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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 1.14 by pcg, Sat Jan 17 14:08:57 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
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;
49
32tstamp NOW; 50tstamp NOW;
33bool iom_valid; 51static bool iom_valid;
34io_manager iom; 52io_manager iom;
35 53
36inline bool earliest_first (const time_watcher *a, const time_watcher *b) 54template<class watcher>
55void io_manager::reg (watcher *w, io_manager_vec<watcher> &queue)
37{ 56{
38 return a->at > b->at; 57 if (!iom_valid)
39} 58 abort ();
40 59
41void time_watcher::set (tstamp when) 60 if (!w->active)
42{ 61 {
43 at = when; 62 queue.push_back (w);
44 63 w->active = queue.size ();
45 if (registered) 64 }
46 iom.reschedule_time_watchers ();
47} 65}
48 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
49void time_watcher::trigger () 81void time_watcher::trigger ()
50{ 82{
51 call (*this); 83 call (*this);
52 84
53 if (registered)
54 iom.reschedule_time_watchers ();
55 else
56 iom.reg (this); 85 iom.reg (this);
57} 86}
58 87
59time_watcher::~time_watcher () 88void io_manager::reg (time_watcher *w) { reg (w, tw); }
60{ 89void io_manager::unreg (time_watcher *w) { unreg (w, tw); }
61 if (iom_valid) 90#endif
62 iom.unreg (this);
63}
64 91
65void io_watcher::set(int fd_, short events_) 92#if IOM_IO
66{ 93void io_manager::reg (io_watcher *w) { reg (w, iow); }
67 fd = fd_; 94void io_manager::unreg (io_watcher *w) { unreg (w, iow); }
68 events = events_; 95#endif
69 96
70 if (registered) 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 (;;)
71 { 125 {
72 iom.unreg (this); 126 struct timeval *to = 0;
73 iom.reg (this); 127 struct timeval tval;
74 }
75}
76 128
77io_watcher::~io_watcher () 129#if IOM_IDLE
78{ 130 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 { 131 {
112 pfs.clear (); 132 tval.tv_sec = 0;
113 iow.clear (); 133 tval.tv_usec = 0;
114 } 134 to = &tval;
115 else if (i == sz - 1)
116 {
117 iow.pop_back ();
118 pfs.pop_back ();
119 } 135 }
120 else 136 else
137#endif
121 { 138 {
122 iow[i] = iow[sz - 1]; iow.pop_back (); 139#if IOM_TIME
123 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
124 } 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
125 } 242 }
126} 243}
127 244
128void io_manager::reschedule_time_watchers () 245io_manager::io_manager ()
129{ 246{
130 make_heap (tw.begin (), tw.end (), earliest_first); 247 iom_valid = true;
131}
132 248
133void io_manager::reg (time_watcher *w) 249#if IOM_TIME
134{
135 if (!w->registered)
136 {
137 w->registered = true;
138
139 tw.push_back (w);
140 push_heap (tw.begin (), tw.end (), earliest_first);
141 }
142}
143
144void io_manager::unreg (time_watcher *w)
145{
146 if (w->registered)
147 {
148 w->registered = false;
149
150 unsigned int sz = tw.size ();
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 (); 250 set_now ();
175 251
176 for (;;) 252 tw0.start (TSTAMP_MAX);
177 { 253 printf ("abort, %f but inly on %f\n", NOW, tw0.at);
178 while (tw[0]->at <= NOW) 254#endif
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} 255}
236 256
237io_manager::~io_manager () 257io_manager::~io_manager ()
238{ 258{
239 iom_valid = false; 259 iom_valid = false;

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