From 0e809f9c0845333d2d9f3456b6a4fc86bcd80cb1 Mon Sep 17 00:00:00 2001
From: Ben Gras <ben@minix3.org>
Date: Fri, 9 Sep 2005 13:23:24 +0000
Subject: [PATCH] -m<MB> feature to know how big things have to me.

write 2kB of zeroes at the start of new partitions to clear out old gunk
(such as subpartitioning or old boot code).
---
 commands/ibm/autopart.c | 32 ++++++++++++++++++++++++--------
 1 file changed, 24 insertions(+), 8 deletions(-)

diff --git a/commands/ibm/autopart.c b/commands/ibm/autopart.c
index 9b4e99dd0..05eedb25f 100755
--- a/commands/ibm/autopart.c
+++ b/commands/ibm/autopart.c
@@ -59,8 +59,9 @@ Num Sort   Type
 #define DEV_FD0		0x200		/* Device number of /dev/fd0 */
 #define DEV_C0D0	0x300		/* Device number of /dev/c0d0 */
 
-#define MIN_REGION_MB	500
-#define MIN_REGION_SECTORS (1024*1024*MIN_REGION_MB/SECTOR_SIZE)
+int min_region_mb = 500;
+
+#define MIN_REGION_SECTORS (1024*1024*min_region_mb/SECTOR_SIZE)
 
 #define MAX_REGION_MB	4095
 #define MAX_REGION_SECTORS (1024*(1024/SECTOR_SIZE)*MAX_REGION_MB)
@@ -2509,7 +2510,7 @@ select_disk(void)
 }
 
 int
-scribble_region(region_t *reg, struct part_entry **pe)
+scribble_region(region_t *reg, struct part_entry **pe, int *made_new)
 {
 	int ex, trunc = 0, changed = 0, i;
 	struct part_entry *newpart;
@@ -2527,7 +2528,8 @@ scribble_region(region_t *reg, struct part_entry **pe)
 			changed = 1;
 			cylinderalign(reg);
 		}
-	}
+		if(made_new) *made_new = 1;
+	} else if(made_new) *made_new = 0;
 #if 0
 	if(trunc) {
 		printf("\nWill only use %dMB.\n", MAX_REGION_MB);
@@ -2605,7 +2607,7 @@ do_autopart(int resultfd)
 	struct part_entry *pe;
 	char sure[50];
 	struct part_entry orig_table[1 + NR_PARTITIONS];
-	int region, disk;
+	int region, disk, newp;
 
 	nordonly = 1; 
 
@@ -2629,13 +2631,12 @@ do_autopart(int resultfd)
 	} while(!r);	/* Back to step 2. */
 
 	/* Write things. */
-	if(scribble_region(r, &pe)) {
+	if(scribble_region(r, &pe, &newp)) {
 		char *name;
 		int i, found = -1;
 		char partbuf[100], devname[100];
 		struct part_entry *tpe;
 
-
 		printstep(3, "Confirm your choices");
 
 		region =  (int)(r-regions); 
@@ -2708,6 +2709,18 @@ do_autopart(int resultfd)
 			fprintf(stderr, "Autopart internal error (disk sanity check failed).\n");
 			exit(1);
 		}
+
+		if(newp) {
+			int fd;
+			if((fd=open(devname, O_WRONLY)) < 0) {
+				perror(devname);
+			} else {
+				/* Clear any subpartitioning. */
+				static char sub[2048];
+				write(fd, sub, sizeof(sub));
+				close(fd);
+			}
+		}
 		return 0;
 	}
 
@@ -2782,8 +2795,11 @@ int main(int argc, char **argv)
      } else {
      	int c;
      	/* autopart uses getopt() */
-     	while((c = getopt(argc, argv, "f:")) != EOF) {
+     	while((c = getopt(argc, argv, "m:f:")) != EOF) {
      		switch(c) {
+			case 'm':
+				min_region_mb = atoi(optarg);
+				break;
      			case 'f':
 				/* Make sure old data file is gone. */
      				unlink(optarg);
-- 
2.44.0