[PATCH libevdev 4/6] Drop hardcoded MAX_SLOTS in favour of pre-allocated memory
Peter Hutterer
peter.hutterer at who-t.net
Tue Apr 1 19:17:27 PDT 2014
We can't allocate in sync_mt_state since it may be called in the signal
handler. So pre-allocate based on the device's number of slots, store that in
the libevdev struct and use it for the sync process.
This fixes a remaining bug with the handling of ABS_MT_TRACKING_ID. If a
device had > MAX_SLOTS and a slot above that limit would start or stop during
a SYN_DROPPED event, the slot would not be synced, and a subsequent touch in
that slot may double-terminate or double-open a touchpoint in the client.
For the effects of that see
commit 41334b5b40cd5456f5f584b55d8888aaafa1f26e
Author: Peter Hutterer <peter.hutterer at who-t.net>
Date: Thu Mar 6 11:54:00 2014 +1000
If the tracking ID changes during SYN_DROPPED, terminate the touch first
Signed-off-by: Peter Hutterer <peter.hutterer at who-t.net>
---
libevdev/libevdev-int.h | 15 ++++++-
libevdev/libevdev.c | 53 +++++++++++++++-------
libevdev/libevdev.h | 5 ---
test/test-libevdev-events.c | 107 --------------------------------------------
4 files changed, 52 insertions(+), 128 deletions(-)
diff --git a/libevdev/libevdev-int.h b/libevdev/libevdev-int.h
index 5ff6026..98c75ce 100644
--- a/libevdev/libevdev-int.h
+++ b/libevdev/libevdev-int.h
@@ -32,7 +32,6 @@
#include "libevdev-util.h"
#define MAX_NAME 256
-#define MAX_SLOTS 60
#define ABS_MT_MIN ABS_MT_SLOT
#define ABS_MT_MAX ABS_MT_TOOL_Y
#define ABS_MT_CNT (ABS_MT_MAX - ABS_MT_MIN + 1)
@@ -57,6 +56,11 @@ enum SyncState {
SYNC_IN_PROGRESS,
};
+struct mt_sync_state {
+ int code;
+ int val[];
+};
+
struct libevdev {
int fd;
bool initialized;
@@ -94,6 +98,15 @@ struct libevdev {
size_t queue_nsync; /**< number of sync events */
struct timeval last_event_time;
+
+ struct {
+ struct mt_sync_state *mt_state;
+ size_t mt_state_sz; /* in bytes */
+ unsigned long *slot_update;
+ size_t slot_update_sz; /* in bytes */
+ unsigned long *tracking_id_changes;
+ size_t tracking_id_changes_sz; /* in bytes */
+ } mt_sync;
};
struct logdata {
diff --git a/libevdev/libevdev.c b/libevdev/libevdev.c
index e2070d4..ab67002 100644
--- a/libevdev/libevdev.c
+++ b/libevdev/libevdev.c
@@ -152,6 +152,9 @@ libevdev_reset(struct libevdev *dev)
free(dev->phys);
free(dev->uniq);
free(dev->mt_slot_vals);
+ free(dev->mt_sync.mt_state);
+ free(dev->mt_sync.tracking_id_changes);
+ free(dev->mt_sync.slot_update);
memset(dev, 0, sizeof(*dev));
dev->fd = -1;
dev->initialized = false;
@@ -389,8 +392,27 @@ libevdev_set_fd(struct libevdev* dev, int fd)
goto out;
}
dev->current_slot = abs_info.value;
+
+ dev->mt_sync.mt_state_sz = sizeof(*dev->mt_sync.mt_state) +
+ (dev->num_slots) * sizeof(int);
+ dev->mt_sync.mt_state = calloc(1, dev->mt_sync.mt_state_sz);
+ if (!dev->mt_sync.mt_state) {
+ rc = -ENOMEM;
+ goto out;
+ }
+
+ dev->mt_sync.tracking_id_changes_sz = NLONGS(dev->num_slots) * sizeof(long);
+ dev->mt_sync.tracking_id_changes = malloc(dev->mt_sync.tracking_id_changes_sz);
+
+ dev->mt_sync.slot_update_sz = NLONGS(dev->num_slots * ABS_MT_CNT) * sizeof(long);
+ dev->mt_sync.slot_update = malloc(dev->mt_sync.slot_update_sz);
+
+ if (!dev->mt_sync.tracking_id_changes ||
+ !dev->mt_sync.slot_update) {
