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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 1.14 by pcg, Sat Jan 17 14:08:57 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
24#include <sys/select.h>
22#include <sys/time.h> 25#include <sys/time.h>
23 26
24#include <algorithm>
25#include <functional>
26
27#include "slog.h"
28
29#include "iom.h" 27#include "iom.h"
30 28
31inline bool lowest_first (const time_watcher *a, const time_watcher *b) 29// TSTAMP_MAX must still fit into a positive struct timeval
32{ 30#define TSTAMP_MAX (double)(1UL<<31)
33 return a->at > b->at; 31
34} 32// this is a dummy time watcher to ensure that the first
33// time watcher is _always_ valid, this gets rid of a lot
34// of null-pointer-checks
35// (must come _before_ iom is being defined)
36static struct tw0 : time_watcher {
37 void cb (time_watcher &w)
38 {
39 // should never get called
40 // reached end-of-time, or tstamp has a bogus definition,
41 // or compiler initilization order broken, or somethine else :)
42 abort ();
43 }
44
45 tw0()
46 : time_watcher (this, &tw0::cb)
47 { }
48} tw0;
35 49
36tstamp NOW; 50tstamp NOW;
37 51static bool iom_valid;
38io_manager iom; 52io_manager iom;
39 53
40void time_watcher::set (tstamp when) 54template<class watcher>
55void io_manager::reg (watcher *w, io_manager_vec<watcher> &queue)
41{ 56{
42 iom.unreg (this); 57 if (!iom_valid)
43 at = when; 58 abort ();
59
60 if (!w->active)
61 {
62 queue.push_back (w);
63 w->active = queue.size ();
64 }
65}
66
67template<class watcher>
68void io_manager::unreg (watcher *w, io_manager_vec<watcher> &queue)
69{
70 if (!iom_valid)
71 return;
72
73 if (w->active)
74 {
75 queue [w->active - 1] = 0;
76 w->active = 0;
77 }
78}
79
80#if IOM_TIME
81void time_watcher::trigger ()
82{
83 call (*this);
84
44 iom.reg (this); 85 iom.reg (this);
45} 86}
46 87
47void io_manager::reg (int fd, short events, io_watcher *w) 88void io_manager::reg (time_watcher *w) { reg (w, tw); }
48{ 89void io_manager::unreg (time_watcher *w) { unreg (w, tw); }
49 pollfd pfd; 90#endif
50 91
51 pfd.fd = fd; 92#if IOM_IO
52 pfd.events = events; 93void 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) 94void io_manager::unreg (io_watcher *w) { unreg (w, iow); }
59{ 95#endif
60 unsigned int sz = iow.size ();
61 unsigned int i = find (iow.begin (), iow.end (), w) - iow.begin ();
62 96
63 if (i != sz) 97#if IOM_CHECK
98void io_manager::reg (check_watcher *w) { reg (w, cw); }
99void io_manager::unreg (check_watcher *w) { unreg (w, cw); }
100#endif
101
102#if IOM_IDLE
103void io_manager::reg (idle_watcher *w) { reg (w, iw); }
104void io_manager::unreg (idle_watcher *w) { unreg (w, iw); }
105#endif
106
107#if IOM_TIME
108inline void set_now (void)
109{
110 struct timeval tv;
111
112 gettimeofday (&tv, 0);
113
114 NOW = (tstamp)tv.tv_sec + (tstamp)tv.tv_usec / 1000000;
115#endif
116}
117
118void io_manager::loop ()
119{
120#if IOM_TIME
121 set_now ();
122#endif
123
124 for (;;)
64 { 125 {
65 if (sz == 1) 126 struct timeval *to = 0;
127 struct timeval tval;
128
129#if IOM_IDLE
130 if (iw.size ())
66 { 131 {
