Separated v4l2_metadata into two pieces.

v4l2_metadata and metadata/metadata. The previous design did not work
as intended for testing (it incorrectly assumed that a constructor
would call an overridden method of a child class), plus this way
makes more sense.

BUG: 30140438
Change-Id: I1293535932fed6daed766682421b1215739e17dd
TEST: Unit tests pass
diff --git a/modules/camera/3_4/metadata/metadata.cpp b/modules/camera/3_4/metadata/metadata.cpp
new file mode 100644
index 0000000..8867e4d
--- /dev/null
+++ b/modules/camera/3_4/metadata/metadata.cpp
@@ -0,0 +1,139 @@
+/*
+ * Copyright 2016 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 "metadata.h"
+
+#include <camera/CameraMetadata.h>
+
+#include "../common.h"
+
+namespace v4l2_camera_hal {
+
+Metadata::Metadata() { HAL_LOG_ENTER(); }
+
+Metadata::~Metadata() { HAL_LOG_ENTER(); }
+
+void Metadata::AddComponent(
+    std::unique_ptr<PartialMetadataInterface> component) {
+  HAL_LOG_ENTER();
+
+  components_.push_back(std::move(component));
+}
+
+int Metadata::FillStaticMetadata(camera_metadata_t** metadata) {
+  HAL_LOG_ENTER();
+
+  std::vector<int32_t> static_tags;
+  std::vector<int32_t> control_tags;
+  std::vector<int32_t> dynamic_tags;
+  int res = 0;
+
+  for (auto& component : components_) {
+    // Populate the fields.
+    res = component->PopulateStaticFields(metadata);
+    if (res) {
+      // Exit on error.
+      HAL_LOGE("Failed to get all static properties.");
+      return res;
+    }
+
+    // Note what tags the component adds.
+    const std::vector<int32_t>* tags = &component->StaticTags();
+    static_tags.insert(static_tags.end(), tags->begin(), tags->end());
+    tags = &component->ControlTags();
+    control_tags.insert(control_tags.end(), tags->begin(), tags->end());
+    tags = &component->DynamicTags();
+    dynamic_tags.insert(dynamic_tags.end(), tags->begin(), tags->end());
+  }
+
+  // Populate the meta fields.
+  android::CameraMetadata metadata_wrapper(*metadata);
+  static_tags.push_back(ANDROID_REQUEST_AVAILABLE_REQUEST_KEYS);
+  res = metadata_wrapper.update(ANDROID_REQUEST_AVAILABLE_REQUEST_KEYS,
+                                control_tags.data(), control_tags.size());
+  if (res != android::OK) {
+    HAL_LOGE("Failed to add request keys meta key.");
+    return -ENODEV;
+  }
+  static_tags.push_back(ANDROID_REQUEST_AVAILABLE_RESULT_KEYS);
+  res = metadata_wrapper.update(ANDROID_REQUEST_AVAILABLE_RESULT_KEYS,
+                                dynamic_tags.data(), dynamic_tags.size());
+  if (res != android::OK) {
+    HAL_LOGE("Failed to add result keys meta key.");
+    return -ENODEV;
+  }
+  static_tags.push_back(ANDROID_REQUEST_AVAILABLE_CHARACTERISTICS_KEYS);
+  res = metadata_wrapper.update(ANDROID_REQUEST_AVAILABLE_CHARACTERISTICS_KEYS,
+                                static_tags.data(), static_tags.size());
+  if (res != android::OK) {
+    HAL_LOGE("Failed to add characteristics keys meta key.");
+    return -ENODEV;
+  }
+
+  *metadata = metadata_wrapper.release();
+  return 0;
+}
+
+bool Metadata::IsValidRequest(const camera_metadata_t* metadata) {
+  HAL_LOG_ENTER();
+
+  // Null means "use previous settings", which are inherently valid.
+  if (metadata == nullptr) return true;
+
+  for (auto& component : components_) {
+    // Check that all components support the values requested of them.
+    bool valid_request = component->SupportsRequestValues(metadata);
+    if (!valid_request) {
+      // Exit early if possible.
+      return false;
+    }
+  }
+
+  return true;
+}
+
+int Metadata::SetRequestSettings(const camera_metadata_t* metadata) {
+  HAL_LOG_ENTER();
+
+  // Null means "use previous settings".
+  if (metadata == nullptr) return 0;
+
+  for (auto& component : components_) {
+    int res = component->SetRequestValues(metadata);
+    if (res) {
+      // Exit early if possible.
+      HAL_LOGE("Failed to set all requested settings.");
+      return res;
+    }
+  }
+
+  return 0;
+}
+
+int Metadata::FillResultMetadata(camera_metadata_t** metadata) {
+  for (auto& component : components_) {
+    int res = component->PopulateDynamicFields(metadata);
+    if (res) {
+      // Exit early if possible.