+ rc = -ENOMEM;
+ goto out;
+ }
}
-
}
}
@@ -556,14 +578,15 @@ sync_mt_state(struct libevdev *dev, int create_events)
int axis, slot;
int ioctl_success = 0;
int last_reported_slot = 0;
- struct mt_state {
- int code;
- int val[MAX_SLOTS];
- } mt_state;
- unsigned long slot_update[NLONGS(MAX_SLOTS * ABS_MT_CNT)] = {0};
- unsigned long tracking_id_changes[NLONGS(MAX_SLOTS)] = {0};
+ struct mt_sync_state *mt_state = dev->mt_sync.mt_state;
+ unsigned long *slot_update = dev->mt_sync.slot_update;
+ unsigned long *tracking_id_changes = dev->mt_sync.tracking_id_changes;
int need_tracking_id_changes = 0;
+ memset(dev->mt_sync.slot_update, 0, dev->mt_sync.slot_update_sz);
+ memset(dev->mt_sync.tracking_id_changes, 0,
+ dev->mt_sync.tracking_id_changes_sz);
+
#define AXISBIT(_slot, _axis) (_slot * ABS_MT_CNT + _axis - ABS_MT_MIN)
for (axis = ABS_MT_MIN; axis <= ABS_MT_MAX; axis++) {
@@ -573,8 +596,8 @@ sync_mt_state(struct libevdev *dev, int create_events)
if (!libevdev_has_event_code(dev, EV_ABS, axis))
continue;
- mt_state.code = axis;
- rc = ioctl(dev->fd, EVIOCGMTSLOTS(sizeof(struct mt_state)), &mt_state);
+ mt_state->code = axis;
+ rc = ioctl(dev->fd, EVIOCGMTSLOTS(dev->mt_sync.mt_state_sz), mt_state);
if (rc < 0) {
/* if the first ioctl fails with -EINVAL, chances are the kernel
doesn't support the ioctl. Simply continue */
@@ -586,19 +609,19 @@ sync_mt_state(struct libevdev *dev, int create_events)
if (ioctl_success == 0)
ioctl_success = 1;
- for (slot = 0; slot < min(dev->num_slots, MAX_SLOTS); slot++) {
+ for (slot = 0; slot < dev->num_slots; slot++) {
- if (*slot_value(dev, slot, axis) == mt_state.val[slot])
+ if (*slot_value(dev, slot, axis) == mt_state->val[slot])
continue;
if (axis == ABS_MT_TRACKING_ID &&
*slot_value(dev, slot, axis) != -1 &&
- mt_state.val[slot] != -1) {
+ mt_state->val[slot] != -1) {
set_bit(tracking_id_changes, slot);
need_tracking_id_changes = 1;
}
- *slot_value(dev, slot, axis) = mt_state.val[slot];
+ *slot_value(dev, slot, axis) = mt_state->val[slot];
set_bit(slot_update, AXISBIT(slot, axis));
/* note that this slot has updates */
@@ -615,7 +638,7 @@ sync_mt_state(struct libevdev *dev, int create_events)
}
if (need_tracking_id_changes) {
- for (slot = 0; slot < min(dev->num_slots, MAX_SLOTS); slot++) {
+ for (slot = 0; slot < dev->num_slots; slot++) {
if (!bit_is_set(tracking_id_changes, slot))
continue;
@@ -631,7 +654,7 @@ sync_mt_state(struct libevdev *dev, int create_events)
init_event(dev, ev, EV_SYN, SYN_REPORT, 0);
}
- for (slot = 0; slot < min(dev->num_slots, MAX_SLOTS); slot++) {
+ for (slot = 0; slot < dev->num_slots; slot++) {
if (!bit_is_set(slot_update, AXISBIT(slot, ABS_MT_SLOT)))
continue;
diff --git a/libevdev/libevdev.h b/libevdev/libevdev.h
index 77ee08a..aa7b90d 100644
--- a/libevdev/libevdev.h
+++ b/libevdev/libevdev.h
@@ -914,11 +914,6 @@ enum libevdev_read_status {
* have been synced. For more details on what libevdev does to sync after a
* SYN_DROPPED event, see @ref syn_dropped.
*
- * @note The implementation of libevdev limits the maximum number of slots
- * that can be synched. If your device exceeds the number of slots
- * (currently 60), slot indices equal and above this maximum are ignored and
- * their value will not update until the next event in that slot.