67 pfs.clear (); 132 tval.tv_sec = 0;
68 iow.clear (); 133 tval.tv_usec = 0;
69 } 134 to = &tval;
70 else if (i == sz - 1)
71 {
72 iow.pop_back ();
73 pfs.pop_back ();
74 } 135 }
75 else 136 else
137#endif
76 { 138 {
77 iow[i] = iow[sz - 1]; iow.pop_back (); 139#if IOM_TIME
78 pfs[i] = pfs[sz - 1]; pfs.pop_back (); 140 time_watcher *next;
141
142 for (;;)
143 {
144 next = tw[0]; // the first time-watcher must exist at ALL times
145
146 for (int i = tw.size (); i--; )
147 if (!tw[i])
148 tw.erase_unordered (i);
149 else if (tw[i]->at < next->at)
150 next = tw[i];
151
152 if (next->at > NOW)
153 {
154 if (next != tw[0])
155 {
156 double diff = next->at - NOW;
157 tval.tv_sec = (int)diff;
158 tval.tv_usec = (int)((diff - tval.tv_sec) * 1000000);
159 to = &tval;
160 }
161 break;
162 }
163 else
164 {
165 unreg (next);
166 next->call (*next);
167 }
168 }
169#endif
79 } 170 }
171
172#if IOM_CHECK
173 for (int i = cw.size (); i--; )
174 if (!cw[i])
175 cw.erase_unordered (i);
176 else
177 cw[i]->call (*cw[i]);
178#endif
179
180#if IOM_IO
181 fd_set rfd, wfd, efd;
182
183 FD_ZERO (&rfd);
184 FD_ZERO (&wfd);
185
186 int fds = 0;
187
188 for (io_manager_vec<io_watcher>::iterator i = iow.end (); i-- > iow.begin (); )
189 if (*i)
190 {
191 if ((*i)->events & EVENT_READ ) FD_SET ((*i)->fd, &rfd);
192 if ((*i)->events & EVENT_WRITE) FD_SET ((*i)->fd, &wfd);
193
194 if ((*i)->fd >= fds) fds = (*i)->fd + 1;
195 }
196
197 if (!to && !fds) //TODO: also check idle_watchers and check_watchers
198 break; // no events
199
200 fds = select (fds, &rfd, &wfd, &efd, to);
201# if IOM_TIME
202 set_now ();
203# endif
204
205 if (fds > 0)
206 for (int i = iow.size (); i--; )
207 if (!iow[i])
208 iow.erase_unordered (i);
209 else
210 {
211 short revents = iow[i]->events;
212
213 if (!FD_ISSET (iow[i]->fd, &rfd)) revents &= ~EVENT_READ;
214 if (!FD_ISSET (iow[i]->fd, &wfd)) revents &= ~EVENT_WRITE;
215
216 if (revents)
217 iow[i]->call (*iow[i], revents);
218 }
219 else if (fds < 0 && errno != EINTR)
220 {
221 perror ("Error while waiting for I/O or time event");
222 abort ();
223 }
224#if IOM_IDLE
225 else
226 for (int i = iw.size (); i--; )
227 if (!iw[i])
228 iw.erase_unordered (i);
229 else
230 iw[i]->call (*iw[i]);
231#endif
232
233#elif IOM_TIME
234 if (!to)
235 break;
236
237 select (0, 0, 0, 0, &to);
238 set_now ();
239#else
240 break;
241#endif
80 } 242 }
81} 243}
82 244
83void io_manager::reg (time_watcher *w) 245io_manager::io_manager ()
84{ 246{
85 tw.push_back (w); 247 iom_valid = true;
86 push_heap (tw.begin (), tw.end (), lowest_first);
87}
88 248
89void io_manager::unreg (time_watcher *w) 249#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 (); 250 set_now ();
121 251
122 while (!(iow.empty () && tw.empty ())) 252 tw0.start (TSTAMP_MAX);
123 { 253 printf ("abort, %f but inly on %f\n", NOW, tw0.at);
124 int timeout = tw.empty () 254#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} 255}
157 256
158io_manager::~io_manager () 257io_manager::~io_manager ()
159{ 258{
160 // 259 iom_valid = false;
161} 260}
162 261

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