ext2fs: Use 64bit lseek when _FILE_OFFSET_BITS is 64

[thirdparty/e2fsprogs.git] / lib / ext2fs / llseek.c

diff --git a/lib/ext2fs/llseek.c b/lib/ext2fs/llseek.c
index 02e0ede8706168f3ea822f264a8c5e74019d3547..45f21d09d6e09295b15d7056b81c1427b636b3b8 100644 (file)
--- a/lib/ext2fs/llseek.c
+++ b/lib/ext2fs/llseek.c
@@ -1,30 +1,61 @@
 /*
  * llseek.c -- stub calling the llseek system call
  *
- * Copyright (C) 1994 Remy Card.  This file may be redistributed
- * under the terms of the GNU Public License.
+ * 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/io.h"
+#include "ext2fs/ext2_io.h"
 
 #ifdef __linux__
 
-#ifdef HAVE_LLSEEK
-#include <unistd.h>
-#include <syscall.h>
+#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 */
+#else  /* ! HAVE_LLSEEK */
 
-#ifdef __alpha__
+#if SIZEOF_LONG == SIZEOF_LONG_LONG || _FILE_OFFSET_BITS+0 == 64
 
-#define llseek lseek
+#define my_llseek lseek
 
-#else /* !__alpha__ */
+#else /* SIZEOF_LONG != SIZEOF_LONG_LONG */
 
 #include <linux/unistd.h>
 
@@ -32,67 +63,81 @@
 #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)
+                unsigned int, origin);
+#endif
 
-static ext2_loff_t llseek (unsigned int fd, ext2_loff_t offset,
-               unsigned int origin)
+static ext2_loff_t my_llseek (int fd, ext2_loff_t offset, int origin)
 {
        ext2_loff_t result;
        int retval;
 
-       retval = _llseek (fd, ((unsigned long long) offset) >> 32,
-                       ((unsigned long long) offset) & 0xffffffff,
+#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 /* HAVE_LLSEEK */
+#endif /* SIZE_LONG == SIZEOF_LONG_LONG */
 
-#endif /* __alpha__ */
+#endif /* HAVE_LLSEEK */
+#endif /* defined(HAVE_LSEEK64) && defined(HAVE_LSEEK64_PROTOTYPE) */
 
-ext2_loff_t ext2_llseek (unsigned int fd, ext2_loff_t offset,
-                        unsigned int origin)
+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 ((sizeof(off_t) >= sizeof(ext2_loff_t)) ||
-           (offset < ((ext2_loff_t) 1 << ((sizeof(off_t)*8) -1))))
-               return lseek(fd, (off_t) offset, origin);
+       if (do_compat)
+               goto fallback;
 
-       if (do_compat) {
-               errno = EINVAL;
-               return -1;
-       }
-       
-       result = llseek (fd, offset, origin);
+       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 */
 
-ext2_loff_t ext2_llseek (unsigned int fd, ext2_loff_t offset,
-                        unsigned int origin)
+#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 */