* Unify the command-line handling and extension-scanning codesyslinux-2.00-pre10

* Fix bug relating to '/' characters in ISOLINUX
* Add <Ctrl-V> to display the version number

6 files changed, 443 insertions, 1033 deletions

diff --git a/NEWS b/NEWS
index 89c4ca2e..1c483dd8 100644
--- a/NEWS
+++ b/NEWS
@@ -4,13 +4,18 @@ apply to that specific program only; other changes apply to both.
 Changes in 2.00:
 	* ALL: Add support for "COM32" (32-bit COMBOOT) images.
 	* ALL: Add an API for COMBOOT/COM32 images.  See comboot.doc
-	  for details.
+	  for details.  There is a C development environment for
+	  COM32 being created; it should be ready at some point in
+	  the future.
 	* Fix mbr.asm so that it actually works.
 	* SYSLINUX: The syslinux installer *SHOULD* now be safe to
 	  run setuid root.
 	* PXELINUX: Fix bug where PXELINUX would override random
 	  chunks of the UNDI code segment!  Thanks to Kevin Tran for
 	  finding this bug.
+	* ISOLINUX: Fix a bug related to slashes in pathnames.
+	* ALL: Make the <Ctrl-V> key print out the version; this is
+	  to help debugging.
 
 Changes in 1.76:
 	* ISOLINUX: Remove code no longer used which caused hangs on
diff --git a/bootsect.inc b/bootsect.inc
index d3e50fc9..b114c4eb 100644
--- a/bootsect.inc
+++ b/bootsect.inc
@@ -108,7 +108,7 @@ load_bootsec:
 		jmp bcopy_over_self
 
 %if IS_SYSLINUX = 0
-is_bss_image:
+is_bss_sector:
 		mov si,err_bssimage
 		call cwritestr
 		jmp enter_command
diff --git a/isolinux.asm b/isolinux.asm
index ce2520c5..7966f9ea 100644
--- a/isolinux.asm
+++ b/isolinux.asm
@@ -838,359 +838,10 @@ load_config:
 %endif
 
 ;
-; Now we have the config file open
+; Now we have the config file open.  Parse the config file and
+; run the user interface.
 ;
-		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
-		mov dx,[BIOS_timer]		; 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,FILENAME_MAX
-		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
-;
-; Find the kernel on disk
-;
-get_kernel:     mov byte [KernelName+FILENAME_MAX],0	; Zero-terminate filename/extension
-		mov di,KernelName
-		xor al,al
-		mov cx,FILENAME_MAX-5		; Need 4 chars + null
-		repne scasb			; Scan for final null
-		jne .no_skip
-		dec di				; Point to final null 
-.no_skip:	mov [KernelExtPtr],di
-		mov bx,exten_table
-.search_loop:	push bx
-                mov di,KernelName	      	; Search on disk
-                call searchdir
-		pop bx
-                jnz kernel_good
-		mov eax,[bx]			; Try a different extension
-		mov si,[KernelExtPtr]
-		mov [si],eax
-		mov byte [si+4],0
-		add bx,byte 4
-		cmp bx,exten_table_end
-		jna .search_loop		; allow == case (final case)
-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
-;
-; 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,FILENAME_MAX		; We need ECX == CX later
-		rep movsb
-		pop di
-		xor bx,bx			; Try only one version
-
-		; Is this a "localboot" pseudo-kernel?
-		cmp byte [VKernelBuf+vk_rname], 0
-		jne get_kernel		; No, it's real, go get it
-
-		mov ax, [VKernelBuf+vk_rname+1]
-		jmp local_boot
-;
-; 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; case insensitive:
-;
-; .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
-		sub di,KernelCName
-		mov [KernelCNameLen],di
-		popa
-		
-		push di
-		push ax
-		mov di,KernelName
-		xor al,al
-		mov cx,FILENAME_MAX
-		repne scasb
-		jne .one_step
-		dec di
-.one_step:	mov ecx,[di-4]			; 4 bytes before end
-		pop ax
-		pop di
-
-;
-; At this point, DX:AX contains the size of the kernel, and SI contains
-; the file handle/cluster pointer.
-;
-		or ecx,20202000h		; Force lower case
-
-		cmp ecx,'.com'
-		je is_comboot_image
-		cmp ecx,'.cbt'
-		je is_comboot_image
-		cmp ecx,'.c32'
-		je is_com32_image
-		cmp ecx,'.img'
-		je is_disk_image
-		cmp ecx,'.bss'
-		je is_bss_image
-		cmp ecx,'.bin'
-		je is_bootsector
-		shr ecx,8
-		cmp ecx,'.bs'
-		je is_bootsector
-		shr ecx,8
-		cmp cx,'.0'
-		je is_bootsector
-		; Otherwise Linux kernel
+%include "ui.inc"
 
