Merge pull request #121 from Konamiman/support-extended-partition-lba

docs/Nextor 2.1 Programmers Reference.md

@@ -501,11 +501,14 @@ The partition type code returns information about the filesystem that the partit
 0: None (the partition with the specified number does not exist)
 1: FAT12
 4: FAT16, smaller than 32MB (obsolete)
-5: Extended (see below)
+5: Extended (CHS) (see below)
 6: FAT16 (CHS)
 14: FAT16 (LBA)
+15: Extended (LBA)
 ```
 
+**Note:** Prior to version 2.1.2, Nextor would only recognize a partition as extended if it had the partition type code 5 (extended CHS), and FDISK would use this code when creating extended partitions. Starting with Nextor 2.1.2, FDISK will use partition type code 15 (extended LBA) when creating extended partitions, and both 5 and 15 will be recognized as valid extended partition type codes when scanning existing partitions with `_GPART`. In the description below, "Extended" means "Either extended CHS or extended LBA".
+
 There are many more partition type codes defined, but they refer to filesystems that can't be handled by Nextor so they are not listed here.
 
 A device can have up to four primary partitions, numbered 1 to 4. In order to accommodate more than four partitions, partition number 2 may be of a special type named "Extended". An extended partition is actually a container for more partitions; there is no limit in the number of extra partitions that a partition of type "Extended" can contain. Primary partitions 3 and 4 do not exist when partition 2 is extended.

source/kernel/bank2/val.mac

@@ -8,20 +8,8 @@
 	INCLUDE	../const.inc
 	RAMMOD
 
-MBR_PSTART	equ	01BEh	;Start of partition table in MBR
-MBR_PSIZE	equ	16	;Size of partition table entry
-POFF_TYPE	equ	4	;Offset of partition type in p. table entry
-POFF_PSTART	equ	8	;Offset of partition start in p. table entry
-POFF_PSIZE	equ	12	;Offset of partition size in p. table entry
-PT_FAT12	equ	1	;Partition type code for FAT12
-PT_FAT16_S	equ	4	;Partition type code for FAT16 (< 32M)
-PT_EXT		equ	5	;Partition type code for extended partition
-PT_FAT16	equ	6	;Partition type code for FAT16
-PT_FAT16_L	equ 14  ;Partition type code for FAT16 (LBA)
-MBR_SIG		equ	512-2	;MBR signature offset in MBR (55h, AAh)
 MAXCLUS_FAT12	equ	4084
 MAXCLUS_12BITS	equ	4095
-
 ;
 ;-----------------------------------------------------------------------------
 ;

source/kernel/bank4/partit.mac

@@ -23,7 +23,8 @@ POFF_PSTART	equ	8	;Offset of partition start in p. table entry
 POFF_PSIZE	equ	12	;Offset of partition size in p. table entry
 PT_FAT12	equ	1	;Partition type code for FAT12
 PT_FAT16_S	equ	4	;Partition type code for FAT16 (< 32M)
-PT_EXT		equ	5	;Partition type code for extended partition
+PT_EXT		equ	5	;Partition type code for extended partition (CHS)
+PT_EXT_LBA  equ 15  ;Partition type code for extended partition (LBA)
 PT_FAT16	equ	6	;Partition type code for FAT16
 PT_FAT16_L	equ 14  ;Partition type code for FAT16 (LBA)
 
@@ -205,7 +206,7 @@ DO_EXTPAR:
 	;--- If extended partition requested, first check that partition is actually extended
 
 	ld	a,(ix+POFF_TYPE)
-	cp	PT_EXT
+	call IS_EXT_PART
 	jp	nz,UNEX_PART
 
 	ld	a,(ix+POFF_PSTART)	;Save the start sector number of the outer extended partition
@@ -285,7 +286,7 @@ EXTP_NEXT:
 	pop	bc
 
 	ld	a,(ix+POFF_TYPE)
-	cp	PT_EXT
+	call IS_EXT_PART
 	jr	nz,TPIY_UNEX_PART
 
 	jr	EXTP_LOOP
@@ -1232,7 +1233,7 @@ AA_PX_DOEMU:
 
 AA_PX_NOEMU:
     ld	a,b	;Partition type
-    cp  PT_EXT
+    call IS_EXT_PART
     jr  nz,AA_PX_NOEX
     ld a,(ix+AAD_CURR_PART_INDEX)
     or 80h
@@ -4505,7 +4506,7 @@ MAPDRV_NOP0:
 	ld	c,_GPART##
 	call	BASIC_DOS
 	ld	a,b
-	cp	5	;Extended partition?
+	call IS_EXT_PART	;Extended partition?
 
 	pop	bc
 	ld	a,b
@@ -4540,7 +4541,7 @@ MAPDRV_GOTPAR:
 	ld	a,b
 	or	a
 	jp	z,BASIC_ERR
-	cp	5
+	call IS_EXT_PART
 	jp	z,BASIC_ERR	;"Invalid partition" error if non existing or extended partition
 	ld	e,c
 
@@ -6278,5 +6279,16 @@ STRCOMP:
 	inc	de
 	jr	STRCOMP
 
+
+; Check if the partition type passed in A
+; corresponds to a recognized extended partition type,
+; return Z if so or NZ otherwise
+
+IS_EXT_PART:
+	cp PT_EXT
+	ret z
+	cp PT_EXT_LBA
+	ret
+
 	finish <PARTIT>
 	end

source/kernel/bank5/fdisk.c

@@ -841,7 +841,7 @@ byte GetDiskPartitionsInfo()
 		DosCallFromRom(_GPART, REGS_ALL);
 		error = regs.Bytes.A;
 		if(error == 0) {
-			if(regs.Bytes.B == PARTYPE_EXTENDED) {
+			if(regs.Bytes.B == PARTYPE_EXTENDED || regs.Bytes.B == PARTYPE_EXTENDED_LBA) {
 				extendedIndex = 1;
 			} else {
 				currentPartition->primaryIndex = primaryIndex;

source/kernel/bank5/fdisk2.c

@@ -415,7 +415,7 @@ int CalculateFatFileSystemParametersFat16(ulong fileSystemSizeInK, dosFilesystem
 	clusterCount = dataSectorsCount >> sectorsPerClusterPower;
 	sectorsPerFat = (clusterCount + 2) >> 8;
 
-	if(((clusterCount + 2) & 0x3FF) != 0) {
+	if(((clusterCount + 2) & 0xFF) != 0) {
 		sectorsPerFat++;
 	}
 
@@ -515,7 +515,7 @@ int CreatePartition(int index)
 
 	if(index != (partitionsCount - 1)) {
 		tableEntry++;
-		tableEntry->partitionType = PARTYPE_EXTENDED;
+		tableEntry->partitionType = PARTYPE_EXTENDED_LBA;
 		tableEntry->firstAbsoluteSector = nextDeviceSector;
 		if(index == 0) {
 			mainExtendedPartitionFirstSector = nextDeviceSector;

source/tools/C/Makefile

@@ -11,7 +11,7 @@ define copy_to_bin
 	cp $(1) ../../../bin/tools/$(2)
 endef
 
-COMS := emufile.com fsize.com nexboot.com vsft.com
+COMS := emufile.com fsize.com nexboot.com vsft.com eptcft.com
 
 c-tools: $(COMS)