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Comparing gvpe/src/iom.C (file contents):
Revision 1.12 by pcg, Thu Oct 16 02:41:21 2003 UTC vs.
Revision 1.13 by pcg, Sat Jan 17 01:18:36 2004 UTC

1/* 1/*
2 iom.C -- generic I/O multiplexor 2 iom.C -- generic I/O multiplexor
3 Copyright (C) 2003 Marc Lehmann <pcg@goof.com> 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 "gettext.h"
28
29#include "slog.h"
30#include "iom.h" 27#include "iom.h"
31 28
29// TSTAMP_MAX must still fit into a positive struct timeval
30#define TSTAMP_MAX (double)(1UL<<31)
31
32tstamp NOW; 32tstamp NOW;
33bool iom_valid; 33static bool iom_valid;
34io_manager iom; 34io_manager iom;
35 35
36inline bool earliest_first (const time_watcher *a, const time_watcher *b) 36template<class watcher>
37void io_manager::reg (watcher *w, io_manager_vec<watcher> &queue)
37{ 38{
38 return a->at > b->at; 39 if (!iom_valid)
39} 40 abort ();
40 41
41void time_watcher::set (tstamp when) 42 if (!w->active)
42{ 43 {
43 at = when; 44 queue.push_back (w);
44 45 w->active = queue.size ();
45 if (registered) 46 }
46 iom.reschedule_time_watchers ();
47} 47}
48 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
49void time_watcher::trigger () 63void time_watcher::trigger ()
50{ 64{
51 call (*this); 65 call (*this);
52 66
53 if (registered)
54 iom.reschedule_time_watchers ();
55 else
56 iom.reg (this); 67 iom.reg (this);
57} 68}
58 69
59time_watcher::~time_watcher () 70void io_manager::reg (time_watcher *w) { reg (w, tw); }
60{ 71void io_manager::unreg (time_watcher *w) { unreg (w, tw); }
61 if (iom_valid) 72#endif
62 iom.unreg (this);
63}
64 73
65void io_watcher::set(int fd_, short events_) 74#if IOM_IO
66{ 75void io_manager::reg (io_watcher *w) { reg (w, iow); }
67 fd = fd_; 76void io_manager::unreg (io_watcher *w) { unreg (w, iow); }
68 events = events_; 77#endif
69 78
70 if (registered) 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 (;;)
71 { 107 {
72 iom.unreg (this); 108 struct timeval *to = 0;
73 iom.reg (this); 109 struct timeval tval;
74 }
75}
76 110
77io_watcher::~io_watcher () 111#if IOM_IDLE
78{ 112 if (iw.size ())
79 if (iom_valid)
80 iom.unreg (this);
81}
82
83void io_manager::reg (io_watcher *w)
84{
85 if (!w->registered)
86 {
87 w->registered = true;
88
89 pollfd pfd;
90
91 pfd.fd = w->fd;
92 pfd.events = w->events;
93
94 pfs.push_back (pfd);
95 iow.push_back (w);
96 }
97}
98
99void io_manager::unreg (io_watcher *w)
100{
101 if (w->registered)
102 {
103 w->registered = false;
104
105 unsigned int sz = iow.size ();
106 unsigned int i = find (iow.begin (), iow.end (), w) - iow.begin ();
107
108 assert (i != sz);
109
110 if (sz == 1)
111 { 113 {
112 pfs.clear (); 114 tval.tv_sec = 0;
113 iow.clear (); 115 tval.tv_usec = 0;
114 } 116 to = &tval;
115 else if (i == sz - 1)
116 {
117 iow.pop_back ();
118 pfs.pop_back ();
119 } 117 }
120 else 118 else
119#endif
121 { 120 {
122 iow[i] = iow[sz - 1]; iow.pop_back (); 121#if IOM_TIME
123 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
124 } 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
125 } 224 }
126} 225}
127 226
128void io_manager::reschedule_time_watchers () 227// this is a dummy time watcher to ensure that the first
129{ 228// time watcher is _always_ valid, this gets rid of a lot
130 make_heap (tw.begin (), tw.end (), earliest_first); 229// of null-pointer-checks
131} 230static struct tw0 : time_watcher {
132 231 void cb (time_watcher &w)
133void io_manager::reg (time_watcher *w)
134{
135 if (!w->registered)
136 { 232 {
137 w->registered = true; 233 // should never get called
234 // reached end-of-time, or tstamp has a bogus definition :)
235 abort ();
236 }
138 237
139 tw.push_back (w); 238 tw0()
140 push_heap (tw.begin (), tw.end (), earliest_first); 239 : time_watcher (this, &tw0::cb)
141 } 240 { }
142} 241} tw0;
143 242
144void io_manager::unreg (time_watcher *w) 243io_manager::io_manager ()
145{ 244{
146 if (w->registered) 245 iom_valid = true;
147 {
148 w->registered = false;
149 246
150 unsigned int sz = tw.size (); 247#if IOM_TIME
151 unsigned int i = find (tw.begin (), tw.end (), w) - tw.begin ();
152
153 assert (i != sz);
154
155 if (i != sz - 1)
156 tw[i] = tw[sz - 1];
157
158 tw.pop_back ();
159 reschedule_time_watchers ();
160 }
161}
162
163inline void set_now (void)
164{
165 struct timeval tv;
166
167 gettimeofday (&tv, 0);
168
169 NOW = (tstamp)tv.tv_sec + (tstamp)tv.tv_usec / 1000000;
170}
171
172void io_manager::loop ()
173{
174 set_now (); 248 set_now ();
175 249
176 for (;;) 250 tw0.start (TSTAMP_MAX);
177 { 251#endif
178 while (tw[0]->at <= NOW)
179 {
180 // remove the first watcher
181 time_watcher *w = tw[0];
182
183 pop_heap (tw.begin (), tw.end (), earliest_first);
184 tw.pop_back ();
185
186 w->registered = false;
187
188 // call it
189 w->call (*w);
190
191 // re-add it if necessary
192 if (w->at >= 0 && !w->registered)
193 reg (w);
194 }
195
196 int timeout = (int) ((tw[0]->at - NOW) * 1000);
197
198 int fds = poll (&pfs[0], pfs.size (), timeout);
199
200 set_now ();
201
202 vector<io_watcher *>::iterator w;
203 vector<pollfd>::iterator p;
204
205 for (w = iow.begin (), p = pfs.begin ();
206 fds > 0 && w < iow.end ();
207 ++w, ++p)
208 if (p->revents)
209 {
210 --fds;
211
212 if (p->revents & POLLNVAL)
213 {
214 slog (L_ERR, _("io_watcher started on illegal file descriptor, disabling."));
215 (*w)->stop ();
216 }
217 else
218 (*w)->call (**w, p->revents);
219 }
220 }
221}
222
223void io_manager::idle_cb (time_watcher &w)
224{
225 w.at = NOW + 86400; // wake up every day, for no good reason
226}
227
228io_manager::io_manager ()
229{
230 iom_valid = true;
231
232 set_now ();
233 idle = new time_watcher (this, &io_manager::idle_cb);
234 idle->start (0);
235} 252}
236 253
237io_manager::~io_manager () 254io_manager::~io_manager ()
238{ 255{
239 iom_valid = false; 256 iom_valid = false;

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