+      HAL_LOGE("Failed to get all dynamic result fields.");
+      return res;
+    }
+  }
+
+  return 0;
+}
+
+}  // namespace v4l2_camera_hal
diff --git a/modules/camera/3_4/metadata/metadata.h b/modules/camera/3_4/metadata/metadata.h
new file mode 100644
index 0000000..d25a040
--- /dev/null
+++ b/modules/camera/3_4/metadata/metadata.h
@@ -0,0 +1,52 @@
+/*
+ * Copyright (C) 2016 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.
+ */
+
+#ifndef V4L2_CAMERA_HAL_METADATA_H_
+#define V4L2_CAMERA_HAL_METADATA_H_
+
+#include <hardware/camera3.h>
+
+#include "../common.h"
+#include "partial_metadata_interface.h"
+
+namespace v4l2_camera_hal {
+class Metadata {
+ public:
+  Metadata();
+  virtual ~Metadata();
+
+  int FillStaticMetadata(camera_metadata_t** metadata);
+  bool IsValidRequest(const camera_metadata_t* metadata);
+  int SetRequestSettings(const camera_metadata_t* metadata);
+  int FillResultMetadata(camera_metadata_t** metadata);
+
+ protected:
+  // Helper for the child constructors to fill in metadata components.
+  void AddComponent(std::unique_ptr<PartialMetadataInterface> component);
+
+ private:
+  // The overall metadata is broken down into several distinct pieces.
+  // Note: it is undefined behavior if multiple components share tags.
+  std::vector<std::unique_ptr<PartialMetadataInterface>> components_;
+
+  friend class MetadataTest;
+
+  DISALLOW_COPY_AND_ASSIGN(Metadata);
+};
+
+}  // namespace v4l2_camera_hal
+
+#endif  // V4L2_CAMERA_HAL_V4L2_METADATA_H_
diff --git a/modules/camera/3_4/metadata/metadata_test.cpp b/modules/camera/3_4/metadata/metadata_test.cpp
new file mode 100644
index 0000000..d7da553
--- /dev/null
+++ b/modules/camera/3_4/metadata/metadata_test.cpp
@@ -0,0 +1,277 @@
+/*
+ * Copyright (C) 2016 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 "metadata.h"
+
+#include <memory>
+#include <set>
+#include <vector>
+
+#include <camera/CameraMetadata.h>
+#include <gmock/gmock.h>
+#include <gtest/gtest.h>
+
+#include "metadata/partial_metadata_interface_mock.h"
+
+using testing::AtMost;
+using testing::Return;
+using testing::ReturnRef;
+using testing::Test;
+using testing::_;
+
+namespace v4l2_camera_hal {
+
+class MetadataTest : public Test {
+ protected:
+  virtual void SetUp() {
+    dut_.reset(new Metadata());
+
+    component1_.reset(new PartialMetadataInterfaceMock());
+    component2_.reset(new PartialMetadataInterfaceMock());
+  }
+
+  // Once the component mocks have had expectations set,
+  // add them to the device under test.
+  virtual void AddComponents() {
+    // Don't mind moving; Gmock/Gtest fails on leaked mocks unless disabled by
+    // runtime flags.
+    dut_->AddComponent(std::move(component1_));
+    dut_->AddComponent(std::move(component2_));
+  }
+
+  virtual void CompareTags(const std::set<int32_t>& expected,
+                           const camera_metadata_entry_t& actual) {
+    ASSERT_EQ(expected.size(), actual.count);
+    for (size_t i = 0; i < actual.count; ++i) {
+      EXPECT_NE(expected.find(actual.data.i32[i]), expected.end());
+    }
+  }
+
+  // Device under test.
+  std::unique_ptr<Metadata> dut_;
+  // Mocks.
+  std::unique_ptr<PartialMetadataInterfaceMock> component1_;
+  std::unique_ptr<PartialMetadataInterfaceMock> component2_;
+  // An empty vector to use as necessary.
+  std::vector<int32_t> empty_tags_;
+};
+
+TEST_F(MetadataTest, FillStaticSuccess) {
+  android::CameraMetadata metadata(1);
+  camera_metadata_t* metadata_raw = metadata.release();
+
+  // Should populate all the component static pieces.
+  EXPECT_CALL(*component1_, PopulateStaticFields(_)).WillOnce(Return(0));
+  EXPECT_CALL(*component2_, PopulateStaticFields(_)).WillOnce(Return(0));
+
+  // Should populate the meta keys, by polling each component's keys.
