1 /*
2 Copyright (c) 2010 - 2012, Intel Corporation. All rights reserved.<BR>
3 This program and the accompanying materials are licensed and made available
4 under the terms and conditions of the BSD License that accompanies this
5 distribution. The full text of the license may be found at
6 http://opensource.org/licenses/bsd-license.
7
8 THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
9 WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
10
11 * Copyright (c) 1990, 1993
12 * The Regents of the University of California. All rights reserved.
13 *
14 * This code is derived from software contributed to Berkeley by
15 * Chris Torek.
16 *
17 * Redistribution and use in source and binary forms, with or without
18 * modification, are permitted provided that the following conditions
19 * are met:
20 * 1. Redistributions of source code must retain the above copyright
21 * notice, this list of conditions and the following disclaimer.
22 * 2. Redistributions in binary form must reproduce the above copyright
23 * notice, this list of conditions and the following disclaimer in the
24 * documentation and/or other materials provided with the distribution.
25 * 3. Neither the name of the University nor the names of its contributors
26 * may be used to endorse or promote products derived from this software
27 * without specific prior written permission.
28 *
29 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
30 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
31 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
32 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
33 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
34 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
35 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
36 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
37 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
38 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
39 * SUCH DAMAGE.
40
41 NetBSD: refill.c,v 1.13 2003/08/07 16:43:30 agc Exp
42 refill.c 8.1 (Berkeley) 6/4/93
43 */
44 #include <LibConfig.h>
45 #include <sys/EfiCdefs.h>
46
47 #include <assert.h>
48 #include <errno.h>
49 #include <stdio.h>
50 #include <stdlib.h>
51 #include "reentrant.h"
52 #include "local.h"
53
54 #ifdef _REENTRANT
55 extern rwlock_t __sfp_lock;
56 #endif
57
58 static int lflush(FILE *);
59
60 static int
lflush(FILE * fp)61 lflush(FILE *fp)
62 {
63
64 _DIAGASSERT(fp != NULL);
65 if(fp == NULL) {
66 errno = EINVAL;
67 return (EOF);
68 }
69
70 if ((fp->_flags & (__SLBF|__SWR)) == (__SLBF|__SWR))
71 return (__sflush(fp));
72 return (0);
73 }
74
75 /*
76 * Refill a stdio buffer.
77 * Return EOF on eof or error, 0 otherwise.
78 */
79 int
__srefill(FILE * fp)80 __srefill(FILE *fp)
81 {
82
83 _DIAGASSERT(fp != NULL);
84 if(fp == NULL) {
85 errno = EINVAL;
86 return (EOF);
87 }
88
89 /* make sure stdio is set up */
90 if (!__sdidinit)
91 __sinit();
92
93 fp->_r = 0; /* largely a convenience for callers */
94
95 /* SysV does not make this test; take it out for compatibility */
96 if (fp->_flags & __SEOF) {
97 return (EOF);
98 }
99
100 /* if not already reading, have to be reading and writing */
101 if ((fp->_flags & __SRD) == 0) {
102 if ((fp->_flags & __SRW) == 0) {
103 errno = EBADF;
104 fp->_flags |= __SERR; //<dvm> Allows differentiation between errors and EOF
105 return (EOF);
106 }
107 /* switch to reading */
108 if (fp->_flags & __SWR) {
109 if (__sflush(fp)) {
110 return (EOF);
111 }
112 fp->_flags &= ~__SWR;
113 fp->_w = 0;
114 fp->_lbfsize = 0;
115 }
116 fp->_flags |= __SRD;
117 } else {
118 /*
119 * We were reading. If there is an ungetc buffer,
120 * we must have been reading from that. Drop it,
121 * restoring the previous buffer (if any). If there
122 * is anything in that buffer, return.
123 */
124 if (HASUB(fp)) {
125 FREEUB(fp);
126 if ((fp->_r = fp->_ur) != 0) {
127 fp->_p = fp->_up;
128 return (0);
129 }
130 }
131 }
132
133 if (fp->_bf._base == NULL)
134 __smakebuf(fp);
135
136 /*
137 * Before reading from a line buffered or unbuffered file,
138 * flush all line buffered output files, per the ANSI C
139 * standard.
140 */
141 if (fp->_flags & (__SLBF|__SNBF)) {
142 rwlock_rdlock(&__sfp_lock);
143 (void) _fwalk(lflush);
144 rwlock_unlock(&__sfp_lock);
145 }
146 fp->_p = fp->_bf._base;
147 fp->_r = (*fp->_read)(fp->_cookie, (char *)fp->_p, fp->_bf._size);
148 fp->_flags &= ~__SMOD; /* buffer contents are again pristine */
149 if (fp->_r <= 0) {
150 if (fp->_r == 0)
151 fp->_flags |= __SEOF;
152 else {
153 fp->_r = 0;
154 fp->_flags |= __SERR;
155 }
156 return (EOF);
157 }
158 return (0);
159 }
160