bootlace.inc

grub4dos-0.4.4-2008- 08-src.zip

/*
 *  bootlace.inc -- code shared by 16-bit DOS and 32-bit Linux
 *  Copyright (C) 2005,2006,2007  Tinybit([e-mail])
 *
 *  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; either version 2 of the License, or
 *  (at your option) any later version.
 *
 *  This program is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *  GNU General Public License for more details.
 *
 *  You should have received a copy of the GNU General Public License
 *  along with this program; if not, write to the Free Software
 *  Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 */

	.file	"bootlace.inc"

#ifdef __DOS_16

#undef ABS
#define ABS(x) (x - _start + 0x100)

#undef iBX
#define iBX	%bx

#undef iSI
#define iSI	%si

#undef iDI
#define iDI	%di

#undef iDX
#define iDX	%dx

#undef LEAL
#define LEAL	ADDR32 leal

#undef MOVZWL
#define MOVZWL	ADDR32 movzwl

#undef MOVL
#define MOVL	ADDR32 movl

#undef MOVW
#define MOVW	ADDR32 movw

#undef CMPL
#define CMPL	ADDR32 cmpl

#undef CMPW
#define CMPW	ADDR32 cmpw

#undef SUBL
#define SUBL	ADDR32 subl

#undef SBBL
#define SBBL	ADDR32 sbbl

#undef NEGL
#define NEGL	ADDR32 negl

#undef NOTL
#define NOTL	ADDR32 notl

#undef ADCL
#define ADCL	ADDR32 adcl

#undef ADDL
#define ADDL	ADDR32 addl

#undef DIVL
#define DIVL	ADDR32 divl

	. = _start + 0x34		// dos entry point invalid_dos_exec 

#if 0
	movl	$ABS(msg_invalid_dos), %ecx
	call	8f

	movw	$0x4c01, %ax		// EXIT - TERMINATE WITH RETURN CODE 1
	int	$0x21			// call DOS
#else
	jmp	1f
#endif


	//////////////////////////////////////////////////////////////////////
	
	. = _start + 0x47		// dos entry point

1:
	/* dos entry point */

	movl	$0x81, %esi
	movl	%esi, %edi
	movl	$0x7f, %ecx
	movb	$0x0d, %al	/* CR */

	cld
	repnz scasb

	decl	%edi		/* points to CR */
	std
	movb	$0, %al
	stosb
	movl	%edi, %esi
	xorl	%ecx, %ecx
	pushl	%ecx		/* 0 is the end of argv */
	xorl	%edx, %edx	/* find spaces */
3:
	cmpl	$0x81, %edi
	jb	3f
	lodsb
	cmpb	$0x20, %al
	je	1f
	cmpb	$0x09, %al
	jne	2f
1:
	testl	%edx, %edx
	jz	1f
	notl	%edx
	incl	%edi
	pushl	%edi		/* argv */
	decl	%edi
1:
	movb	$0, %al
	stosb
	jmp	3b
2:
	testl	%edx, %edx
	jnz	1f
	incl	%ecx
	notl	%edx
1:
	stosb
	jmp	3b
3:
	testl	%edx, %edx
	jz	1f
	incl	%edi
	pushl	%edi
1:
	pushl	%esi		/* dummy for program name */
	incl	%ecx
	pushl	%ecx		/* argc */
	cld
#else

#undef ABS
#define ABS(x) (x)

#undef iBX
#define iBX	%ebx

#undef iSI
#define iSI	%esi

#undef iDI
#define iDI	%edi

#undef iDX
#define iDX	%edx

#undef LEAL
#define LEAL	leal

#undef MOVZWL
#define MOVZWL	movzwl

#undef MOVL
#define MOVL	movl

#undef MOVW
#define MOVW	movw

#undef CMPL
#define CMPL	cmpl

#undef CMPW
#define CMPW	cmpw

#undef SUBL
#define SUBL	subl

#undef SBBL
#define SBBL	sbbl

#undef NEGL
#define NEGL	negl

#undef NOTL
#define NOTL	notl

#undef ADCL
#define ADCL	adcl

#undef ADDL
#define ADDL	addl

#undef DIVL
#define DIVL	divl

#endif

	popl	%ecx		# argc

	/* argc must be > 1 */

	xorl	%ebx, %ebx	# invalid file descriptor for CLOSE below
	
	cmpl	$1, %ecx
	movl	$ABS(msg_no_args), %ecx
	jbe	4f	/* error */

	/* Note: ECX does not hold the argc now. */

	xorl	%eax, %eax		# EAX will point to file name
	//movl	%ebx, ABS(filename)	# save 0 to filename
	popl	%ecx		# discard argv[0], the program name
1:
	popl	%ecx		# argv
	movl	%ecx, %ebx
	test 	%ecx, %ecx
	jz	1f		# end of arguments

