Merge changes from topic "nativewindow-rust" into main

* changes:
  nativewindow: Misc. improvements for AHardwareBuffer Rust wrapper
  nativewindow: Add more benchmarks to evaluate FFI costs
  nativewindow: Add C++/Rust benchmarks
  Add missing safety comments.
  libnativewindow: Add rust library and set up bindgen

8 files changed, 650 insertions, 0 deletions

diff --git a/libs/nativewindow/TEST_MAPPING b/libs/nativewindow/TEST_MAPPING
index 3d7f3c28f4..bbad757a48 100644
--- a/libs/nativewindow/TEST_MAPPING
+++ b/libs/nativewindow/TEST_MAPPING
@@ -3,5 +3,13 @@
     {
       "name": "libnativewindow_test"
     }
+  ],
+  "postsubmit": [
+    {
+      "name": "libnativewindow_bindgen_test"
+    },
+    {
+      "name": "libnativewindow_rs-internal_test"
+    }
   ]
 }
diff --git a/libs/nativewindow/rust/Android.bp b/libs/nativewindow/rust/Android.bp
new file mode 100644
index 0000000000..dc1575ca33
--- /dev/null
+++ b/libs/nativewindow/rust/Android.bp
@@ -0,0 +1,87 @@
+// Copyright (C) 2023 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.
+
+package {
+    default_applicable_licenses: [
+        "frameworks_native_libs_nativewindow_license",
+    ],
+}
+
+rust_bindgen {
+    name: "libnativewindow_bindgen",
+    crate_name: "nativewindow_bindgen",
+    wrapper_src: "sys/nativewindow_bindings.h",
+    source_stem: "bindings",
+    bindgen_flags: [
+        "--constified-enum-module=AHardwareBuffer_Format",
+        "--bitfield-enum=AHardwareBuffer_UsageFlags",
+
+        "--allowlist-file=.*/nativewindow/include/.*\\.h",
+
+        "--with-derive-eq",
+        "--with-derive-partialeq",
+    ],
+    shared_libs: [
+        "libnativewindow",
+    ],
+
+    // Currently necessary for host builds
+    // TODO(b/31559095): bionic on host should define this
+    target: {
+        darwin: {
+            enabled: false,
+        },
+    },
+    min_sdk_version: "VanillaIceCream",
+}
+
+rust_test {
+    name: "libnativewindow_bindgen_test",
+    srcs: [":libnativewindow_bindgen"],
+    crate_name: "nativewindow_bindgen_test",
+    test_suites: ["general-tests"],
+    auto_gen_config: true,
+    clippy_lints: "none",
+    lints: "none",
+}
+
+rust_defaults {
+    name: "libnativewindow_defaults",
+    srcs: ["src/lib.rs"],
+    rustlibs: [
+        "libnativewindow_bindgen",
+    ],
+}
+
+rust_library {
+    name: "libnativewindow_rs",
+    crate_name: "nativewindow",
+    defaults: ["libnativewindow_defaults"],
+
+    // Currently necessary for host builds
+    // TODO(b/31559095): bionic on host should define this
+    target: {
+        darwin: {
+            enabled: false,
+        },
+    },
+    min_sdk_version: "VanillaIceCream",
+}
+
+rust_test {
+    name: "libnativewindow_rs-internal_test",
+    crate_name: "nativewindow",
+    defaults: ["libnativewindow_defaults"],
+    test_suites: ["general-tests"],
+}
diff --git a/libs/nativewindow/rust/src/lib.rs b/libs/nativewindow/rust/src/lib.rs
new file mode 100644
index 0000000000..6eb3bbcdb3
--- /dev/null
+++ b/libs/nativewindow/rust/src/lib.rs
@@ -0,0 +1,329 @@
+// Copyright (C) 2023 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.
+
+//! Pleasant Rust bindings for libnativewindow, including AHardwareBuffer
+
+extern crate nativewindow_bindgen as ffi;
+
+pub use ffi::{AHardwareBuffer, AHardwareBuffer_Format, AHardwareBuffer_UsageFlags};
+
+use std::fmt::{self, Debug, Formatter};
+use std::mem::ManuallyDrop;
+use std::ptr::{self, NonNull};
+
+/// Wrapper around an opaque C AHardwareBuffer.
