+ add u_long sector_size to struct disk (documented in libdisk.3)

+ make Open_Disk sense the sector size by trying 512, 1024 and 2048
  in this order. This makes the kernel note that
  dscheck(cd1): bio_bcount 512 is not on a sector boundary (ssize 2048)
  dscheck(cd1): bio_bcount 1024 is not on a sector boundary (ssize 2048)
  if 2048 is the sector size. If this worries anyone: the message is from
  /usr/src/sys/kern/subr_diskslice.c and shutups are to be placed there.
+ Have read_block and write_block use an additional parameter, the
  sector size.
+ replace all barfout calls with return NULL, 0, __LINE__, etc.
  Note that this does NOT emit diagnostics. More often than not,
  you don't want library functions to scribble on stderr -- it may
  not even be available. The right thing is to propagate the error
  condition to upper management. The app should take care of errors.
+ use d1->sector_size instead of 512 in various places. I've left many
  places untouched, especially those writing MBRs. I simply added
  another arg hardcoded as 512. This is because I would not know what
  I'm doing... I felt this approach would be reasonably backward
  compatible and not introduce any new bugs in critical software.
  Famous last words. Messing with MBRs might soon put me in the same
  screwup meister category as, uh, never mind.  :-)
+ bump the max no of disks from 20 to 32 (due to PR 24503).

PR:		8434 / 8436 / 24503
Submitted by:	Jens Schweikhardt <schweikh@schweikhardt.net>

1 files changed, 32 insertions, 20 deletions

diff --git a/lib/libdisk/disk.c b/lib/libdisk/disk.c
index 36b8986..6900443 100644
--- a/lib/libdisk/disk.c
+++ b/lib/libdisk/disk.c
@@ -60,8 +60,9 @@ Int_Open_Disk(const char *name, u_long size)
 	int i,fd;
 	struct diskslices ds;
 	struct disklabel dl;
-	char device[64];
+	char device[64], *buf;
 	struct disk *d;
+	u_long sector_size;
 #ifdef PC98
 	unsigned char *p;
 #else
@@ -74,7 +75,7 @@ Int_Open_Disk(const char *name, u_long size)
 	strcat(device, name);
 
 	d = (struct disk *)malloc(sizeof *d);
-	if(!d) barfout(1, "malloc failed");
+	if(!d) return NULL;
 	memset(d, 0, sizeof *d);
 
 	fd = open(device, O_RDONLY);
@@ -104,7 +105,7 @@ Int_Open_Disk(const char *name, u_long size)
 	printf("\n");
 #endif
 
-/* XXX --- ds.dss_slice[WHOLE_DISK_SLCIE].ds.size of MO disk is wrong!!! */
+/* XXX --- ds.dss_slice[WHOLE_DISK_SLICE].ds.size of MO disk is wrong!!! */
 #ifdef PC98
 	if (!size)
 		size = dl.d_ncylinders * dl.d_ntracks * dl.d_nsectors;
@@ -113,10 +114,23 @@ Int_Open_Disk(const char *name, u_long size)
 		size = ds.dss_slices[WHOLE_DISK_SLICE].ds_size;
 #endif
 
+	/* determine media sector size */
+	if ((buf = malloc(MAX_SEC_SIZE)) == NULL)
+		return NULL;
+	for (sector_size = MIN_SEC_SIZE; sector_size <= MAX_SEC_SIZE; sector_size *= 2) {
+		if (read(fd, buf, sector_size) == sector_size) {
+			d->sector_size = sector_size;
+			break;
+		}
+	}
+	free (buf);
+	if (sector_size > MAX_SEC_SIZE)
+		return NULL; /* could not determine sector size */
+
 #ifdef PC98
-	p = (unsigned char*)read_block(fd, 1);
+	p = (unsigned char*)read_block(fd, 1, sector_size);
 #else
-	p = read_block(fd, 0);
+	p = read_block(fd, 0, sector_size);
 	dp = (struct dos_partition*)(p + DOSPARTOFF);
 	for (i = 0; i < NDOSPART; i++) {
 		if (Read_Int32(&dp->dp_start) >= size)
@@ -416,7 +430,7 @@ Clone_Disk(struct disk *d)
 	struct disk *d2;
 
