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
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
|
/* $Id: sfsync.c,v 1.1.1.1 2004/12/23 04:04:14 ellson Exp $ $Revision: 1.1.1.1 $ */
/* vim:set shiftwidth=4 ts=8: */
/**********************************************************
* This software is part of the graphviz package *
* http://www.graphviz.org/ *
* *
* Copyright (c) 1994-2004 AT&T Corp. *
* and is licensed under the *
* Common Public License, Version 1.0 *
* by AT&T Corp. *
* *
* Information and Software Systems Research *
* AT&T Research, Florham Park NJ *
**********************************************************/
#include "sfhdr.h"
/* Synchronize data in buffers with the file system.
** If f is nil, all streams are sync-ed
**
** Written by Kiem-Phong Vo.
*/
#if __STD_C
static int _sfall(void)
#else
static int _sfall()
#endif
{
reg Sfpool_t *p, *next;
reg Sfio_t *f;
reg int n, rv;
reg int nsync, count, loop;
#define MAXLOOP 3
for (loop = 0; loop < MAXLOOP; ++loop) {
rv = nsync = count = 0;
for (p = &_Sfpool; p; p = next) { /* find the next legitimate pool */
for (next = p->next; next; next = next->next)
if (next->n_sf > 0)
break;
/* walk the streams for _Sfpool only */
for (n = 0; n < ((p == &_Sfpool) ? p->n_sf : 1); ++n) {
count += 1;
f = p->sf[n];
if (f->flags & SF_STRING)
goto did_sync;
if (SFFROZEN(f))
continue;
if ((f->mode & SF_READ) && (f->mode & SF_SYNCED))
goto did_sync;
if ((f->mode & SF_READ) && !(f->bits & SF_MMAP) &&
f->next == f->endb)
goto did_sync;
if ((f->mode & SF_WRITE) && !(f->bits & SF_HOLE) &&
f->next == f->data)
goto did_sync;
if (sfsync(f) < 0)
rv = -1;
did_sync:
nsync += 1;
}
}
if (nsync == count)
break;
}
return rv;
}
#if __STD_C
int sfsync(reg Sfio_t * f)
#else
int sfsync(f)
reg Sfio_t *f; /* stream to be synchronized */
#endif
{
int local, rv, mode;
Sfio_t *origf;
if (!(origf = f))
return _sfall();
SFMTXSTART(origf, -1);
GETLOCAL(origf, local);
if (origf->disc == _Sfudisc) /* throw away ungetc */
(void) sfclose((*_Sfstack) (origf, NIL(Sfio_t *)));
rv = 0;
if ((origf->mode & SF_RDWR) != SFMODE(origf, local)
&& _sfmode(origf, 0, local) < 0) {
rv = -1;
goto done;
}
for (; f; f = f->push) {
if ((f->flags & SF_IOCHECK) && f->disc && f->disc->exceptf)
(void) (*f->disc->exceptf) (f, SF_SYNC, (Void_t *) ((int) 1),
f->disc);
SFLOCK(f, local);
/* pretend that this stream is not on a stack */
mode = f->mode & SF_PUSH;
f->mode &= ~SF_PUSH;
/* these streams do not need synchronization */
if ((f->flags & SF_STRING) || (f->mode & SF_SYNCED))
goto next;
if ((f->mode & SF_WRITE) && (f->next > f->data || (f->bits & SF_HOLE))) { /* sync the buffer, make sure pool don't move */
reg int pool = f->mode & SF_POOL;
f->mode &= ~SF_POOL;
if (f->next > f->data && (SFWRALL(f), SFFLSBUF(f, -1)) < 0)
rv = -1;
if (!SFISNULL(f) && (f->bits & SF_HOLE)) { /* realize a previously created hole of 0's */
if (SFSK(f, (Sfoff_t) (-1), SEEK_CUR, f->disc) >= 0)
(void) SFWR(f, "", 1, f->disc);
f->bits &= ~SF_HOLE;
}
f->mode |= pool;
}
if ((f->mode & SF_READ) && f->extent >= 0 && ((f->bits & SF_MMAP) || f->next < f->endb)) { /* make sure the file pointer is at the right place */
f->here -= (f->endb - f->next);
f->endr = f->endw = f->data;
f->mode = SF_READ | SF_SYNCED | SF_LOCK;
(void) SFSK(f, f->here, SEEK_SET, f->disc);
if ((f->flags & SF_SHARE) && !(f->flags & SF_PUBLIC) &&
!(f->bits & SF_MMAP)) {
f->endb = f->next = f->data;
f->mode &= ~SF_SYNCED;
}
}
next:
f->mode |= mode;
SFOPEN(f, local);
if ((f->flags & SF_IOCHECK) && f->disc && f->disc->exceptf)
(void) (*f->disc->exceptf) (f, SF_SYNC, (Void_t *) ((int) 0),
f->disc);
}
done:
if (!local && f && (f->mode & SF_POOL) && f->pool
&& f != f->pool->sf[0])
SFSYNC(f->pool->sf[0]);
SFMTXRETURN(origf, rv);
}
|
