refill.c - vx32 - Local 9vx git repository for patches.
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---
refill.c (3882B)
---
1 /*-
2 * Copyright (c) 1990, 1993
3 * The Regents of the University of California. All rights reserved.
4 *
5 * This code is derived from software contributed to Berkeley by
6 * Chris Torek.
7 *
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
10 * are met:
11 * 1. Redistributions of source code must retain the above copyright
12 * notice, this list of conditions and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 * notice, this list of conditions and the following disclaimer in the
15 * documentation and/or other materials provided with the distribution.
16 * 3. All advertising materials mentioning features or use of this software
17 * must display the following acknowledgement:
18 * This product includes software developed by the University of
19 * California, Berkeley and its contributors.
20 * 4. Neither the name of the University nor the names of its contributors
21 * may be used to endorse or promote products derived from this software
22 * without specific prior written permission.
23 *
24 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
25 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
26 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
27 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
28 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
29 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
30 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
31 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
32 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
33 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
34 * SUCH DAMAGE.
35 */
36
37 #if defined(LIBC_SCCS) && !defined(lint)
38 static char rcsid[] = "$OpenBSD: refill.c,v 1.3 1996/08/19 08:33:00 tholo Exp $";
39 #endif /* LIBC_SCCS and not lint */
40
41 #include <errno.h>
42 #include <stdio.h>
43 #include <stdlib.h>
44 #include "local.h"
45
46 static int
47 lflush(fp)
48 FILE *fp;
49 {
50
51 if ((fp->_flags & (__SLBF|__SWR)) == (__SLBF|__SWR))
52 return (__sflush(fp));
53 return (0);
54 }
55
56 /*
57 * Refill a stdio buffer.
58 * Return EOF on eof or error, 0 otherwise.
59 */
60 int
61 __srefill(fp)
62 register FILE *fp;
63 {
64
65 /* make sure stdio is set up */
66 if (!__sdidinit)
67 __sinit();
68
69 fp->_r = 0; /* largely a convenience for callers */
70
71 /* SysV does not make this test; take it out for compatibility */
72 if (fp->_flags & __SEOF)
73 return (EOF);
74
75 /* if not already reading, have to be reading and writing */
76 if ((fp->_flags & __SRD) == 0) {
77 if ((fp->_flags & __SRW) == 0) {
78 errno = EBADF;
79 return (EOF);
80 }
81 /* switch to reading */
82 if (fp->_flags & __SWR) {
83 if (__sflush(fp))
84 return (EOF);
85 fp->_flags &= ~__SWR;
86 fp->_w = 0;
87 fp->_lbfsize = 0;
88 }
89 fp->_flags |= __SRD;
90 } else {
91 /*
92 * We were reading. If there is an ungetc buffer,
93 * we must have been reading from that. Drop it,
94 * restoring the previous buffer (if any). If there
95 * is anything in that buffer, return.
96 */
97 if (HASUB(fp)) {
98 FREEUB(fp);
99 if ((fp->_r = fp->_ur) != 0) {
100 fp->_p = fp->_up;
101 return (0);
102 }
103 }
104 }
105
106 if (fp->_bf._base == NULL)
107 __smakebuf(fp);
108
109 /*
110 * Before reading from a line buffered or unbuffered file,
111 * flush all line buffered output files, per the ANSI C
112 * standard.
113 */
114 if (fp->_flags & (__SLBF|__SNBF))
115 (void) _fwalk(lflush);
116 fp->_p = fp->_bf._base;
117 fp->_r = (*fp->_read)(fp->_cookie, (char *)fp->_p, fp->_bf._size);
118 fp->_flags &= ~__SMOD; /* buffer contents are again pristine */
119 if (fp->_r <= 0) {
120 if (fp->_r == 0)
121 fp->_flags |= __SEOF;
122 else {
123 fp->_r = 0;
124 fp->_flags |= __SERR;
125 }
126 return (EOF);
127 }
128 return (0);
129 }