sortix--sortix/libc/stdio/fseeko_unlocked.c

/*
 * Copyright (c) 2011, 2012, 2013, 2014 Jonas 'Sortie' Termansen.
 *
 * Permission to use, copy, modify, and distribute this software for any
 * purpose with or without fee is hereby granted, provided that the above
 * copyright notice and this permission notice appear in all copies.
 *
 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 *
 * stdio/fseeko_unlocked.c
 * Changes the current offset in a FILE.
 */

#include <errno.h>
#include <stdio.h>

int fseeko_unlocked(FILE* fp, off_t offset, int whence)
{
	if ( !fp->seek_func )
		return errno = EBADF, -1;
	if ( fflush_unlocked(fp) != 0 )
		return -1;
	if ( fp->seek_func(fp->user, offset, whence) < 0 )
		return -1;
	fp->flags &= ~_FILE_STATUS_EOF;
	return 0;
}