+#[derive(PartialEq, Eq)]
+pub struct HardwareBuffer(NonNull<AHardwareBuffer>);
+
+impl HardwareBuffer {
+    /// Test whether the given format and usage flag combination is allocatable.  If this function
+    /// returns true, it means that a buffer with the given description can be allocated on this
+    /// implementation, unless resource exhaustion occurs. If this function returns false, it means
+    /// that the allocation of the given description will never succeed.
+    ///
+    /// Available since API 29
+    pub fn is_supported(
+        width: u32,
+        height: u32,
+        layers: u32,
+        format: AHardwareBuffer_Format::Type,
+        usage: AHardwareBuffer_UsageFlags,
+        stride: u32,
+    ) -> bool {
+        let buffer_desc = ffi::AHardwareBuffer_Desc {
+            width,
+            height,
+            layers,
+            format,
+            usage: usage.0,
+            stride,
+            rfu0: 0,
+            rfu1: 0,
+        };
+        // SAFETY: *buffer_desc will never be null.
+        let status = unsafe { ffi::AHardwareBuffer_isSupported(&buffer_desc) };
+
+        status == 1
+    }
+
+    /// Allocates a buffer that matches the passed AHardwareBuffer_Desc. If allocation succeeds, the
+    /// buffer can be used according to the usage flags specified in its description. If a buffer is
+    /// used in ways not compatible with its usage flags, the results are undefined and may include
+    /// program termination.
+    ///
+    /// Available since API level 26.
+    #[inline]
+    pub fn new(
+        width: u32,
+        height: u32,
+        layers: u32,
+        format: AHardwareBuffer_Format::Type,
+        usage: AHardwareBuffer_UsageFlags,
+    ) -> Option<Self> {
+        let buffer_desc = ffi::AHardwareBuffer_Desc {
+            width,
+            height,
+            layers,
+            format,
+            usage: usage.0,
+            stride: 0,
+            rfu0: 0,
+            rfu1: 0,
+        };
+        let mut ptr = ptr::null_mut();
+        // SAFETY: The returned pointer is valid until we drop/deallocate it. The function may fail
+        // and return a status, but we check it later.
+        let status = unsafe { ffi::AHardwareBuffer_allocate(&buffer_desc, &mut ptr) };
+
+        if status == 0 {
+            Some(Self(NonNull::new(ptr).expect("Allocated AHardwareBuffer was null")))
+        } else {
+            None
+        }
+    }
+
+    /// Adopts the raw pointer and wraps it in a Rust AHardwareBuffer.
+    ///
+    /// # Errors
+    ///
+    /// Will panic if buffer_ptr is null.
+    ///
+    /// # Safety
+    ///
+    /// This function adopts the pointer but does NOT increment the refcount on the buffer. If the
+    /// caller uses the pointer after the created object is dropped it will cause a memory leak.
+    pub unsafe fn from_raw(buffer_ptr: NonNull<AHardwareBuffer>) -> Self {
+        Self(buffer_ptr)
+    }
+
+    /// Get the internal |AHardwareBuffer| pointer without decrementing the refcount. This can
+    /// be used to provide a pointer to the AHB for a C/C++ API over the FFI.
+    pub fn into_raw(self) -> NonNull<AHardwareBuffer> {
+        let buffer = ManuallyDrop::new(self);
+        buffer.0
+    }
+
+    /// Get the system wide unique id for an AHardwareBuffer. This function may panic in extreme
+    /// and undocumented circumstances.
+    ///
+    /// Available since API level 31.
+    pub fn id(&self) -> u64 {
+        let mut out_id = 0;
+        // SAFETY: Neither pointers can be null.
