GCC Code Coverage Report
Directory: ./ Exec Total Coverage
File: lib/libc/stdio/ftell.c Lines: 13 23 56.5 %
Date: 2017-11-13 Branches: 7 20 35.0 %

Line Branch Exec Source
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/*	$OpenBSD: ftell.c,v 1.11 2015/08/31 02:53:57 guenther Exp $ */
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/*-
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 * Copyright (c) 1990, 1993
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 *	The Regents of the University of California.  All rights reserved.
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 *
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 * This code is derived from software contributed to Berkeley by
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 * Chris Torek.
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 *
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 * Redistribution and use in source and binary forms, with or without
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 * modification, are permitted provided that the following conditions
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 * are met:
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 * 1. Redistributions of source code must retain the above copyright
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 *    notice, this list of conditions and the following disclaimer.
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 * 2. Redistributions in binary form must reproduce the above copyright
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 *    notice, this list of conditions and the following disclaimer in the
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 *    documentation and/or other materials provided with the distribution.
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 * 3. Neither the name of the University nor the names of its contributors
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 *    may be used to endorse or promote products derived from this software
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 *    without specific prior written permission.
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 *
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 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
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 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
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 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
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 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
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 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
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 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
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 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
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 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
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 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
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 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
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 * SUCH DAMAGE.
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 */
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#include <stdio.h>
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#include <errno.h>
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#include <limits.h>
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#include "local.h"
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/*
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 * ftello: return current offset.
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 */
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off_t
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ftello(FILE *fp)
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{
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	fpos_t pos;
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2104
	if (fp->_seek == NULL) {
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		errno = ESPIPE;			/* historic practice */
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		pos = -1;
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		goto out;
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	}
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	/*
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	 * Find offset of underlying I/O object, then
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	 * adjust for buffered bytes.
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	 */
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1052
	FLOCKFILE(fp);
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	__sflush(fp);		/* may adjust seek offset on append stream */
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	if (fp->_flags & __SOFF)
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		pos = fp->_offset;
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	else {
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		pos = (*fp->_seek)(fp->_cookie, (fpos_t)0, SEEK_CUR);
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		if (pos == -1)
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			goto out;
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	}
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	if (fp->_flags & __SRD) {
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		/*
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		 * Reading.  Any unread characters (including
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		 * those from ungetc) cause the position to be
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		 * smaller than that in the underlying object.
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		 */
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		pos -= fp->_r;
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		if (HASUB(fp))
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			pos -= fp->_ur;
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	} else if (fp->_flags & __SWR && fp->_p != NULL) {
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		/*
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		 * Writing.  Any buffered characters cause the
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		 * position to be greater than that in the
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		 * underlying object.
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		 */
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		pos += fp->_p - fp->_bf._base;
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	}
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out:	FUNLOCKFILE(fp);
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	return (pos);
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}
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DEF_WEAK(ftello);
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long
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ftell(FILE *fp)
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{
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2104
	off_t offset = ftello(fp);
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1052
	if (offset > LONG_MAX) {
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		errno = EOVERFLOW;
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		return (-1);
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	}
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	return ((long)offset);
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1052
}
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DEF_STRONG(ftell);