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-rw-r--r--libblkid/src/llseek.c147
1 files changed, 147 insertions, 0 deletions
diff --git a/libblkid/src/llseek.c b/libblkid/src/llseek.c
new file mode 100644
index 0000000..d5c494e
--- /dev/null
+++ b/libblkid/src/llseek.c
@@ -0,0 +1,147 @@
+/*
+ * 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 Lesser General Public License.
+ * %End-Header%
+ */
+
+#ifndef _LARGEFILE_SOURCE
+# define _LARGEFILE_SOURCE
+#endif
+
+#ifndef _LARGEFILE64_SOURCE
+# define _LARGEFILE64_SOURCE
+#endif
+
+#ifdef HAVE_SYS_TYPES_H
+#include <sys/types.h>
+#endif
+
+#ifdef HAVE_ERRNO_H
+#include <errno.h>
+#endif
+#ifdef HAVE_UNISTD_H
+#include <unistd.h>
+#endif
+#ifdef __MSDOS__
+#include <io.h>
+#endif
+
+#include "blkidP.h"
+
+#ifdef __linux__
+
+#if defined(HAVE_LSEEK64) && defined(HAVE_LSEEK64_PROTOTYPE)
+
+#define my_llseek lseek64
+
+#elif defined(HAVE_LLSEEK)
+#include <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
+
+#define 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,
+ blkid_loff_t *, unsigned int);
+
+static _syscall5(int, _llseek, unsigned int, fd, unsigned long, offset_high,
+ unsigned long, offset_low, blkid_loff_t *, result,
+ unsigned int, origin)
+#endif
+
+static blkid_loff_t my_llseek(int fd, blkid_loff_t offset, int origin)
+{
+ blkid_loff_t result;
+ int retval;
+
+#ifndef __i386__
+ retval = _llseek(fd, ((unsigned long long) offset) >> 32,
+ ((unsigned long long)offset) & 0xffffffff,
+ &result, origin);
+#else
+ retval = syscall(__NR__llseek, fd, ((unsigned long long) offset) >> 32,
+ ((unsigned long long)offset) & 0xffffffff,
+ &result, origin);
+#endif
+ return (retval == -1 ? (blkid_loff_t) retval : result);
+}
+
+#endif /* __alpha__ || __ia64__ */
+
+#endif /* HAVE_LLSEEK */
+
+blkid_loff_t blkid_llseek(int fd, blkid_loff_t offset, int whence)
+{
+ blkid_loff_t result;
+ static int do_compat = 0;
+
+ if ((sizeof(off_t) >= sizeof(blkid_loff_t)) ||
+ (offset < ((blkid_loff_t) 1 << ((sizeof(off_t)*8) -1))))
+ return lseek(fd, (off_t) offset, whence);
+
+ if (do_compat) {
+ errno = EOVERFLOW;
+ return -1;
+ }
+
+ result = my_llseek(fd, offset, whence);
+ 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++;
+ errno = EOVERFLOW;
+ }
+ return result;
+}
+
+#else /* !linux */
+
+#ifndef EOVERFLOW
+#ifdef EXT2_ET_INVALID_ARGUMENT
+#define EOVERFLOW EXT2_ET_INVALID_ARGUMENT
+#else
+#define EOVERFLOW 112
+#endif
+#endif
+
+blkid_loff_t blkid_llseek(int fd, blkid_loff_t offset, int origin)
+{
+#if defined(HAVE_LSEEK64) && defined(HAVE_LSEEK64_PROTOTYPE)
+ return lseek64 (fd, offset, origin);
+#else
+ if ((sizeof(off_t) < sizeof(blkid_loff_t)) &&
+ (offset >= ((blkid_loff_t) 1 << ((sizeof(off_t)*8) - 1)))) {
+ errno = EOVERFLOW;
+ return -1;
+ }
+ return lseek(fd, (off_t) offset, origin);
+#endif
+}
+
+#endif /* linux */
+
+