+        let status = unsafe { ffi::AHardwareBuffer_getId(self.0.as_ref(), &mut out_id) };
+        assert_eq!(status, 0, "id() failed for AHardwareBuffer with error code: {status}");
+
+        out_id
+    }
+
+    /// Get the width of this buffer
+    pub fn width(&self) -> u32 {
+        self.description().width
+    }
+
+    /// Get the height of this buffer
+    pub fn height(&self) -> u32 {
+        self.description().height
+    }
+
+    /// Get the number of layers of this buffer
+    pub fn layers(&self) -> u32 {
+        self.description().layers
+    }
+
+    /// Get the format of this buffer
+    pub fn format(&self) -> AHardwareBuffer_Format::Type {
+        self.description().format
+    }
+
+    /// Get the usage bitvector of this buffer
+    pub fn usage(&self) -> AHardwareBuffer_UsageFlags {
+        AHardwareBuffer_UsageFlags(self.description().usage)
+    }
+
+    /// Get the stride of this buffer
+    pub fn stride(&self) -> u32 {
+        self.description().stride
+    }
+
+    fn description(&self) -> ffi::AHardwareBuffer_Desc {
+        let mut buffer_desc = ffi::AHardwareBuffer_Desc {
+            width: 0,
+            height: 0,
+            layers: 0,
+            format: 0,
+            usage: 0,
+            stride: 0,
+            rfu0: 0,
+            rfu1: 0,
+        };
+        // SAFETY: neither the buffer nor AHardwareBuffer_Desc pointers will be null.
+        unsafe { ffi::AHardwareBuffer_describe(self.0.as_ref(), &mut buffer_desc) };
+        buffer_desc
+    }
+}
+
+impl Drop for HardwareBuffer {
+    fn drop(&mut self) {
+        // SAFETY: self.0 will never be null. AHardwareBuffers allocated from within Rust will have
+        // a refcount of one, and there is a safety warning on taking an AHardwareBuffer from a raw
+        // pointer requiring callers to ensure the refcount is managed appropriately.
+        unsafe { ffi::AHardwareBuffer_release(self.0.as_ptr()) }
+    }
+}
+
+impl Debug for HardwareBuffer {
+    fn fmt(&self, f: &mut Formatter<'_>) -> fmt::Result {
+        f.debug_struct("HardwareBuffer").field("id", &self.id()).finish()
+    }
+}
+
+impl Clone for HardwareBuffer {
+    fn clone(&self) -> Self {
+        // SAFETY: ptr is guaranteed to be non-null and the acquire can not fail.
+        unsafe { ffi::AHardwareBuffer_acquire(self.0.as_ptr()) };
+        Self(self.0)
+    }
+}
+
+// SAFETY: The underlying *AHardwareBuffers can be moved between threads.
+unsafe impl Send for HardwareBuffer {}
+
+// SAFETY: The underlying *AHardwareBuffers can be used from multiple threads.
+//
+// AHardwareBuffers are backed by C++ GraphicBuffers, which are mostly immutable. The only cases
+// where they are not immutable are:
+//
+//   - reallocation (which is never actually done across the codebase and requires special
+//     privileges/platform code access to do)
+//   - "locking" for reading/writing (which is explicitly allowed to be done across multiple threads
+//     according to the docs on the underlying gralloc calls)
+unsafe impl Sync for HardwareBuffer {}
+
+#[cfg(test)]
+mod test {
+    use super::*;
+
+    #[test]
+    fn create_valid_buffer_returns_ok() {
+        let buffer = HardwareBuffer::new(
+            512,
+            512,
+            1,
+            AHardwareBuffer_Format::AHARDWAREBUFFER_FORMAT_R8G8B8A8_UNORM,
+            AHardwareBuffer_UsageFlags::AHARDWAREBUFFER_USAGE_CPU_READ_OFTEN,
+        );
+        assert!(buffer.is_some());
+    }
+
+    #[test]
+    fn create_invalid_buffer_returns_err() {
+        let buffer = HardwareBuffer::new(512, 512, 1, 0, AHardwareBuffer_UsageFlags(0));
+        assert!(buffer.is_none());
+    }
+
+    #[test]
+    fn from_raw_allows_getters() {
+        let buffer_desc = ffi::AHardwareBuffer_Desc {
+            width: 1024,
+            height: 512,
+            layers: 1,
+            format: AHardwareBuffer_Format::AHARDWAREBUFFER_FORMAT_R8G8B8A8_UNORM,
+            usage: AHardwareBuffer_UsageFlags::AHARDWAREBUFFER_USAGE_CPU_READ_OFTEN.0,
+            stride: 0,
+            rfu0: 0,
+            rfu1: 0,
+        };
+        let mut raw_buffer_ptr = ptr::null_mut();
+
+        // SAFETY: The pointers are valid because they come from references, and
+        // `AHardwareBuffer_allocate` doesn't retain them after it returns.
