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-rw-r--r--ldlinux.asm337
1 files changed, 11 insertions, 326 deletions
diff --git a/ldlinux.asm b/ldlinux.asm
index d81353b5..73803308 100644
--- a/ldlinux.asm
+++ b/ldlinux.asm
@@ -144,6 +144,7 @@ ClustPerMoby resd 1 ; Clusters per 64K
ClustSize resd 1 ; Bytes/cluster
KernelName resb 12 ; Mangled name for kernel
; (note the spare byte after!)
+OrigKernelExt resd 1 ; Original kernel extension
FBytes equ $ ; Used by open/getc
FBytes1 resw 1
FBytes2 resw 1
@@ -1028,325 +1029,12 @@ mkkeymap: stosb
mov di,syslinux_cfg
call open
jz no_config_file
-;
-; Now we have the config file open
-;
- call parse_config ; Parse configuration file
-no_config_file:
-;
-; Check whether or not we are supposed to display the boot prompt.
-;
-check_for_key:
- cmp word [ForcePrompt],byte 0 ; Force prompt?
- jnz enter_command
- test byte [KbdFlags],5Bh ; Caps, Scroll, Shift, Alt
- jz auto_boot ; If neither, default boot
-
-enter_command:
- mov si,boot_prompt
- call cwritestr
-
- mov byte [FuncFlag],0 ; <Ctrl-F> not pressed
- mov di,command_line
-;
-; get the very first character -- we can either time
-; out, or receive a character press at this time. Some dorky BIOSes stuff
-; a return in the buffer on bootup, so wipe the keyboard buffer first.
-;
-clear_buffer: mov ah,1 ; Check for pending char
- int 16h
- jz get_char_time
- xor ax,ax ; Get char
- int 16h
- jmp short clear_buffer
-get_char_time:
- call vgashowcursor
- mov cx,[KbdTimeOut]
- and cx,cx
- jz get_char ; Timeout == 0 -> no timeout
- inc cx ; The first loop will happen
- ; immediately as we don't
- ; know the appropriate DX value
-time_loop: push cx
-tick_loop: push dx
- call pollchar
- jnz get_char_pop
- xor ax,ax
- int 1Ah ; Get time "of day"
- pop ax
- cmp dx,ax ; Has the timer advanced?
- je tick_loop
- pop cx
- loop time_loop ; If so, decrement counter
- call vgahidecursor
- jmp command_done ; Timeout!
-
-get_char_pop: pop eax ; Clear stack
-get_char:
- call vgashowcursor
- call getchar
- call vgahidecursor
- and al,al
- jz func_key
-
-got_ascii: cmp al,7Fh ; <DEL> == <BS>
- je backspace
- cmp al,' ' ; ASCII?
- jb not_ascii
- ja enter_char
- cmp di,command_line ; Space must not be first
- je get_char
-enter_char: test byte [FuncFlag],1
- jz .not_ctrl_f
- mov byte [FuncFlag],0
- cmp al,'0'
- jb .not_ctrl_f
- je ctrl_f_0
- cmp al,'9'
- jbe ctrl_f
-.not_ctrl_f: cmp di,max_cmd_len+command_line ; Check there's space
- jnb get_char
- stosb ; Save it
- call writechr ; Echo to screen
-get_char_2: jmp short get_char
-not_ascii: mov byte [FuncFlag],0
- cmp al,0Dh ; Enter
- je command_done
- cmp al,06h ; <Ctrl-F>
- je set_func_flag
- cmp al,08h ; Backspace
- jne get_char
-backspace: cmp di,command_line ; Make sure there is anything
- je get_char ; to erase
- dec di ; Unstore one character
- mov si,wipe_char ; and erase it from the screen
- call cwritestr
- jmp short get_char_2
-
-set_func_flag:
- mov byte [FuncFlag],1
- jmp short get_char_2
-ctrl_f_0: add al,10 ; <Ctrl-F>0 == F10
-ctrl_f: push di
- sub al,'1'
- xor ah,ah
- jmp short show_help
-
-func_key:
- ; AL = 0 if we get here
- push di
- cmp ah,68 ; F10
- ja get_char_2
- sub ah,59 ; F1
- jb get_char_2
- xchg al,ah
-show_help: ; AX = func key # (0 = F1, 9 = F10)
- shl ax,FILENAME_MAX_LG2 ; Convert to pointer
- xchg di,ax
- add di,FKeyName
- cmp byte [di],NULLFILE
- je get_char_2 ; Undefined F-key
- call searchdir
- jz fk_nofile
- push si
- call crlf
- pop si
- call get_msg_file
- jmp short fk_wrcmd
-fk_nofile:
- call crlf
-fk_wrcmd:
- mov si,boot_prompt
- call cwritestr
- pop di ; Command line write pointer
- push di
- mov byte [di],0 ; Null-terminate command line
- mov si,command_line
- call cwritestr ; Write command line so far
- pop di
- jmp short get_char_2
-auto_boot:
- mov si,default_cmd
- mov di,command_line
- mov cx,(max_cmd_len+4) >> 2
- rep movsd
- jmp short load_kernel
-command_done:
- call crlf
- cmp di,command_line ; Did we just hit return?
- je auto_boot
- xor al,al ; Store a final null
- stosb
-
-load_kernel: ; Load the kernel now
-;
-; First we need to mangle the kernel name the way DOS would...
-;
- mov si,command_line
- mov di,KernelName
- push si
- push di
- call mangle_name
- pop di
- pop si
-;
-; Fast-forward to first option (we start over from the beginning, since
-; mangle_name doesn't necessarily return a consistent ending state.)
