An application that has own events and file descriptors, must poll

select function ob libbsc. A "polling" flag is used to enable polling.
In this case select() will not sleep until file descriptor events occurr
or nearest timer expires. Also a return value will indicate if there was
an event that has been handled. If there was an event, the application
decides to poll again and don't wait.

In case for bsc_hack, the polling flag is not set. select will sleep as
usual.

(Andreas Eversberg)

7 files changed, 18 insertions, 14 deletions

diff --git a/include/openbsc/select.h b/include/openbsc/select.h
index b677162e6..c2af1d787 100644
--- a/include/openbsc/select.h
+++ b/include/openbsc/select.h
@@ -18,5 +18,5 @@ struct bsc_fd {
 
 int bsc_register_fd(struct bsc_fd *fd);
 void bsc_unregister_fd(struct bsc_fd *fd);
-int bsc_select_main(void);
+int bsc_select_main(int polling);
 #endif /* _BSC_SELECT_H */
diff --git a/src/bs11_config.c b/src/bs11_config.c
index 3da0c528d..57ed9023e 100644
--- a/src/bs11_config.c
+++ b/src/bs11_config.c
@@ -790,7 +790,7 @@ int main(int argc, char **argv)
 	status_timer.cb = status_timer_cb;
 
 	while (1) {
-		bsc_select_main();
+		bsc_select_main(0);
 	}
 
 	abis_nm_bs11_factory_logon(g_bts, 0);
diff --git a/src/bsc_hack.c b/src/bsc_hack.c
index cd3ca4144..797c62783 100644
--- a/src/bsc_hack.c
+++ b/src/bsc_hack.c
@@ -1123,6 +1123,6 @@ int main(int argc, char **argv)
 	signal(SIGABRT, &signal_handler);
 
 	while (1) {
-		bsc_select_main();
+		bsc_select_main(0);
 	}
 }
diff --git a/src/ipaccess-config.c b/src/ipaccess-config.c
index 964d6186c..b74e46e89 100644
--- a/src/ipaccess-config.c
+++ b/src/ipaccess-config.c
@@ -188,7 +188,7 @@ int main(int argc, char **argv)
 	}
 	
 	while (1) {
-		rc = bsc_select_main();
+		rc = bsc_select_main(0);
 		if (rc < 0)
 			exit(3);
 	}
diff --git a/src/ipaccess-find.c b/src/ipaccess-find.c
index 32f42e904..b3e9814a9 100644
--- a/src/ipaccess-find.c
+++ b/src/ipaccess-find.c
@@ -170,7 +170,7 @@ int main(int argc, char **argv)
 	printf("Trying to find ip.access BTS by broadcast UDP...\n");
 
 	while (1) {
-		rc = bsc_select_main();
+		rc = bsc_select_main(0);
 		if (rc < 0)
 			exit(3);
 	}
diff --git a/src/select.c b/src/select.c
index 157e23500..11b7e6b49 100644
--- a/src/select.c
+++ b/src/select.c
@@ -53,11 +53,12 @@ void bsc_unregister_fd(struct bsc_fd *fd)
 	llist_del(&fd->list);
 }
 
-int bsc_select_main()
+int bsc_select_main(int polling)
 {
 	struct bsc_fd *ufd, *tmp;
 	fd_set readset, writeset, exceptset;
-	int i;
+	int work = 0, rc;
+	struct timeval no_time = {0, 0};
 
 	FD_ZERO(&readset);
 	FD_ZERO(&writeset);
@@ -75,10 +76,11 @@ int bsc_select_main()
 			FD_SET(ufd->fd, &exceptset);
 	}
 
-	bsc_prepare_timers();
-	i = select(maxfd+1, &readset, &writeset, &exceptset, bsc_nearest_timer());
-	if (i < 0)
-		return i;
+	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();
@@ -96,8 +98,10 @@ int bsc_select_main()
 		if (FD_ISSET(ufd->fd, &exceptset))
 			flags |= BSC_FD_EXCEPT;
 
-		if (flags)
+		if (flags) {
+			work = 1;
 			ufd->cb(ufd, flags);
+		}
 	}
-	return i;
+	return work;
 }
diff --git a/tests/timer/timer_test.c b/tests/timer/timer_test.c
index 339404e4b..26fcbc938 100644
--- a/tests/timer/timer_test.c
+++ b/tests/timer/timer_test.c
@@ -65,6 +65,6 @@ int main(int argc, char** argv)
     bsc_schedule_timer(&timer_three, 4, 0);
 
     while (1) {
-        bsc_select_main();
+        bsc_select_main(0);
     }
 }