* net/dbus.el (dbus--init-bus): Declare function.
[emacs.git] / src / xgselect.c
bloba281414610a9ab1e7f252155c32c7934779b668e
1 /* Function for handling the GLib event loop.
3 Copyright (C) 2009-2014 Free Software Foundation, Inc.
5 This file is part of GNU Emacs.
7 GNU Emacs is free software: you can redistribute it and/or modify
8 it under the terms of the GNU General Public License as published by
9 the Free Software Foundation, either version 3 of the License, or
10 (at your option) any later version.
12 GNU Emacs is distributed in the hope that it will be useful,
13 but WITHOUT ANY WARRANTY; without even the implied warranty of
14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 GNU General Public License for more details.
17 You should have received a copy of the GNU General Public License
18 along with GNU Emacs. If not, see <http://www.gnu.org/licenses/>. */
20 #include <config.h>
22 #include "xgselect.h"
24 #ifdef HAVE_GLIB
26 #include <glib.h>
27 #include <errno.h>
28 #include <timespec.h>
29 #include "frame.h"
31 int
32 xg_select (int fds_lim, fd_set *rfds, fd_set *wfds, fd_set *efds,
33 struct timespec const *timeout, sigset_t const *sigmask)
35 fd_set all_rfds, all_wfds;
36 struct timespec tmo;
37 struct timespec const *tmop = timeout;
39 GMainContext *context;
40 int have_wfds = wfds != NULL;
41 GPollFD gfds_buf[128];
42 GPollFD *gfds = gfds_buf;
43 int gfds_size = sizeof gfds_buf / sizeof *gfds_buf;
44 int n_gfds, retval = 0, our_fds = 0, max_fds = fds_lim - 1;
45 int i, nfds, tmo_in_millisec;
46 USE_SAFE_ALLOCA;
48 /* Do not try to optimize with an initial check with g_main_context_pending
49 and a call to pselect if it returns false. If Gdk has a timeout for 0.01
50 second, and Emacs has a timeout for 1 second, g_main_context_pending will
51 return false, but the timeout will be 1 second, thus missing the gdk
52 timeout with a lot. */
54 context = g_main_context_default ();
56 if (rfds) all_rfds = *rfds;
57 else FD_ZERO (&all_rfds);
58 if (wfds) all_wfds = *wfds;
59 else FD_ZERO (&all_wfds);
61 n_gfds = g_main_context_query (context, G_PRIORITY_LOW, &tmo_in_millisec,
62 gfds, gfds_size);
63 if (gfds_size < n_gfds)
65 SAFE_NALLOCA (gfds, sizeof *gfds, n_gfds);
66 gfds_size = n_gfds;
67 n_gfds = g_main_context_query (context, G_PRIORITY_LOW, &tmo_in_millisec,
68 gfds, gfds_size);
71 for (i = 0; i < n_gfds; ++i)
73 if (gfds[i].events & G_IO_IN)
75 FD_SET (gfds[i].fd, &all_rfds);
76 if (gfds[i].fd > max_fds) max_fds = gfds[i].fd;
78 if (gfds[i].events & G_IO_OUT)
80 FD_SET (gfds[i].fd, &all_wfds);
81 if (gfds[i].fd > max_fds) max_fds = gfds[i].fd;
82 have_wfds = 1;
86 SAFE_FREE ();
88 if (tmo_in_millisec >= 0)
90 tmo = make_timespec (tmo_in_millisec / 1000,
91 1000 * 1000 * (tmo_in_millisec % 1000));
92 if (!timeout || timespec_cmp (tmo, *timeout) < 0)
93 tmop = &tmo;
96 fds_lim = max_fds + 1;
97 nfds = pselect (fds_lim, &all_rfds, have_wfds ? &all_wfds : NULL,
98 efds, tmop, sigmask);
100 if (nfds < 0)
101 retval = nfds;
102 else if (nfds > 0)
104 for (i = 0; i < fds_lim; ++i)
106 if (FD_ISSET (i, &all_rfds))
108 if (rfds && FD_ISSET (i, rfds)) ++retval;
109 else ++our_fds;
111 else if (rfds)
112 FD_CLR (i, rfds);
114 if (have_wfds && FD_ISSET (i, &all_wfds))
116 if (wfds && FD_ISSET (i, wfds)) ++retval;
117 else ++our_fds;
119 else if (wfds)
120 FD_CLR (i, wfds);
122 if (efds && FD_ISSET (i, efds))
123 ++retval;
127 /* If Gtk+ is in use eventually gtk_main_iteration will be called,
128 unless retval is zero. */
129 #ifdef USE_GTK
130 if (retval == 0)
131 #endif
132 while (g_main_context_pending (context))
133 g_main_context_dispatch (context);
135 /* To not have to recalculate timeout, return like this. */
136 if ((our_fds > 0 || (nfds == 0 && tmop == &tmo)) && (retval == 0))
138 retval = -1;
139 errno = EINTR;
142 return retval;
144 #endif /* HAVE_GLIB */