+  std::vector<int32_t> static_tags_1({1, 2});
+  std::vector<int32_t> static_tags_2({3, 4});
+  std::vector<int32_t> control_tags_1({5, 6});
+  std::vector<int32_t> control_tags_2({7, 8});
+  std::vector<int32_t> dynamic_tags_1({9, 10});
+  std::vector<int32_t> dynamic_tags_2({11, 12});
+  EXPECT_CALL(*component1_, StaticTags()).WillOnce(ReturnRef(static_tags_1));
+  EXPECT_CALL(*component1_, ControlTags()).WillOnce(ReturnRef(control_tags_1));
+  EXPECT_CALL(*component1_, DynamicTags()).WillOnce(ReturnRef(dynamic_tags_1));
+  EXPECT_CALL(*component2_, StaticTags()).WillOnce(ReturnRef(static_tags_2));
+  EXPECT_CALL(*component2_, ControlTags()).WillOnce(ReturnRef(control_tags_2));
+  EXPECT_CALL(*component2_, DynamicTags()).WillOnce(ReturnRef(dynamic_tags_2));
+
+  AddComponents();
+  // Should succeed. If it didn't, no reason to continue checking output.
+  ASSERT_EQ(dut_->FillStaticMetadata(&metadata_raw), 0);
+
+  // Meta keys should be filled correctly.
+  // Note: sets are used here, but it is undefined behavior if
+  // the class has multiple componenets reporting overlapping tags.
+
+  // Get the expected tags = combined tags of all components.
+  std::set<int32_t> static_tags(static_tags_1.begin(), static_tags_1.end());
+  static_tags.insert(static_tags_2.begin(), static_tags_2.end());
+  std::set<int32_t> control_tags(control_tags_1.begin(), control_tags_1.end());
+  control_tags.insert(control_tags_2.begin(), control_tags_2.end());
+  std::set<int32_t> dynamic_tags(dynamic_tags_1.begin(), dynamic_tags_1.end());
+  dynamic_tags.insert(dynamic_tags_2.begin(), dynamic_tags_2.end());
+
+  // Static tags includes not only all component static tags, but also
+  // the meta AVAILABLE_*_KEYS (* = [REQUEST, RESULT, CHARACTERISTICS]).
+  static_tags.emplace(ANDROID_REQUEST_AVAILABLE_REQUEST_KEYS);
+  static_tags.emplace(ANDROID_REQUEST_AVAILABLE_RESULT_KEYS);
+  static_tags.emplace(ANDROID_REQUEST_AVAILABLE_CHARACTERISTICS_KEYS);
+
+  // Check against what was filled in in the metadata.
+  metadata.acquire(metadata_raw);
+  CompareTags(static_tags,
+              metadata.find(ANDROID_REQUEST_AVAILABLE_CHARACTERISTICS_KEYS));
+  CompareTags(control_tags,
+              metadata.find(ANDROID_REQUEST_AVAILABLE_REQUEST_KEYS));
+  CompareTags(dynamic_tags,
+              metadata.find(ANDROID_REQUEST_AVAILABLE_RESULT_KEYS));
+}
+
+TEST_F(MetadataTest, FillStaticFail) {
+  camera_metadata_t* metadata = nullptr;
+  int err = -99;
+  // Order undefined, and may or may not exit early; use AtMost.
+  EXPECT_CALL(*component1_, PopulateStaticFields(_))
+      .Times(AtMost(1))
+      .WillOnce(Return(0));
+  EXPECT_CALL(*component2_, PopulateStaticFields(_)).WillOnce(Return(err));
+
+  // May or may not exit early, may still try to populate meta tags.
+  EXPECT_CALL(*component1_, StaticTags())
+      .Times(AtMost(1))
+      .WillOnce(ReturnRef(empty_tags_));
+  EXPECT_CALL(*component1_, ControlTags())
+      .Times(AtMost(1))
+      .WillOnce(ReturnRef(empty_tags_));
+  EXPECT_CALL(*component1_, DynamicTags())
+      .Times(AtMost(1))
+      .WillOnce(ReturnRef(empty_tags_));
+  EXPECT_CALL(*component2_, StaticTags())
+      .Times(AtMost(1))
+      .WillOnce(ReturnRef(empty_tags_));
+  EXPECT_CALL(*component2_, ControlTags())
+      .Times(AtMost(1))
+      .WillOnce(ReturnRef(empty_tags_));
+  EXPECT_CALL(*component2_, DynamicTags())
+      .Times(AtMost(1))
+      .WillOnce(ReturnRef(empty_tags_));
+
+  AddComponents();
+  // If any component errors, error should be returned
+  EXPECT_EQ(dut_->FillStaticMetadata(&metadata), err);
+}
+
+TEST_F(MetadataTest, IsValidSuccess) {
+  android::CameraMetadata metadata(1);
+
+  // Should check if all the component request values are valid.
+  EXPECT_CALL(*component1_, SupportsRequestValues(_)).WillOnce(Return(true));
+  EXPECT_CALL(*component2_, SupportsRequestValues(_)).WillOnce(Return(true));
+
+  AddComponents();
+  // Should succeed.
