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Revision: 1.6
Committed: Fri Mar 28 04:05:10 2003 UTC (21 years, 2 months ago) by pcg
Content type: text/plain
Branch: MAIN
Changes since 1.5: +25 -10 lines
Log Message:
*** empty log message ***

File Contents

# User Rev Content
1 pcg 1.1 /*
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 pcg 1.2 tstamp NOW;
35 pcg 1.1
36     io_manager iom;
37    
38 pcg 1.2 void time_watcher::set (tstamp when)
39 pcg 1.1 {
40     at = when;
41 pcg 1.6
42     if (registered)
43     iom.reschedule_time_watchers ();
44     else
45     iom.reg (this);
46 pcg 1.1 }
47    
48 pcg 1.4 void time_watcher::trigger ()
49     {
50     call (at);
51 pcg 1.6
52     if (registered)
53     iom.reschedule_time_watchers ();
54     else
55     iom.reg (this);
56 pcg 1.4 }
57    
58     void time_watcher::start ()
59     {
60 pcg 1.6 if (!registered)
61     iom.reg (this);
62 pcg 1.4 }
63    
64 pcg 1.1 void io_manager::reg (int fd, short events, io_watcher *w)
65     {
66     pollfd pfd;
67    
68     pfd.fd = fd;
69     pfd.events = events;
70    
71     pfs.push_back (pfd);
72     iow.push_back (w);
73     }
74    
75 pcg 1.5 void io_manager::unreg (const io_watcher *w)
76 pcg 1.1 {
77     unsigned int sz = iow.size ();
78     unsigned int i = find (iow.begin (), iow.end (), w) - iow.begin ();
79    
80     if (i != sz)
81     {
82     if (sz == 1)
83     {
84     pfs.clear ();
85     iow.clear ();
86     }
87     else if (i == sz - 1)
88     {
89     iow.pop_back ();
90     pfs.pop_back ();
91     }
92     else
93     {
94     iow[i] = iow[sz - 1]; iow.pop_back ();
95     pfs[i] = pfs[sz - 1]; pfs.pop_back ();
96     }
97     }
98     }
99    
100 pcg 1.6 void io_manager::reschedule_time_watchers ()
101     {
102     make_heap (tw.begin (), tw.end (), lowest_first);
103     }
104    
105 pcg 1.1 void io_manager::reg (time_watcher *w)
106     {
107 pcg 1.6 if (w->registered)
108     slog (L_CRIT, "FATAL: io_manager::reg(time_watcher) called on already-registered watcher");
109    
110 pcg 1.1 tw.push_back (w);
111     push_heap (tw.begin (), tw.end (), lowest_first);
112     }
113    
114 pcg 1.5 void io_manager::unreg (const time_watcher *w)
115 pcg 1.1 {
116     unsigned int sz = tw.size ();
117     unsigned int i = find (tw.begin (), tw.end (), w) - tw.begin ();
118    
119     if (i != sz)
120     {
121 pcg 1.4 if (i != sz - 1)
122     tw[i] = tw[sz - 1];
123 pcg 1.1
124 pcg 1.4 tw.pop_back ();
125 pcg 1.6 reschedule_time_watchers ();
126 pcg 1.1 }
127     }
128    
129     inline void set_now (void)
130     {
131     struct timeval tv;
132    
133     gettimeofday (&tv, 0);
134    
135 pcg 1.2 NOW = (tstamp)tv.tv_sec + (tstamp)tv.tv_usec / 1000000;
136 pcg 1.1 }
137    
138     void io_manager::loop ()
139     {
140     set_now ();
141    
142 pcg 1.4 for (;;)
143 pcg 1.1 {
144 pcg 1.4 while (tw[0]->at <= NOW)
145     {
146     pop_heap (tw.begin (), tw.end (), lowest_first);
147     time_watcher *w = *(tw.end () - 1);
148 pcg 1.6 tw.pop_back ();
149 pcg 1.1
150 pcg 1.4 if (w->at >= 0)
151     {
152     w->call (w->at);
153 pcg 1.6
154     if (!w->registered)
155     reg (w);
156 pcg 1.4 }
157     }
158 pcg 1.1
159 pcg 1.4 int timeout = (int) ((tw[0]->at - NOW) * 1000);
160 pcg 1.1
161 pcg 1.4 int fds = poll (&pfs[0], pfs.size (), timeout);
162 pcg 1.1
163 pcg 1.4 set_now ();
164 pcg 1.1
165 pcg 1.4 for (unsigned int i = iow.size (); fds > 0 && i--; )
166     if (pfs[i].revents)
167     {
168     --fds;
169     iow[i]->call (pfs[i].revents);
170     }
171 pcg 1.1 }
172     }
173    
174 pcg 1.4 void io_manager::idle_cb (tstamp &ts)
175     {
176     ts = NOW + 86400; // wake up every day, for no good reason
177     }
178    
179 pcg 1.1 io_manager::io_manager ()
180     {
181     set_now ();
182 pcg 1.4 idle = new time_watcher (this, &io_manager::idle_cb);
183     idle->start (0);
184 pcg 1.1 }
185    
186     io_manager::~io_manager ()
187     {
188     //
189     }
190