Change internal timestamps to uint64_t to properly deal with wrapping

We store timestamps in ms since system boot (CLOCK_MONOTONIC). This will wrap
after circa 50 days.

I've considered making our code wrapping safe, but that won't work. We also
use our internal timestamps to program timer-fds for timeouts. And we store
ms in a single integer but the kernel uses 2 integers, one for seconds and
one for usec/nanosec. So at 32 bits our ms containing integer will wrap
in 50 days, while the kernels seconds storing integer lasts a lot longer.
So when we wrap our ms timestamps, we will be programming the timer-fds
with a seconds value in the past.

So change all our internal timestamps to uint64_t to avoid the wrapping
when programming the timer-fds. Note that we move from 64-bit timestamps to
32-bit timestamps when calling the foo_notify_bar functions from
libinput-private.h. Having 64 bit timestamps has no use past this point,
since the wayland input protocol uses 32 bit timestamps (and clients will
have to deal with wrapping).

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Reviewed-by: Peter Hutterer <peter.hutterer@who-t.net>

1 files changed, 7 insertions, 7 deletions

diff --git a/src/evdev-mt-touchpad.h b/src/evdev-mt-touchpad.h
index 41f9daf7..41e3ca43 100644
--- a/src/evdev-mt-touchpad.h
+++ b/src/evdev-mt-touchpad.h
@@ -97,7 +97,7 @@ struct tp_touch {
 	bool is_pointer;			/* the pointer-controlling touch */
 	int32_t x;
 	int32_t y;
-	uint32_t millis;
+	uint64_t millis;
 
 	struct {
 		struct tp_motion samples[TOUCHPAD_HISTORY_LENGTH];
@@ -125,7 +125,7 @@ struct tp_touch {
 		enum button_state state;
 		/* We use button_event here so we can use == on events */
 		enum button_event curr;
-		uint32_t timeout;
+		uint64_t timeout;
 	} button;
 };
 
@@ -204,10 +204,10 @@ void
 tp_set_pointer(struct tp_dispatch *tp, struct tp_touch *t);
 
 int
-tp_tap_handle_state(struct tp_dispatch *tp, uint32_t time);
+tp_tap_handle_state(struct tp_dispatch *tp, uint64_t time);
 
 unsigned int
-tp_tap_handle_timeout(struct tp_dispatch *tp, uint32_t time);
+tp_tap_handle_timeout(struct tp_dispatch *tp, uint64_t time);
 
 int
 tp_init_tap(struct tp_dispatch *tp);
@@ -224,13 +224,13 @@ tp_destroy_buttons(struct tp_dispatch *tp);
 int
 tp_process_button(struct tp_dispatch *tp,
 		  const struct input_event *e,
-		  uint32_t time);
+		  uint64_t time);
 
 int
-tp_post_button_events(struct tp_dispatch *tp, uint32_t time);
+tp_post_button_events(struct tp_dispatch *tp, uint64_t time);
 
 int
-tp_button_handle_state(struct tp_dispatch *tp, uint32_t time);
+tp_button_handle_state(struct tp_dispatch *tp, uint64_t time);
 
 int
 tp_button_touch_active(struct tp_dispatch *tp, struct tp_touch *t);