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-rw-r--r--lib/ext2fs/llseek.c145
1 files changed, 145 insertions, 0 deletions
diff --git a/lib/ext2fs/llseek.c b/lib/ext2fs/llseek.c
new file mode 100644
index 0000000..45f21d0
--- /dev/null
+++ b/lib/ext2fs/llseek.c
@@ -0,0 +1,145 @@
+/*
+ * llseek.c -- stub calling the llseek system call
+ *
+ * Copyright (C) 1994, 1995, 1996, 1997 Theodore Ts'o.
+ *
+ * %Begin-Header%
+ * This file may be redistributed under the terms of the GNU Library
+ * General Public License, version 2.
+ * %End-Header%
+ */
+
+#ifndef _LARGEFILE_SOURCE
+#define _LARGEFILE_SOURCE
+#endif
+#ifndef _LARGEFILE64_SOURCE
+#define _LARGEFILE64_SOURCE
+#endif
+
+#include "config.h"
+#if HAVE_SYS_TYPES_H
+#include <sys/types.h>
+#endif
+
+#if HAVE_ERRNO_H
+#include <errno.h>
+#endif
+#if HAVE_UNISTD_H
+#include <unistd.h>
+#endif
+#ifdef __MSDOS__
+#include <io.h>
+#endif
+#include "et/com_err.h"
+#include "ext2fs/ext2_io.h"
+
+#ifdef __linux__
+
+#if defined(HAVE_LSEEK64) && defined(HAVE_LSEEK64_PROTOTYPE)
+
+#define my_llseek lseek64
+
+#else
+#if defined(HAVE_LLSEEK)
+#include <sys/syscall.h>
+
+#ifndef HAVE_LLSEEK_PROTOTYPE
+extern long long llseek (int fd, long long offset, int origin);
+#endif
+
+#define my_llseek llseek
+
+#else /* ! HAVE_LLSEEK */
+
+#if SIZEOF_LONG == SIZEOF_LONG_LONG || _FILE_OFFSET_BITS+0 == 64
+
+#define my_llseek lseek
+
+#else /* SIZEOF_LONG != SIZEOF_LONG_LONG */
+
+#include <linux/unistd.h>
+
+#ifndef __NR__llseek
+#define __NR__llseek 140
+#endif
+
+#ifndef __i386__
+static int _llseek (unsigned int, unsigned long,
+ unsigned long, ext2_loff_t *, unsigned int);
+
+static _syscall5(int,_llseek,unsigned int,fd,unsigned long,offset_high,
+ unsigned long, offset_low,ext2_loff_t *,result,
+ unsigned int, origin);
+#endif
+
+static ext2_loff_t my_llseek (int fd, ext2_loff_t offset, int origin)
+{
+ ext2_loff_t result;
+ int retval;
+
+#ifndef __i386__
+ retval = _llseek(fd, ((unsigned long long) offset) >> 32,
+#else
+ retval = syscall(__NR__llseek, fd, (unsigned long long) (offset >> 32),
+#endif
+ ((unsigned long long) offset) & 0xffffffff,
+ &result, origin);
+ return (retval == -1 ? (ext2_loff_t) retval : result);
+}
+
+#endif /* SIZE_LONG == SIZEOF_LONG_LONG */
+
+#endif /* HAVE_LLSEEK */
+#endif /* defined(HAVE_LSEEK64) && defined(HAVE_LSEEK64_PROTOTYPE) */
+
+ext2_loff_t ext2fs_llseek (int fd, ext2_loff_t offset, int origin)
+{
+#if SIZEOF_OFF_T >= SIZEOF_LONG_LONG
+ return my_llseek (fd, offset, origin);
+#else
+ ext2_loff_t result;
+ static int do_compat = 0;
+
+ if (do_compat)
+ goto fallback;
+
+ result = my_llseek (fd, offset, origin);
+ if (result == -1 && errno == ENOSYS) {
+ /*
+ * Just in case this code runs on top of an old kernel
+ * which does not support the llseek system call
+ */
+ do_compat++;
+ fallback:
+ if (offset < ((ext2_loff_t) 1 << ((sizeof(off_t)*8) -1)))
+ return lseek(fd, (off_t) offset, origin);
+ errno = EINVAL;
+ return -1;
+ }
+ return result;
+#endif
+}
+
+#else /* !linux */
+
+#ifndef EINVAL
+#define EINVAL EXT2_ET_INVALID_ARGUMENT
+#endif
+
+ext2_loff_t ext2fs_llseek (int fd, ext2_loff_t offset, int origin)
+{
+#if defined(HAVE_LSEEK64) && defined(HAVE_LSEEK64_PROTOTYPE)
+ return lseek64 (fd, offset, origin);
+#else
+ if ((sizeof(off_t) < sizeof(ext2_loff_t)) &&
+ (offset >= ((ext2_loff_t) 1 << ((sizeof(off_t)*8) -1)))) {
+ errno = EINVAL;
+ return -1;
+ }
+ return lseek (fd, (off_t) offset, origin);
+#endif
+}
+
+#endif /* linux */
+
+