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Comparing gvpe/src/iom.C (file contents):
Revision 1.11 by pcg, Sat Apr 5 02:32:40 2003 UTC vs.
Revision 1.18 by pcg, Sun Mar 28 01:43:50 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 "gettext.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>
27 34
28#include "slog.h"
29#include "iom.h" 35#include "iom.h"
30 36
37// TSTAMP_MAX must still fit into a positive struct timeval
38#define TSTAMP_MAX (double)(1UL<<31)
39
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;
58
31tstamp NOW; 59tstamp NOW;
32bool iom_valid; 60static bool iom_valid;
33io_manager iom; 61io_manager iom;
34 62
35inline bool earliest_first (const time_watcher *a, const time_watcher *b) 63template<class watcher>
64void io_manager::reg (watcher *w, io_manager_vec<watcher> &queue)
36{ 65{
37 return a->at > b->at; 66 if (!iom_valid)
38} 67 abort ();
39 68
40void time_watcher::set (tstamp when) 69 if (!w->active)
41{ 70 {
42 at = when; 71#if IOM_CHECK
43 72 queue.activity = true;
44 if (registered) 73#endif
45 iom.reschedule_time_watchers (); 74 queue.push_back (w);
75 w->active = queue.size ();
76 }
46} 77}
47 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
48void time_watcher::trigger () 93void time_watcher::trigger ()
49{ 94{
50 call (*this); 95 call (*this);
51 96
52 if (registered)
53 iom.reschedule_time_watchers ();
54 else
55 iom.reg (this); 97 iom.reg (this);
56} 98}
57 99
58time_watcher::~time_watcher () 100void io_manager::reg (time_watcher *w) { reg (w, tw); }
59{ 101void io_manager::unreg (time_watcher *w) { unreg (w, tw); }
60 if (iom_valid) 102#endif
61 iom.unreg (this);
62}
63 103
64void io_watcher::set(int fd_, short events_) 104#if IOM_IO
65{
66 fd = fd_;
67 events = events_;
68
69 if (registered)
70 {
71 iom.unreg (this);
72 iom.reg (this);
73 }
74}
75
76io_watcher::~io_watcher ()
77{
78 if (iom_valid)
79 iom.unreg (this);
80}
81
82void io_manager::reg (io_watcher *w) 105void io_manager::reg (io_watcher *w) { reg (w, iow); }
83{ 106void io_manager::unreg (io_watcher *w) { unreg (w, iow); }
84 if (!w->registered) 107#endif
85 {
86 w->registered = true;
87 108
88 pollfd pfd; 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
89 113
90 pfd.fd = w->fd; 114#if IOM_IDLE
91 pfd.events = w->events; 115void io_manager::reg (idle_watcher *w) { reg (w, iw); }
116void io_manager::unreg (idle_watcher *w) { unreg (w, iw); }
117#endif
92 118
93 pfs.push_back (pfd); 119#if IOM_TIME
94 iow.push_back (w); 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 (;;)
95 } 137 {
96} 138 struct timeval *to = 0;
139 struct timeval tval;
97 140
98void io_manager::unreg (io_watcher *w) 141#if IOM_IDLE
99{ 142 if (iw.size ())
100 if (w->registered)
101 {
102 w->registered = false;
103
104 unsigned int sz = iow.size ();
105 unsigned int i = find (iow.begin (), iow.end (), w) - iow.begin ();
106
107 assert (i != sz);
108
109 if (sz == 1)
110 {
111 pfs.clear ();
112 iow.clear ();
113 } 143 {
114 else if (i == sz - 1) 144 tval.tv_sec = 0;
115 { 145 tval.tv_usec = 0;
116 iow.pop_back (); 146 to = &tval;
117 pfs.pop_back ();
118 } 147 }
119 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)
120 { 213 {
121 iow[i] = iow[sz - 1]; iow.pop_back (); 214 if ((*i)->events & EVENT_READ ) FD_SET ((*i)->fd, &rfd);