	/* check if it is an option */
	cmpb	$0x2D, (iBX)	# "-"
	jz	2f

	/* it is a filename */

	testl	%eax, %eax	# filename already specified?
	//cmpl	$0, ABS(filename)
	jz	3f

	/* error: only one file should be specified. */

	xorl	%ebx, %ebx	# invalid file descriptor for CLOSE below
	
	movl	$ABS(msg_too_many_files), %ecx
	jmp	4f	/* error */

3:

	/* not yet, this is the first filename */

	movl	%ecx, %eax		# save ECX to EAX
	//movl	%ecx, ABS(filename)	# save ECX to filename
	jmp	1b			# continue

2:

	/* it is an option */

	/* check --no-backup-mbr */

	movl	$16, %ecx
	movl	$ABS(option_no_backup_mbr), %esi
	movl	%ebx, %edi

	cld
	repz cmpsb

	jnz	3f

	xorl	%ebx, %ebx	# invalid file descriptor for CLOSE below
	
	cmpl	$1, ABS(backup_mbr)
	movl	$ABS(msg_option_backup_mbr), %ecx
	jnz	4f	/* error */
	movl	$0, ABS(backup_mbr)
	jmp	1b

3:
	/* check --force-backup-mbr */

	movl	$19, %ecx
	movl	$ABS(option_force_backup_mbr), %esi
	movl	%ebx, %edi

	cld
	repz cmpsb

	jnz	3f

	xorl	%ebx, %ebx	# invalid file descriptor for CLOSE below
	
	cmpl	$1, ABS(backup_mbr)
	movl	$ABS(msg_option_backup_mbr), %ecx
	jnz	4f	/* error */
	movl	$2, ABS(backup_mbr)
	jmp	1b

3:

	/* check --mbr-enable-floppy */

	movl	$20, %ecx
	movl	$ABS(option_mbr_enable_floppy), %esi
	movl	%ebx, %edi

	cld
	repz cmpsb

	jnz	3f

	xorl	%ebx, %ebx	# invalid file descriptor for CLOSE below
	
	cmpl	$0, ABS(mbr_floppy)
	movl	$ABS(msg_option_mbr_floppy), %ecx
	jnz	4f	/* error */
	movl	$2, ABS(mbr_floppy)
	jmp	1b

3:

	/* check --mbr-disable-floppy */

	movl	$21, %ecx
	movl	$ABS(option_mbr_disable_floppy), %esi
	movl	%ebx, %edi

	cld
	repz cmpsb

	jnz	3f

	xorl	%ebx, %ebx	# invalid file descriptor for CLOSE below
	
	cmpl	$0, ABS(mbr_floppy)
	movl	$ABS(msg_option_mbr_floppy), %ecx
	jnz	4f	/* error */
	movl	$1, ABS(mbr_floppy)
	jmp	1b

3:

	/* check --mbr-enable-osbr */

	movl	$18, %ecx
	movl	$ABS(option_mbr_enable_osbr), %esi
	movl	%ebx, %edi

	cld
	repz cmpsb

	jnz	3f

	xorl	%ebx, %ebx	# invalid file descriptor for CLOSE below
	
	cmpl	$0, ABS(mbr_osbr)
	movl	$ABS(msg_option_mbr_osbr), %ecx
	jnz	4f	/* error */
	movl	$2, ABS(mbr_osbr)
	jmp	1b

3:

	/* check --mbr-disable-osbr */

	movl	$19, %ecx
	movl	$ABS(option_mbr_disable_osbr), %esi
	movl	%ebx, %edi

	cld
	repz cmpsb

	jnz	3f

	xorl	%ebx, %ebx	# invalid file descriptor for CLOSE below
	
	cmpl	$0, ABS(mbr_osbr)
	movl	$ABS(msg_option_mbr_osbr), %ecx
	jnz	4f	/* error */
	movl	$1, ABS(mbr_osbr)
	jmp	1b