 ;
 ; Linux kernel loading code is common.
@@ -1476,8 +1127,11 @@ searchdir_iso:
 		mov [di-1],byte 0		; Terminate at directory name
 		mov cl,02h			; Search for directory
 		xchg cl,[ISOFlags]
-		push di
+
+		push di				; Save these...
 		push cx
+
+		; Create recursion stack frame...
 		push word .resume		; Where to "return" to
 		push es
 .isfile:	xchg ax,di
@@ -1554,6 +1208,7 @@ searchdir_iso:
 		xchg edx,eax			; Directory length in edx
 		pop cx				; Old ISOFlags
 		pop di				; Next filename pointer
+		mov byte [di-1], '/'		; Restore slash
 		mov [ISOFlags],cl		; Restore the flags
 		jz .failure			; Did we fail?  If so fail for real!
 		jmp .look_for_slash		; Otherwise, next level
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
 ;
diff --git a/pxelinux.asm b/pxelinux.asm
index e4572b88..7df0bc7c 100644
--- a/pxelinux.asm
+++ b/pxelinux.asm
@@ -772,364 +772,15 @@ config_scan:
 
 		jmp no_config_file
 
-;
-; Now we have the config file open
-;
 .success:	add sp,byte 16			; Adjust stack
-		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
-		mov dx,[BIOS_timer]		; 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,FILENAME_MAX
-		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
-;
-; Find the kernel on disk
-;
-get_kernel:     mov byte [KernelName+FILENAME_MAX],0	; Zero-terminate filename/extension
-		mov di,KernelName
-		xor al,al
-		mov cx,FILENAME_MAX-5		; Need 4 chars + null
-		repne scasb			; Scan for final null
-		jne .no_skip
-		dec di				; Point to final null 
-.no_skip:	mov [KernelExtPtr],di
-		mov bx,exten_table
-.search_loop:	push bx
-                mov di,KernelName	      	; Search on disk
-                call searchdir
-		pop bx
-                jnz kernel_good
-		mov eax,[bx]			; Try a different extension
-		mov si,[KernelExtPtr]
-		mov [si],eax
-		mov byte [si+4],0
-		add bx,byte 4
-		cmp bx,exten_table_end
-		jna .search_loop		; allow == case (final case)
-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
-;
-; 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,FILENAME_MAX		; We need ECX == CX later
-		rep movsb
-		pop di
-		mov al,[VKernelBuf+vk_ipappend]
-		mov [IPAppend],al
-		xor bx,bx			; Try only one version
 
-		; Is this a "localboot" pseudo-kernel?
-		cmp byte [VKernelBuf+vk_rname], 0
-		jne get_kernel		; No, it's real, go get it
-
-		mov ax, [VKernelBuf+vk_rname+1]
-		jmp local_boot
-;
-; 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; case insensitive:
 ;
-; .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)
+; Now we have the config file open.  Parse the config file and
+; run the user interface.
 ;
-; Boot sectors are currently not supported by PXELINUX.
-;
-; Anything else is assumed to be a Linux kernel.
-;
-kernel_good:
-		pusha
-		mov si,KernelName
-		mov di,KernelCName
-		call unmangle_name
-		sub di,KernelCName
-		mov [KernelCNameLen],di
-		popa
-		
-		push di
-		push ax
-		mov di,KernelName
-		xor al,al
-		mov cx,FILENAME_MAX
-		repne scasb
-		jne .one_step
-		dec di
-.one_step:	mov ecx,[di-4]			; 4 bytes before end
-		pop ax
-		pop di
+%include "ui.inc"
 
