From 724b2d27d49da23cf4cd9b5de921421eb4cc5de2 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Maciej=20=C5=BBenczykowski?= <maze@google.com>
Date: Tue, 29 Jul 2025 13:30:43 -0700
Subject: [PATCH] make Struct expose a new parse method that takes a raw byte
 array
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Test: TreeHugger
Flag: EXEMPT mainline
Signed-off-by: Maciej Żenczykowski <maze@google.com>
Change-Id: Ifdfc93e0c35df58a983beb30da546db7a0876398
---
 .../device/com/android/net/module/util/BpfMap.java    | 10 ++--------
 .../device/com/android/net/module/util/Struct.java    | 11 +++++++++++
 2 files changed, 13 insertions(+), 8 deletions(-)

diff --git a/staticlibs/device/com/android/net/module/util/BpfMap.java b/staticlibs/device/com/android/net/module/util/BpfMap.java
index 0fbc25de7b..7dd09e00e6 100644
--- a/staticlibs/device/com/android/net/module/util/BpfMap.java
+++ b/staticlibs/device/com/android/net/module/util/BpfMap.java
@@ -28,8 +28,6 @@ import androidx.annotation.NonNull;
 import androidx.annotation.Nullable;
 import androidx.annotation.RequiresApi;
 
-import java.nio.ByteBuffer;
-import java.nio.ByteOrder;
 import java.util.NoSuchElementException;
 import java.util.Objects;
 import java.util.concurrent.ConcurrentHashMap;
@@ -217,9 +215,7 @@ public class BpfMap<K extends Struct, V extends Struct> implements IBpfMap<K, V>
                                  key == null ? null : key.writeToBytes(),
                                  rawKey)) return null;
 
-        final ByteBuffer buffer = ByteBuffer.wrap(rawKey);
-        buffer.order(ByteOrder.nativeOrder());
-        return Struct.parse(mKeyClass, buffer);
+        return Struct.parse(mKeyClass, rawKey);
     }
 
     /**
@@ -257,9 +253,7 @@ public class BpfMap<K extends Struct, V extends Struct> implements IBpfMap<K, V>
         byte[] rawValue = new byte[mValueSize];
         if (!nativeFindMapEntry(mMapFd.getFd(), key.writeToBytes(), rawValue)) return null;
 
-        final ByteBuffer buffer = ByteBuffer.wrap(rawValue);
-        buffer.order(ByteOrder.nativeOrder());
-        return Struct.parse(mValueClass, buffer);
+        return Struct.parse(mValueClass, rawValue);
     }
 
     /** Synchronize Kernel RCU */
diff --git a/staticlibs/device/com/android/net/module/util/Struct.java b/staticlibs/device/com/android/net/module/util/Struct.java
index 006642b26f..ccf3957e88 100644
--- a/staticlibs/device/com/android/net/module/util/Struct.java
+++ b/staticlibs/device/com/android/net/module/util/Struct.java
@@ -654,6 +654,17 @@ public class Struct {
         }
     }
 
+    /**
+     * Parse raw data from a byte array according to the pre-defined annotation rule and return
+     * the type-variable object which is subclass of Struct class.
+     * This assumes the raw data has the same byte order as the native order.
+     */
+    public static <T> T parse(final Class<T> clazz, final byte[] bytes) {
+        final ByteBuffer buf = ByteBuffer.wrap(bytes);
+        buf.order(ByteOrder.nativeOrder());
+        return parse(clazz, buf);
+    }
+
     private static int getSizeInternal(final FieldInfo[] fieldInfos) {
         int size = 0;
         for (FieldInfo fi : fieldInfos) {