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/cvs/gvpe/src/iom.C
Revision: 1.3
Committed: Fri Mar 21 21:21:02 2003 UTC (21 years, 2 months ago) by pcg
Content type: text/plain
Branch: MAIN
Changes since 1.2: +0 -2 lines
Log Message:
*** empty log message ***

File Contents

# Content
1 /*
2 iom.C -- I/O multiplexor
3
4 This program is free software; you can redistribute it and/or modify
5 it under the terms of the GNU General Public License as published by
6 the Free Software Foundation; either version 2 of the License, or
7 (at your option) any later version.
8
9 This program is distributed in the hope that it will be useful,
10 but WITHOUT ANY WARRANTY; without even the implied warranty of
11 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 GNU General Public License for more details.
13
14 You should have received a copy of the GNU General Public License
15 along with this program; if not, write to the Free Software
16 Foundation, Inc. 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
17 */
18
19 #include "config.h"
20
21 #include <sys/time.h>
22
23 #include <algorithm>
24 #include <functional>
25
26 #include "slog.h"
27 #include "iom.h"
28
29 inline bool lowest_first (const time_watcher *a, const time_watcher *b)
30 {
31 return a->at > b->at;
32 }
33
34 tstamp NOW;
35
36 io_manager iom;
37
38 void time_watcher::set (tstamp when)
39 {
40 iom.unreg (this);
41 at = when;
42 iom.reg (this);
43 }
44
45 void io_manager::reg (int fd, short events, io_watcher *w)
46 {
47 pollfd pfd;
48
49 pfd.fd = fd;
50 pfd.events = events;
51
52 pfs.push_back (pfd);
53 iow.push_back (w);
54 }
55
56 void io_manager::unreg (io_watcher *w)
57 {
58 unsigned int sz = iow.size ();
59 unsigned int i = find (iow.begin (), iow.end (), w) - iow.begin ();
60
61 if (i != sz)
62 {
63 if (sz == 1)
64 {
65 pfs.clear ();
66 iow.clear ();
67 }
68 else if (i == sz - 1)
69 {
70 iow.pop_back ();
71 pfs.pop_back ();
72 }
73 else
74 {
75 iow[i] = iow[sz - 1]; iow.pop_back ();
76 pfs[i] = pfs[sz - 1]; pfs.pop_back ();
77 }
78 }
79 }
80
81 void io_manager::reg (time_watcher *w)
82 {
83 tw.push_back (w);
84 push_heap (tw.begin (), tw.end (), lowest_first);
85 }
86
87 void io_manager::unreg (time_watcher *w)
88 {
89 unsigned int sz = tw.size ();
90 unsigned int i = find (tw.begin (), tw.end (), w) - tw.begin ();
91
92 if (i != sz)
93 {
94 if (sz == 1)
95 tw.clear ();
96 else
97 {
98 if (i != sz - 1)
99 tw[i] = tw[sz - 1];
100
101 tw.pop_back ();
102 make_heap (tw.begin (), tw.end (), lowest_first);
103 }
104 }
105 }
106
107 inline void set_now (void)
108 {
109 struct timeval tv;
110
111 gettimeofday (&tv, 0);
112
113 NOW = (tstamp)tv.tv_sec + (tstamp)tv.tv_usec / 1000000;
114 }
115
116 void io_manager::loop ()
117 {
118 set_now ();
119
120 while (!(iow.empty () && tw.empty ()))
121 {
122 int timeout = tw.empty ()
123 ? 3600 * 1000 // wake up at least every hour
124 : (int) ((tw[0]->at - NOW) * 1000);
125
126 printf ("s%d t%d #%d\n", pfs.size (), timeout, tw.size ());
127
128 if (timeout >= 0)
129 {
130 int fds = poll (&pfs[0], pfs.size (), timeout);
131
132 set_now ();
133
134 for (unsigned int i = iow.size (); fds && i--; )
135 if (pfs[i].revents)
136 {
137 --fds;
138 iow[i]->call (pfs[i].revents);
139 }
140 }
141
142 while (!tw.empty () && tw[0]->at <= NOW)
143 {
144 pop_heap (tw.begin (), tw.end (), lowest_first);
145 (*(tw.end () - 1))->trigger ();
146 push_heap (tw.begin (), tw.end (), lowest_first);
147 }
148 }
149 }
150
151 io_manager::io_manager ()
152 {
153 set_now ();
154 }
155
156 io_manager::~io_manager ()
157 {
158 //
159 }
160