core: merge ldlinux.asm and extlinux.asm

ldlinux.asm and extlinux.asm are by now extremely similar.  Merge
them.

Signed-off-by: H. Peter Anvin <hpa@zytor.com>

4 files changed, 210 insertions, 401 deletions

diff --git a/core/comboot.inc b/core/comboot.inc
index 7c2b6e66..da3c2399 100644
--- a/core/comboot.inc
+++ b/core/comboot.inc
@@ -942,15 +942,7 @@ comapi_readdir	equ comapi_err
 ;
 ; INT 22h AX=0022h	Close directory
 ;
-%if IS_SYSLINUX
-comapi_closedir:
-		mov si,P_SI
-		call close_dir
-		clc
-		ret
-%else
-comapi_closedir	equ comapi_err
-%endif
+comapi_closedir	equ comapi_close
 
 ;
 ; INT 22h AX=0023h	Query shuffler size
diff --git a/core/diskfs.inc b/core/diskfs.inc
new file mode 100644
index 00000000..603ada9b
--- /dev/null
+++ b/core/diskfs.inc
@@ -0,0 +1,207 @@
+; -*- fundamental -*- (asm-mode sucks)
+; -----------------------------------------------------------------------
+;   
+;   Copyright 1994-2009 H. Peter Anvin - All Rights Reserved
+;   Copyright 2009 Intel Corporation; author: H. Peter Anvin
+;
+;   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., 51 Franklin St, Fifth Floor,
+;   Boston MA 02110-1301, USA; either version 2 of the License, or
+;   (at your option) any later version; incorporated herein by reference.
+;
+; -----------------------------------------------------------------------
+
+;
+; diskfs.inc
+;
+; Common code for conventional disk-based filesystems
+;
+
+;
+; Some semi-configurable constants... change on your own risk.
+;
+FILENAME_MAX	equ (1 << FILENAME_MAX_LG2)	; Max mangled filename size
+NULLFILE	equ 0			; Null character == empty filename
+NULLOFFSET	equ 0			; Position in which to look
+retry_count	equ 16			; How patient are we with the disk?
+%assign HIGHMEM_SLOP 0			; Avoid this much memory near the top
+LDLINUX_MAGIC	equ 0x3eb202fe		; A random number to identify ourselves with
+
+MAX_OPEN_LG2	equ 6			; log2(Max number of open files)
+MAX_OPEN	equ (1 << MAX_OPEN_LG2)
+
+SECTOR_SHIFT	equ 9
+SECTOR_SIZE	equ (1 << SECTOR_SHIFT)
+
+;
+; The following structure is used for "virtual kernels"; i.e. LILO-style
+; option labels.  The options we permit here are `kernel' and `append
+; Since there is no room in the bottom 64K for all of these, we
+; stick them in high memory and copy them down before we need them.
+;
+		struc vkernel
+vk_vname:	resb FILENAME_MAX	; Virtual name **MUST BE FIRST!**
+vk_rname:	resb FILENAME_MAX	; Real name
+vk_appendlen:	resw 1
+vk_type:	resb 1			; Type of file
+		alignb 4
+vk_append:	resb max_cmd_len+1	; Command line
+		alignb 4
+vk_end:		equ $			; Should be <= vk_size
+		endstruc
+
+
+
+; ---------------------------------------------------------------------------
+;   BEGIN CODE
+; ---------------------------------------------------------------------------
+
+;
+; Memory below this point is reserved for the BIOS and the MBR
+;
+		section .earlybss
+		global trackbuf
+trackbufsize	equ 8192
+trackbuf	resb trackbufsize	; Track buffer goes here
+		; ends at 2800h
+
+		section .bss16
+		alignb 16
+		global Files
+Files		resb MAX_OPEN*16  ; 16 == open_file_t_size
+
+;
+; Common bootstrap code for disk-based derivatives
+;
+%include "diskstart.inc"
+
+
+;
+; Now, everything is "up and running"... patch kaboom for more
+; verbosity and using the full screen system
+;
+		; E9 = JMP NEAR
+		mov di,kaboom.patch
+		mov al,0e9h
+		stosb
+		mov ax,kaboom2-2
+		sub ax,di
+		stosw
+
+;
+; Now we're all set to start with our *real* business.	First load the
+; configuration file (if any) and parse it.
+;
+; In previous versions I avoided using 32-bit registers because of a
+; rumour some BIOSes clobbered the upper half of 32-bit registers at
+; random.  I figure, though, that if there are any of those still left
+; they probably won't be trying to install Linux on them...