- *
* If a device needs to be synced by the caller but the caller does not call
* with the @ref LIBEVDEV_READ_FLAG_SYNC flag set, all events from the diff are
* dropped after libevdev updates its internal state and event processing
diff --git a/test/test-libevdev-events.c b/test/test-libevdev-events.c
index 412db71..fda7617 100644
--- a/test/test-libevdev-events.c
+++ b/test/test-libevdev-events.c
@@ -30,8 +30,6 @@
#include "test-common.h"
-#define MAX_SLOTS 60 /* as in libevdev-int.h */
-
START_TEST(test_next_event)
{
struct uinput_device* uidev;
@@ -662,110 +660,6 @@ START_TEST(test_syn_delta_mt_reset_slot)
}
END_TEST
-START_TEST(test_syn_delta_mt_too_many)
-{
- struct uinput_device* uidev;
- struct libevdev *dev;
- int rc;
- struct input_event ev;
- struct input_absinfo abs[6];
- int i;
- int num_slots = MAX_SLOTS + 20;
-
- memset(abs, 0, sizeof(abs));
- abs[0].value = ABS_X;
- abs[0].maximum = 1000;
- abs[1].value = ABS_MT_POSITION_X;
- abs[1].maximum = 1000;
-
- abs[2].value = ABS_Y;
- abs[2].maximum = 1000;
- abs[3].value = ABS_MT_POSITION_Y;
- abs[3].maximum = 1000;
-
- abs[4].value = ABS_MT_SLOT;
- abs[4].maximum = num_slots;
- abs[5].value = ABS_MT_TOOL_Y;
- abs[5].maximum = 500;
-
- rc = test_create_abs_device(&uidev, &dev,
- 6, abs,
- EV_SYN, SYN_REPORT,
- -1);
- ck_assert_msg(rc == 0, "Failed to create device: %s", strerror(-rc));
-
- for (i = num_slots; i >= 0; i--) {
- uinput_device_event(uidev, EV_ABS, ABS_MT_SLOT, i);
- uinput_device_event(uidev, EV_ABS, ABS_X, 100 + i);
- uinput_device_event(uidev, EV_ABS, ABS_Y, 500 + i);
- uinput_device_event(uidev, EV_ABS, ABS_MT_POSITION_X, 100 + i);
- uinput_device_event(uidev, EV_ABS, ABS_MT_POSITION_Y, 500 + i);
- uinput_device_event(uidev, EV_ABS, ABS_MT_TOOL_Y, 1 + i);
- uinput_device_event(uidev, EV_SYN, SYN_REPORT, 0);
- }
-
- /* drain the fd, so libevdev_next_event doesn't pick up any events
- before the FORCE_SYNC */
- do {
- rc = read(libevdev_get_fd(dev), &ev, sizeof(ev));
- } while (rc > 0);
-
- rc = libevdev_next_event(dev, LIBEVDEV_READ_FLAG_FORCE_SYNC, &ev);
- ck_assert_int_eq(rc, LIBEVDEV_READ_STATUS_SYNC);
-
- i = 0;
- while (i < num_slots) {
- int slot;
-
- rc = libevdev_next_event(dev, LIBEVDEV_READ_FLAG_SYNC, &ev);
- ck_assert_int_eq(rc, LIBEVDEV_READ_STATUS_SYNC);
-
- if (libevdev_event_is_code(&ev, EV_SYN, SYN_REPORT))
- break;
-
- if (libevdev_event_is_code(&ev, EV_ABS, ABS_X) ||
- libevdev_event_is_code(&ev, EV_ABS, ABS_Y))
- continue;
-
- ck_assert_int_eq(ev.type, EV_ABS);
- ck_assert_int_eq(ev.code, ABS_MT_SLOT);
- slot = ev.value;
- ck_assert_int_lt(slot, MAX_SLOTS);
-
- rc = libevdev_next_event(dev, LIBEVDEV_READ_FLAG_SYNC, &ev);
-
- /* last MT_SLOT event is on its own */
- if (libevdev_event_is_code(&ev, EV_SYN, SYN_REPORT))
- break;
-
- ck_assert_int_eq(rc, LIBEVDEV_READ_STATUS_SYNC);
- ck_assert_int_eq(ev.type, EV_ABS);
- ck_assert_int_eq(ev.code, ABS_MT_POSITION_X);
- ck_assert_int_eq(ev.value, 100 + slot);
- rc = libevdev_next_event(dev, LIBEVDEV_READ_FLAG_SYNC, &ev);
- ck_assert_int_eq(rc, LIBEVDEV_READ_STATUS_SYNC);
- ck_assert_int_eq(ev.type, EV_ABS);
- ck_assert_int_eq(ev.code, ABS_MT_POSITION_Y);
- ck_assert_int_eq(ev.value, 500 + slot);
- rc = libevdev_next_event(dev, LIBEVDEV_READ_FLAG_SYNC, &ev);
- ck_assert_int_eq(rc, LIBEVDEV_READ_STATUS_SYNC);
- ck_assert_int_eq(ev.type, EV_ABS);
- ck_assert_int_eq(ev.code, ABS_MT_TOOL_Y);
- ck_assert_int_eq(ev.value, 1 + slot);
-
- i++;
- }
-
- /* we expect eactly MAX_SLOTS to be synced */
- ck_assert_int_eq(i, MAX_SLOTS);
- rc = libevdev_next_event(dev, LIBEVDEV_READ_FLAG_SYNC, &ev);
- ck_assert_int_eq(rc, -EAGAIN);
-
- uinput_device_free(uidev);
- libevdev_free(dev);
-}
-END_TEST
-
START_TEST(test_syn_delta_led)
{
struct uinput_device* uidev;
@@ -1806,7 +1700,6 @@ libevdev_events(void)
tcase_add_test(tc, test_syn_delta_button);
tcase_add_test(tc, test_syn_delta_abs);
tcase_add_test(tc, test_syn_delta_mt);
- tcase_add_test(tc, test_syn_delta_mt_too_many);
tcase_add_test(tc, test_syn_delta_mt_reset_slot);
tcase_add_test(tc, test_syn_delta_led);
tcase_add_test(tc, test_syn_delta_sw);
--
1.9.0
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