intial checkin of the libosmocore project
diff --git a/src/select.c b/src/select.c
new file mode 100644
index 0000000..4f5d7ed
--- /dev/null
+++ b/src/select.c
@@ -0,0 +1,128 @@
+/* select filedescriptor handling, taken from:
+ * userspace logging daemon for the iptables ULOG target
+ * of the linux 2.4 netfilter subsystem.
+ *
+ * (C) 2000-2009 by Harald Welte <laforge@gnumonks.org>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2
+ * as published by the Free Software Foundation
+ *
+ * This program 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 General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ */
+
+#include <fcntl.h>
+#include <osmocore/select.h>
+#include <osmocore/linuxlist.h>
+#include <osmocore/timer.h>
+
+#ifdef HAVE_SYS_SELECT_H
+
+static int maxfd = 0;
+static LLIST_HEAD(bsc_fds);
+static int unregistered_count;
+
+int bsc_register_fd(struct bsc_fd *fd)
+{
+ int flags;
+
+ /* make FD nonblocking */
+ flags = fcntl(fd->fd, F_GETFL);
+ if (flags < 0)
+ return flags;
+ flags |= O_NONBLOCK;
+ flags = fcntl(fd->fd, F_SETFL, flags);
+ if (flags < 0)
+ return flags;
+
+ /* Register FD */
+ if (fd->fd > maxfd)
+ maxfd = fd->fd;
+
+ llist_add_tail(&fd->list, &bsc_fds);
+
+ return 0;
+}
+
+void bsc_unregister_fd(struct bsc_fd *fd)
+{
+ unregistered_count++;
+ llist_del(&fd->list);
+}
+
+int bsc_select_main(int polling)
+{
+ struct bsc_fd *ufd, *tmp;
+ fd_set readset, writeset, exceptset;
+ int work = 0, rc;
+ struct timeval no_time = {0, 0};
+
+ FD_ZERO(&readset);
+ FD_ZERO(&writeset);
+ FD_ZERO(&exceptset);
+
+ /* prepare read and write fdsets */
+ llist_for_each_entry(ufd, &bsc_fds, list) {
+ if (ufd->when & BSC_FD_READ)
+ FD_SET(ufd->fd, &readset);
+
+ if (ufd->when & BSC_FD_WRITE)
+ FD_SET(ufd->fd, &writeset);
+
+ if (ufd->when & BSC_FD_EXCEPT)
+ FD_SET(ufd->fd, &exceptset);
+ }
+
+ bsc_timer_check();
+
+ if (!polling)
+ bsc_prepare_timers();
+ rc = select(maxfd+1, &readset, &writeset, &exceptset, polling ? &no_time : bsc_nearest_timer());
+ if (rc < 0)
+ return 0;
+
+ /* fire timers */
+ bsc_update_timers();
+
+ /* call registered callback functions */
+restart:
+ unregistered_count = 0;
+ llist_for_each_entry_safe(ufd, tmp, &bsc_fds, list) {
+ int flags = 0;
+
+ if (FD_ISSET(ufd->fd, &readset)) {
+ flags |= BSC_FD_READ;
+ FD_CLR(ufd->fd, &readset);
+ }
+
+ if (FD_ISSET(ufd->fd, &writeset)) {
+ flags |= BSC_FD_WRITE;
+ FD_CLR(ufd->fd, &writeset);
+ }
+
+ if (FD_ISSET(ufd->fd, &exceptset)) {
+ flags |= BSC_FD_EXCEPT;
+ FD_CLR(ufd->fd, &exceptset);
+ }
+
+ if (flags) {
+ work = 1;
+ ufd->cb(ufd, flags);
+ }
+ /* ugly, ugly hack. If more than one filedescriptors were
+ * unregistered, they might have been consecutive and
+ * llist_for_each_entry_safe() is no longer safe */
+ if (unregistered_count > 1)
+ goto restart;
+ }
+ return work;
+}
+
+#endif /* _HAVE_SYS_SELECT_H */