From 3bac4caa2bc64db313aaee54fffb90383e118517 Mon Sep 17 00:00:00 2001
From: Felix Janda <felix.janda@posteo.de>
Date: Thu, 22 Jan 2015 19:54:36 +0100
Subject: [PATCH] Remove direct _llseek code and require long filesystem libc.

---
 ChangeLog                       |  4 ++++
 INSTALL                         |  1 +
 configure.ac                    |  8 ++++++++
 grub-core/osdep/unix/hostdisk.c | 24 ------------------------
 4 files changed, 13 insertions(+), 24 deletions(-)

diff --git a/ChangeLog b/ChangeLog
index 2d57d83fa..024a876dd 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,7 @@
+2015-01-22  Felix Janda <felix.janda@posteo.de>
+
+	Remove direct _llseek code and require long filesystem libc.
+
 2015-01-20  Vladimir Serbinenko  <phcoder@gmail.com>
 
 	Remove potential division by 0 in gfxmenu.
diff --git a/INSTALL b/INSTALL
index b67cd7f34..f6f276c44 100644
--- a/INSTALL
+++ b/INSTALL
@@ -35,6 +35,7 @@ configuring the GRUB.
 * GNU binutils 2.9.1.0.23 or later
 * Flex 2.5.35 or later
 * Other standard GNU/Unix tools
+* a libc with large file support (e.g. glibc 2.1 or later)
 
 On GNU/Linux, you also need:
 
diff --git a/configure.ac b/configure.ac
index 31d2b0baf..fdddbaddc 100644
--- a/configure.ac
+++ b/configure.ac
@@ -366,6 +366,14 @@ case "$host_os" in
    ;;
 esac
 
+case "$host_os" in
+  cygwin | windows* | mingw32* | aros*)
+     ;;
+  *)
+     AC_CHECK_SIZEOF(off_t)
+     test x"$ac_cv_sizeof_off_t" = x8 || AC_MSG_ERROR([Large file support is required]);;
+esac
+
 if test x$USE_NLS = xno; then
   HOST_CFLAGS="$HOST_CFLAGS -fno-builtin-gettext"
 fi
diff --git a/grub-core/osdep/unix/hostdisk.c b/grub-core/osdep/unix/hostdisk.c
index 43b56ff31..b3bc0e425 100644
--- a/grub-core/osdep/unix/hostdisk.c
+++ b/grub-core/osdep/unix/hostdisk.c
@@ -48,11 +48,6 @@
 #ifdef __linux__
 # include <sys/ioctl.h>         /* ioctl */
 # include <sys/mount.h>
-# if !defined(__GLIBC__) || \
-        ((__GLIBC__ < 2) || ((__GLIBC__ == 2) && (__GLIBC_MINOR__ < 1)))
-/* Maybe libc doesn't have large file support.  */
-#  include <linux/unistd.h>     /* _llseek */
-# endif /* (GLIBC < 2) || ((__GLIBC__ == 2) && (__GLIBC_MINOR < 1)) */
 #endif /* __linux__ */
 
 grub_uint64_t
@@ -79,24 +74,6 @@ grub_util_get_fd_size (grub_util_fd_t fd, const char *name, unsigned *log_secsiz
   return st.st_size;
 }
 
-#if defined(__linux__) && (!defined(__GLIBC__) || \
-        ((__GLIBC__ < 2) || ((__GLIBC__ == 2) && (__GLIBC_MINOR__ < 1))))
-  /* Maybe libc doesn't have large file support.  */
-int
-grub_util_fd_seek (grub_util_fd_t fd, grub_uint64_t off)
-{
-  loff_t offset, result;
-  static int _llseek (uint filedes, ulong hi, ulong lo,
-		      loff_t *res, uint wh);
-  _syscall5 (int, _llseek, uint, filedes, ulong, hi, ulong, lo,
-	     loff_t *, res, uint, wh);
-
-  offset = (loff_t) off;
-  if (_llseek (fd, offset >> 32, offset & 0xffffffff, &result, SEEK_SET))
-    return -1;
-  return GRUB_ERR_NONE;
-}
-#else
 int
 grub_util_fd_seek (grub_util_fd_t fd, grub_uint64_t off)
 {
@@ -107,7 +84,6 @@ grub_util_fd_seek (grub_util_fd_t fd, grub_uint64_t off)
 
   return 0;
 }
-#endif
 
 
 /* Read LEN bytes from FD in BUF. Return less than or equal to zero if an