| /* |
| * 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% |
| */ |
| |
| #define _LARGEFILE_SOURCE |
| #define _LARGEFILE64_SOURCE |
| |
| #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 */ |
| |
| |