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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 1.13 by pcg, Sat Jan 17 01:18:36 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
24#include <sys/select.h>
21#include <sys/time.h> 25#include <sys/time.h>
22 26
23#include <algorithm>
24#include <functional>
25
26#include "slog.h"
27#include "iom.h" 27#include "iom.h"
28 28
29inline bool lowest_first (const time_watcher *a, const time_watcher *b) 29// TSTAMP_MAX must still fit into a positive struct timeval
30{ 30#define TSTAMP_MAX (double)(1UL<<31)
31 return a->at > b->at;
32}
33 31
34tstamp NOW; 32tstamp NOW;
35 33static bool iom_valid;
36io_manager iom; 34io_manager iom;
37 35
38void time_watcher::set (tstamp when) 36template<class watcher>
37void io_manager::reg (watcher *w, io_manager_vec<watcher> &queue)
39{ 38{
40 iom.unreg (this); 39 if (!iom_valid)
41 at = when; 40 abort ();
41
42 if (!w->active)
43 {
44 queue.push_back (w);
45 w->active = queue.size ();
46 }
47}
48
49template<class watcher>
50void io_manager::unreg (watcher *w, io_manager_vec<watcher> &queue)
51{
52 if (!iom_valid)
53 return;
54
55 if (w->active)
56 {
57 queue [w->active - 1] = 0;
58 w->active = 0;
59 }
60}
61
62#if IOM_TIME
63void time_watcher::trigger ()
64{
65 call (*this);
66
42 iom.reg (this); 67 iom.reg (this);
43} 68}
44 69
45void time_watcher::trigger () 70void io_manager::reg (time_watcher *w) { reg (w, tw); }
46{ 71void io_manager::unreg (time_watcher *w) { unreg (w, tw); }
47 iom.unreg (this); 72#endif
48 call (at);
49 iom.reg (this);
50}
51 73
52void time_watcher::start () 74#if IOM_IO
53{ 75void 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) 76void io_manager::unreg (io_watcher *w) { unreg (w, iow); }
70{ 77#endif
71 unsigned int sz = iow.size ();
72 unsigned int i = find (iow.begin (), iow.end (), w) - iow.begin ();
73 78
74 if (i != sz) 79#if IOM_CHECK
80void io_manager::reg (check_watcher *w) { reg (w, cw); }
81void io_manager::unreg (check_watcher *w) { unreg (w, cw); }
82#endif
83
84#if IOM_IDLE
85void io_manager::reg (idle_watcher *w) { reg (w, iw); }
86void io_manager::unreg (idle_watcher *w) { unreg (w, iw); }
87#endif
88
89#if IOM_TIME
90inline void set_now (void)
91{
92 struct timeval tv;
93
94 gettimeofday (&tv, 0);
95
96 NOW = (tstamp)tv.tv_sec + (tstamp)tv.tv_usec / 1000000;
97#endif
98}
99
100void io_manager::loop ()
101{
102#if IOM_TIME
103 set_now ();
104#endif
105
106 for (;;)
75 { 107 {
76 if (sz == 1) 108 struct timeval *to = 0;
109 struct timeval tval;
110
111#if IOM_IDLE
112 if (iw.size ())
77 { 113 {
78 pfs.clear (); 114 tval.tv_sec = 0;
79 iow.clear (); 115 tval.tv_usec = 0;
80 } 116 to = &tval;
81 else if (i == sz - 1)
82 {
83 iow.pop_back ();
84 pfs.pop_back ();
85 } 117 }
86 else 118 else
119#endif
87 { 120 {
88 iow[i] = iow[sz - 1]; iow.pop_back (); 121#if IOM_TIME
89 pfs[i] = pfs[sz - 1]; pfs.pop_back (); 122 time_watcher *next;
123
124 for (;;)
125 {
126 next = tw[0]; // the first time-watcher must exist at ALL times
127
128 for (int i = tw.size (); i--; )
129 if (!tw[i])
130 tw.erase_unordered (i);
131 else if (tw[i]->at < next->at)
132 next = tw[i];
133
134 if (next->at > NOW)
