Don't allocate new array in Parcel#readByteArray (4610044c) · Commits · e / os / android_frameworks_base

core/java/android/os/Parcel.java

+3 −5

Original line number	Diff line number	Diff line
		@@ -293,6 +293,7 @@ public final class Parcel {
		private static native long nativeWriteFileDescriptor(long nativePtr, FileDescriptor val);

		private static native byte[] nativeCreateByteArray(long nativePtr);
		private static native boolean nativeReadByteArray(long nativePtr, byte[] dest, int destLen);
		private static native byte[] nativeReadBlob(long nativePtr);
		@FastNative
		private static native int nativeReadInt(long nativePtr);
		@@ -2191,11 +2192,8 @@ public final class Parcel {
		* given byte array.
		*/
		public final void readByteArray(byte[] val) {
		// TODO: make this a native method to avoid the extra copy.
		byte[] ba = createByteArray();
		if (ba.length == val.length) {
		System.arraycopy(ba, 0, val, 0, ba.length);
		} else {
		boolean valid = nativeReadByteArray(mNativePtr, val, (val != null) ? val.length : 0);
		if (!valid) {
		throw new RuntimeException("bad array lengths");
		}
		}

core/jni/android_os_Parcel.cpp

+26 −3

Original line number	Diff line number	Diff line
		@@ -164,8 +164,8 @@ static void android_os_Parcel_restoreAllowFds(JNIEnv* env, jclass clazz, jlong n
		}
		}

		static void android_os_Parcel_writeNative(JNIEnv* env, jclass clazz, jlong nativePtr, jobject data,
		jint offset, jint length)
		static void android_os_Parcel_writeByteArray(JNIEnv* env, jclass clazz, jlong nativePtr,
		jobject data, jint offset, jint length)
		{
		Parcel* parcel = reinterpret_cast<Parcel*>(nativePtr);
		if (parcel == NULL) {
		@@ -346,6 +346,28 @@ static jbyteArray android_os_Parcel_createByteArray(JNIEnv* env, jclass clazz, j
		return ret;
		}

		static jboolean android_os_Parcel_readByteArray(JNIEnv* env, jclass clazz, jlong nativePtr,
		jobject dest, jint destLen)
		{
		jboolean ret = JNI_FALSE;
		Parcel* parcel = reinterpret_cast<Parcel*>(nativePtr);
		if (parcel == NULL) {
		return ret;
		}

		int32_t len = parcel->readInt32();
		if (len >= 0 && len <= (int32_t)parcel->dataAvail() && len == destLen) {
		jbyte* ar = (jbyte*)env->GetPrimitiveArrayCritical((jarray)dest, 0);
		if (ar) {
		const void* data = parcel->readInplace(len);
		memcpy(ar, data, len);
		env->ReleasePrimitiveArrayCritical((jarray)dest, ar, 0);
		ret = JNI_TRUE;
		}
		}
		return ret;
		}

		static jbyteArray android_os_Parcel_readBlob(JNIEnv* env, jclass clazz, jlong nativePtr)
		{
		jbyteArray ret = NULL;
		@@ -757,7 +779,7 @@ static const JNINativeMethod gParcelMethods[] = {
		// @FastNative
		{"nativeRestoreAllowFds", "(JZ)V", (void*)android_os_Parcel_restoreAllowFds},

		{"nativeWriteByteArray", "(J[BII)V", (void*)android_os_Parcel_writeNative},
		{"nativeWriteByteArray", "(J[BII)V", (void*)android_os_Parcel_writeByteArray},
		{"nativeWriteBlob", "(J[BII)V", (void*)android_os_Parcel_writeBlob},
		// @FastNative
		{"nativeWriteInt", "(JI)V", (void*)android_os_Parcel_writeInt},
		@@ -772,6 +794,7 @@ static const JNINativeMethod gParcelMethods[] = {
		{"nativeWriteFileDescriptor", "(JLjava/io/FileDescriptor;)J", (void*)android_os_Parcel_writeFileDescriptor},

		{"nativeCreateByteArray", "(J)[B", (void*)android_os_Parcel_createByteArray},
		{"nativeReadByteArray", "(J[BI)Z", (void*)android_os_Parcel_readByteArray},
		{"nativeReadBlob", "(J)[B", (void*)android_os_Parcel_readBlob},
		// @FastNative
		{"nativeReadInt", "(J)I", (void*)android_os_Parcel_readInt},