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 93409dd05d1f31585541c2202957e22b2515dece..45f21d09d6e09295b15d7056b81c1427b636b3b8 100644 (file)
--- a/lib/ext2fs/llseek.c
+++ b/lib/ext2fs/llseek.c
@@ -4,17 +4,26 @@
  * Copyright (C) 1994, 1995, 1996, 1997 Theodore Ts'o.
  *
  * %Begin-Header%
- * This file may be redistributed under the terms of the GNU Public
- * License.
+ * 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>
-#include <stdlib.h>
+#endif
 #if HAVE_UNISTD_H
 #include <unistd.h>
 #endif
@@ -26,25 +35,27 @@
 
 #ifdef __linux__
 
-#ifdef HAVE_LLSEEK
-#if HAVE_UNISTD_H
-#include <unistd.h>
-#endif
-#include <syscall.h>
+#if defined(HAVE_LSEEK64) && defined(HAVE_LSEEK64_PROTOTYPE)
+
+#define my_llseek lseek64
+
+#else
+#if defined(HAVE_LLSEEK)
+#include <sys/syscall.h>
 
-#if (__GLIBC__ == 2)
-ext2_loff_t llseek (int fd, ext2_loff_t offset, int origin);
+#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>
 
@@ -58,7 +69,7 @@ static int _llseek (unsigned int, unsigned long,
 
 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 my_llseek (int fd, ext2_loff_t offset, int origin)
@@ -68,7 +79,7 @@ static ext2_loff_t my_llseek (int fd, ext2_loff_t offset, int origin)
 
 #ifndef __i386__
        retval = _llseek(fd, ((unsigned long long) offset) >> 32,
-#else                    
+#else
        retval = syscall(__NR__llseek, fd, (unsigned long long) (offset >> 32),
 #endif
                          ((unsigned long long) offset) & 0xffffffff,
@@ -76,24 +87,22 @@ static ext2_loff_t my_llseek (int fd, ext2_loff_t offset, int 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 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 = my_llseek (fd, offset, origin);
        if (result == -1 && errno == ENOSYS) {
                /*
@@ -101,21 +110,34 @@ ext2_loff_t ext2fs_llseek (int fd, ext2_loff_t offset, int origin)
                 * 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 */