cd boot workaround for bioses that didn't want to boot >4 image sectors.

boot is a normal binary with a.out again. use 'cdbootblock,' a CDBOOT
variant of bootblock, both from bootblock.s, as the first boot image
that then loads boot, exactly like the bootblock loads boot when booting
from harddisk. the sector numbers (2048 byte iso sectors) are patched in
by writeisofs, like installboot does for bootblock. bootblock unchanged.

boot/Makefile

@@ -11,12 +11,15 @@ LD86	= $(CC86) -.o
 BIN	= /usr/bin
 MDEC	= /usr/mdec
 
-all:	bootblock boot edparams masterboot jumpboot installboot addaout
+all:	bootblock cdbootblock boot edparams masterboot jumpboot installboot addaout
 dos:	boot.com mkfile.com
 
 bootblock:	bootblock.s
 	$(LD86) -com -o $@ bootblock.s
 
+cdbootblock:	bootblock.s
+	$(LD86) -com -o $@ bootblock.s -DCDBOOT
+
 masterboot:	masterboot.s
 	$(LD86) -com -o $@ masterboot.s
 
@@ -36,16 +39,8 @@ rawfs86.o:	rawfs.c rawfs.o
 	-cmp -s rawfs.o rawfs86.o && ln -f rawfs.o rawfs86.o
 
 boot:	boothead.s boot.o bootimage.o rawfs86.o
-	$(LD86) -o bootexec \
+	$(LD86) -o boot boothead.s boot.o bootimage.o rawfs86.o $(LIBS)
-		boothead.s boot.o bootimage.o rawfs86.o $(LIBS)
+	install -S 22kb boot
-	install -S 22kb bootexec
-	# This is code that is executed when used on a bootable
-	# CD, as its entry point is the start of the file then.
-	# It jumps over the a.out header into the part of the
-	# code in boothead.s where the code knows it's booting
-	# from CD if entered there.
-	( printf '\xeb\x3e              ' ; cat bootexec ) >boot
-	chmod 755 boot
 
 edparams.o:	boot.c
 	ln -f boot.c edparams.c
@@ -119,5 +114,5 @@ $(BIN)/edparams:	edparams
 
 clean:
 	rm -f *.bak *.o
-	rm -f bootblock addaout installboot boot masterboot jumpboot edparams
+	rm -f cdbootblock bootblock addaout installboot boot masterboot jumpboot edparams
 	rm -f dosboot boot.com mkfile mkfile.com

boot/bootblock.s

@@ -1,3 +1,4 @@
+#
 !	Bootblock 1.5 - Minix boot block.		Author: Kees J. Bot
 !					   			21 Dec 1991
 !
@@ -18,15 +19,21 @@
 
 	LOADOFF	   =	0x7C00	! 0x0000:LOADOFF is where this code is loaded
 	BOOTSEG    =	0x1000	! Secondary boot code segment.
+#ifdef CDBOOT
+	BOOTOFF	   =	0x0050	! Offset into /boot above header
+#else
 	BOOTOFF	   =	0x0030	! Offset into /boot above header
+#endif
 	BUFFER	   =	0x0600	! First free memory
+#ifndef CDBOOT			/* just constants, but make no sense for CDs */
 	LOWSEC     =	     8	! Offset of logical first sector in partition
 				! table
 
 	! Variables addressed using bp register
-	device	   =	     0	! The boot device
 	lowsec	   =	     2	! Offset of boot partition within drive
 	secpcyl	   =	     6	! Sectors per cylinder = heads * sectors
+#endif
+	device	   =	     0	! The boot device
 
 .text
 
@@ -51,18 +58,21 @@ boot:
 
 	mov	di, #LOADOFF+sectors	! char *di = sectors;
 
+#ifndef CDBOOT
 	testb	dl, dl		! Winchester disks if dl >= 0x80
 	jge	floppy
+#endif
 
 winchester:
 
+#ifndef CDBOOT
 ! Get the offset of the first sector of the boot partition from the partition
 ! table.  The table is found at es:si, the lowsec parameter at offset LOWSEC.
 
