diff --git a/include/binder/Parcel.h b/include/binder/Parcel.h
index cf2fa47..5d36526 100644
--- a/include/binder/Parcel.h
+++ b/include/binder/Parcel.h
@@ -72,6 +72,8 @@
     status_t            appendFrom(const Parcel *parcel,
                                    size_t start, size_t len);
 
+    int                 compareData(const Parcel& other);
+
     bool                allowFds() const;
     bool                pushAllowFds(bool allowFds);
     void                restoreAllowFds(bool lastValue);
diff --git a/libs/binder/Parcel.cpp b/libs/binder/Parcel.cpp
index da94305..39bb078 100644
--- a/libs/binder/Parcel.cpp
+++ b/libs/binder/Parcel.cpp
@@ -553,6 +553,14 @@
     return err;
 }
 
+int Parcel::compareData(const Parcel& other) {
+    size_t size = dataSize();
+    if (size != other.dataSize()) {
+        return size < other.dataSize() ? -1 : 1;
+    }
+    return memcmp(data(), other.data(), size);
+}
+
 bool Parcel::allowFds() const
 {
     return mAllowFds;