minix/lib/libc/sys-minix/lseek.c
Thomas Veerman c1a31d53d9 stat.h: remove some big_ types
Change-Id: I84017db3d54edfb823cc52e02d0b07fccb003988
2014-02-18 11:25:01 +01:00

54 lines
1 KiB
C

#include <sys/cdefs.h>
#include "namespace.h"
#include <lib.h>
#include <minix/u64.h>
#include <errno.h>
#include <unistd.h>
#ifdef __weak_alias
__weak_alias(lseek, _lseek)
#endif
i32_t __lseek_321(int fd, i32_t offset, int whence);
i32_t __lseek_321(int fd, i32_t offset, int whence)
{
message m;
m.m2_i1 = fd;
m.m2_l1 = offset;
m.m2_i2 = whence;
if (_syscall(VFS_PROC_NR, LSEEK_321, &m) < 0) return(-1);
return( (i32_t) m.m2_l1);
}
off_t
lseek(int fd, off_t offset, int whence)
{
message m;
int orig_errno;
m.m2_i1 = fd;
m.m2_l1 = ex64lo(offset);
m.m2_l2 = ex64hi(offset);
m.m2_i2 = whence;
orig_errno = errno;
if (_syscall(VFS_PROC_NR, LSEEK, &m) < 0) {
if (errno == ENOSYS) {
/* Old VFS, no support for new lseek */
if (offset >= INT_MIN && offset <= INT_MAX) {
/* offset fits in old range, retry */
errno = orig_errno;
return (off_t) __lseek_321(fd, (i32_t) offset, whence);
}
/* Not going to fit */
errno = EOVERFLOW;
}
return( (off_t) -1);
}
return( (off_t) make64(m.m2_l1, m.m2_l2));
}