 	eseg
 	les	ax, LOWSEC(si)	  ! es:ax = LOWSEC+2(si):LOWSEC(si)
-	mov	lowsec+0(bp), ax  ! Low 16 bits of partition's first sector
+	mov	lowsec+0(bp), ax  ! Low 16 bits of partitions first sector
-	mov	lowsec+2(bp), es  ! High 16 bits of partition's first sector
+	mov	lowsec+2(bp), es  ! High 16 bits of partitions first sector
 
 ! Get the drive parameters, the number of sectors is bluntly written into the
 ! floppy disk sectors/track array.
@@ -72,8 +82,10 @@ winchester:
 	andb	cl, #0x3F	! cl = max sector number (1-origin)
 	movb	(di), cl	! Number of sectors per track
 	incb	dh		! dh = 1 + max head number (0-origin)
+#endif
 	jmp	loadboot
 
+#ifndef CDBOOT
 ! Floppy:
 ! Execute three read tests to determine the drive type.  Test for each floppy
 ! type by reading the last sector on the first track.  If it fails, try a type
@@ -101,13 +113,16 @@ floppy:	xorb	ah, ah		! Reset drive
 	jc	next		! Error, try the next floppy type
 
 success:movb	dh, #2		! Load number of heads for multiply
+#endif
 
 loadboot:
 ! Load /boot from the boot device
 
+#ifndef CDBOOT
 	movb	al, (di)	! al = (di) = sectors per track
 	mulb	dh		! dh = heads, ax = heads * sectors
 	mov	secpcyl(bp), ax	! Sectors per cylinder = heads * sectors
+#endif
 
 	mov	ax, #BOOTSEG	! Segment to load /boot into
 	mov	es, ax
@@ -117,6 +132,7 @@ load:
 	mov	ax, 1(si)	! Get next sector number: low 16 bits
 	movb	dl, 3(si)	! Bits 16-23 for your up to 8GB partition
 	xorb	dh, dh		! dx:ax = sector within partition
+#ifndef CDBOOT
 	add	ax, lowsec+0(bp)
 	adc	dx, lowsec+2(bp)! dx:ax = sector within drive
 	cmp	dx, #[1024*255*63-255]>>16  ! Near 8G limit?
@@ -136,13 +152,14 @@ load:
 	movb	al, (di)	! Sectors per track - Sector number (0-origin)
 	subb	al, ah		! = Sectors left on this track
 	cmpb	al, (si)	! Compare with # sectors to read
-	jbe	read		! Can't read past the end of a cylinder?
+	jbe	read		! Cant read past the end of a cylinder?
 	movb	al, (si)	! (si) < sectors left on this track
 read:	push	ax		! Save al = sectors to read
 	movb	ah, #0x02	! Code for disk read (all registers in use now!)
 	int	0x13		! Call the BIOS for a read
 	pop	cx		! Restore al in cl
 	jmp	rdeval
+#endif
 bigdisk:
 	movb	cl, (si)	! Number of sectors to read
 	push	si		! Save si
@@ -161,6 +178,14 @@ rdeval:
 	movb	al, cl		! Restore al = sectors read
 	addb	bh, al		! bx += 2 * al * 256 (add bytes read)
 	addb	bh, al		! es:bx = where next sector must be read
+#ifdef CDBOOT
+	addb	bh, al		! For CDs, a sector is 2048 bytes, so
+	addb	bh, al		! do this 6 more times to get byte count.
+	addb	bh, al		
+	addb	bh, al		
+	addb	bh, al		
+	addb	bh, al		
+#endif
 	add	1(si), ax	! Update address by sectors read
 	adcb	3(si), ah	! Don't forget bits 16-23 (add ah = 0)
 	subb	(si), al	! Decrement sector count by sectors read

boot/boothead.s

@@ -46,25 +46,29 @@
 
 .text
 
-! We assume boot is always linked with a short (32 byte) a.out header and has
-! 16 bytes of its own prefix, so 48 bytes to skip. bootblock jumps into us
-! at offset 0x30, cd boot code at 0x40
 
-	! Set cs right
+! Set segment registers and stack pointer using the programs own header!
-	! (skip short a.out header plus 16 byte preefix)
+! The header is either 32 bytes (short form) or 48 bytes (long form).  The
-	jmpf	boot, LOADSEG+3		
+! bootblock will jump to address 0x10030 in both cases, calling one of the
-	.space	11
+! two jmpf instructions below.
+!
+! CD bootblock jumps to address 0x10050 in both cases.
 
