Add int range for touchscreen pointer id.

We are validating touch point id from ag/21078609, it's necessary to
enforce this from the API to prevent silent failures.

Test: atest VirtualInputDeviceConfigTest VirtualTouchscreenTest
Bug: 259554911

Change-Id: Ica8a3b5cc46517e6773c8c3a9d46e5606c63c00d
Merged-In: Ica8a3b5cc46517e6773c8c3a9d46e5606c63c00d

2 files changed, 15 insertions, 2 deletions

diff --git a/core/api/system-current.txt b/core/api/system-current.txt
index 6581c421f970..664961fa8346 100644
--- a/core/api/system-current.txt
+++ b/core/api/system-current.txt
@@ -5117,7 +5117,7 @@ package android.hardware.input {
     method @NonNull public android.hardware.input.VirtualTouchEvent build();
     method @NonNull public android.hardware.input.VirtualTouchEvent.Builder setAction(int);
     method @NonNull public android.hardware.input.VirtualTouchEvent.Builder setMajorAxisSize(@FloatRange(from=0.0f) float);
-    method @NonNull public android.hardware.input.VirtualTouchEvent.Builder setPointerId(int);
+    method @NonNull public android.hardware.input.VirtualTouchEvent.Builder setPointerId(@IntRange(from=0, to=0x10 - 1) int);
     method @NonNull public android.hardware.input.VirtualTouchEvent.Builder setPressure(@FloatRange(from=0.0f) float);
     method @NonNull public android.hardware.input.VirtualTouchEvent.Builder setToolType(int);
     method @NonNull public android.hardware.input.VirtualTouchEvent.Builder setX(float);
diff --git a/core/java/android/hardware/input/VirtualTouchEvent.java b/core/java/android/hardware/input/VirtualTouchEvent.java
index 9b1e6e84a022..a2bb382e9950 100644
--- a/core/java/android/hardware/input/VirtualTouchEvent.java
+++ b/core/java/android/hardware/input/VirtualTouchEvent.java
@@ -18,6 +18,7 @@ package android.hardware.input;
 
 import android.annotation.FloatRange;
 import android.annotation.IntDef;
+import android.annotation.IntRange;
 import android.annotation.NonNull;
 import android.annotation.SystemApi;
 import android.os.Parcel;
@@ -82,6 +83,10 @@ public final class VirtualTouchEvent implements Parcelable {
     @Retention(RetentionPolicy.SOURCE)
     public @interface Action {}
 
+    // The maximum number of pointers that can be touching the screen at once. (See MAX_POINTERS
+    // in frameworks/native/include/input/Input.h)
+    private static final int MAX_POINTERS = 16;
+
     private final int mPointerId;
     private final @ToolType int mToolType;
     private final @Action int mAction;
@@ -214,9 +219,17 @@ public final class VirtualTouchEvent implements Parcelable {
         /**
          * Sets the pointer id of the event.
          *
+         * <p>A Valid pointer id need to be in the range of 0 to 15.
+         *
          * @return this builder, to allow for chaining of calls
          */
-        public @NonNull Builder setPointerId(int pointerId) {
+        public @NonNull Builder setPointerId(
+                @IntRange(from = 0, to = MAX_POINTERS - 1) int pointerId) {
+            if (pointerId < 0 || pointerId > 15) {
+                throw new IllegalArgumentException(
+                        "The pointer id must be in the range 0 - " + (MAX_POINTERS - 1)
+                                + "inclusive, but was: " + pointerId);
+            }
             mPointerId = pointerId;
             return this;
         }