+;
+; The code is still ripe with 16-bitisms, though.  Not worth the hassle
+; to take'm out.  In fact, we may want to put them back if we're going
+; to boot ELKS at some point.
+;
+
+;
+; Load configuration file
+;
+		pm_call load_config
+		jz no_config_file
+
+;
+; Now we have the config file open.  Parse the config file and
+; run the user interface.
+;
+%include "ui.inc"
+
+
+;
+; unmangle_name: Does the opposite of mangle_name; converts a DOS-mangled
+;                filename to the conventional representation.  This is needed
+;                for the BOOT_IMAGE= parameter for the kernel.
+;
+;                DS:SI -> input mangled file name
+;                ES:DI -> output buffer
+;
+;                On return, DI points to the first byte after the output name,
+;                which is set to a null byte.
+;
+unmangle_name:	call strcpy
+		dec di				; Point to final null byte
+		ret
+
+;
+;
+; kaboom2: once everything is loaded, replace the part of kaboom
+;	   starting with "kaboom.patch" with this part
+
+kaboom2:
+		mov si,err_bootfailed
+		call writestr
+		cmp byte [kaboom.again+1],18h	; INT 18h version?
+		je .int18
+		call getchar
+		call vgaclearmode
+		int 19h			; And try once more to boot...
+.norge:		jmp short .norge	; If int 19h returned; this is the end
+.int18:
+		call vgaclearmode
+		int 18h
+.noreg:		jmp short .noreg	; Nynorsk
+
+; -----------------------------------------------------------------------------
+;  Common modules
+; -----------------------------------------------------------------------------
+
+%include "common.inc"		; Universal modules
+%include "plaincon.inc"		; writechr
+%include "writestr.inc"		; String output
+%include "writehex.inc"		; Hexadecimal output
+%include "localboot.inc"	; Disk-based local boot
+
+; -----------------------------------------------------------------------------
+;  Begin data section
+; -----------------------------------------------------------------------------
+
+		section .data16
+copyright_str   db ' Copyright (C) 1994-'
+		asciidec YEAR
+		db ' H. Peter Anvin et al', CR, LF, 0
+err_bootfailed	db CR, LF, 'Boot failed: please change disks and press '
+		db 'a key to continue.', CR, LF, 0
+
+;
+; Config file keyword table
+;
+%include "keywords.inc"
+
+;
+; Extensions to search for (in *forward* order).
+;
+		alignz 4
+exten_table:	db '.cbt'		; COMBOOT (specific)
+%if IS_SYSLINUX
+		db '.bss'		; Boot sector (add superblock)
+%endif
+		db '.bs', 0		; Boot sector
+		db '.com'		; COMBOOT (same as DOS)
+		db '.c32'		; COM32
+exten_table_end:
+		dd 0, 0			; Need 8 null bytes here
+
+;
+; Misc initialized (data) variables
+;
+%ifdef debug				; This code for debugging only
+debug_magic	dw 0D00Dh		; Debug code sentinel
+%endif
+
+		alignz 4
+BufSafe		dw trackbufsize/SECTOR_SIZE	; Clusters we can load into trackbuf
+BufSafeBytes	dw trackbufsize		; = how many bytes?
+%ifndef DEPEND
+%if ( trackbufsize % SECTOR_SIZE ) != 0
+%error trackbufsize must be a multiple of SECTOR_SIZE
+%endif
+%endif
diff --git a/core/extlinux.asm b/core/extlinux.asm
index 27fbc3e6..2a5526b8 100644
--- a/core/extlinux.asm
+++ b/core/extlinux.asm
@@ -23,194 +23,6 @@
 ; Some semi-configurable constants... change on your own risk.
 ;
 my_id		equ extlinux_id
-; NASM 0.98.38 croaks if these are equ's rather than macros...
 FILENAME_MAX_LG2 equ 8			; log2(Max filename size Including final null)
-FILENAME_MAX	equ (1 << FILENAME_MAX_LG2)	; Max mangled filename size
-NULLFILE	equ 0			; Null character == empty filename
-NULLOFFSET	equ 0			; Position in which to look
-retry_count	equ 16			; How patient are we with the disk?
-%assign HIGHMEM_SLOP 0			; Avoid this much memory near the top
-LDLINUX_MAGIC	equ 0x3eb202fe		; A random number to identify ourselves with
 
