nilfs-resize: switch singular/plural forms of "segment" in message text

When outputting the number segments in messages, switch between
singular and plural forms of string "segment" depending on the count.

Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>

Author: konis

sbin/nilfs-resize.c

@@ -458,15 +458,16 @@ static int nilfs_resize_check_free_space(struct nilfs *nilfs,
 			+ nrsvsegs;
 		nbytes = nilfs_resize_calc_size_of_segments(nsegs);
 		myprintf("Error: the filesystem does not have enough free space.\n"
-			 "       At least %llu more segments (%llu bytes) are required.\n",
-			 nsegs, nbytes);
+			 "       At least %llu more segment%s (%llu bytes) %s required.\n",
+			 nsegs, nsegs != 1 ? "s" : "", nbytes,
+			 nsegs != 1 ? "are" : "is");
 		return -1;
 	} else if (verbose) {
 		nsegs = sustat.ss_ncleansegs - (sustat.ss_nsegs - newnsegs)
 			- nrsvsegs;
 		nbytes = nilfs_resize_calc_size_of_segments(nsegs);
-		myprintf("%llu free segments (%llu bytes) will be left after shrinkage.\n",
-			 nsegs, nbytes);
+		myprintf("%llu free segment%s (%llu bytes) will be left after shrinkage.\n",
+			 nsegs, nsegs != 1 ? "s" : "", nbytes);
 	}
 	return 0;
 }
@@ -1258,8 +1259,10 @@ static int nilfs_shrink_online(struct nilfs *nilfs, const char *device,
 		goto out;
 
 	if (newnsegs < sustat.ss_nsegs) {
-		myprintf("%llu segments will be truncated from segnum %llu.\n",
-			 (unsigned long long)sustat.ss_nsegs - newnsegs,
+		uint64_t truncsegs = sustat.ss_nsegs - newnsegs;
+
+		myprintf("%llu segment%s will be truncated from segnum %llu.\n",
+			 (unsigned long long)truncsegs, truncsegs != 1 ? "s" : "",
 			 (unsigned long long)newnsegs);
 	} else if (newnsegs == sustat.ss_nsegs) {
 		myprintf("No segments will be truncated.\n");