+        let status = unsafe { ffi::AHardwareBuffer_allocate(&buffer_desc, &mut raw_buffer_ptr) };
+        assert_eq!(status, 0);
+
+        // SAFETY: The pointer must be valid because it was just allocated successfully, and we
+        // don't use it after calling this.
+        let buffer = unsafe { HardwareBuffer::from_raw(NonNull::new(raw_buffer_ptr).unwrap()) };
+        assert_eq!(buffer.width(), 1024);
+    }
+
+    #[test]
+    fn basic_getters() {
+        let buffer = HardwareBuffer::new(
+            1024,
+            512,
+            1,
+            AHardwareBuffer_Format::AHARDWAREBUFFER_FORMAT_R8G8B8A8_UNORM,
+            AHardwareBuffer_UsageFlags::AHARDWAREBUFFER_USAGE_CPU_READ_OFTEN,
+        )
+        .expect("Buffer with some basic parameters was not created successfully");
+
+        assert_eq!(buffer.width(), 1024);
+        assert_eq!(buffer.height(), 512);
+        assert_eq!(buffer.layers(), 1);
+        assert_eq!(buffer.format(), AHardwareBuffer_Format::AHARDWAREBUFFER_FORMAT_R8G8B8A8_UNORM);
+        assert_eq!(
+            buffer.usage(),
+            AHardwareBuffer_UsageFlags::AHARDWAREBUFFER_USAGE_CPU_READ_OFTEN
+        );
+    }
+
+    #[test]
+    fn id_getter() {
+        let buffer = HardwareBuffer::new(
+            1024,
+            512,
+            1,
+            AHardwareBuffer_Format::AHARDWAREBUFFER_FORMAT_R8G8B8A8_UNORM,
+            AHardwareBuffer_UsageFlags::AHARDWAREBUFFER_USAGE_CPU_READ_OFTEN,
+        )
+        .expect("Buffer with some basic parameters was not created successfully");
+
+        assert_ne!(0, buffer.id());
+    }
+
+    #[test]
+    fn clone() {
+        let buffer = HardwareBuffer::new(
+            1024,
+            512,
+            1,
+            AHardwareBuffer_Format::AHARDWAREBUFFER_FORMAT_R8G8B8A8_UNORM,
+            AHardwareBuffer_UsageFlags::AHARDWAREBUFFER_USAGE_CPU_READ_OFTEN,
+        )
+        .expect("Buffer with some basic parameters was not created successfully");
+        let buffer2 = buffer.clone();
+
+        assert_eq!(buffer, buffer2);
+    }
+
+    #[test]
+    fn into_raw() {
+        let buffer = HardwareBuffer::new(
+            1024,
+            512,
+            1,
+            AHardwareBuffer_Format::AHARDWAREBUFFER_FORMAT_R8G8B8A8_UNORM,
+            AHardwareBuffer_UsageFlags::AHARDWAREBUFFER_USAGE_CPU_READ_OFTEN,
+        )
+        .expect("Buffer with some basic parameters was not created successfully");
+        let buffer2 = buffer.clone();
+
+        let raw_buffer = buffer.into_raw();
+        // SAFETY: This is the same pointer we had before.
