From 8c3fd8eea724a1490d29937b1d23cde259bf63cb Mon Sep 17 00:00:00 2001
From: Vladimir 'phcoder' Serbinenko <phcoder@gmail.com>
Date: Mon, 7 Jan 2013 11:27:18 +0100
Subject: [PATCH 088/364] * grub-core/fs/minix.c (grub_minix_read_file):
Simplify arithmetics.
---
ChangeLog | 4 ++++
grub-core/fs/minix.c | 8 ++++----
2 files changed, 8 insertions(+), 4 deletions(-)
diff --git a/ChangeLog b/ChangeLog
index af29161..cdb3f3d 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,7 @@
+2013-01-07 Vladimir Serbinenko <phcoder@gmail.com>
+
+ * grub-core/fs/minix.c (grub_minix_read_file): Simplify arithmetics.
+
2013-01-05 Vladimir Serbinenko <phcoder@gmail.com>
* grub-core/fs/ext2.c (grub_ext2_read_block): Use shifts rather than
diff --git a/grub-core/fs/minix.c b/grub-core/fs/minix.c
index 1e1c13b..a622533 100644
--- a/grub-core/fs/minix.c
+++ b/grub-core/fs/minix.c
@@ -261,12 +261,12 @@ grub_minix_read_file (struct grub_minix_data *data,
/* Adjust len so it we can't read past the end of the file. */
if (len + pos > GRUB_MINIX_INODE_SIZE (data))
len = GRUB_MINIX_INODE_SIZE (data) - pos;
+ if (len == 0)
+ return 0;
/* Files are at most 2G/4G - 1 bytes on minixfs. Avoid 64-bit division. */
- blockcnt = ((grub_uint32_t) ((len + pos
- + (data->block_size << GRUB_DISK_SECTOR_BITS)
- - 1)
- >> GRUB_DISK_SECTOR_BITS)) / data->block_size;
+ blockcnt = ((grub_uint32_t) ((len + pos - 1)
+ >> GRUB_DISK_SECTOR_BITS)) / data->block_size + 1;
posblock = (((grub_uint32_t) pos)
/ (data->block_size << GRUB_DISK_SECTOR_BITS));
blockoff = (((grub_uint32_t) pos)
--
1.8.1.4