 	d2 = (struct disk*) malloc(sizeof *d2);
-	if(!d2) barfout(1, "malloc failed");
+	if(!d2) return NULL;
 	*d2 = *d;
 	d2->name = strdup(d2->name);
 	d2->chunks = Clone_Chunk(d2->chunks);
@@ -490,7 +504,7 @@ Disk_Names()
 	    disklist = (char *)malloc(listsize);
 	    error = sysctlbyname("kern.disks", disklist, &listsize, NULL, 0);
 	    if (error) 
-		    barfout(1, "sysctlbyname(\"kern.disks\") failed");
+		    return NULL;
 	    k = 0;
 	    for (dp = disks; ((*dp = strsep(&disklist, " ")) != NULL) && k < MAX_NO_DISKS; k++, dp++);
 	    return disks;
@@ -531,8 +545,7 @@ Set_Boot_Mgr(struct disk *d, const u_char *b, const size_t s)
 #endif
 {
 #ifdef PC98
-	/* XXX - assumes sector size of 512 */
-	if (bootipl_size % 512 != 0)
+	if (bootipl_size % d->sector_size != 0)
 		return;
 	if (d->bootipl)
 		free(d->bootipl);
@@ -541,12 +554,11 @@ Set_Boot_Mgr(struct disk *d, const u_char *b, const size_t s)
 	} else {
 		d->bootipl_size = bootipl_size;
 		d->bootipl = malloc(bootipl_size);
-		if(!d->bootipl) barfout(1, "malloc failed");
+		if(!d->bootipl) return;
 		memcpy(d->bootipl, bootipl, bootipl_size);
 	}
 
-	/* XXX - assumes sector size of 512 */
-	if (bootmenu_size % 512 != 0)
+	if (bootmenu_size % d->sector_size != 0)
 		return;
 	if (d->bootmenu)
 		free(d->bootmenu);
@@ -555,12 +567,11 @@ Set_Boot_Mgr(struct disk *d, const u_char *b, const size_t s)
 	} else {
 		d->bootmenu_size = bootmenu_size;
 		d->bootmenu = malloc(bootmenu_size);
-		if(!d->bootmenu) barfout(1, "malloc failed");
+		if(!d->bootmenu) return;
 		memcpy(d->bootmenu, bootmenu, bootmenu_size);
 	}
 #else
-	/* XXX - assumes sector size of 512 */
-	if (s % 512 != 0)
+	if (s % d->sector_size != 0)
 		return;
 	if (d->bootmgr)
 		free(d->bootmgr);
@@ -569,30 +580,31 @@ Set_Boot_Mgr(struct disk *d, const u_char *b, const size_t s)
 	} else {
 		d->bootmgr_size = s;
 		d->bootmgr = malloc(s);
-		if(!d->bootmgr) barfout(1, "malloc failed");
+		if(!d->bootmgr) return;
 		memcpy(d->bootmgr, b, s);
 	}
 #endif
 }
 
-void
+int
 Set_Boot_Blocks(struct disk *d, const u_char *b1, const u_char *b2)
 {
 #if defined(__i386__)
 	if (d->boot1) free(d->boot1);
 	d->boot1 = malloc(512);
-	if(!d->boot1) barfout(1, "malloc failed");
+	if(!d->boot1) return -1;
 	memcpy(d->boot1, b1, 512);
 	if (d->boot2) free(d->boot2);
 	d->boot2 = malloc(15 * 512);
-	if(!d->boot2) barfout(1, "malloc failed");
+	if(!d->boot2) return -1;
 	memcpy(d->boot2, b2, 15 * 512);
 #elif defined(__alpha__)
 	if (d->boot1) free(d->boot1);
 	d->boot1 = malloc(15 * 512);
-	if(!d->boot1) barfout(1, "malloc failed");
+	if(!d->boot1) return -1;
 	memcpy(d->boot1, b1, 15 * 512);
 #endif
+	return 0;
 }
 
 const char *