122 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;
123 } 218 }
124 }
125}
126 219
127void io_manager::reschedule_time_watchers () 220 if (!to && !fds) //TODO: also check idle_watchers and check_watchers
128{ 221 break; // no events
129 make_heap (tw.begin (), tw.end (), earliest_first);
130}
131 222
132void io_manager::reg (time_watcher *w) 223 fds = select (fds, &rfd, &wfd, &efd, to);
133{ 224# if IOM_TIME
134 if (!w->registered) 225 set_now ();
135 { 226# endif
136 w->registered = true;
137 227
138 tw.push_back (w); 228 if (fds > 0)
139 push_heap (tw.begin (), tw.end (), earliest_first); 229 for (int i = iow.size (); i--; )
140 } 230 if (!iow[i])
141} 231 iow.erase_unordered (i);
232 else
233 {
234 short revents = iow[i]->events;
142 235
143void io_manager::unreg (time_watcher *w) 236 if (!FD_ISSET (iow[i]->fd, &rfd)) revents &= ~EVENT_READ;
144{ 237 if (!FD_ISSET (iow[i]->fd, &wfd)) revents &= ~EVENT_WRITE;
145 if (w->registered)
146 {
147 w->registered = false;
148 238
149 unsigned int sz = tw.size (); 239 if (revents)
150 unsigned int i = find (tw.begin (), tw.end (), w) - tw.begin (); 240 iow[i]->call (*iow[i], revents);
151 241 }
152 assert (i != sz); 242 else if (fds < 0 && errno != EINTR)
153 243 {
154 if (i != sz - 1) 244 perror ("Error while waiting for I/O or time event");
155 tw[i] = tw[sz - 1]; 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
156 255
157 tw.pop_back (); 256#elif IOM_TIME
158 reschedule_time_watchers (); 257 if (!to)
159 } 258 break;
160}
161 259
162inline void set_now (void) 260 select (0, 0, 0, 0, &to);
163{ 261 set_now ();
164 struct timeval tv; 262#else
263 break;
264#endif
165 265
166 gettimeofday (&tv, 0); 266 }
167
168 NOW = (tstamp)tv.tv_sec + (tstamp)tv.tv_usec / 1000000;
169} 267}
170 268
171void io_manager::loop () 269io_manager::io_manager ()
172{ 270{
271 iom_valid = true;
272
273#if IOM_TIME
173 set_now (); 274 set_now ();
174 275
175 for (;;) 276 tw0.start (TSTAMP_MAX);
176 { 277#endif
177 while (tw[0]->at <= NOW)
178 {
179 // remove the first watcher
180 time_watcher *w = tw[0];
181
182 pop_heap (tw.begin (), tw.end (), earliest_first);
183 tw.pop_back ();
184
185 w->registered = false;
186
187 // call it
188 w->call (*w);
189
190 // re-add it if necessary
191 if (w->at >= 0 && !w->registered)
192 reg (w);
193 }
194
195 int timeout = (int) ((tw[0]->at - NOW) * 1000);
196
197 int fds = poll (&pfs[0], pfs.size (), timeout);
198
199 set_now ();
200
201 vector<io_watcher *>::iterator w;
202 vector<pollfd>::iterator p;
203
204 for (w = iow.begin (), p = pfs.begin ();
205 fds > 0 && w < iow.end ();
206 ++w, ++p)
207 if (p->revents)
208 {
209 --fds;
210
211 if (p->revents & POLLNVAL)
212 {
213 slog (L_ERR, _("io_watcher started on illegal file descriptor, disabling."));
214 (*w)->stop ();
215 }
216 else
217 (*w)->call (**w, p->revents);
218 }
219 }
220}
221
222void io_manager::idle_cb (time_watcher &w)
223{
224 w.at = NOW + 86400; // wake up every day, for no good reason
225}
226
227io_manager::io_manager ()
228{
229 iom_valid = true;
230
231 set_now ();
232 idle = new time_watcher (this, &io_manager::idle_cb);
233 idle->start (0);
234} 278}
235 279
236io_manager::~io_manager () 280io_manager::~io_manager ()
237{ 281{
238 iom_valid = false; 282 iom_valid = false;

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