Add a standardized shared memory type
This adds a simple SharedFileRegion type that can be used to pass blocks
of shared memory between processes in a structured AIDL interface.
In addition a small utility library is provided for interfacing with
existing code that uses IMemory.
The intention is to add utilities for direct usage of the memory
content.
Bug: 160253486
Test: Ran the included unit test. Integration testing as part of whole
topic tests via the audio effect tests.
Change-Id: I3f923047e364ba44fda316bdd563561ebec201b2
diff --git a/media/libshmem/ShmemTest.cpp b/media/libshmem/ShmemTest.cpp
new file mode 100644
index 0000000..4f11b51
--- /dev/null
+++ b/media/libshmem/ShmemTest.cpp
@@ -0,0 +1,87 @@
+/*
+ * Copyright (C) 2020 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 <gtest/gtest.h>
+
+#include "binder/MemoryBase.h"
+#include "binder/MemoryHeapBase.h"
+#include "media/ShmemCompat.h"
+#include "media/ShmemUtil.h"
+
+namespace android {
+namespace media {
+namespace {
+
+// Creates a SharedFileRegion instance with a null FD.
+SharedFileRegion makeSharedFileRegion(int64_t offset, int64_t size) {
+ SharedFileRegion shmem;
+ shmem.offset = offset;
+ shmem.size = size;
+ return shmem;
+}
+
+sp<IMemory> makeIMemory(const std::vector<uint8_t>& content) {
+ constexpr size_t kOffset = 19;
+
+ sp<MemoryHeapBase> heap = new MemoryHeapBase(content.size());
+ sp<IMemory> result = sp<MemoryBase>::make(heap, kOffset, content.size());
+ memcpy(result->unsecurePointer(), content.data(), content.size());
+ return result;
+}
+
+TEST(ShmemTest, Validate) {
+ EXPECT_TRUE(validateSharedFileRegion(makeSharedFileRegion(0, 0)));
+ EXPECT_TRUE(validateSharedFileRegion(makeSharedFileRegion(1, 2)));
+ EXPECT_FALSE(validateSharedFileRegion(makeSharedFileRegion(-1, 2)));
+ EXPECT_FALSE(validateSharedFileRegion(makeSharedFileRegion(2, -1)));
+ EXPECT_TRUE(validateSharedFileRegion(makeSharedFileRegion(
+ std::numeric_limits<int64_t>::max(),
+ std::numeric_limits<int64_t>::max())));
+}
+
+TEST(ShmemTest, Conversion) {
+ sp<IMemory> reconstructed;
+ {
+ SharedFileRegion shmem;
+ sp<IMemory> imem = makeIMemory({6, 5, 3});
+ ASSERT_TRUE(convertIMemoryToSharedFileRegion(imem, &shmem));
+ ASSERT_EQ(3, shmem.size);
+ ASSERT_GE(shmem.fd.get(), 0);
+ ASSERT_TRUE(convertSharedFileRegionToIMemory(shmem, &reconstructed));
+ }
+ ASSERT_EQ(3, reconstructed->size());
+ const uint8_t* p =
+ reinterpret_cast<const uint8_t*>(reconstructed->unsecurePointer());
+ EXPECT_EQ(6, p[0]);
+ EXPECT_EQ(5, p[1]);
+ EXPECT_EQ(3, p[2]);
+}
+
+TEST(ShmemTest, NullConversion) {
+ sp<IMemory> reconstructed;
+ {
+ SharedFileRegion shmem;
+ sp<IMemory> imem;
+ ASSERT_TRUE(convertIMemoryToSharedFileRegion(imem, &shmem));
+ ASSERT_EQ(0, shmem.size);
+ ASSERT_LT(shmem.fd.get(), 0);
+ ASSERT_TRUE(convertSharedFileRegionToIMemory(shmem, &reconstructed));
+ }
+ ASSERT_EQ(nullptr, reconstructed);
+}
+
+} // namespace
+} // namespace media
+} // namespace android