-	! entry point when booting from CD
+	jmpf	boot, LOADSEG+3	! Set cs right (skipping long a.out header)
+	.space	11		! jmpf + 11 = 16 bytes
+	jmpf	boot, LOADSEG+2	! Set cs right (skipping short a.out header)
+	.space	11		! jmpf + 11 = 16 bytes
 	jmpf	cdboot, LOADSEG+3
 	.space	11		
+	jmpf	cdboot, LOADSEG+2
+	.space	11		
 cdboot:
 	mov	bx, #1
 	jmp	commonboot
 boot:
 	mov	bx, #0
 commonboot:
-	mov	ax, #LOADSEG+1
+	mov	ax, #LOADSEG
 	mov	ds, ax		! ds = header
 
 	movb	al, a_flags
@@ -129,7 +133,7 @@ sepID:
 	mov	_daddr+0, ax
 	mov	_daddr+2, dx
 	push	ds
-	mov	ax, #LOADSEG+1
+	mov	ax, #LOADSEG
 	mov	ds, ax		! Back to the header once more
 	mov	ax, a_total+0
 	mov	dx, a_total+2	! dx:ax = data + bss + heap + stack

boot/installboot.c

@@ -495,8 +495,7 @@ void make_bootable(enum howto how, char *device, char *bootblock,
 			boothdr.a_magic[0]= !A_MAGIC0;
 		} else {
 			readblock(addr, buf, block_size);
-			/* Must skip 16 bytes of 'boot' as that contains code. */
+			memcpy(&boothdr, buf, sizeof(struct exec));
-			memcpy(&boothdr, buf + 16, sizeof(struct exec));
 		}
 		bootf= NULL;
 		dummy.process= boothdr;

commands/simple/writeisofs.c

@@ -9,7 +9,9 @@
 #include <string.h>
 #include <unistd.h>
 #include <dirent.h>
+#include <assert.h>
 #include <ctype.h>
+#include <a.out.h>
 #include <machine/partition.h>
 
 #include <sys/stat.h>
@@ -38,6 +40,7 @@ typedef unsigned long int u_int32_t;
 
 #define ISO_SECTOR 2048
 #define VIRTUAL_SECTOR	512
+#define ROUNDUP(v, n) (((v)+(n)-1)/(n))
 
 #define CURRENTDIR	"."
 #define PARENTDIR	".."
@@ -755,7 +758,7 @@ writebootcatalog(int fd, int  *currentsector, int imagesector, int imagesectors)
 
 	/* fill out the rest of the sector with 0's */
 
-	if((rest = ISO_SECTOR - (written % 2048))) {
+	if((rest = ISO_SECTOR - (written % ISO_SECTOR))) {
 		memset(buf, 0, sizeof(buf));
 		written += Write(fd, buf, rest);
 	}
@@ -766,23 +769,80 @@ writebootcatalog(int fd, int  *currentsector, int imagesector, int imagesectors)
 }
 
 int
-writebootimage(char *bootimage, int bootfd, int fd, int *currentsector)
+writebootimage(char *bootimage, int bootfd, int fd, int *currentsector,
+	char *appendsectorinfo, struct node *root)
 {
-	static char buf[1024*64];
+	static unsigned char buf[1024*64], *addr;
-	ssize_t chunk, written = 0, rest;
+	ssize_t written = 0, rest;
-	int virtuals;
+	int virtuals, rem;
+	struct exec hdr;
+	struct bap {
+		off_t sector;
+		int length;
+	} bap[2];
 
