commit ae0f99084d890df476e681ad3b85925ee877715f
author Siarhei Vishniakou <svv@google.com> Mon Sep 14 19:23:31 2020 -0500
committer Siarhei Vishniakou <svv@google.com> Tue Sep 22 15:05:02 2020 +0000
tree 85fcf2bbb1f0e2ed37613d2b300cb231a03ee5af
parent b2d6a712e8fbe7cc81696ed38809689727d30ec6

Use std::vector instead of VLA for addMovement

Currently, VLA is used to send data to 'addMovement' in VelocityTracker.
Use std::vector instead. This also helps assert against the number of
pointers present in the idBits.

Bug: 167946721
Test: atest libinput_tests
Change-Id: Ie8aabafe9a407a2b07d3edef4d1fa312510ccdba

libs/input/VelocityTracker.cpp

diff --git a/libs/input/VelocityTracker.cpp b/libs/input/VelocityTracker.cpp
index 7c28ac5..d74c520 100644
--- a/libs/input/VelocityTracker.cpp
+++ b/libs/input/VelocityTracker.cpp
@@ -193,7 +193,11 @@
     mStrategy->clearPointers(idBits);
 }
 
-void VelocityTracker::addMovement(nsecs_t eventTime, BitSet32 idBits, const Position* positions) {
+void VelocityTracker::addMovement(nsecs_t eventTime, BitSet32 idBits,
+                                  const std::vector<VelocityTracker::Position>& positions) {
+    LOG_ALWAYS_FATAL_IF(idBits.count() != positions.size(),
+                        "Mismatching number of pointers, idBits=%" PRIu32 ", positions=%zu",
+                        idBits.count(), positions.size());
     while (idBits.count() > MAX_POINTERS) {
         idBits.clearLastMarkedBit();
     }
@@ -286,7 +290,8 @@
     }
 
     nsecs_t eventTime;
-    Position positions[pointerCount];
+    std::vector<Position> positions;
+    positions.resize(pointerCount);
 
     size_t historySize = event->getHistorySize();
     for (size_t h = 0; h < historySize; h++) {
@@ -346,8 +351,9 @@
     mMovements[mIndex].idBits = remainingIdBits;
 }
 
-void LeastSquaresVelocityTrackerStrategy::addMovement(nsecs_t eventTime, BitSet32 idBits,
-        const VelocityTracker::Position* positions) {
+void LeastSquaresVelocityTrackerStrategy::addMovement(
+        nsecs_t eventTime, BitSet32 idBits,
+        const std::vector<VelocityTracker::Position>& positions) {
     if (mMovements[mIndex].eventTime != eventTime) {
         // When ACTION_POINTER_DOWN happens, we will first receive ACTION_MOVE with the coordinates
         // of the existing pointers, and then ACTION_POINTER_DOWN with the coordinates that include
@@ -758,8 +764,9 @@
     mPointerIdBits.value &= ~idBits.value;
 }
 
-void IntegratingVelocityTrackerStrategy::addMovement(nsecs_t eventTime, BitSet32 idBits,
-        const VelocityTracker::Position* positions) {
+void IntegratingVelocityTrackerStrategy::addMovement(
+        nsecs_t eventTime, BitSet32 idBits,
+        const std::vector<VelocityTracker::Position>& positions) {
     uint32_t index = 0;
     for (BitSet32 iterIdBits(idBits); !iterIdBits.isEmpty();) {
         uint32_t id = iterIdBits.clearFirstMarkedBit();
@@ -876,8 +883,9 @@
     mMovements[mIndex].idBits = remainingIdBits;
 }
 
-void LegacyVelocityTrackerStrategy::addMovement(nsecs_t eventTime, BitSet32 idBits,
-        const VelocityTracker::Position* positions) {
+void LegacyVelocityTrackerStrategy::addMovement(
+        nsecs_t eventTime, BitSet32 idBits,
+        const std::vector<VelocityTracker::Position>& positions) {
     if (++mIndex == HISTORY_SIZE) {
         mIndex = 0;
     }
@@ -990,8 +998,9 @@
     mMovements[mIndex].idBits = remainingIdBits;
 }
 
-void ImpulseVelocityTrackerStrategy::addMovement(nsecs_t eventTime, BitSet32 idBits,
-        const VelocityTracker::Position* positions) {
+void ImpulseVelocityTrackerStrategy::addMovement(
+        nsecs_t eventTime, BitSet32 idBits,
+        const std::vector<VelocityTracker::Position>& positions) {
     if (mMovements[mIndex].eventTime != eventTime) {
         // When ACTION_POINTER_DOWN happens, we will first receive ACTION_MOVE with the coordinates
         // of the existing pointers, and then ACTION_POINTER_DOWN with the coordinates that include