+        let remade_buffer = unsafe { HardwareBuffer::from_raw(raw_buffer) };
+
+        assert_eq!(remade_buffer, buffer2);
+    }
+}
diff --git a/libs/nativewindow/rust/sys/nativewindow_bindings.h b/libs/nativewindow/rust/sys/nativewindow_bindings.h
new file mode 100644
index 0000000000..e652aee711
--- /dev/null
+++ b/libs/nativewindow/rust/sys/nativewindow_bindings.h
@@ -0,0 +1,20 @@
+/*
+ * Copyright 2023 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.
+ */
+
+#include <android/data_space.h>
+#include <android/hardware_buffer.h>
+#include <android/hdr_metadata.h>
+#include <android/native_window.h>
diff --git a/libs/nativewindow/tests/benchmark/Android.bp b/libs/nativewindow/tests/benchmark/Android.bp
new file mode 100644
index 0000000000..6f844cf864
--- /dev/null
+++ b/libs/nativewindow/tests/benchmark/Android.bp
@@ -0,0 +1,50 @@
+// Copyright (C) 2023 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.
+
+cc_defaults {
+    name: "nativewindow_benchmark_defaults_cc",
+    shared_libs: ["libnativewindow"],
+    static_libs: [
+        "libbase",
+        "libgoogle-benchmark-main",
+    ],
+    test_suites: [
+        "device-tests",
+        "NativeWindowBenchmarks",
+    ],
+}
+
+cc_benchmark {
+    name: "nativewindow_buffer_benchmarks_cc",
+    srcs: ["buffer_benchmarks.cc"],
+    defaults: ["nativewindow_benchmark_defaults_cc"],
+}
+
+rust_defaults {
+    name: "nativewindow_benchmark_defaults_rs",
+    rustlibs: [
+        "libnativewindow_rs",
+        "libcriterion",
+    ],
+    test_suites: [
+        "device-tests",
+        "NativeWindowBenchmarks",
+    ],
+}
+
+rust_benchmark {
+    name: "nativewindow_buffer_benchmarks_rs",
+    srcs: ["buffer_benchmarks.rs"],
+    defaults: ["nativewindow_benchmark_defaults_rs"],
+}
diff --git a/libs/nativewindow/tests/benchmark/README.md b/libs/nativewindow/tests/benchmark/README.md
new file mode 100644
index 0000000000..7eae538dd2
--- /dev/null
+++ b/libs/nativewindow/tests/benchmark/README.md
@@ -0,0 +1,22 @@
+# libnativewindow Benchmarks
+
+This directory contains benchmarks for the C++ and Rust variants of
+libnativewindow.
+
+## Running
+
+It is currently a little tricky to get statistics from Rust benchmarks directly
+from tradefed. But we can hack it by using atest to build/push, then running
+the benchmarks by hand to get stats.
+
+```
+  $ atest nativewindow_buffer_benchmarks_rs nativewindow_buffer_benchmarks_cc -d
+  $ adb shell /data/local/tmp/nativewindow_buffer_benchmarks_cc/x86_64/nativewindow_buffer_benchmarks_cc
+  $ adb shell /data/local/tmp/nativewindow_buffer_benchmarks_rs/x86_64/nativewindow_buffer_benchmarks_rs --bench
+```
+
+## Results
+
+On a remote emulator, the results we see from the benchmarks from Rust and C++
+seem to be roughly equivalent! Allocating/deallocating a 720p buffer takes
+~2.3ms on each.
diff --git a/libs/nativewindow/tests/benchmark/buffer_benchmarks.cc b/libs/nativewindow/tests/benchmark/buffer_benchmarks.cc
new file mode 100644
index 0000000000..9b31993809
--- /dev/null
+++ b/libs/nativewindow/tests/benchmark/buffer_benchmarks.cc
@@ -0,0 +1,74 @@
+// Copyright (C) 2023 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.