-	while((chunk=read(bootfd, buf, sizeof(buf))) > 0)
+	bap[1].length = bap[1].sector = 0;
-		written += Write(fd, buf, chunk);
 
-	if(chunk < 0) {
+	Read(bootfd, &hdr, A_MINHDR);
-		perror("read boot image");
+
+	if(hdr.a_magic[0] != A_MAGIC0) {
+		fprintf(stderr, "bad magic in a.out of boot image.\n");
 		exit(1);
 	}
 
-	virtuals = written / VIRTUAL_SECTOR;
+	if(hdr.a_hdrlen > sizeof(hdr)) {
+		fprintf(stderr, "surprisingly large header in boot image.\n");
+		exit(1);
+	}
 
-	if((rest = ISO_SECTOR - (written % 2048))) {
+	/* read rest of a.out header. */
+	Read(bootfd, (char *) &hdr + A_MINHDR, hdr.a_hdrlen - A_MINHDR);
+
+	/* copy text+data */
+	rem = hdr.a_text + hdr.a_data;
+
+	while(rem > 0) {
+		int want;
+		want = rem < sizeof(buf) ? rem : sizeof(buf);
+		Read(bootfd, buf, want);
+		written += Write(fd, buf, want);
+		rem -= want;
+	}
+
+	if(appendsectorinfo) {
+		struct node *n;
+		for(n = root->firstchild; n; n = n ->nextchild) {
+			if(!strcasecmp(appendsectorinfo, n->name)) {
+				bap[0].sector = n->startsector;
+				bap[0].length = ROUNDUP(n->bytesize, ISO_SECTOR);
+				break;
+			}
+		}
+		if(!n) {
+			fprintf(stderr, "%s not found in root.\n",
+				appendsectorinfo);
+			exit(1);
+		}
+
+		fprintf(stderr, " * appended sector info: 0x%lx len 0x%lx\n",
+			bap[0].sector, bap[0].length);
+	}
+
+	addr = buf;
+	addr[0] = bap[0].length;	assert(addr[0] > 0);
+	addr[1] = (bap[0].sector >>  0) & 0xFF;
+	addr[2] = (bap[0].sector >>  8) & 0xFF;
+	addr[3] = (bap[0].sector >> 16) & 0xFF;
+	addr[4] = 0;
+	addr[5] = 0;
+
+	/* Always save space for sector info after the boot image. */
+	written += Write(fd, addr, 6);
+
+        virtuals = ROUNDUP(written, VIRTUAL_SECTOR);
+        assert(virtuals * VIRTUAL_SECTOR >= written);                           
+
+	if((rest = ISO_SECTOR - (written % ISO_SECTOR))) {
 		memset(buf, 0, sizeof(buf));
 		written += Write(fd, buf, rest);
 	}
@@ -847,6 +907,7 @@ main(int argc, char *argv[])
 	int pvdsector;
 	int bigpath, littlepath, pathbytes = 0, dirsector, filesector, enddir;
 	int bootvolumesector, bootcatalogsector;
+	char *appendsectorinfo = NULL;
 
 	prog = argv[0];
 
@@ -861,7 +922,7 @@ main(int argc, char *argv[])
 		return 1;
 	}
 
-	while ((ch = getopt(argc, argv, "b:s:Rb:hl:nf")) != -1) {
+	while ((ch = getopt(argc, argv, "a:b:s:Rb:hl:nf")) != -1) {
 		switch(ch) {
 			case 's':
 				if(optarg[0] != '0' || optarg[1] != 'x') {
@@ -880,6 +941,10 @@ main(int argc, char *argv[])
 			case 'f':
 				bootmedia= BOOTMEDIA_144M;
 				break;
+			case 'a':
+				if(!(appendsectorinfo = strdup(optarg)))
+					exit(1);
+				break;
 			case 'l':
 				label = optarg;
 				break;
@@ -902,7 +967,7 @@ main(int argc, char *argv[])
 	/* Args check */
 
 	if(argc != 2) {
-		fprintf(stderr, "usage: %s [-l <label>] [-b <bootimage> [-n] [-f] [-h] [-s <bootsegment>] ] <dir> <isofile>\n",
+		fprintf(stderr, "usage: %s [-l <label>] [-b <bootimage> [-n] [-f] [-h] [-s <bootsegment>] [ -a <appendfile> ] <dir> <isofile>\n",
 			prog);
 		return 1;
 	}
@@ -920,6 +985,14 @@ main(int argc, char *argv[])
 		return 1;
 	}
 