-MAX_OPEN_LG2	equ 6			; log2(Max number of open files)
-MAX_OPEN	equ (1 << MAX_OPEN_LG2)
-
-SECTOR_SHIFT	equ 9
-SECTOR_SIZE	equ (1 << SECTOR_SHIFT)
-
-;
-; The following structure is used for "virtual kernels"; i.e. LILO-style
-; option labels.  The options we permit here are `kernel' and `append
-; Since there is no room in the bottom 64K for all of these, we
-; stick them in high memory and copy them down before we need them.
-;
-		struc vkernel
-vk_vname:	resb FILENAME_MAX	; Virtual name **MUST BE FIRST!**
-vk_rname:	resb FILENAME_MAX	; Real name
-vk_appendlen:	resw 1
-vk_type:	resb 1			; Type of file
-		alignb 4
-vk_append:	resb max_cmd_len+1	; Command line
-		alignb 4
-vk_end:		equ $			; Should be <= vk_size
-		endstruc
-
-
-
-; ---------------------------------------------------------------------------
-;   BEGIN CODE
-; ---------------------------------------------------------------------------
-
-;
-; Memory below this point is reserved for the BIOS and the MBR
-;
-		section .earlybss
-		global trackbuf
-trackbufsize	equ 8192
-trackbuf	resb trackbufsize	; Track buffer goes here
-		; ends at 2800h
-
-		section .bss16
-		alignb 16
-		global Files
-Files		resb MAX_OPEN*16  ; 16 == open_file_t_size
-
-;
-; Common bootstrap code for disk-based derivatives
-;
-%include "diskstart.inc"
-
-
-;
-; Now, everything is "up and running"... patch kaboom for more
-; verbosity and using the full screen system
-;
-		; E9 = JMP NEAR
-		mov di,kaboom.patch
-		mov al,0e9h
-		stosb
-		mov ax,kaboom2-2
-		sub ax,di
-		stosw
-
-;
-; Now we're all set to start with our *real* business.	First load the
-; configuration file (if any) and parse it.
-;
-; In previous versions I avoided using 32-bit registers because of a
-; rumour some BIOSes clobbered the upper half of 32-bit registers at
-; random.  I figure, though, that if there are any of those still left
-; they probably won't be trying to install Linux on them...
-;
-; The code is still ripe with 16-bitisms, though.  Not worth the hassle
-; to take'm out.  In fact, we may want to put them back if we're going
-; to boot ELKS at some point.
-;
-
-;
-; Load configuration file
-;
-		pm_call load_config
-		jz no_config_file
-
-;
-; Now we have the config file open.  Parse the config file and
-; run the user interface.
-;
-%include "ui.inc"
-
-
-;
-; unmangle_name: Does the opposite of mangle_name; converts a DOS-mangled
-;                filename to the conventional representation.  This is needed
-;                for the BOOT_IMAGE= parameter for the kernel.
-;
-;                DS:SI -> input mangled file name
-;                ES:DI -> output buffer
-;
-;                On return, DI points to the first byte after the output name,
-;                which is set to a null byte.
-;
-unmangle_name:	call strcpy
-		dec di				; Point to final null byte
-		ret
-
-;
-;
-; kaboom2: once everything is loaded, replace the part of kaboom
-;	   starting with "kaboom.patch" with this part
-
-kaboom2:
-		mov si,err_bootfailed
-		call writestr
-		cmp byte [kaboom.again+1],18h	; INT 18h version?
-		je .int18
-		call getchar
-		call vgaclearmode
-		int 19h			; And try once more to boot...
-.norge:		jmp short .norge	; If int 19h returned; this is the end
-.int18:
-		call vgaclearmode
-		int 18h
-.noreg:		jmp short .noreg	; Nynorsk
-
-
-
-build_curdir_str:
-		ret
-
-; -----------------------------------------------------------------------------
-;  Common modules
-; -----------------------------------------------------------------------------
-
-%include "common.inc"		; Universal modules
-%include "plaincon.inc"		; writechr
-%include "writestr.inc"		; String output
-%include "writehex.inc"		; Hexadecimal output
-%include "strecpy.inc"          ; strcpy with end pointer check
-%include "localboot.inc"	; Disk-based local boot
-
-; -----------------------------------------------------------------------------
-;  Begin data section
-; -----------------------------------------------------------------------------
-
-		section .data16
-copyright_str   db ' Copyright (C) 1994-'
-		asciidec YEAR
-		db ' H. Peter Anvin et al', CR, LF, 0
-err_bootfailed	db CR, LF, 'Boot failed: please change disks and press '
-		db 'a key to continue.', CR, LF, 0
-config_name	db 'extlinux.conf',0		; Unmangled form
-
-;
-; Config file keyword table
-;
-%include "keywords.inc"
-
-;
-; Extensions to search for (in *forward* order).
-;
-		alignz 4
-exten_table:	db '.cbt'		; COMBOOT (specific)
-		db '.img'		; Disk image
-		db '.bs', 0		; Boot sector
-		db '.com'		; COMBOOT (same as DOS)
-		db '.c32'		; COM32
-exten_table_end:
-		dd 0, 0			; Need 8 null bytes here
-
-;
-; Misc initialized (data) variables
-;
-%ifdef debug				; This code for debugging only
-debug_magic	dw 0D00Dh		; Debug code sentinel
-%endif
-
-		alignz 4
-BufSafe		dw trackbufsize/SECTOR_SIZE	; Clusters we can load into trackbuf
-BufSafeBytes	dw trackbufsize		; = how many bytes?
-%ifndef DEPEND
-%if ( trackbufsize % SECTOR_SIZE ) != 0
-%error trackbufsize must be a multiple of SECTOR_SIZE
-%endif
-%endif
+%include "diskfs.inc"
diff --git a/core/ldlinux.asm b/core/ldlinux.asm
index 5c449044..183262a3 100644
--- a/core/ldlinux.asm
+++ b/core/ldlinux.asm
@@ -22,9 +22,7 @@
 ;
 ; ****************************************************************************
 