+
+#include <android-base/macros.h>
+#include <android/hardware_buffer.h>
+#include <benchmark/benchmark.h>
+
+constexpr AHardwareBuffer_Desc k720pDesc = {.width = 1280,
+                                            .height = 720,
+                                            .layers = 1,
+                                            .format = AHARDWAREBUFFER_FORMAT_R8G8B8A8_UNORM,
+                                            .usage = AHARDWAREBUFFER_USAGE_CPU_READ_OFTEN,
+                                            .stride = 0};
+
+static void BM_BufferAllocationDeallocation(benchmark::State& state) {
+    AHardwareBuffer* buffer = nullptr;
+    for (auto _ : state) {
+        int status = AHardwareBuffer_allocate(&k720pDesc, &buffer);
+        if (UNLIKELY(status != 0)) {
+            state.SkipWithError("Unable to allocate buffer.");
+        }
+        AHardwareBuffer_release(buffer);
+        buffer = nullptr;
+    }
+}
+BENCHMARK(BM_BufferAllocationDeallocation);
+
+static void BM_AHardwareBuffer_Id(benchmark::State& state) {
+    AHardwareBuffer* buffer = nullptr;
+    int status = AHardwareBuffer_allocate(&k720pDesc, &buffer);
+    if (UNLIKELY(status != 0)) {
+        state.SkipWithError("Unable to allocate buffer.");
+    }
+
+    for (auto _ : state) {
+        uint64_t id = 0;
+        int status = AHardwareBuffer_getId(buffer, &id);
+        if (UNLIKELY(status != 0)) {
+            state.SkipWithError("Unable to get ID.");
+        }
+    }
+
+    AHardwareBuffer_release(buffer);
+}
+BENCHMARK(BM_AHardwareBuffer_Id);
+
+static void BM_AHardwareBuffer_Desc(benchmark::State& state) {
+    AHardwareBuffer* buffer = nullptr;
+    int status = AHardwareBuffer_allocate(&k720pDesc, &buffer);
+    if (UNLIKELY(status != 0)) {
+        state.SkipWithError("Unable to allocate buffer.");
+    }
+
+    for (auto _ : state) {
+        AHardwareBuffer_Desc desc = {};
+        AHardwareBuffer_describe(buffer, &desc);
+    }
+
+    AHardwareBuffer_release(buffer);
+}
+BENCHMARK(BM_AHardwareBuffer_Desc);
+
+BENCHMARK_MAIN();
diff --git a/libs/nativewindow/tests/benchmark/buffer_benchmarks.rs b/libs/nativewindow/tests/benchmark/buffer_benchmarks.rs
new file mode 100644
index 0000000000..876f6c8e26
--- /dev/null
+++ b/libs/nativewindow/tests/benchmark/buffer_benchmarks.rs
@@ -0,0 +1,60 @@
+// Copyright (C) 2023 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.
+
+//! Benchmark for libnativewindow AHardwareBuffer bindings
+
+#![allow(dead_code)]
+#![allow(missing_docs)]
+
+use criterion::*;
+use nativewindow::*;
+
+#[inline]
+fn create_720p_buffer() -> HardwareBuffer {
+    HardwareBuffer::new(
+        1280,
+        720,
+        1,
+        AHardwareBuffer_Format::AHARDWAREBUFFER_FORMAT_R8G8B8A8_UNORM,
+        AHardwareBuffer_UsageFlags::AHARDWAREBUFFER_USAGE_CPU_READ_OFTEN,
+    )
+    .unwrap()
+}
+
+fn criterion_benchmark(c: &mut Criterion) {
+    c.bench_function("allocate_deallocate", |b| {
+        b.iter(|| {
+            let buffer = create_720p_buffer();
+            drop(buffer);
+        })
+    });
+
+    let buffer = create_720p_buffer();
+    c.bench_with_input(BenchmarkId::new("id", "buffer"), &buffer, |b, buffer| {
+        b.iter(|| {
+            buffer.id();
+        })
+    });
+
+    // This benchmark exercises getters that need to fetch data via an
+    // underlying call to AHardwareBuffer_describe.
+    c.bench_with_input(BenchmarkId::new("desc", "buffer"), &buffer, |b, buffer| {
+        b.iter(|| {
+            buffer.width();
+        })
+    });
+}
+
+criterion_group!(benches, criterion_benchmark);
+criterion_main!(benches);