2.497.gbbea4dcf42) at 2024-06-26 18:57:22 +0000
or: #008800; background-color: #fff0ff } /* Literal.String.Regex */ .highlight .s1 { color: #dd2200; background-color: #fff0f0 } /* Literal.String.Single */ .highlight .ss { color: #aa6600; background-color: #fff0f0 } /* Literal.String.Symbol */ .highlight .bp { color: #003388 } /* Name.Builtin.Pseudo */ .highlight .fm { color: #0066bb; font-weight: bold } /* Name.Function.Magic */ .highlight .vc { color: #336699 } /* Name.Variable.Class */ .highlight .vg { color: #dd7700 } /* Name.Variable.Global */ .highlight .vi { color: #3333bb } /* Name.Variable.Instance */ .highlight .vm { color: #336699 } /* Name.Variable.Magic */ .highlight .il { color: #0000DD; font-weight: bold } /* Literal.Number.Integer.Long */
# Methods for constructing buffered-file objects.
#
# TODO: There are hard-coded parameters here for buffer sizes. When they
# overflow, tracking down what's going on can get hairy.
#
# HACK: buffered-file stores naked addrs. This is safe because buffered-file
# objects are opaque. But still sub-optimal; they'll be harder to reclaim when
# we get around to that.

== code

open:  # filename: (addr array byte), write?: boolean, out: (addr handle buffered-file)
    # . prologue
    55/push-ebp
    89/<- %ebp 4/r32/esp
    # . save registers
    50/push-eax
    51/push-ecx
    # var new-fd/ecx: fd
    (open-fd *(ebp+8) *(ebp+0xc))  # => eax
    89/<- %ecx 0/r32/eax
    # if fd < 0 return
    3d/compare-eax-with 0/imm32
    7c/jump-if-< $open:end/disp8
    # allocate a buffered-file
    (allocate Heap 0x1010 *(ebp+0x10))  # file-buffer-size + 16 for other fields
    # var out-addr/eax: (addr buffered-file)
    8b/-> *(ebp+0x10) 0/r32/eax
    (lookup *eax *(eax+4))  # => eax
    # out-addr->size = 4KB
    c7 0/subop/copy *(eax+0xc) 0x1000/imm32/file-buffer-size  # Stream-size + 4 for fd
    # out-addr->fd = fd
    89/<- *eax 1/r32/ecx
$open:end:
    # . restore registers
    59/pop-to-ecx
    58/pop-to-eax
    # . epilogue
    89/<- %esp 5/r32/ebp
    5d/pop-to-ebp
    c3/return

open-fd:  # filename: (addr array byte), write?: boolean -> result/eax: fd
    # . prologue
    55/push-ebp
    89/<- %ebp 4/r32/esp
    # . save registers
    51/push-ecx
    52/push-edx
    53/push-ebx
    56/push-esi
    # ecx = filename
    8b/-> *(ebp+8) 1/r32/ecx
    # var size/edx: int = filename->length + 1 for the trailing null character
    8b/-> *ecx 2/r32/edx
    42/increment-edx
    # var s/esi: (stream size)
    29/subtract-from %esp 2/r32/edx
    52/push-edx  # size
    68/push 0/imm32/read
    68/push 0/imm32/write
    89/<- %esi 4/r32/esp
    # copy filename and a final null character
    (clear-stream %esi)
    (write %esi %ecx)
    # spill edx
    52/push-edx
    # var fd/eax: fd = open(filename)
    8d/copy-address *(esi+0xc) 3/r32/ebx
    8b/-> *(ebp+0xc) 1/r32/ecx/flags
    ba/copy-to-edx 0x180/imm32/permissions
    e8/call syscall_open/disp32
    # restore edx
    5a/pop-to-edx
$open-fd:end:
    # . reclaim locals
    01/add-to %esp 2/r32/edx
    81 0/subop/add %esp 0xc/imm32
    # . restore registers
    5e/pop-to-esi
    5b/pop-to-ebx
    5a/pop-to-edx
    59/pop-to-ecx
    # . epilogue
    89/<- %esp 5/r32/ebp
    5d/pop-to-ebp
    c3/return

populate-buffered-file-containing:  # contents: (addr array byte), out: (addr handle buffered-file)
    # . prologue
    55/push-ebp
    89/<- %ebp 4/r32/esp
    # . save registers
    50/push-eax
    51/push-ecx
    56/push-esi
    57/push-edi
    # esi = contents
    8b/-> *(ebp+8) 6/r32/esi
    # var n/ecx: int = len(contents)
    8b/-> *esi 1/r32/ecx
    # var stream/edi: (handle stream byte)
    68/push 0/imm32
    68/push 0/imm32
    89/<- %edi 4/r32/esp
    # allocate stream
    (new-stream Heap %ecx 1 %edi)
    # var stream-addr/edi: (addr stream byte) = lookup(stream)
    (lookup *edi *(edi+4))  # => eax
    89/<- %edi 0/r32/eax
    # write contents to stream
    (write %edi %esi)
    # allocate buffered-file
    (allocate Heap 0x110 *(ebp+0xc))
    # var out-addr/eax: (addr buffered-file)
    8b/-> *(ebp+0xc) 0/r32/eax
    (lookup *eax *(eax+4))  # => eax
    # out-addr->size = 256 bytes
    c7 0/subop/copy *(eax+0xc) 0x100/imm32/file-buffer-size
    # out-addr->fd = stream
    89/<- *eax 7/r32/edi
$populate-buffered-file-containing:end:
    # . reclaim locals
    81 0/subop/add %esp 8/imm32
    # . restore registers
    5f/pop-to-edi
    5e/pop-to-esi
    59/pop-to-ecx
    58/pop-to-eax
    # . epilogue
    89/<- %esp 5/r32/ebp
    5d/pop-to-ebp
    c3/return

new-buffered-file:  # out: (addr handle buffered-file)
    # . prologue
    55/push-ebp
    89/<- %ebp 4/r32/esp
    # . save registers
    50/push-eax
    51/push-ecx
    # var stream/ecx: (handle stream byte)
    68/push 0/imm32
    68/push 0/imm32
    89/<- %ecx 4/r32/esp
    # allocate stream
    (new-stream Heap 0x100 1 %ecx)
    # var stream-addr/ecx: (addr stream byte) = lookup(stream)
    (lookup *ecx *(ecx+4))  # => eax
    89/<- %ecx 0/r32/eax
    # allocate buffered-file
    (allocate Heap 0x110 *(ebp+8))
    # var out-addr/eax: (addr buffered-file)
    8b/-> *(ebp+8) 0/r32/eax
    (lookup *eax *(eax+4))  # => eax
    # out-addr->size = 256 bytes
    c7 0/subop/copy *(eax+0xc) 0x100/imm32/file-buffer-size
    # out-addr->fd = stream
    89/<- *eax 1/r32/ecx
$new-buffered-file:end:
    # . reclaim locals
    81 0/subop/add %esp 8/imm32
    # . restore registers
    59/pop-to-ecx
    58/pop-to-eax
    # . epilogue
    89/<- %esp 5/r32/ebp
    5d/pop-to-ebp
    c3/return
generated by cgit-pink 1.4.1-2-gfad0 (git 2.36.2.497.gbbea4dcf42) at 2024-06-26 18:57:21 +0000