-%ifndef IS_MDSLINUX
 %define IS_SYSLINUX 1
-%endif
 %include "head.inc"
 
 ;
@@ -32,205 +30,5 @@
 ;
 my_id		equ syslinux_id
 FILENAME_MAX_LG2 equ 6			; log2(Max filename size Including final null)
-FILENAME_MAX	equ (1<<FILENAME_MAX_LG2) ; Max mangled filename size
-NULLFILE	equ 0			; First char space == null filename
-NULLOFFSET	equ 0			; Position in which to look
-retry_count	equ 16			; How patient are we with the disk?
-%assign HIGHMEM_SLOP 0			; Avoid this much memory near the top
-LDLINUX_MAGIC	equ 0x3eb202fe		; A random number to identify ourselves with
 
-MAX_OPEN_LG2	equ 6			; log2(Max number of open files)
-MAX_OPEN	equ (1 << MAX_OPEN_LG2)
-
-SECTOR_SHIFT	equ 9
-SECTOR_SIZE	equ (1 << SECTOR_SHIFT)
-
-
-
-;
-; The following structure is used for "virtual kernels"; i.e. LILO-style
-; option labels.  The options we permit here are `kernel' and `append
-; Since there is no room in the bottom 64K for all of these, we
-; stick them in high memory and copy them down before we need them.
-;
-		struc vkernel
-vk_vname:	resb FILENAME_MAX	; Virtual name **MUST BE FIRST!**
-vk_rname:	resb FILENAME_MAX	; Real name
-vk_appendlen:	resw 1
-vk_type:	resb 1			; Type of file
-		alignb 4
-vk_append:	resb max_cmd_len+1	; Command line
-		alignb 4
-vk_end:		equ $			; Should be <= vk_size
-		endstruc
-
-
-
-; ---------------------------------------------------------------------------
-;   BEGIN CODE
-; ---------------------------------------------------------------------------
-
-;
-; Memory below this point is reserved for the BIOS and the MBR
-;
-		section .earlybss
-trackbufsize	equ 8192
-trackbuf	resb trackbufsize	; Track buffer goes here
-		; ends at 2800h
-
-		section .bss16
-		alignb 16
-		global Files
-Files		resb MAX_OPEN*16  ; 16 == open_file_t_size
-
-;
-; Common bootstrap code for disk-based derivatives
-;
-%include "diskstart.inc"
-
-
-
-;
-; Now, everything is "up and running"... patch kaboom for more
-; verbosity and using the full screen system
-;
-		; E9 = JMP NEAR
-		mov di,kaboom.patch
-		mov al,0e9h
-		stosb
-		mov ax,kaboom2-2
-		sub ax,di
-		stosw
-
-;
-; Now we're all set to start with our *real* business.	First load the
-; configuration file (if any) and parse it.
-;
-; In previous versions I avoided using 32-bit registers because of a
-; rumour some BIOSes clobbered the upper half of 32-bit registers at
-; random.  I figure, though, that if there are any of those still left
-; they probably won't be trying to install Linux on them...
-;
-; The code is still ripe with 16-bitisms, though.  Not worth the hassle
-; to take'm out.  In fact, we may want to put them back if we're going
-; to boot ELKS at some point.
-;
-
-;
-; Load configuration file
-;
-		pm_call load_config
-		jz no_config_file
-
-;
-; Now we have the config file open.  Parse the config file and
-; run the user interface.
-;
-%include "ui.inc"
-
-		
-;
-; close_dir:
-;	     Deallocates a directory structure (pointer in SI)
-;	     Assumes CS == DS.
-;
-close_dir:
-		and si,si
-		jz .closed
-		mov dword [si],0		; First dword == file_sector
-		xor si,si
-.closed:	ret
-
-
-
-;
-;
-; kaboom2: once everything is loaded, replace the part of kaboom
-;	   starting with "kaboom.patch" with this part
-
-kaboom2:
-		mov si,err_bootfailed
-		call writestr
-		cmp byte [kaboom.again+1],18h	; INT 18h version?
-		je .int18
-		call getchar
-		call vgaclearmode
-		int 19h			; And try once more to boot...
-.norge:			jmp short .norge	; If int 19h returned; this is the end
-.int18:
-		call vgaclearmode
-		int 18h
-.noreg:	jmp short .noreg	; Nynorsk
-
-
-
-;
-; unmangle_name: Does the opposite of mangle_name; converts a DOS-mangled
-;                filename to the conventional representation.  This is needed
-;                for the BOOT_IMAGE= parameter for the kernel.
-;                NOTE: A 13-byte buffer is mandatory, even if the string is
-;                known to be shorter.
-;
-;                DS:SI -> input mangled file name
-;                ES:DI -> output buffer
-;
-;                On return, DI points to the first byte after the output name,
-;                which is set to a null byte.
-;
-unmangle_name:	call strcpy
-		dec di				; Point to final null byte
-		ret
-
-	
-
-; -----------------------------------------------------------------------------
-;  Common modules
-; -----------------------------------------------------------------------------
-
-%include "common.inc"		; Universal modules
-%include "plaincon.inc"		; writechr
-%include "writestr.inc"		; String output
-%include "writehex.inc"		; Hexadecimal output
-%include "localboot.inc"	; Disk-based local boot
-
-; -----------------------------------------------------------------------------
-;  Begin data section
-; -----------------------------------------------------------------------------
-
-		section .data16
-copyright_str   db ' Copyright (C) 1994-'
-		asciidec YEAR
-		db ' H. Peter Anvin et al', CR, LF, 0
-err_bootfailed	db CR, LF, 'Boot failed: please change disks and press '
-		db 'a key to continue.', CR, LF, 0
-;
-; Config file keyword table
-;
-%include "keywords.inc"
-
-;
-; Extensions to search for (in *forward* order).
-;
-exten_table:	db '.cbt'		; COMBOOT (specific)
-		db '.bss'		; Boot Sector (add superblock)
-		db '.bs', 0		; Boot Sector
-		db '.com'		; COMBOOT (same as DOS)
-		db '.c32'		; COM32
-exten_table_end:
-		dd 0, 0			; Need 8 null bytes here
-
-;
-; Misc initialized (data) variables
-;
-%ifdef debug				; This code for debugging only
-debug_magic	dw 0D00Dh		; Debug code sentinel
-%endif
-
-		alignz 4
-BufSafe		dw trackbufsize/SECTOR_SIZE	; Clusters we can load into trackbuf
-BufSafeBytes	dw trackbufsize		; = how many bytes?
-%ifndef DEPEND
-%if ( trackbufsize % SECTOR_SIZE ) != 0
-%error trackbufsize must be a multiple of SECTOR_SIZE
-%endif
-%endif
+%include "diskfs.inc"