+	if(appendsectorinfo) {
+		if(!bootimage || bootmedia != BOOTMEDIA_NONE) {
+			fprintf(stderr, "%s: append sector info where?\n",
+				prog);
+			return 1;
+		}
+	}
+
 	/* create .iso file */
 
 	if((fd=open(argv[1], O_WRONLY | O_TRUNC | O_CREAT, 0600)) < 0) {
@@ -1012,11 +1085,9 @@ main(int argc, char *argv[])
 		fprintf(stderr, " * writing the boot image\n");
 		imagesector = currentsector;
 		imagesectors = writebootimage(bootimage, bootfd,
-			fd, &currentsector);
+			fd, &currentsector, NULL, &root);
-		fprintf(stderr, " * image: %d virtual sectors @ sector 0x%x\n",
+		fprintf(stderr, " * image: %d %d-byte sectors @ cd sector 0x%x\n",
-			imagesectors, imagesector);
+			imagesectors, VIRTUAL_SECTOR, imagesector);
-
-		close(bootfd);
 	}
 
 	/* write out all the file data */
@@ -1088,6 +1159,16 @@ main(int argc, char *argv[])
 		fprintf(stderr, " * rewriting the boot rvd\n");
 		seeksector(fd, bootvolumesector, &currentsector);
 		writebootrecord(fd, &currentsector, bootcatalogsector);
+
+		if(appendsectorinfo) {
+			Lseek(bootfd, 0, SEEK_SET);
+			fprintf(stderr, " * rewriting boot image\n");
+			seeksector(fd, imagesector, &currentsector);
+			writebootimage(bootimage, bootfd,
+				fd, &currentsector, appendsectorinfo, &root);
+
+			close(bootfd);
+		}
 	}
 
 	fprintf(stderr, " * all ok\n");

tools/release.sh

@@ -19,6 +19,14 @@ PACKAGESOURCELIST=package_sources.install
 secs=`expr 32 '*' 64`
 export SHELL=/bin/sh
 
+RELEASERC=$HOME/.releaserc
+
+if [ -f $RELEASERC ]
+then	. $RELEASERC
+fi
+
+set -- $* $RELOPTS
+
 # SVN trunk repo
 TRUNK=https://gforge.cs.vu.nl/svn/minix/trunk
 
@@ -107,7 +115,7 @@ usr=/dev/c0d7p0s2
 RELEASEDIR=/usr/r
 RELEASEPACKAGE=${RELEASEDIR}/usr/install/packages
 RELEASEPACKAGESOURCES=${RELEASEDIR}/usr/install/package-sources
-IMAGE=../boot/boot
+IMAGE=../boot/cdbootblock
 ROOTIMAGE=rootimage
 CDFILES=/usr/tmp/cdreleasefiles
 sh tell_config OS_RELEASE . OS_VERSION >/tmp/rel.$$
@@ -394,7 +402,8 @@ fi
 if [ "$USB" -ne 0 ]; then
 	mv $bootimage $IMG
 else
-	writeisofs -s0x1000 -l MINIX -b $bootimage $boottype $CDFILES $IMG || exit 1
+	cp ../boot/boot $CDFILES
+	writeisofs -s0x0 -l MINIX -a boot -b $bootimage $boottype $CDFILES $IMG || exit 1
 
 	if [ "$HDEMU" -eq 0 ]
 	then
@@ -414,6 +423,8 @@ else
 		# Make sure there is no hole..! Otherwise the ISO format is
 		# unreadable.
 		partition -m $IMG 0 81:$isosects 81:$ROOTSECTS 81:$USRSECTS
+		echo "gzipping $IMG"
+		gzip $IMG
 	fi
 fi