fdisk: avoid overflow in "mega/gigabytes" calculation, code shrink

function                                             old     new   delta
list_disk_geometry                                   175     145     -30

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>

4 files changed, 29 insertions, 34 deletions

diff --git a/util-linux/fdisk.c b/util-linux/fdisk.c
index f28d4fd..076c5ca 100644
--- a/util-linux/fdisk.c
+++ b/util-linux/fdisk.c
@@ -299,9 +299,6 @@ static int get_boot(enum action what);
 static int get_boot(void);
 #endif
 
-#define PLURAL   0
-#define SINGULAR 1
-
 static sector_t get_start_sect(const struct partition *p);
 static sector_t get_nr_sects(const struct partition *p);
 
@@ -597,12 +594,10 @@ get_part_table(int i)
 	return ptes[i].part_table;
 }
 
-static const char *
-str_units(int n)
-{      /* n==1: use singular */
-	if (n == 1)
-		return display_in_cyl_units ? "cylinder" : "sector";
-	return display_in_cyl_units ? "cylinders" : "sectors";
+static ALWAYS_INLINE const char *
+str_units(void)
+{
+	return display_in_cyl_units ? "cylinder" : "sector";
 }
 
 static int
@@ -1778,8 +1773,8 @@ change_units(void)
 {
 	display_in_cyl_units = !display_in_cyl_units;
 	update_units();
-	printf("Changing display/entry units to %s\n",
-		str_units(PLURAL));
+	printf("Changing display/entry units to %ss\n",
+		str_units());
 }
 
 static void
@@ -2030,8 +2025,7 @@ check_consistency(const struct partition *p, int partition)
 static void
 list_disk_geometry(void)
 {
-	ullong bytes = ((ullong)total_number_of_sectors << 9);
-	ullong xbytes = bytes / (1024*1024);
+	ullong xbytes = total_number_of_sectors / (1024*1024 / 512);
 	char x = 'M';
 
 	if (xbytes >= 10000) {
@@ -2041,11 +2035,12 @@ list_disk_geometry(void)
 	}
 	printf("Disk %s: %llu %cB, %llu bytes, %"SECT_FMT"u sectors\n"
 		"%u cylinders, %u heads, %u sectors/track\n"
-		"Units: %s of %u * %u = %u bytes\n\n",
+		"Units: %ss of %u * %u = %u bytes\n"
+		"\n",
 		disk_device, xbytes, x,
-		bytes, total_number_of_sectors,
+		((ullong)total_number_of_sectors * 512), total_number_of_sectors,
 		g_cylinders, g_heads, g_sectors,
-		str_units(PLURAL),
+		str_units(),
 		units_per_sector, sector_size, units_per_sector * sector_size
 	);
 }
@@ -2486,7 +2481,7 @@ add_partition(int n, int sys)
 		for (i = 0; i < g_partitions; i++)
 			first[i] = (cround(first[i]) - 1) * units_per_sector;
 
-	snprintf(mesg, sizeof(mesg), "First %s", str_units(SINGULAR));
+	snprintf(mesg, sizeof(mesg), "First %s", str_units());
 	do {
 		temp = start;
 		for (i = 0; i < g_partitions; i++) {
@@ -2548,7 +2543,7 @@ add_partition(int n, int sys)
 	} else {
 		snprintf(mesg, sizeof(mesg),
 			 "Last %s or +size{,K,M,G,T}",
-			 str_units(SINGULAR)
+			 str_units()
 		);
 		stop = read_int(cround(start), cround(limit), cround(limit), cround(start), mesg);
 		if (display_in_cyl_units) {
diff --git a/util-linux/fdisk_osf.c b/util-linux/fdisk_osf.c
index 1328c1f..92180b2 100644
--- a/util-linux/fdisk_osf.c
+++ b/util-linux/fdisk_osf.c
@@ -470,7 +470,7 @@ xbsd_new_part(void)
 	end = xbsd_dlabel.d_secperunit - 1;
 #endif
 
-	snprintf(mesg, sizeof(mesg), "First %s", str_units(SINGULAR));
+	snprintf(mesg, sizeof(mesg), "First %s", str_units());
 	begin = read_int(bsd_cround(begin), bsd_cround(begin), bsd_cround(end),
 		0, mesg);
 
@@ -478,7 +478,7 @@ xbsd_new_part(void)
 		begin = (begin - 1) * xbsd_dlabel.d_secpercyl;
 
 	snprintf(mesg, sizeof(mesg), "Last %s or +size or +sizeM or +sizeK",
-		str_units(SINGULAR));
+		str_units());
 	end = read_int(bsd_cround(begin), bsd_cround(end), bsd_cround(end),
 		bsd_cround(begin), mesg);
 
diff --git a/util-linux/fdisk_sgi.c b/util-linux/fdisk_sgi.c
index 0e5491a..c90c801 100644
--- a/util-linux/fdisk_sgi.c
+++ b/util-linux/fdisk_sgi.c
@@ -295,19 +295,19 @@ sgi_list_table(int xtra)
 			"%u cylinders, %u physical cylinders\n"
 			"%u extra sects/cyl, interleave %u:1\n"
 			"%s\n"
-			"Units = %s of %u * 512 bytes\n\n",
+			"Units = %ss of %u * 512 bytes\n\n",
 			disk_device, g_heads, g_sectors, g_cylinders,
 			SGI_SSWAP16(sgiparam.pcylcount),
 			SGI_SSWAP16(sgiparam.sparecyl),
 			SGI_SSWAP16(sgiparam.ilfact),
 			(char *)sgilabel,
-			str_units(PLURAL), units_per_sector);
+			str_units(), units_per_sector);
 	} else {
 		printf("\nDisk %s (SGI disk label): "
 			"%u heads, %u sectors, %u cylinders\n"
-			"Units = %s of %u * 512 bytes\n\n",
+			"Units = %ss of %u * 512 bytes\n\n",
 			disk_device, g_heads, g_sectors, g_cylinders,
-			str_units(PLURAL), units_per_sector );
+			str_units(), units_per_sector );
 	}
 
 	w = strlen(disk_device);
@@ -720,7 +720,7 @@ sgi_add_partition(int n, int sys)
 		printf("You got a partition overlap on the disk. Fix it first!\n");
 		return;
 	}
-	snprintf(mesg, sizeof(mesg), "First %s", str_units(SINGULAR));
+	snprintf(mesg, sizeof(mesg), "First %s", str_units());
 	while (1) {
 		if (sys == SGI_VOLUME) {
 			last = sgi_get_lastblock();
@@ -746,7 +746,7 @@ sgi_add_partition(int n, int sys)
 		printf("You will get a partition overlap on the disk. "
 				"Fix it first!\n");
 	}
-	snprintf(mesg, sizeof(mesg), " Last %s", str_units(SINGULAR));
+	snprintf(mesg, sizeof(mesg), " Last %s", str_units());
 	last = read_int(scround(first), scround(last)-1, scround(last)-1,
 			scround(first), mesg)+1;
 	if (display_in_cyl_units)
diff --git a/util-linux/fdisk_sun.c b/util-linux/fdisk_sun.c
index 3697a69..29d7c28 100644
--- a/util-linux/fdisk_sun.c
+++ b/util-linux/fdisk_sun.c
@@ -491,7 +491,7 @@ add_sun_partition(int n, int sys)
 			return;
 		}
 	}
-	snprintf(mesg, sizeof(mesg), "First %s", str_units(SINGULAR));
+	snprintf(mesg, sizeof(mesg), "First %s", str_units());
 	while (1) {
 		if (whole_disk)
 			first = read_int(0, 0, 0, 0, mesg);
@@ -546,7 +546,7 @@ and is of type 'Whole disk'\n");
 	}
 	snprintf(mesg, sizeof(mesg),
 		"Last %s or +size or +sizeM or +sizeK",
-		str_units(SINGULAR));
+		str_units());
 	if (whole_disk)
 		last = read_int(scround(stop2), scround(stop2), scround(stop2),
 				0, mesg);
@@ -567,8 +567,8 @@ and is of type 'Whole disk'\n");
 "You haven't covered the whole disk with the 3rd partition,\n"
 "but your value %u %s covers some other partition.\n"
 "Your entry has been changed to %u %s\n",
-				scround(last), str_units(SINGULAR),
-				scround(stop), str_units(SINGULAR));
+				scround(last), str_units(),
+				scround(stop), str_units());
 			last = stop;
 		}
 	} else if (!whole_disk && last > stop)
@@ -636,20 +636,20 @@ sun_list_table(int xtra)
 		"%u cylinders, %u alternate cylinders, %u physical cylinders\n"
 		"%u extra sects/cyl, interleave %u:1\n"
 		"%s\n"
-		"Units = %s of %u * 512 bytes\n\n",
+		"Units = %ss of %u * 512 bytes\n\n",
 			disk_device, g_heads, g_sectors, SUN_SSWAP16(sunlabel->rspeed),
 			g_cylinders, SUN_SSWAP16(sunlabel->nacyl),
 			SUN_SSWAP16(sunlabel->pcylcount),
 			SUN_SSWAP16(sunlabel->sparecyl),
 			SUN_SSWAP16(sunlabel->ilfact),
 			(char *)sunlabel,
-			str_units(PLURAL), units_per_sector);
+			str_units(), units_per_sector);
 	else
 		printf(
 	"\nDisk %s (Sun disk label): %u heads, %u sectors, %u cylinders\n"
-	"Units = %s of %u * 512 bytes\n\n",
+	"Units = %ss of %u * 512 bytes\n\n",
 			disk_device, g_heads, g_sectors, g_cylinders,
-			str_units(PLURAL), units_per_sector);
+			str_units(), units_per_sector);
 
 	printf("%*s Flag    Start       End    Blocks   Id  System\n",
 		w + 1, "Device");