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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 1.19 by pcg, Sun Mar 28 01:53:33 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
22#include <sys/time.h> 24#include <sys/time.h>
23 25
24#include <algorithm> 26#if 1 // older unices need these includes for select (2)
25#include <functional> 27# include <unistd.h>
28# include <sys/types.h>
29#endif
26 30
27#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>
28 34
29#include "slog.h"
30#include "iom.h" 35#include "iom.h"
31 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
32tstamp NOW; 59tstamp NOW;
33bool iom_valid; 60static bool iom_valid;
34io_manager iom; 61io_manager iom;
35 62
36inline 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)
37{ 65{
38 return a->at > b->at; 66 if (!iom_valid)
39} 67 abort ();
40 68
41void time_watcher::set (tstamp when) 69 if (!w->active)
42{ 70 {
43 at = when; 71#if IOM_CHECK
44 72 queue.activity = true;
45 if (registered) 73#endif
46 iom.reschedule_time_watchers (); 74 queue.push_back (w);
75 w->active = queue.size ();
76 }
47} 77}
48 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
49void time_watcher::trigger () 93void time_watcher::trigger ()
50{ 94{
51 call (*this); 95 call (*this);
52 96
53 if (registered)
54 iom.reschedule_time_watchers ();
55 else
56 iom.reg (this); 97 iom.reg (this);
57} 98}
58 99
59time_watcher::~time_watcher () 100void io_manager::reg (time_watcher *w) { reg (w, tw); }
60{ 101void io_manager::unreg (time_watcher *w) { unreg (w, tw); }
61 if (iom_valid) 102#endif
62 iom.unreg (this);
63}
64 103
65void io_watcher::set(int fd_, short events_) 104#if IOM_IO
66{
67 fd = fd_;
68 events = events_;
69
70 if (registered)
71 {
72 iom.unreg (this);
73 iom.reg (this);
74 }
75}
76
77io_watcher::~io_watcher ()
78{
79 if (iom_valid)
80 iom.unreg (this);
81}
82
83void io_manager::reg (io_watcher *w) 105void io_manager::reg (io_watcher *w) { reg (w, iow); }
84{ 106void io_manager::unreg (io_watcher *w) { unreg (w, iow); }
85 if (!w->registered) 107#endif
86 {
87 w->registered = true;
88 108
89 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
90 113
91 pfd.fd = w->fd; 114#if IOM_IDLE
92 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
93 118
94 pfs.push_back (pfd); 119#if IOM_TIME
95 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 (;;)
96 } 137 {
97} 138 struct timeval *to = 0;
139 struct timeval tval;
98 140
99void io_manager::unreg (io_watcher *w) 141#if IOM_IDLE
100{ 142 if (iw.size ())
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 {
112 pfs.clear ();
113 iow.clear ();
114 } 143 {
115 else if (i == sz - 1) 144 tval.tv_sec = 0;
116 { 145 tval.tv_usec = 0;
117 iow.pop_back (); 146 to = &tval;
118 pfs.pop_back ();
119 } 147 }
120 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)
121 { 213 {
122 iow[i] = iow[sz - 1]; iow.pop_back (); 214 if ((*i)->events & EVENT_READ ) FD_SET ((*i)->fd, &rfd);
123 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;
124 } 218 }
125 }
126}
127 219
128void io_manager::reschedule_time_watchers () 220 if (!to && !fds) //TODO: also check idle_watchers and check_watchers
129{ 221 break; // no events
130 make_heap (tw.begin (), tw.end (), earliest_first);
131}
132 222
133void io_manager::reg (time_watcher *w) 223 fds = select (fds, &rfd, &wfd, NULL, to);
134{ 224# if IOM_TIME
135 if (!w->registered) 225 set_now ();
136 { 226# endif
137 w->registered = true;
138 227
139 tw.push_back (w); 228 if (fds > 0)
140 push_heap (tw.begin (), tw.end (), earliest_first); 229 for (int i = iow.size (); i--; )
141 } 230 if (!iow[i])
142} 231 iow.erase_unordered (i);
232 else
233 {
234 short revents = iow[i]->events;
143 235
144void io_manager::unreg (time_watcher *w) 236 if (!FD_ISSET (iow[i]->fd, &rfd)) revents &= ~EVENT_READ;
145{ 237 if (!FD_ISSET (iow[i]->fd, &wfd)) revents &= ~EVENT_WRITE;
146 if (w->registered)
147 {
148 w->registered = false;
149 238
150 unsigned int sz = tw.size (); 239 if (revents)
151 unsigned int i = find (tw.begin (), tw.end (), w) - tw.begin (); 240 iow[i]->call (*iow[i], revents);
152 241 }
153 assert (i != sz); 242 else if (fds < 0 && errno != EINTR)
154 243 {
155 if (i != sz - 1) 244 perror ("Error while waiting for I/O or time event");
156 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
157 255
158 tw.pop_back (); 256#elif IOM_TIME
159 reschedule_time_watchers (); 257 if (!to)
160 } 258 break;
161}
162 259
163inline void set_now (void) 260 select (0, 0, 0, 0, &to);
164{ 261 set_now ();
165 struct timeval tv; 262#else
263 break;
264#endif
166 265
167 gettimeofday (&tv, 0); 266 }
168
169 NOW = (tstamp)tv.tv_sec + (tstamp)tv.tv_usec / 1000000;
170} 267}
171 268
172void io_manager::loop () 269io_manager::io_manager ()
173{ 270{
271 iom_valid = true;
272
273#if IOM_TIME
174 set_now (); 274 set_now ();
175 275
176 for (;;) 276 tw0.start (TSTAMP_MAX);
177 { 277#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} 278}
236 279
237io_manager::~io_manager () 280io_manager::~io_manager ()
238{ 281{
239 iom_valid = false; 282 iom_valid = false;

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