summaryrefslogtreecommitdiff
path: root/src/poll.cpp
blob: 048de972b6dcd6f73ca05745c1eef31327ad9497 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
/*
    Copyright (c) 2009-2012 250bpm s.r.o.
    Copyright (c) 2007-2009 iMatix Corporation
    Copyright (c) 2007-2011 Other contributors as noted in the AUTHORS file

    This file is part of Crossroads I/O project.

    Crossroads I/O is free software; you can redistribute it and/or modify it
    under the terms of the GNU Lesser General Public License as published by
    the Free Software Foundation; either version 3 of the License, or
    (at your option) any later version.

    Crossroads is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    GNU Lesser General Public License for more details.

    You should have received a copy of the GNU Lesser General Public License
    along with this program.  If not, see <http://www.gnu.org/licenses/>.
*/

#include "poll.hpp"

#if defined XS_USE_ASYNC_POLL

#include <algorithm>

#include "err.hpp"
#include "config.hpp"

xs::poll_t::poll_t (xs::ctx_t *ctx_, uint32_t tid_) :
    io_thread_t (ctx_, tid_),
    retired (false),
    stopping (false)
{
}

xs::poll_t::~poll_t ()
{
    thread_stop (&worker);
}

xs::handle_t xs::poll_t::add_fd (fd_t fd_, i_poll_events *events_)
{
    //  If the file descriptor table is too small expand it.
    fd_table_t::size_type sz = fd_table.size ();
    if (sz <= (fd_table_t::size_type) fd_) {
        fd_table.resize (fd_ + 1);
        while (sz != (fd_table_t::size_type) (fd_ + 1)) {
            fd_table [sz].index = retired_fd;
            ++sz;
        }
    }

    pollfd pfd = {fd_, 0, 0};
    pollset.push_back (pfd);
    assert (fd_table [fd_].index == retired_fd);

    fd_table [fd_].index = pollset.size() - 1;
    fd_table [fd_].events = events_;

    //  Increase the load metric of the thread.
    adjust_load (1);

    return fdtoptr (fd_);
}

void xs::poll_t::rm_fd (handle_t handle_)
{
    int index = fd_table [ptrtofd (handle_)].index;
    assert (index != retired_fd);

    //  Mark the fd as unused.
    pollset [index].fd = retired_fd;
    fd_table [ptrtofd (handle_)].index = retired_fd;
    retired = true;

    //  Decrease the load metric of the thread.
    adjust_load (-1);
}

void xs::poll_t::set_pollin (handle_t handle_)
{
    int index = fd_table [ptrtofd (handle_)].index;
    pollset [index].events |= POLLIN;
}

void xs::poll_t::reset_pollin (handle_t handle_)
{
    int index = fd_table [ptrtofd (handle_)].index;
    pollset [index].events &= ~((short) POLLIN);
}

void xs::poll_t::set_pollout (handle_t handle_)
{
    int index = fd_table [ptrtofd (handle_)].index;
    pollset [index].events |= POLLOUT;
}

void xs::poll_t::reset_pollout (handle_t handle_)
{
    int index = fd_table [ptrtofd (handle_)].index;
    pollset [index].events &= ~((short) POLLOUT);
}

void xs::poll_t::xstart ()
{
    thread_start (&worker, worker_routine, this);
}

void xs::poll_t::xstop ()
{
    stopping = true;
}

void xs::poll_t::loop ()
{
    while (!stopping) {

        //  Execute any due timers.
        int timeout = (int) execute_timers ();

        //  Wait for events.
        int rc = poll (&pollset [0], pollset.size (), timeout ? timeout : -1);
        if (rc == -1 && errno == EINTR)
            continue;
        errno_assert (rc != -1);


        //  If there are no events (i.e. it's a timeout) there's no point
        //  in checking the pollset.
        if (rc == 0)
            continue;

        for (pollset_t::size_type i = 0; i != pollset.size (); i++) {

            xs_assert (!(pollset [i].revents & POLLNVAL));
            if (pollset [i].fd == retired_fd)
               continue;
            if (pollset [i].revents & (POLLERR | POLLHUP))
                fd_table [pollset [i].fd].events->in_event (pollset [i].fd);
            if (pollset [i].fd == retired_fd)
               continue;
            if (pollset [i].revents & POLLOUT)
                fd_table [pollset [i].fd].events->out_event (pollset [i].fd);
            if (pollset [i].fd == retired_fd)
               continue;
            if (pollset [i].revents & POLLIN)
                fd_table [pollset [i].fd].events->in_event (pollset [i].fd);
        }

        //  Clean up the pollset and update the fd_table accordingly.
        if (retired) {
            pollset_t::size_type i = 0;
            while (i < pollset.size ()) {
                if (pollset [i].fd == retired_fd)
                    pollset.erase (pollset.begin () + i);
                else {
                    fd_table [pollset [i].fd].index = i;
                    i ++;
                }
            }
            retired = false;
        }
    }
}

void xs::poll_t::worker_routine (void *arg_)
{
    ((poll_t*) arg_)->loop ();
}

#endif