3:

	/* check --duce */

	movl	$7, %ecx
	movl	$ABS(option_duce), %esi
	movl	%ebx, %edi

	cld
	repz cmpsb

	jnz	3f

	xorl	%ebx, %ebx	# invalid file descriptor for CLOSE below
	
	cmpl	$0, ABS(duce)
	movl	$ABS(msg_option_duce), %ecx
	jnz	4f	/* error */
	movl	$1, ABS(duce)
	jmp	1b

3:

	/* check --boot-prevmbr-first */

	movl	$21, %ecx
	movl	$ABS(option_boot_prevmbr_first), %esi
	movl	%ebx, %edi

	cld
	repz cmpsb

	jnz	3f

	xorl	%ebx, %ebx	# invalid file descriptor for CLOSE below
	
	cmpl	$0, ABS(boot_prevmbr)
	movl	$ABS(msg_option_boot_prevmbr), %ecx
	jnz	4f	/* error */
	movl	$1, ABS(boot_prevmbr)
	jmp	1b

3:

	/* check --boot-prevmbr-last */

	movl	$20, %ecx
	movl	$ABS(option_boot_prevmbr_last), %esi
	movl	%ebx, %edi

	cld
	repz cmpsb

	jnz	3f

	xorl	%ebx, %ebx	# invalid file descriptor for CLOSE below
	
	cmpl	$0, ABS(boot_prevmbr)
	movl	$ABS(msg_option_boot_prevmbr), %ecx
	jnz	4f	/* error */
	movl	$2, ABS(boot_prevmbr)
	jmp	1b

3:

	/* check --preferred-drive= */

	movl	$18, %ecx
	movl	$ABS(option_preferred_drive), %esi
	movl	%ebx, %edi

	cld
	repz cmpsb

	jnz	3f

	xorl	%ebx, %ebx	# invalid file descriptor for CLOSE below
	
	cmpl	$0xff, ABS(preferred_drive)
	movl	$ABS(msg_option_preferred_drive), %ecx
	jnz	4f	/* error */

	movl	$0xfe, %ebx
	call	7f	/* parse_number */
	movl	%ebx, %edi	# save EBX to EDI
	movl	$0, %ebx	# invalid file descriptor for CLOSE below
	movl	$ABS(msg_invalid_number), %ecx
	jc	4f	/* error */
	movl	%edi, ABS(preferred_drive)
	jmp	1b

3:

	/* check --preferred-partition= */

	movl	$22, %ecx
	movl	$ABS(option_preferred_partition), %esi
	movl	%ebx, %edi

	cld
	repz cmpsb

	jnz	3f

	xorl	%ebx, %ebx	# invalid file descriptor for CLOSE below
	
	cmpl	$0xff, ABS(preferred_partition)
	movl	$ABS(msg_option_preferred_partition), %ecx
	jnz	4f	/* error */

	movl	$0xfe, %ebx
	call	7f	/* parse_number */
	movl	%ebx, %edi	# save EBX to EDI
	movl	$0, %ebx	# invalid file descriptor for CLOSE below
	movl	$ABS(msg_invalid_number), %ecx
	jc	4f	/* error */
	movl	%edi, ABS(preferred_partition)
	jmp	1b

3:

	/* check --time-out= */

	movl	$11, %ecx
	movl	$ABS(option_time_out), %esi
	movl	%ebx, %edi

	cld
	repz cmpsb

	jnz	3f

	xorl	%ebx, %ebx	# invalid file descriptor for CLOSE below
	
	cmpl	$0xffffff05, ABS(time_out)
	movl	$ABS(msg_option_time_out), %ecx
	jnz	4f	/* error */

	movl	$0xff, %ebx
	call	7f	/* parse_number */
	movl	%ebx, %edi	# save EBX to EDI
	movl	$0, %ebx	# invalid file descriptor for CLOSE below
	movl	$ABS(msg_invalid_number), %ecx
	jc	4f	/* error */
	movl	%edi, ABS(time_out)
	jmp	1b

3:

