1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
|
/* No user fns here. Pesch 15apr92. */
/*
* Copyright (c) 1990 The Regents of the University of California.
* All rights reserved.
*
* Redistribution and use in source and binary forms are permitted
* provided that the above copyright notice and this paragraph are
* duplicated in all such forms and that any documentation,
* advertising materials, and other materials related to such
* distribution and use acknowledge that the software was developed
* by the University of California, Berkeley. The name of the
* University may not be used to endorse or promote products derived
* from this software without specific prior written permission.
* THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
* WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
*/
#include <stdio.h>
#include "local.h"
#include <stdlib.h>
static int
lflush (fp)
FILE *fp;
{
if ((fp->_flags & (__SLBF | __SWR)) == __SLBF | __SWR)
return fflush (fp);
return 0;
}
/*
* Refill a stdio buffer.
* Return EOF on eof or error, 0 otherwise.
*/
int
_DEFUN (__srefill, (fp),
register FILE * fp)
{
/* make sure stdio is set up */
CHECK_INIT (fp);
fp->_r = 0; /* largely a convenience for callers */
/* SysV does not make this test; take it out for compatibility */
if (fp->_flags & __SEOF)
return EOF;
/* if not already reading, have to be reading and writing */
if ((fp->_flags & __SRD) == 0)
{
if ((fp->_flags & __SRW) == 0)
return EOF;
/* switch to reading */
if (fp->_flags & __SWR)
{
if (fflush (fp))
return EOF;
fp->_flags &= ~__SWR;
fp->_w = 0;
fp->_lbfsize = 0;
}
fp->_flags |= __SRD;
}
else
{
/*
* We were reading. If there is an ungetc buffer,
* we must have been reading from that. Drop it,
* restoring the previous buffer (if any). If there
* is anything in that buffer, return.
*/
if (HASUB (fp))
{
FREEUB (fp);
if ((fp->_r = fp->_ur) != 0)
{
fp->_p = fp->_up;
return 0;
}
}
}
if (fp->_bf._base == NULL)
__smakebuf (fp);
/*
* Before reading from a line buffered or unbuffered file,
* flush all line buffered output files, per the ANSI C
* standard.
*/
if (fp->_flags & (__SLBF | __SNBF))
(void) _fwalk (fp->_data, lflush);
fp->_p = fp->_bf._base;
fp->_r = (*fp->_read) (fp->_cookie, (char *) fp->_p, fp->_bf._size);
fp->_flags &= ~__SMOD; /* buffer contents are again pristine */
if (fp->_r <= 0)
{
if (fp->_r == 0)
fp->_flags |= __SEOF;
else
{
fp->_r = 0;
fp->_flags |= __SERR;
}
return EOF;
}
return 0;
}
|