 ;
-; At this point, DX:AX contains the size of the kernel, and SI contains
-; the file handle/cluster pointer.
-;
-		or ecx,20202000h		; Force lower case
-
-		cmp ecx,'.com'
-		je is_comboot_image
-		cmp ecx,'.cbt'
-		je is_comboot_image
-		cmp ecx,'.c32'
-		je is_com32_image
-		cmp ecx,'.bss'
-		je is_bss_image
-		cmp ecx,'.bin'
-		je is_bootsector
-		shr ecx,8
-		cmp ecx,'.bs'
-		je is_bootsector
-		shr ecx,8
-		cmp cx,'.0'
-		je is_bootsector
-		; Otherwise Linux kernel
-;
 ; Linux kernel loading code is common.  However, we need to define
 ; a couple of helper macros...
 ;
diff --git a/ui.inc b/ui.inc
new file mode 100644
index 00000000..c8d309d6
--- /dev/null
+++ b/ui.inc
@@ -0,0 +1,414 @@
+;; $Id$
+;; -----------------------------------------------------------------------
+;;   
+;;   Copyright 1994-2002 H. Peter Anvin - All Rights Reserved
+;;
+;;   This program is free software; you can redistribute it and/or modify
+;;   it under the terms of the GNU General Public License as published by
+;;   the Free Software Foundation, Inc., 53 Temple Place Ste 330,
+;;   Bostom MA 02111-1307, USA; either version 2 of the License, or
+;;   (at your option) any later version; incorporated herein by reference.
+;;
+;; -----------------------------------------------------------------------
+
+;
+; This file should be entered with the config file open (for getc)
+;
+		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
+		mov dx,[BIOS_timer]		; 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 short 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 short get_char
+		stosb				; Save it
+		call writechr			; Echo to screen
+		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,16h			; <Ctrl-V>
+		je print_version
+		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
+get_char_2:
+		jmp short get_char
+
+ctrl_f_0:	add al,10			; <Ctrl-F>0 == F10
+ctrl_f:		sub al,'1'
+		xor ah,ah
+		jmp short show_help
+
+func_key:
+		; AL = 0 if we get here
+		xchg al,ah
+		cmp al,68			; F10
+		ja short get_char_2
+		sub al,59			; F1
+		jb short get_char_2
+show_help:	; AX = func key # (0 = F1, 9 = F10)
+		push di				; Save end-of-cmdline pointer
+		shl ax,FILENAME_MAX_LG2		; Convert to pointer
+		add ax,FKeyName
+		xchg di,ax
+		cmp byte [di],NULLFILE
+		je short fk_nofile		; Undefined F-key
+		call searchdir
+		jz short fk_nofile		; File not found
+		push si
+		call crlf
+		pop si
+		call get_msg_file
+		jmp short fk_wrcmd
+
+print_version:
+		push di				; Command line write pointer
+		mov si,syslinux_banner
+		call cwritestr
+		mov si,copyright_str
+		call cwritestr
+
+		; ... fall through ...
+
+		; Write the boot prompt and command line again and
+		; wait for input.  Note that this expects the cursor
+		; to already have been CRLF'd, and that the old value
+		; of DI (the command line write pointer) is on the stack.
+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
+fk_nofile:	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,FILENAME_MAX
+		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
+;
+; Find the kernel on disk
+;
+get_kernel:     mov byte [KernelName+FILENAME_MAX],0	; Zero-terminate filename/extension
+%if IS_SYSLINUX		; SYSLINUX has to deal with DOS mangled names...
+		mov eax,[KernelName+8]		; Save initial extension
+		mov [exten_table_end],eax	; Last case == initial ext.
+%else
+		mov di,KernelName
+		xor al,al
+		mov cx,FILENAME_MAX-5		; Need 4 chars + null
+		repne scasb			; Scan for final null
+		jne .no_skip
+		dec di				; Point to final null 
+.no_skip:	mov [KernelExtPtr],di
+%endif
+		mov bx,exten_table
+.search_loop:	push bx
+                mov di,KernelName	      	; Search on disk
+                call searchdir
+		pop bx
+                jnz kernel_good
+		mov eax,[bx]			; Try a different extension
+%if IS_SYSLINUX
+		mov [KernelName+8],eax
+%else
+		mov si,[KernelExtPtr]
+		mov [si],eax
+		mov byte [si+4],0
+%endif
+		add bx,byte 4
+		cmp bx,exten_table_end
+		jna .search_loop		; allow == case (final case)
+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
+;
+; 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,FILENAME_MAX		; We need ECX == CX later
+		rep movsb
+		pop di
+%if IS_PXELINUX
+		mov al,[VKernelBuf+vk_ipappend]
+		mov [IPAppend],al
+%endif
+		xor bx,bx			; Try only one version
+
+%if IS_SYSLINUX
+		jmp get_kernel
+%else
+		; Is this a "localboot" pseudo-kernel?
+		cmp byte [VKernelBuf+vk_rname], 0
+		jne get_kernel		; No, it's real, go get it
+
+		mov ax, [VKernelBuf+vk_rname+1]
+		jmp local_boot
+%endif
+
+;
+; 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; case insensitive:
+;
+; .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
+		sub di,KernelCName
+		mov [KernelCNameLen],di
+		popa
+		
+%if IS_SYSLINUX
+		mov ecx,[KernelName+7]
+		mov cl,'.'
+%else
+		push di
+		push ax
+		mov di,KernelName
+		xor al,al
+		mov cx,FILENAME_MAX
+		repne scasb
+		jne .one_step
+		dec di
+.one_step:	mov ecx,[di-4]			; 4 bytes before end
+		pop ax
+		pop di
+%endif
+
+;
+; At this point, DX:AX contains the size of the kernel, and SI contains
+; the file handle/cluster pointer.
+;
+		or ecx,20202000h		; Force lower case
+
+		cmp ecx,'.com'
+		je is_comboot_image
+		cmp ecx,'.cbt'
+		je is_comboot_image
+		cmp ecx,'.c32'
+		je is_com32_image
+%if IS_ISOLINUX
+		cmp ecx,'.img'
+		je is_disk_image
+%endif
+		cmp ecx,'.bss'
+		je is_bss_sector
+		cmp ecx,'.bin'
+		je is_bootsector
+%if IS_SYSLINUX
+		cmp ecx,'.bs '
+		je is_bootsector
+		cmp ecx,'.0  '
+		je is_bootsector
+%else
+		shr ecx,8
+		cmp ecx,'.bs'
+		je is_bootsector
+		shr ecx,8
+		cmp cx,'.0'
+		je is_bootsector
+%endif
+		; Otherwise Linux kernel
+