-;
-clin_non_wsp: lodsb
- cmp al,' '
- ja clin_non_wsp
-clin_is_wsp: and al,al
- jz clin_opt_ptr
- lodsb
- cmp al,' '
- jbe clin_is_wsp
-clin_opt_ptr: dec si ; Point to first nonblank
- mov [CmdOptPtr],si ; Save ptr to first option
-;
-; Now check if it is a "virtual kernel"
;
- mov cx,[VKernelCtr]
- push ds
- push word vk_seg
- pop ds
- cmp cx,byte 0
- je not_vk
- xor si,si ; Point to first vkernel
-vk_check: pusha
- mov cx,11
- repe cmpsb ; Is this it?
- je vk_found
- popa
- add si,vk_size
- loop vk_check
-not_vk: pop ds
-;
-; Not a "virtual kernel" - check that's OK and construct the command line
-;
- cmp word [AllowImplicit],byte 0
- je bad_implicit
- push es
- push si
- push di
- mov di,real_mode_seg
- mov es,di
- mov si,AppendBuf
- mov di,cmd_line_here
- mov cx,[AppendLen]
- rep movsb
- mov [CmdLinePtr],di
- pop di
- pop si
- pop es
- mov bx,exten_count << 2 ; Alternates to try
-;
-; Find the kernel on disk
-;
-get_kernel: mov byte [KernelName+11],0 ; Zero-terminate filename/extension
- mov eax,[KernelName+8] ; Save initial extension
- mov [OrigKernelExt],eax
-.search_loop: push bx
- mov di,KernelName ; Search on disk
- call searchdir
- pop bx
- jnz kernel_good
- mov eax,[exten_table+bx] ; Try a different extension
- mov [KernelName+8],eax
- sub bx,byte 4
- jnb .search_loop
-bad_kernel:
- mov si,KernelName
- mov di,KernelCName
- push di
- call unmangle_name ; Get human form
- mov si,err_notfound ; Complain about missing kernel
- call cwritestr
- pop si ; KernelCName
- call cwritestr
- mov si,crlf_msg
- jmp abort_load ; Ask user for clue
+; Now we have the config file open. Parse the config file and
+; run the user interface.
;
-; bad_implicit: The user entered a nonvirtual kernel name, with "implicit 0"
-;
-bad_implicit: mov si,KernelName ; For the error message
- mov di,KernelCName
- call unmangle_name
- jmp short bad_kernel
-;
-; vk_found: We *are* using a "virtual kernel"
-;
-vk_found: popa
- push di
- mov di,VKernelBuf
- mov cx,vk_size >> 2
- rep movsd
- push es ; Restore old DS
- pop ds
- push es
- push word real_mode_seg
- pop es
- mov di,cmd_line_here
- mov si,VKernelBuf+vk_append
- mov cx,[VKernelBuf+vk_appendlen]
- rep movsb
- mov [CmdLinePtr],di ; Where to add rest of cmd
- pop es
- pop di ; DI -> KernelName
- push di
- mov si,VKernelBuf+vk_rname
- mov cx,11 ; We need ECX == CX later
- rep movsb
- pop di
- xor bx,bx ; Try only one version
- jmp get_kernel
-;
-; kernel_corrupt: Called if the kernel file does not seem healthy
-;
-kernel_corrupt: mov si,err_notkernel
- jmp abort_load
-;
-; This is it! We have a name (and location on the disk)... let's load
-; that sucker!! First we have to decide what kind of file this is; base
-; that decision on the file extension. The following extensions are
-; recognized:
-;
-; .com - COMBOOT image
-; .cbt - COMBOOT image
-; .c32 - COM32 image
-; .bs - Boot sector
-; .0 - PXE bootstrap program (PXELINUX only)
-; .bin - Boot sector
-; .bss - Boot sector, but transfer over DOS superblock (SYSLINUX only)
-; .img - Floppy image (ISOLINUX only)
-;
-; Anything else is assumed to be a Linux kernel.
-;
-kernel_good:
- pusha
- mov si,KernelName
- mov di,KernelCName
- call unmangle_name ; Get human form
- sub di,KernelCName
- mov [KernelCNameLen],di
- popa
-
- mov ecx,[KernelName+8] ; Get (mangled) extension
- and ecx,00ffffffh ; 3 bytes only
- cmp ecx,'COM'
- je is_comboot_image
- cmp ecx,'CBT'
- je is_comboot_image
- cmp ecx,'C32'
- je is_com32_image
- cmp ecx,'BS '
- je is_bootsector
- cmp ecx,'BIN'
- je is_bootsector
- cmp ecx,'BSS'
- je is_bss_sector
- ; Otherwise Linux kernel
+%include "ui.inc"
;
; Linux kernel loading code is common.
@@ -1699,20 +1387,17 @@ initrd_cmd_len equ 7
; Config file keyword table
;
%include "keywords.inc"
+
;
-; Extensions to search for (in *reverse* order). Note that the last
-; (lexically first) entry in the table is a placeholder for the original
-; extension, needed for error messages. The exten_table is shifted so
-; the table is 1-based; this is because a "loop" cx is used as index.
+; Extensions to search for (in *forward* order).
;
-exten_table:
-OrigKernelExt: dd 0 ; Original extension
- db 'COM',0 ; COMBOOT (same as DOS)
- db 'BS ',0 ; Boot Sector
+exten_table: db 'CBT',0 ; COMBOOT (specific)
db 'BSS',0 ; Boot Sector (add superblock)
- db 'CBT',0 ; COMBOOT (specific)
+ db 'BS ',0 ; Boot Sector
+ db 'COM',0 ; COMBOOT (same as DOS)
+exten_table_end:
+ dd 0, 0 ; Need 8 null bytes here
-exten_count equ (($-exten_table) >> 2) - 1 ; Number of alternates
;
; Misc initialized (data) variables
;