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Comparing gvpe/src/iom.C (file contents):
Revision 1.4 by pcg, Fri Mar 21 23:17:01 2003 UTC vs.
Revision 1.19 by pcg, Sun Mar 28 01:53:33 2004 UTC

1/* 1/*
2 iom.C -- I/O multiplexor 2 iom.C -- generic I/O multiplexor
3 Copyright (C) 2003, 2004 Marc Lehmann <pcg@goof.com>
3 4
4 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
5 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
6 the Free Software Foundation; either version 2 of the License, or 7 the Free Software Foundation; either version 2 of the License, or
7 (at your option) any later version. 8 (at your option) any later version.
… …
14 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
15 along with this program; if not, write to the Free Software 16 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 Foundation, Inc. 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
17*/ 18*/
18 19
19#include "config.h" 20#include <cstdio>
21#include <cstdlib>
22#include <cerrno>
20 23
21#include <sys/time.h> 24#include <sys/time.h>
22 25
23#include <algorithm> 26#if 1 // older unices need these includes for select (2)
24#include <functional> 27# include <unistd.h>
28# include <sys/types.h>
29#endif
25 30
26#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>
34
27#include "iom.h" 35#include "iom.h"
28 36
29inline bool lowest_first (const time_watcher *a, const time_watcher *b) 37// TSTAMP_MAX must still fit into a positive struct timeval
30{ 38#define TSTAMP_MAX (double)(1UL<<31)
31 return a->at > b->at; 39
32} 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 {
46 void cb (time_watcher &w)
47 {
48 // should never get called
49 // reached end-of-time, or tstamp has a bogus definition,
50 // or compiler initilization order broken, or somethine else :)
51 abort ();
52 }
53
54 tw0 ()
55 : time_watcher (this, &tw0::cb)
56 { }}
57tw0;
33 58
34tstamp NOW; 59tstamp NOW;
35 60static bool iom_valid;
36io_manager iom; 61io_manager iom;
37 62
38void time_watcher::set (tstamp when) 63template<class watcher>
64void io_manager::reg (watcher *w, io_manager_vec<watcher> &queue)
39{ 65{
40 iom.unreg (this); 66 if (!iom_valid)
41 at = when; 67 abort ();
68
69 if (!w->active)
70 {
71#if IOM_CHECK
72 queue.activity = true;
73#endif
74 queue.push_back (w);
75 w->active = queue.size ();
76 }
77}
78
79template<class watcher>
80void io_manager::unreg (watcher *w, io_manager_vec<watcher> &queue)
81{
82 if (!iom_valid)
83 return;
84
85 if (w->active)
86 {
87 queue [w->active - 1] = 0;
88 w->active = 0;
89 }
90}
91
92#if IOM_TIME
93void time_watcher::trigger ()
94{
95 call (*this);
96
42 iom.reg (this); 97 iom.reg (this);
43} 98}
44 99
45void time_watcher::trigger () 100void io_manager::reg (time_watcher *w) { reg (w, tw); }
46{ 101void io_manager::unreg (time_watcher *w) { unreg (w, tw); }
47 iom.unreg (this); 102#endif
48 call (at);
49 iom.reg (this);
50}
51 103
52void time_watcher::start () 104#if IOM_IO
53{ 105void io_manager::reg (io_watcher *w) { reg (w, iow); }
54 iom.unreg (this);
55 iom.reg (this);
56}
57
58void io_manager::reg (int fd, short events, io_watcher *w)
59{
60 pollfd pfd;
61
62 pfd.fd = fd;
63 pfd.events = events;
64
65 pfs.push_back (pfd);
66 iow.push_back (w);
67}
68
69void io_manager::unreg (io_watcher *w) 106void io_manager::unreg (io_watcher *w) { unreg (w, iow); }
70{ 107#endif
71 unsigned int sz = iow.size ();
72 unsigned int i = find (iow.begin (), iow.end (), w) - iow.begin ();
73 108
74 if (i != sz) 109#if IOM_CHECK
110void io_manager::reg (check_watcher *w) { reg (w, cw); }
111void io_manager::unreg (check_watcher *w) { unreg (w, cw); }
112#endif
113
114#if IOM_IDLE
115void io_manager::reg (idle_watcher *w) { reg (w, iw); }
116void io_manager::unreg (idle_watcher *w) { unreg (w, iw); }
117#endif
118
119#if IOM_TIME
120inline void set_now (void)
121{
122 struct timeval tv;
123
124 gettimeofday (&tv, 0);
125
126 NOW = (tstamp)tv.tv_sec + (tstamp)tv.tv_usec / 1000000;
127#endif
128}
129
130void io_manager::loop ()
131{
132#if IOM_TIME
133 set_now ();
134#endif
135
136 for (;;)
75 { 137 {
76 if (sz == 1) 138 struct timeval *to = 0;
77 { 139 struct timeval tval;
78 pfs.clear (); 140
79 iow.clear (); 141#if IOM_IDLE
142 if (iw.size ())
80 } 143 {
81 else if (i == sz - 1) 144 tval.tv_sec = 0;
