Add a small testcase for snapshot writer.
update_engine heavily relies on snapshot writer, add a testcase
Test: th
Change-Id: I4e3cf47dcff92ec4df0b3b84a0a8c7cb7866e7e7
diff --git a/fs_mgr/libsnapshot/Android.bp b/fs_mgr/libsnapshot/Android.bp
index ea92d25..e28cfd4 100644
--- a/fs_mgr/libsnapshot/Android.bp
+++ b/fs_mgr/libsnapshot/Android.bp
@@ -251,6 +251,7 @@
"snapshot_metadata_updater_test.cpp",
"snapshot_reader_test.cpp",
"snapshot_test.cpp",
+ "snapshot_writer_test.cpp",
],
shared_libs: [
"libbinder",
diff --git a/fs_mgr/libsnapshot/snapshot_writer.cpp b/fs_mgr/libsnapshot/snapshot_writer.cpp
index 8e379e4..080f3b7 100644
--- a/fs_mgr/libsnapshot/snapshot_writer.cpp
+++ b/fs_mgr/libsnapshot/snapshot_writer.cpp
@@ -90,7 +90,9 @@
}
const auto& cow_options = options();
- reader->SetBlockDeviceSize(*cow_options.max_blocks * cow_options.block_size);
+ if (cow_options.max_blocks) {
+ reader->SetBlockDeviceSize(*cow_options.max_blocks * cow_options.block_size);
+ }
return reader;
}
diff --git a/fs_mgr/libsnapshot/snapshot_writer_test.cpp b/fs_mgr/libsnapshot/snapshot_writer_test.cpp
new file mode 100644
index 0000000..da48eb9
--- /dev/null
+++ b/fs_mgr/libsnapshot/snapshot_writer_test.cpp
@@ -0,0 +1,62 @@
+//
+// Copyright (C) 2021 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 <libsnapshot/snapshot.h>
+
+#include <unordered_set>
+
+#include <android-base/file.h>
+#include <gtest/gtest.h>
+#include <libsnapshot/snapshot_writer.h>
+#include <payload_consumer/file_descriptor.h>
+
+namespace android::snapshot {
+class CompressedSnapshotWriterTest : public ::testing::Test {
+ public:
+ static constexpr size_t BLOCK_SIZE = 4096;
+};
+
+TEST_F(CompressedSnapshotWriterTest, ReadAfterWrite) {
+ TemporaryFile cow_device_file{};
+ android::snapshot::CowOptions options{.block_size = BLOCK_SIZE};
+ android::snapshot::CompressedSnapshotWriter snapshot_writer{options};
+ snapshot_writer.SetCowDevice(android::base::unique_fd{cow_device_file.fd});
+ snapshot_writer.Initialize();
+ std::vector<unsigned char> buffer;
+ buffer.resize(BLOCK_SIZE);
+ std::fill(buffer.begin(), buffer.end(), 123);
+
+ ASSERT_TRUE(snapshot_writer.AddRawBlocks(0, buffer.data(), buffer.size()));
+ ASSERT_TRUE(snapshot_writer.Finalize());
+ auto cow_reader = snapshot_writer.OpenReader();
+ ASSERT_NE(cow_reader, nullptr);
+ ASSERT_TRUE(snapshot_writer.AddRawBlocks(1, buffer.data(), buffer.size()));
+ ASSERT_TRUE(snapshot_writer.AddRawBlocks(2, buffer.data(), buffer.size()));
+ ASSERT_TRUE(snapshot_writer.Finalize());
+ // After wrigin some data, if we call OpenReader() again, writes should
+ // be visible to the newly opened reader. update_engine relies on this
+ // behavior for verity writes.
+ cow_reader = snapshot_writer.OpenReader();
+ ASSERT_NE(cow_reader, nullptr);
+ std::vector<unsigned char> read_back;
+ read_back.resize(buffer.size());
+ cow_reader->Seek(BLOCK_SIZE, SEEK_SET);
+ const auto bytes_read = cow_reader->Read(read_back.data(), read_back.size());
+ ASSERT_EQ((size_t)(bytes_read), BLOCK_SIZE);
+ ASSERT_EQ(read_back, buffer);
+}
+
+} // namespace android::snapshot