	/* check --hot-key= */

	movl	$10, %ecx
	movl	$ABS(option_hot_key), %esi
	movl	%ebx, %edi

	cld
	repz cmpsb

	jnz	3f

	xorl	%ebx, %ebx	# invalid file descriptor for CLOSE below
	
	cmpl	$0xffff3920, ABS(hot_key)
	movl	$ABS(msg_option_hot_key), %ecx
	jnz	4f	/* error */

	movl	$0xffff, %ebx
	call	7f	/* parse_number */
	movl	%ebx, %edi	# save EBX to EDI
	movl	$0, %ebx	# invalid file descriptor for CLOSE below
	movl	$ABS(msg_invalid_number), %ecx
	jc	4f	/* error */
	movl	%edi, ABS(hot_key)
	jmp	1b

3:

	/* check --install-partition= */

	movl	$20, %ecx
	movl	$ABS(option_install_partition), %esi
	movl	%ebx, %edi

	cld
	repz cmpsb

	jnz	3f

	xorl	%ebx, %ebx	# invalid file descriptor for CLOSE below
	
	cmpl	$0xffffffff, ABS(install_partition)
	movl	$ABS(msg_option_install_partition), %ecx
	jnz	4f	/* error */

	movl	$0xffff, %ebx
	call	7f	/* parse_number */
	movl	%ebx, %edi	# save EBX to EDI
	movl	$0, %ebx	# invalid file descriptor for CLOSE below
	movl	$ABS(msg_invalid_number), %ecx
	jc	4f	/* error */
	movl	%edi, ABS(install_partition)
	jmp	1b

3:

	/* check --sectors-per-track= */

	movl	$20, %ecx
	movl	$ABS(option_sectors_per_track), %esi
	movl	%ebx, %edi

	cld
	repz cmpsb

	jnz	3f

	xorl	%ebx, %ebx	# invalid file descriptor for CLOSE below
	
	cmpl	$0xffffff3f, ABS(sectors_per_track)
	movl	$ABS(msg_option_sectors_per_track), %ecx
	jnz	4f	/* error */

	movl	$0x3f, %ebx	# maximum is 63
	call	7f	/* parse_number */
	movl	%ebx, %edi	# save EBX to EDI
	movl	$0, %ebx	# invalid file descriptor for CLOSE below
	movl	$ABS(msg_invalid_number), %ecx
	jc	4f	/* error */
	cmpl	$0, %edi
	je	4f	/* error */
	movl	%edi, ABS(sectors_per_track)
	jmp	1b

3:

	/* check --heads= */

	movl	$8, %ecx
	movl	$ABS(option_heads), %esi
	movl	%ebx, %edi

	cld
	repz cmpsb

	jnz	3f

	xorl	%ebx, %ebx	# invalid file descriptor for CLOSE below
	
	cmpl	$0xffff00ff, ABS(heads)
	movl	$ABS(msg_option_heads), %ecx
	jnz	4f	/* error */

	movl	$0x100, %ebx	# maximum is 256
	call	7f	/* parse_number */
	movl	%ebx, %edi	# save EBX to EDI
	movl	$0, %ebx	# invalid file descriptor for CLOSE below
	movl	$ABS(msg_invalid_number), %ecx
	jc	4f	/* error */
	cmpl	$0, %edi
	je	4f	/* error */
	movl	%edi, ABS(heads)
	jmp	1b

3:

	/* check --start-sector= */

	movl	$15, %ecx
	movl	$ABS(option_start_sector), %esi
	movl	%ebx, %edi

	cld
	repz cmpsb

	jnz	3f

	xorl	%ebx, %ebx	# invalid file descriptor for CLOSE below
	
	cmpl	$0xffffffff, ABS(start_sector)
	movl	$ABS(msg_option_start_sector), %ecx
	jnz	4f	/* error */

	movl	$0xfffffffe, %ebx
	call	7f	/* parse_number */
	movl	%ebx, %edi	# save EBX to EDI
	movl	$0, %ebx	# invalid file descriptor for CLOSE below
	movl	$ABS(msg_invalid_number), %ecx
	jc	4f	/* error */
	movl	%edi, ABS(start_sector)
	jmp	1b

3:

	/* check --total-sectors= */

	movl	$16, %ecx
	movl	$ABS(option_total_sectors), %esi
	movl	%ebx, %edi

	cld
	repz cmpsb