82 { 145 tval.tv_usec = 0;
83 iow.pop_back (); 146 to = &tval;
84 pfs.pop_back ();
85 } 147 }
86 else 148 else
149#endif
150
151 {
152#if IOM_TIME
153 time_watcher *next;
154
155 for (;;)
156 {
157 next = tw[0]; // the first time-watcher must exist at ALL times
158
159 for (int i = tw.size (); i--; )
160 if (!tw[i])
161 tw.erase_unordered (i);
162 else if (tw[i]->at < next->at)
163 next = tw[i];
164
165 if (next->at > NOW)
166 {
167 if (next != tw[0])
168 {
169 double diff = next->at - NOW;
170 tval.tv_sec = (int)diff;
171 tval.tv_usec = (int) ((diff - tval.tv_sec) * 1000000);
172 to = &tval;
173 }
174 break;
175 }
176 else
177 {
178 unreg (next);
179 next->call (*next);
180 }
181 }
182#endif
183
184 }
185
186#if IOM_CHECK
187 tw.activity = false;
188
189 for (int i = cw.size (); i--; )
190 if (!cw[i])
191 cw.erase_unordered (i);
192 else
193 cw[i]->call (*cw[i]);
194
195 if (tw.activity)
196 {
197 tval.tv_sec = 0;
198 tval.tv_usec = 0;
199 to = &tval;
200 }
201#endif
202
203#if IOM_IO
204 fd_set rfd, wfd;
205
206 FD_ZERO (&rfd);
207 FD_ZERO (&wfd);
208
209 int fds = 0;
210
211 for (io_manager_vec<io_watcher>::iterator i = iow.end (); i-- > iow.begin (); )
212 if (*i)
87 { 213 {
88 iow[i] = iow[sz - 1]; iow.pop_back (); 214 if ((*i)->events & EVENT_READ ) FD_SET ((*i)->fd, &rfd);
89 pfs[i] = pfs[sz - 1]; pfs.pop_back (); 215 if ((*i)->events & EVENT_WRITE) FD_SET ((*i)->fd, &wfd);
216
217 if ((*i)->fd >= fds) fds = (*i)->fd + 1;
90 } 218 }
91 }
92}
93 219
94void io_manager::reg (time_watcher *w) 220 if (!to && !fds) //TODO: also check idle_watchers and check_watchers
95{ 221 break; // no events
96 tw.push_back (w);
97 push_heap (tw.begin (), tw.end (), lowest_first);
98}
99 222
100void io_manager::unreg (time_watcher *w) 223 fds = select (fds, &rfd, &wfd, NULL, to);
101{ 224# if IOM_TIME
102 unsigned int sz = tw.size (); 225 set_now ();
103 unsigned int i = find (tw.begin (), tw.end (), w) - tw.begin (); 226# endif
104 227
105 if (i != sz) 228 if (fds > 0)
229 for (int i = iow.size (); i--; )
230 if (!iow[i])
231 iow.erase_unordered (i);
232 else
233 {
234 short revents = iow[i]->events;
235
236 if (!FD_ISSET (iow[i]->fd, &rfd)) revents &= ~EVENT_READ;
237 if (!FD_ISSET (iow[i]->fd, &wfd)) revents &= ~EVENT_WRITE;
238
239 if (revents)
240 iow[i]->call (*iow[i], revents);
241 }
242 else if (fds < 0 && errno != EINTR)
243 {
244 perror ("Error while waiting for I/O or time event");
245 abort ();
246 }
247#if IOM_IDLE
248 else
249 for (int i = iw.size (); i--; )
250 if (!iw[i])
251 iw.erase_unordered (i);
252 else
253 iw[i]->call (*iw[i]);
254#endif
255
256#elif IOM_TIME
257 if (!to)
258 break;
259
260 select (0, 0, 0, 0, &to);
261 set_now ();
262#else
263 break;
264#endif
265
106 { 266 }
107 if (i != sz - 1)
108 tw[i] = tw[sz - 1];
109
110 tw.pop_back ();
111 make_heap (tw.begin (), tw.end (), lowest_first);
112 }
113} 267}
114 268
115inline void set_now (void) 269io_manager::io_manager ()
116{ 270{
117 struct timeval tv; 271 iom_valid = true;
118 272
119 gettimeofday (&tv, 0); 273#if IOM_TIME
120
121 NOW = (tstamp)tv.tv_sec + (tstamp)tv.tv_usec / 1000000;
122}
123
124void io_manager::loop ()
125{
126 set_now (); 274 set_now ();
127 275
128 for (;;) 276 tw0.start (TSTAMP_MAX);
129 { 277#endif
130 while (tw[0]->at <= NOW)
131 {
132 pop_heap (tw.begin (), tw.end (), lowest_first);
133 time_watcher *w = *(tw.end () - 1);
134
135 if (w->at >= 0)
136 {
137 w->call (w->at);
138 push_heap (tw.begin (), tw.end (), lowest_first);
139 }
140 else
141 tw.pop_back ();
142 }
143
144 int timeout = (int) ((tw[0]->at - NOW) * 1000);
145
146 int fds = poll (&pfs[0], pfs.size (), timeout);
147
148 set_now ();
149
150 for (unsigned int i = iow.size (); fds > 0 && i--; )
151 if (pfs[i].revents)
152 {
153 --fds;
154 iow[i]->call (pfs[i].revents);
155 }
156 }
157}
158
159void io_manager::idle_cb (tstamp &ts)
160{
161 ts = NOW + 86400; // wake up every day, for no good reason
162}
163
164io_manager::io_manager ()
165{
166 set_now ();
167 idle = new time_watcher (this, &io_manager::idle_cb);
168 idle->start (0);
169} 278}
170 279
171io_manager::~io_manager () 280io_manager::~io_manager ()
172{ 281{
173 // 282 iom_valid = false;
174} 283}
175 284

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