;
; MenuesOS Boot Loader
;
; Author: Trans
; Date: 14.02.03
; Version: 1.0
;
; Current Version: 1.1
; Date of modification: 11.06.03
;
; Compile with FASM
;
;--------Code------------
org 100h
start:
push cs
pop ds
mov ax,0003h
int 10h
mov dx,title
call print
mov dx,mes1
call print
mov dx,img0
call file_open
test ax,ax
jnz loader_continue
mov dx,img2
call file_open
test ax,ax
jne loader_continue
mov dx,img3
call file_open
test ax,ax
je loader_not_find_file
loader_continue:
mov [handle],ax
;---------Read boot-sector-----------
mov bx,ax
mov dx,buffer
mov cx,512
call file_read
;--------Read parametrs--------------
mov ax,[buffer+0bh]
mov [SectSize],ax
mov al,[buffer+0dh]
mov [ClustSect],al
mov ax,[buffer+0eh]
mov [ResSect],ax
add ax,[ResRgn]
mov [FATRgn],ax
mov al,[buffer+10h]
mov [FATCnt],al
xor bx,bx
mov bl,al
mov ax,[buffer+11h]
mov [RootEnt],ax
shr ax,4 ; ax=ax*32/512
mov [RootDirRgnSz],ax
mov ax,[buffer+16h]
mov [FATSect],ax
mul bx
mov [FATRgnSz],ax
add ax,[FATRgn]
mov [RootDirRgn],ax
add ax,[RootDirRgnSz]
mov [DataRgn],ax
;------Read FATs and RootDir---------
xor eax,eax
xor edx,edx
mov ax,[FATRgn]
mul [SectSize]
mov cx,dx
mov dx,ax
mov bx,[handle]
call file_offset
mov ax,[FATRgnSz]
mul [SectSize]
mov cx,ax
mov dx,buffer
mov bx,[handle]
call file_read
mov cx,[RootEnt]
shl cx,5
mov dx,Root
mov bx,[handle]
call file_read
;-------Search entry pointer in RootDir---------
push ds
pop es
mov cx,[RootEnt]
mov bx,Root
loader_loc_00:
push cx
mov cx,11
mov di,bx
mov si,kernel
repe cmpsb
jnz loader_notfound
pop cx
jmp loader_find
loader_notfound:
pop cx
add bx,32
loop loader_loc_00
loader_find:
mov ax,[bx+1ah]
mov [FirstClust],ax
mov eax,[bx+1ch]
mov [filesize],eax
;------Read Kernel----------------------
call read_kernel
;---------------------------------------
mov bx,[handle]
call file_close
;;;;;;;;;;;;;;;;;;;;;;
jmp loader_yes
;;;;;;;;;;;;;;;;;;;;;;
; mov dx,mes2
; call print
;loader_key:
; mov ah,00h
; int 16h
; cmp al,1bh ;ESC
; je loader_no
; cmp al,6eh ;'n'
; je loader_no
; cmp al,4eh ;'N'
; je loader_no
; cmp al,79h ;'y'
; je loader_yes
; cmp al,59h ;'Y'
; je loader_yes
; jmp loader_key
loader_not_find_file:
mov dx,mes4
call print
jmp loader_exit
loader_yes:
mov dx,yes
call print
mov ax,7000h
mov es,ax
mov si,move_kernel
xor di,di
mov cx,len_mk
rep movsb
jmp far 7000h:0000h
; jmp loader_exit
loader_no:
mov dx,no
call print
loader_exit:
mov dx,mes3
call print
retn
;----Subprogramms--------
print:
; in: dx - offset of ASCII string
; out:
mov ah,09h
int 21h
retn
file_open:
; in: ds:dx - offset of ASCIIZ filename string
; out: ax - file handle (ax=0 - not found)
mov ax,3d00h
int 21h
jnc fo_exit
xor ax,ax
fo_exit:
retn
file_close:
; in: bx - file handle
; out:
mov ah,3eh
int 21h
