audio: import aidl hal

* hardware/interfaces/audio/aidl/default/ at android-16.0.0_r1.

audio/stub/ApeHeader.h

@@ -0,0 +1,63 @@
+/*
+ * Copyright (C) 2025 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#pragma once
+
+#include <cstdint>
+
+namespace aidl::android::hardware::audio::core {
+
+// Simplified APE (Monkey Audio) header definition sufficient to figure out
+// the basic parameters of the encoded file. Only supports the "current"
+// versions of the header (>= 3980).
+
+#pragma pack(push, 4)
+
+// Only the beginning of the descriptor is needed to find the header which
+// follows the descriptor.
+struct ApeDescriptor {
+    uint32_t signature;  // 'MAC ' or 'MACF'
+    uint16_t version;
+    uint16_t padding;
+    uint32_t descriptorSizeBytes;
+    uint32_t headerSizeBytes;
+};
+
+struct ApeHeader {
+    uint16_t compressionLevel;
+    uint16_t flags;
+    uint32_t blocksPerFrame;   // "frames" are encoder frames, while "blocks" are audio frames
+    uint32_t lastFrameBlocks;  // number of "blocks" in the last encoder "frame"
+    uint32_t totalFrames;      // total number of encoder "frames"
+    uint16_t bitsPerSample;
+    uint16_t channelCount;
+    uint32_t sampleRate;
+};
+
+#pragma pack(pop)
+
+// Tries to find APE descriptor and header in the buffer. Returns the position
+// after the header or nullptr if it was not found.
+void* findApeHeader(void* buffer, size_t bufferSizeBytes, ApeHeader** header);
+
+// Clip duration in audio frames ("blocks" in the APE terminology).
+inline int64_t getApeClipDurationFrames(const ApeHeader* header) {
+    return header->totalFrames != 0
+                   ? (header->totalFrames - 1) * header->blocksPerFrame + header->lastFrameBlocks
+                   : 0;
+}
+
+}  // namespace aidl::android::hardware::audio::core