GCC Code Coverage Report
Directory: ./ Exec Total Coverage
File: lib/libc/stdio/refill.c Lines: 0 42 0.0 %
Date: 2017-11-13 Branches: 0 30 0.0 %

Line Branch Exec Source
1
/*	$OpenBSD: refill.c,v 1.11 2009/11/09 00:18:27 kurt Exp $ */
2
/*-
3
 * Copyright (c) 1990, 1993
4
 *	The Regents of the University of California.  All rights reserved.
5
 *
6
 * This code is derived from software contributed to Berkeley by
7
 * Chris Torek.
8
 *
9
 * Redistribution and use in source and binary forms, with or without
10
 * modification, are permitted provided that the following conditions
11
 * are met:
12
 * 1. Redistributions of source code must retain the above copyright
13
 *    notice, this list of conditions and the following disclaimer.
14
 * 2. Redistributions in binary form must reproduce the above copyright
15
 *    notice, this list of conditions and the following disclaimer in the
16
 *    documentation and/or other materials provided with the distribution.
17
 * 3. Neither the name of the University nor the names of its contributors
18
 *    may be used to endorse or promote products derived from this software
19
 *    without specific prior written permission.
20
 *
21
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
22
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
25
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31
 * SUCH DAMAGE.
32
 */
33
34
#include <errno.h>
35
#include <stdio.h>
36
#include <stdlib.h>
37
#include "local.h"
38
39
static int
40
lflush(FILE *fp)
41
{
42
	if ((fp->_flags & (__SLBF|__SWR)) == (__SLBF|__SWR))
43
		return (__sflush_locked(fp));	/* ignored... */
44
	return (0);
45
}
46
47
/*
48
 * Refill a stdio buffer.
49
 * Return EOF on eof or error, 0 otherwise.
50
 */
51
int
52
__srefill(FILE *fp)
53
{
54
55
	/* make sure stdio is set up */
56
	if (!__sdidinit)
57
		__sinit();
58
59
	fp->_r = 0;		/* largely a convenience for callers */
60
61
	/* SysV does not make this test; take it out for compatibility */
62
	if (fp->_flags & __SEOF)
63
		return (EOF);
64
65
	/* if not already reading, have to be reading and writing */
66
	if ((fp->_flags & __SRD) == 0) {
67
		if ((fp->_flags & __SRW) == 0) {
68
			errno = EBADF;
69
			fp->_flags |= __SERR;
70
			return (EOF);
71
		}
72
		/* switch to reading */
73
		if (fp->_flags & __SWR) {
74
			if (__sflush(fp))
75
				return (EOF);
76
			fp->_flags &= ~__SWR;
77
			fp->_w = 0;
78
			fp->_lbfsize = 0;
79
		}
80
		fp->_flags |= __SRD;
81
	} else {
82
		/*
83
		 * We were reading.  If there is an ungetc buffer,
84
		 * we must have been reading from that.  Drop it,
85
		 * restoring the previous buffer (if any).  If there
86
		 * is anything in that buffer, return.
87
		 */
88
		if (HASUB(fp)) {
89
			FREEUB(fp);
90
			if ((fp->_r = fp->_ur) != 0) {
91
				fp->_p = fp->_up;
92
				return (0);
93
			}
94
		}
95
	}
96
97
	if (fp->_bf._base == NULL)
98
		__smakebuf(fp);
99
100
	/*
101
	 * Before reading from a line buffered or unbuffered file,
102
	 * flush all line buffered output files, per the ANSI C
103
	 * standard.
104
	 */
105
	if (fp->_flags & (__SLBF|__SNBF)) {
106
		/* Ignore this file in _fwalk to avoid potential deadlock. */
107
		fp->_flags |= __SIGN;
108
		(void) _fwalk(lflush);
109
		fp->_flags &= ~__SIGN;
110
111
		/* Now flush this file without locking it. */
112
		if ((fp->_flags & (__SLBF|__SWR)) == (__SLBF|__SWR))
113
			__sflush(fp);
114
	}
115
	fp->_p = fp->_bf._base;
116
	fp->_r = (*fp->_read)(fp->_cookie, (char *)fp->_p, fp->_bf._size);
117
	fp->_flags &= ~__SMOD;	/* buffer contents are again pristine */
118
	if (fp->_r <= 0) {
119
		if (fp->_r == 0)
120
			fp->_flags |= __SEOF;
121
		else {
122
			fp->_r = 0;
123
			fp->_flags |= __SERR;
124
		}
125
		return (EOF);
126
	}
127
	return (0);
128
}