[input] Use a single select call for all drivers

For drivers that support it. Polling is still supported and forces the
select timeout to 0 if any driver requires polling. For now, the default
timeout when all drivers use select is 10ms.

include/QF/input.h

@@ -45,6 +45,9 @@ typedef struct in_buttoninfo_s {
 } in_buttoninfo_t;
 
 #ifndef __QFCC__
+
+#include <sys/select.h>
+
 typedef struct {
 	vec3_t angles;
 	vec3_t position;
@@ -53,7 +56,14 @@ typedef struct {
 typedef struct in_driver_s {
 	void (*init) (void *data);
 	void (*shutdown) (void *data);
+
+	// The driver must provide either both or none of add_select and
+	// chec_select.
+	void (*add_select) (fd_set *fdset, int *maxfd, void *data);
+	void (*check_select) (fd_set *fdset, void *data);
+	// Generally musually exclusive with add_select/check_select
 	void (*process_events) (void *data);
+
 	void (*clear_states) (void *data);
 	void (*grab_input) (void *data, int grab);
 

include/evdev/inputlib.h

@@ -44,6 +44,8 @@ typedef struct device_s {
 	void      (*button_event) (button_t *button, void *data);
 } device_t;
 
+void inputlib_add_select (fd_set *fdset, int *maxfd);
+void inputlib_check_select (fd_set *fdset);
 int inputlib_check_input (void);
 void inputlib_close (void);
 int inputlib_init (void (*dev_add) (device_t *), void (*dev_rem) (device_t *));

libs/input/evdev/inputlib.c

@@ -309,6 +309,37 @@ read_device_input (device_t *dev)
 	}
 }
 
+void
+inputlib_add_select (fd_set *fdset, int *maxfd)
+{
+	inputlib_hotplug_add_select (fdset, maxfd);
+
+	for (device_t *dev = devices; dev; dev = dev->next) {
+		if (dev->fd < 0) {
+			continue;
+		}
+		FD_SET (dev->fd, fdset);
+		if (dev->fd > *maxfd) {
+			*maxfd = dev->fd;
+		}
+	}
+}
+
+void
+inputlib_check_select (fd_set *fdset)
+{
+	inputlib_hotplug_check_select (fdset);
+
+	for (device_t *dev = devices; dev; dev = dev->next) {
+		if (dev->fd < 0) {
+			continue;
+		}
+		if (FD_ISSET (dev->fd, fdset)) {
+			read_device_input (dev);
+		}
+	}
+}
+
 int
 inputlib_check_input (void)
 {
@@ -317,24 +348,13 @@ inputlib_check_input (void)
 	struct timeval *timeout = &_timeout;
 	int         res;
 	int         maxfd = -1;
-	device_t   *dev;
 
 	_timeout.tv_sec = 0;
 	_timeout.tv_usec = 0;
 
 	FD_ZERO (&fdset);
 
-	inputlib_hotplug_add_select (&fdset, &maxfd);
-
-	for (dev = devices; dev; dev = dev->next) {
-		if (dev->fd < 0) {
-			continue;
-		}
-		FD_SET (dev->fd, &fdset);
-		if (dev->fd > maxfd) {
-			maxfd = dev->fd;
-		}
-	}
+	inputlib_add_select (&fdset, &maxfd);
 	if (maxfd < 0) {
 		return 0;
 	}
@@ -343,16 +363,7 @@ inputlib_check_input (void)
 		return 0;
 	}
 
-	inputlib_hotplug_check_select (&fdset);
-
-	for (dev = devices; dev; dev = dev->next) {
-		if (dev->fd < 0) {
-			continue;
-		}
-		if (FD_ISSET (dev->fd, &fdset)) {
-			read_device_input (dev);
-		}
-	}
+	inputlib_check_select (&fdset);
 	return 1;
 }
 

libs/input/in_common.c

@@ -77,6 +77,7 @@ cvar_t     *in_mouse_amp;
 cvar_t     *in_mouse_pre_amp;
 cvar_t     *lookstrafe;
 
+int64_t     in_timeout = 10000;//10ms default timeout
 kbutton_t   in_mlook, in_klook;
 kbutton_t   in_strafe;
 kbutton_t   in_speed;
@@ -265,9 +266,29 @@ IN_UpdateGrab (cvar_t *var)		// called from context_*.c
 void
 IN_ProcessEvents (void)
 {
+	fd_set      fdset;
+	int         maxfd = -1;
+	int64_t     timeout = in_timeout;
+
+	FD_ZERO (&fdset);
 	for (size_t i = 0; i < in_drivers.size; i++) {
 		in_regdriver_t *rd = &in_drivers.a[i];
-		rd->driver.process_events (rd->data);
+		if (rd->driver.add_select) {
+			rd->driver.add_select (&fdset, &maxfd, rd->data);
+		}
+		if (rd->driver.process_events) {
+			rd->driver.process_events (rd->data);
+			// if a driver can't use select, then we can't block in select
+			timeout = 0;
+		}
+	}
+	if (maxfd >= 0 && Sys_Select (maxfd, &fdset, timeout) > 0) {
+		for (size_t i = 0; i < in_drivers.size; i++) {
+			in_regdriver_t *rd = &in_drivers.a[i];
+			if (rd->driver.check_select) {
+				rd->driver.check_select (&fdset, rd->data);
+			}
+		}
 	}
 }
 

libs/input/in_evdev.c

@@ -62,10 +62,15 @@ in_evdev_keydest_callback (keydest_t key_dest, void *data)
 }
 
 static void
-in_evdev_process_events (void *data)
+in_evdev_add_select (fd_set *fdset, int *maxfd, void *data)
 {
-	if (inputlib_check_input ()) {
-	}
+	inputlib_add_select (fdset, maxfd);
+}
+
+static void
+in_evdev_check_select (fd_set *fdset, void *data)
+{
+	inputlib_check_select (fdset);
 }
 
 static void
@@ -223,7 +228,8 @@ in_evdev_button_info (void *data, void *device, in_buttoninfo_t *buttons,
 static in_driver_t in_evdev_driver = {
 	.init = in_evdev_init,
 	.shutdown = in_evdev_shutdown,
-	.process_events = in_evdev_process_events,
+	.add_select = in_evdev_add_select,
+	.check_select = in_evdev_check_select,
 	.clear_states = in_evdev_clear_states,
 
 	.axis_info = in_evdev_axis_info,

ruamoko/qwaq/builtins/input.c

@@ -464,8 +464,18 @@ term_shutdown (void *_res)
 {
 }
 
+#define FD 0
 static void
-term_process_events (void *_res)
+term_add_select (fd_set *fdset, int *maxfd, void *_res)
+{
+	FD_SET (FD, fdset);
+	if (*maxfd < FD) {
+		*maxfd = FD;
+	}
+}
+
+static void
+term_check_select (fd_set *fdset, void *_res)
 {
 	qwaq_input_resources_t *res = _res;
 	char        buf[256];
@@ -482,7 +492,7 @@ term_process_events (void *_res)
 		resize_event (res);
 	}
 #endif
-	while (Sys_CheckInput (1, -1)) {
+	if (FD_ISSET (FD, fdset)) {
 		len = read(0, buf, sizeof (buf));
 		for (int i = 0; i < len; i++) {
 			process_char (res, buf[i]);
@@ -493,7 +503,8 @@ term_process_events (void *_res)
 static in_driver_t term_driver = {
 	.init = term_init,
 	.shutdown = term_shutdown,
-	.process_events = term_process_events,
+	.add_select = term_add_select,
+	.check_select = term_check_select,
 };
 static int term_driver_handle;