retn
file_read:
; in: bx - file handle
; ds:dx - buffer
; cx - numbers of bytes
; out:
mov ah,3fh
int 21h
retn
file_offset:
; in: bx - file handle
; cx:dx - offset in bytes (cx*65535+dx)
; out:
mov ax,4200h
int 21h
retn
sector_find:
; in: ax - No of Cluster
; out: ax - 1st sector of Cluster
dec ax
dec ax
push bx
xor bx,bx
mov bl,[ClustSect]
mul bx
pop bx
add ax,[DataRgn]
retn
read_cluster:
; in: ax - No of Cluster
; ds:dx - buffer
; out:
push dx
call sector_find
push ax
xor eax,eax
xor ebx,ebx
pop ax
mov bx,[SectSize]
mul ebx
mov dx,ax
shr eax,16
mov cx,ax
mov bx,[handle]
call file_offset
xor ax,ax
mov al,[ClustSect]
mul [SectSize]
mov cx,ax
mov bx,[handle]
pop dx
call file_read
retn
read_kernel:
; in:
; out:
mov ax,8000h
mov es,ax ;8000:0000 = 80000h - Temporal location of kernel
xor di,di ;
mov ax,[FirstClust]
mov bp,ax
rk_loc_00:
push es
mov dx,Root
call read_cluster
xor ax,ax ; Moving cluster to area of location kernel
mov al,[ClustSect] ;
mul [SectSize] ;
mov cx,ax ;
pop es ;
mov si,Root ;
rep movsb ;
cmp di,00h
jne rk_continue
mov ax,es
add ax,1000h
mov es,ax
rk_continue:
mov ax,bp
cmp ax,0ff8h
jae rk_done
shl ax,1 ; Val=Clustrer*1,5 //(Cluster*3)/2
add ax,bp ;
shr ax,1 ;
mov bx,ax
add bx,buffer
mov ax,[bx]
bt bp,0
jc rk_nechet
and ax,0fffh
jmp rk_chet
rk_nechet:
shr ax,4
rk_chet:
mov bp,ax
jmp rk_loc_00
rk_done:
retn
move_kernel:
; in:
; out:
mov ax,8000h
mov ds,ax
mov ax,1000h
mov es,ax
xor si,si
xor di,di
mov cx,8000h
rep movsb
mov cx,8000h
rep movsb
mov bx,es
add bx,1000h
mov es,bx
mov bx,ds
add bx,1000h
mov ds,bx
mov cx,8000h
rep movsb
mov cx,8000h
rep movsb
mov ax,1000h
mov ds,ax
mov es,ax
jmp far 1000h:0000h
retn
len_mk=$-move_kernel
;--------Data------------
title db 'MenuetOS/KolibriOS Boot Loader. Ver.1.1 Copyright(C) 2003, Trans.',0ah,0dh,0ah,0dh,'$'
mes1 db 'It is alternative of boot from floppy.',0ah,0dh
db 'You MUST select HD booting !!!',0ah,0dh,0ah,0dh,'$'
mes2 db 'Are you sure loading KolibriOS? (Y/N):','$'
yes db 'Y','$'
no db 'N','$'
mes3 db 0ah,0dh,0ah,0dh,'See you later ...',0ah,0dh,'$'
mes4 db 0ah,0dh,0ah,0dh,'Not Found: '
img0 db 'kolibri\kolibri.img',0,', '
img2 db 'kolibri.img',0,', '
img3 db 'menuet.img',0,' :($'
kernel db 'KERNEL MNT',0
handle dw ?
SectSize dw ? ; +0bh
ClustSect db ? ; +0dh
ResSect dw ? ; +0eh
FATCnt db ? ; +10h
RootEnt dw ? ; +11h
FATSect dw ? ; +16h
filesize dd ? ; +1ch
FirstClust dw ? ; +1ah
ResRgn dw 0 ; = VolumeStart
FATRgn dw ? ; = ResRgn+ResSect
RootDirRgn dw ? ; = FATRgn+(FATCnt*FATSect)
DataRgn dw ? ; = RootDirRgn+((RootEnt*32)/SectSize)
ResRgnSz dw ? ; = ResSect
FATRgnSz dw ? ; = FATCnt*FATSect
RootDirRgnSz dw ? ; = (RootEnt*32)/SectSize
;First sector of cluster N = DataRgn+((N-2)*ClustSect)
buffer:
org 3000h
Root: