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>

1 files changed, 13 insertions, 18 deletions

diff --git a/util-linux/fdisk.c b/util-linux/fdisk.c
index f28d4fdd2..076c5ca57 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) {