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Comparing gvpe/src/iom.C (file contents):
Revision 1.2 by pcg, Fri Mar 21 21:17:02 2003 UTC vs.
Revision 1.15 by pcg, Sat Jan 17 15:43:02 2004 UTC

1#include <unistd.h>
2/* 1/*
3 iom.C -- I/O multiplexor 2 iom.C -- generic I/O multiplexor
3 Copyright (C) 2003, 2004 Marc Lehmann <pcg@goof.com>
4 4
5 This program is free software; you can redistribute it and/or modify 5 This program is free software; you can redistribute it and/or modify
6 it under the terms of the GNU General Public License as published by 6 it under the terms of the GNU General Public License as published by
7 the Free Software Foundation; either version 2 of the License, or 7 the Free Software Foundation; either version 2 of the License, or
8 (at your option) any later version. 8 (at your option) any later version.
… …
15 You should have received a copy of the GNU General Public License 15 You should have received a copy of the GNU General Public License
16 along with this program; if not, write to the Free Software 16 along with this program; if not, write to the Free Software
17 Foundation, Inc. 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA 17 Foundation, Inc. 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
18*/ 18*/
19 19
20#include "config.h" 20#include <cstdio>
21#include <cstdlib>
22#include <cerrno>
21 23
22#include <sys/time.h> 24#include <sys/time.h>
23 25
24#include <algorithm> 26#if 1 // older unices need these includes for select(2)
25#include <functional> 27# include <unistd.h>
28# include <sys/types.h>
29#endif
26 30
27#include "slog.h" 31// if the BSDs would at least be marginally POSIX-compatible.. *sigh*
32// until that happens, sys/select.h must come last
33#include <sys/select.h>
28 34
29#include "iom.h" 35#include "iom.h"
30 36
31inline bool lowest_first (const time_watcher *a, const time_watcher *b) 37// TSTAMP_MAX must still fit into a positive struct timeval
32{ 38#define TSTAMP_MAX (double)(1UL<<31)
33 return a->at > b->at; 39
34} 40// this is a dummy time watcher to ensure that the first
41// time watcher is _always_ valid, this gets rid of a lot
42// of null-pointer-checks
43// (must come _before_ iom is being defined)
44static struct tw0 : time_watcher {
45 void cb (time_watcher &w)
46 {
47 // should never get called
48 // reached end-of-time, or tstamp has a bogus definition,
49 // or compiler initilization order broken, or somethine else :)
50 abort ();
51 }
52
53 tw0()
54 : time_watcher (this, &tw0::cb)
55 { }
56} tw0;
35 57
36tstamp NOW; 58tstamp NOW;
37 59static bool iom_valid;
38io_manager iom; 60io_manager iom;
39 61
40void time_watcher::set (tstamp when) 62template<class watcher>
63void io_manager::reg (watcher *w, io_manager_vec<watcher> &queue)
41{ 64{
42 iom.unreg (this); 65 if (!iom_valid)
43 at = when; 66 abort ();
67
68 if (!w->active)
69 {
70 queue.push_back (w);
71 w->active = queue.size ();
72 }
73}
74
75template<class watcher>
76void io_manager::unreg (watcher *w, io_manager_vec<watcher> &queue)
77{
78 if (!iom_valid)
79 return;
80
81 if (w->active)
82 {
83 queue [w->active - 1] = 0;
84 w->active = 0;
85 }
86}
87
88#if IOM_TIME
89void time_watcher::trigger ()
90{
91 call (*this);
92
44 iom.reg (this); 93 iom.reg (this);
45} 94}
46 95
47void io_manager::reg (int fd, short events, io_watcher *w) 96void io_manager::reg (time_watcher *w) { reg (w, tw); }
48{ 97void io_manager::unreg (time_watcher *w) { unreg (w, tw); }
49 pollfd pfd; 98#endif
50 99
51 pfd.fd = fd; 100#if IOM_IO
52 pfd.events = events; 101void io_manager::reg (io_watcher *w) { reg (w, iow); }
53
54 pfs.push_back (pfd);
55 iow.push_back (w);
56}
57
58void io_manager::unreg (io_watcher *w) 102void io_manager::unreg (io_watcher *w) { unreg (w, iow); }
59{ 103#endif
60 unsigned int sz = iow.size ();
61 unsigned int i = find (iow.begin (), iow.end (), w) - iow.begin ();
62 104
63 if (i != sz) 105#if IOM_CHECK
106void io_manager::reg (check_watcher *w) { reg (w, cw); }
107void io_manager::unreg (check_watcher *w) { unreg (w, cw); }
108#endif
109
110#if IOM_IDLE
111void io_manager::reg (idle_watcher *w) { reg (w, iw); }
112void io_manager::unreg (idle_watcher *w) { unreg (w, iw); }
113#endif
114
115#if IOM_TIME
116inline void set_now (void)
117{
118 struct timeval tv;
119
120 gettimeofday (&tv, 0);
121
122 NOW = (tstamp)tv.tv_sec + (tstamp)tv.tv_usec / 1000000;
123#endif
124}
125
126void io_manager::loop ()