135 {
136 if (next != tw[0])
137 {
138 double diff = next->at - NOW;
139 tval.tv_sec = (int)diff;
140 tval.tv_usec = (int)((diff - tval.tv_sec) * 1000000);
141 to = &tval;
142 }
143 break;
144 }
145 else
146 {
147 unreg (next);
148 next->call (*next);
149 }
150 }
151#endif
90 } 152 }
153
154#if IOM_CHECK
155 for (int i = cw.size (); i--; )
156 if (!cw[i])
157 cw.erase_unordered (i);
158 else
159 cw[i]->call (*cw[i]);
160#endif
161
162#if IOM_IO
163 fd_set rfd, wfd, efd;
164
165 FD_ZERO (&rfd);
166 FD_ZERO (&wfd);
167
168 int fds = 0;
169
170 for (io_manager_vec<io_watcher>::iterator i = iow.end (); i-- > iow.begin (); )
171 if (*i)
172 {
173 if ((*i)->events & EVENT_READ ) FD_SET ((*i)->fd, &rfd);
174 if ((*i)->events & EVENT_WRITE) FD_SET ((*i)->fd, &wfd);
175
176 if ((*i)->fd >= fds) fds = (*i)->fd + 1;
177 }
178
179 if (!to && !fds) //TODO: also check idle_watchers and check_watchers
180 break; // no events
181
182 fds = select (fds, &rfd, &wfd, &efd, to);
183# if IOM_TIME
184 set_now ();
185# endif
186
187 if (fds > 0)
188 for (int i = iow.size (); i--; )
189 if (!iow[i])
190 iow.erase_unordered (i);
191 else
192 {
193 short revents = iow[i]->events;
194
195 if (!FD_ISSET (iow[i]->fd, &rfd)) revents &= ~EVENT_READ;
196 if (!FD_ISSET (iow[i]->fd, &wfd)) revents &= ~EVENT_WRITE;
197
198 if (revents)
199 iow[i]->call (*iow[i], revents);
200 }
201 else if (fds < 0 && errno != EINTR)
202 {
203 perror ("Error while waiting for I/O or time event");
204 abort ();
205 }
206#if IOM_IDLE
207 else
208 for (int i = iw.size (); i--; )
209 if (!iw[i])
210 iw.erase_unordered (i);
211 else
212 iw[i]->call (*iw[i]);
213#endif
214
215#elif IOM_TIME
216 if (!to)
217 break;
218
219 select (0, 0, 0, 0, &to);
220 set_now ();
221#else
222 break;
223#endif
91 } 224 }
92} 225}
93 226
94void io_manager::reg (time_watcher *w) 227// this is a dummy time watcher to ensure that the first
95{ 228// time watcher is _always_ valid, this gets rid of a lot
96 tw.push_back (w); 229// of null-pointer-checks
97 push_heap (tw.begin (), tw.end (), lowest_first); 230static struct tw0 : time_watcher {
98} 231 void cb (time_watcher &w)
99
100void io_manager::unreg (time_watcher *w)
101{
102 unsigned int sz = tw.size ();
103 unsigned int i = find (tw.begin (), tw.end (), w) - tw.begin ();
104
105 if (i != sz)
106 { 232 {
107 if (i != sz - 1) 233 // should never get called
108 tw[i] = tw[sz - 1]; 234 // reached end-of-time, or tstamp has a bogus definition :)
235 abort ();
236 }
109 237
110 tw.pop_back (); 238 tw0()
111 make_heap (tw.begin (), tw.end (), lowest_first); 239 : time_watcher (this, &tw0::cb)
112 } 240 { }
113} 241} tw0;
114 242
115inline void set_now (void) 243io_manager::io_manager ()
116{ 244{
117 struct timeval tv; 245 iom_valid = true;
118 246
119 gettimeofday (&tv, 0); 247#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 (); 248 set_now ();
127 249
128 for (;;) 250 tw0.start (TSTAMP_MAX);
129 { 251#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} 252}
170 253
171io_manager::~io_manager () 254io_manager::~io_manager ()
172{ 255{
173 // 256 iom_valid = false;
174} 257}
175 258

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