+  // Note: getAndLock is a lock against pointer invalidation, not concurrency,
+  // and unlocks on object destruction.
+  EXPECT_TRUE(dut_->IsValidRequest(metadata.getAndLock()));
+}
+
+TEST_F(MetadataTest, IsValidFail) {
+  android::CameraMetadata metadata(1);
+
+  // Should check if all the component request values are valid.
+  // Order undefined, and may or may not exit early; use AtMost.
+  EXPECT_CALL(*component1_, SupportsRequestValues(_))
+      .Times(AtMost(1))
+      .WillOnce(Return(true));
+  EXPECT_CALL(*component2_, SupportsRequestValues(_)).WillOnce(Return(false));
+
+  AddComponents();
+  // Should fail since one of the components failed.
+  // Note: getAndLock is a lock against pointer invalidation, not concurrency,
+  // and unlocks on object destruction.
+  EXPECT_FALSE(dut_->IsValidRequest(metadata.getAndLock()));
+}
+
+TEST_F(MetadataTest, IsValidNull) {
+  camera_metadata_t* metadata = nullptr;
+
+  // Setting null settings is a special case indicating to use the
+  // previous (valid) settings. As such it is inherently valid.
+  // Should not try to check any components.
+  EXPECT_CALL(*component1_, SupportsRequestValues(_)).Times(0);
+  EXPECT_CALL(*component2_, SupportsRequestValues(_)).Times(0);
+
+  AddComponents();
+  EXPECT_TRUE(dut_->IsValidRequest(metadata));
+}
+
+TEST_F(MetadataTest, SetSettingsSuccess) {
+  android::CameraMetadata metadata(1);
+
+  // Should check if all the components set successfully.
+  EXPECT_CALL(*component1_, SetRequestValues(_)).WillOnce(Return(0));
+  EXPECT_CALL(*component2_, SetRequestValues(_)).WillOnce(Return(0));
+
+  AddComponents();
+  // Should succeed.
+  // Note: getAndLock is a lock against pointer invalidation, not concurrency,
+  // and unlocks on object destruction.
+  EXPECT_EQ(dut_->SetRequestSettings(metadata.getAndLock()), 0);
+}
+
+TEST_F(MetadataTest, SetSettingsFail) {
+  android::CameraMetadata metadata(1);
+  int err = -99;
+
+  // Should check if all the components set successfully.
+  // Order undefined, and may or may not exit early; use AtMost.
+  EXPECT_CALL(*component1_, SetRequestValues(_))
+      .Times(AtMost(1))
+      .WillOnce(Return(0));
+  EXPECT_CALL(*component2_, SetRequestValues(_)).WillOnce(Return(err));
+
+  AddComponents();
+  // Should fail since one of the components failed.
+  // Note: getAndLock is a lock against pointer invalidation, not concurrency,
+  // and unlocks on object destruction.
+  EXPECT_EQ(dut_->SetRequestSettings(metadata.getAndLock()), err);
+}
+
+TEST_F(MetadataTest, SetSettingsNull) {
+  camera_metadata_t* metadata = nullptr;
+
+  // Setting null settings is a special case indicating to use the
+  // previous settings. Should not try to set any components.
+  EXPECT_CALL(*component1_, SetRequestValues(_)).Times(0);
+  EXPECT_CALL(*component2_, SetRequestValues(_)).Times(0);
+
+  AddComponents();
+  // Should succeed.
+  EXPECT_EQ(dut_->SetRequestSettings(metadata), 0);
+}
+
+TEST_F(MetadataTest, FillResultSuccess) {
+  camera_metadata_t* metadata = nullptr;
+
+  // Should check if all the components fill results successfully.
+  EXPECT_CALL(*component1_, PopulateDynamicFields(_)).WillOnce(Return(0));
+  EXPECT_CALL(*component2_, PopulateDynamicFields(_)).WillOnce(Return(0));
+
+  AddComponents();
+  // Should succeed.
+  EXPECT_EQ(dut_->FillResultMetadata(&metadata), 0);
+}
+
+TEST_F(MetadataTest, FillResultFail) {
+  camera_metadata_t* metadata = nullptr;
+  int err = -99;
+
+  // Should check if all the components fill results successfully.
+  // Order undefined, and may or may not exit early; use AtMost.
+  EXPECT_CALL(*component1_, PopulateDynamicFields(_))
+      .Times(AtMost(1))
+      .WillOnce(Return(0));
+  EXPECT_CALL(*component2_, PopulateDynamicFields(_)).WillOnce(Return(err));
+
+  AddComponents();
+  // Should fail since one of the components failed.
+  EXPECT_EQ(dut_->FillResultMetadata(&metadata), err);
+}
+
+}  // namespace v4l2_camera_hal