127{
128#if IOM_TIME
129 set_now ();
130#endif
131
132 for (;;)
64 { 133 {
65 if (sz == 1) 134 struct timeval *to = 0;
135 struct timeval tval;
136
137#if IOM_IDLE
138 if (iw.size ())
66 { 139 {
67 pfs.clear (); 140 tval.tv_sec = 0;
68 iow.clear (); 141 tval.tv_usec = 0;
69 } 142 to = &tval;
70 else if (i == sz - 1)
71 {
72 iow.pop_back ();
73 pfs.pop_back ();
74 } 143 }
75 else 144 else
145#endif
76 { 146 {
77 iow[i] = iow[sz - 1]; iow.pop_back (); 147#if IOM_TIME
78 pfs[i] = pfs[sz - 1]; pfs.pop_back (); 148 time_watcher *next;
149
150 for (;;)
151 {
152 next = tw[0]; // the first time-watcher must exist at ALL times
153
154 for (int i = tw.size (); i--; )
155 if (!tw[i])
156 tw.erase_unordered (i);
157 else if (tw[i]->at < next->at)
158 next = tw[i];
159
160 if (next->at > NOW)
161 {
162 if (next != tw[0])
163 {
164 double diff = next->at - NOW;
165 tval.tv_sec = (int)diff;
166 tval.tv_usec = (int)((diff - tval.tv_sec) * 1000000);
167 to = &tval;
168 }
169 break;
170 }
171 else
172 {
173 unreg (next);
174 next->call (*next);
175 }
176 }
177#endif
79 } 178 }
179
180#if IOM_CHECK
181 for (int i = cw.size (); i--; )
182 if (!cw[i])
183 cw.erase_unordered (i);
184 else
185 cw[i]->call (*cw[i]);
186#endif
187
188#if IOM_IO
189 fd_set rfd, wfd, efd;
190
191 FD_ZERO (&rfd);
192 FD_ZERO (&wfd);
193
194 int fds = 0;
195
196 for (io_manager_vec<io_watcher>::iterator i = iow.end (); i-- > iow.begin (); )
197 if (*i)
198 {
199 if ((*i)->events & EVENT_READ ) FD_SET ((*i)->fd, &rfd);
200 if ((*i)->events & EVENT_WRITE) FD_SET ((*i)->fd, &wfd);
201
202 if ((*i)->fd >= fds) fds = (*i)->fd + 1;
203 }
204
205 if (!to && !fds) //TODO: also check idle_watchers and check_watchers
206 break; // no events
207
208 fds = select (fds, &rfd, &wfd, &efd, to);
209# if IOM_TIME
210 set_now ();
211# endif
212
213 if (fds > 0)
214 for (int i = iow.size (); i--; )
215 if (!iow[i])
216 iow.erase_unordered (i);
217 else
218 {
219 short revents = iow[i]->events;
220
221 if (!FD_ISSET (iow[i]->fd, &rfd)) revents &= ~EVENT_READ;
222 if (!FD_ISSET (iow[i]->fd, &wfd)) revents &= ~EVENT_WRITE;
223
224 if (revents)
225 iow[i]->call (*iow[i], revents);
226 }
227 else if (fds < 0 && errno != EINTR)
228 {
229 perror ("Error while waiting for I/O or time event");
230 abort ();
231 }
232#if IOM_IDLE
233 else
234 for (int i = iw.size (); i--; )
235 if (!iw[i])
236 iw.erase_unordered (i);
237 else
238 iw[i]->call (*iw[i]);
239#endif
240
241#elif IOM_TIME
242 if (!to)
243 break;
244
245 select (0, 0, 0, 0, &to);
246 set_now ();
247#else
248 break;
249#endif
80 } 250 }
81} 251}
82 252
83void io_manager::reg (time_watcher *w) 253io_manager::io_manager ()
84{ 254{
85 tw.push_back (w); 255 iom_valid = true;
86 push_heap (tw.begin (), tw.end (), lowest_first);
87}
88 256
89void io_manager::unreg (time_watcher *w) 257#if IOM_TIME
90{
91 unsigned int sz = tw.size ();
92 unsigned int i = find (tw.begin (), tw.end (), w) - tw.begin ();
93
94 if (i != sz)
95 {
96 if (sz == 1)
97 tw.clear ();
98 else
99 {
100 if (i != sz - 1)
101 tw[i] = tw[sz - 1];
102
103 tw.pop_back ();
104 make_heap (tw.begin (), tw.end (), lowest_first);
105 }
106 }
107}
108
109inline void set_now (void)
110{
111 struct timeval tv;
112
113 gettimeofday (&tv, 0);
114
115 NOW = (tstamp)tv.tv_sec + (tstamp)tv.tv_usec / 1000000;
116}
117
118void io_manager::loop ()
119{
120 set_now (); 258 set_now ();
121 259
122 while (!(iow.empty () && tw.empty ())) 260 tw0.start (TSTAMP_MAX);
123 { 261 printf ("abort, %f but inly on %f\n", NOW, tw0.at);
124 int timeout = tw.empty () 262#endif
125 ? 3600 * 1000 // wake up at least every hour
126 : (int) ((tw[0]->at - NOW) * 1000);
127
128 printf ("s%d t%d #%d\n", pfs.size (), timeout, tw.size ());
129
130 if (timeout >= 0)
131 {
132 int fds = poll (&pfs[0], pfs.size (), timeout);
133
134 set_now ();
135
136 for (unsigned int i = iow.size (); fds && i--; )
137 if (pfs[i].revents)
138 {
139 --fds;
140 iow[i]->call (pfs[i].revents);
141 }
142 }
143
144 while (!tw.empty () && tw[0]->at <= NOW)
145 {
146 pop_heap (tw.begin (), tw.end (), lowest_first);
147 (*(tw.end () - 1))->trigger ();
148 push_heap (tw.begin (), tw.end (), lowest_first);
149 }
150 }
151}
152
153io_manager::io_manager ()
154{
155 set_now ();
156} 263}
157 264
158io_manager::~io_manager () 265io_manager::~io_manager ()
159{ 266{
160 // 267 iom_valid = false;
161} 268}
162 269

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