Add AndroidBuild implementation based on misc_info.txt

Bug: b/471081721

Author: Databean

base/cvd/cuttlefish/host/commands/assemble_cvd/android_build/BUILD.bazel

@@ -64,3 +64,16 @@ cf_cc_library(
         "@protobuf",
     ],
 )
+
+cf_cc_library(
+    name = "misc_info_metadata",
+    srcs = ["misc_info_metadata.cc"],
+    hdrs = ["misc_info_metadata.h"],
+    deps = [
+        "//cuttlefish/host/commands/assemble_cvd/android_build",
+        "//cuttlefish/result",
+        "@abseil-cpp//absl/strings",
+        "@abseil-cpp//absl/strings:str_format",
+        "@fmt",
+    ],
+)

base/cvd/cuttlefish/host/commands/assemble_cvd/android_build/misc_info_metadata.cc

@@ -0,0 +1,113 @@
+//
+// 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.
+
+#include "cuttlefish/host/commands/assemble_cvd/android_build/misc_info_metadata.h"
+
+#include <functional>
+#include <map>
+#include <memory>
+#include <ostream>
+#include <set>
+#include <string>
+#include <string_view>
+#include <utility>
+
+#include "absl/strings/match.h"
+#include "absl/strings/str_cat.h"
+#include "absl/strings/str_split.h"
+#include "fmt/ostream.h"
+
+#include "cuttlefish/host/commands/assemble_cvd/android_build/android_build.h"
+#include "cuttlefish/result/result.h"
+
+namespace cuttlefish {
+namespace {
+
+class MetadataFromMiscInfo : public AndroidBuild {
+ public:
+  MetadataFromMiscInfo(std::map<std::string, std::string> misc_info)
+      : misc_info_(std::move(misc_info)) {}
+
+  Result<std::set<std::string, std::less<void>>> SystemPartitions() override {
+    return CF_EXPECT(PartitionsMatchingGroup("system"));
+  }
+
+  Result<std::set<std::string, std::less<void>>> VendorPartitions() override {
+    return CF_EXPECT(PartitionsMatchingGroup("vendor"));
+  }
+
+  Result<std::set<std::string, std::less<void>>> LogicalPartitions() override {
+    std::set<std::string, std::less<void>> partitions;
+    partitions.merge(CF_EXPECT(SystemPartitions()));
+    partitions.merge(CF_EXPECT(VendorPartitions()));
+    return partitions;
+  }
+
+ private:
+  Result<std::set<std::string, std::less<void>>> PartitionsMatchingGroup(
+      std::string_view match) {
+    std::string groups_key = "super_partition_groups";
+    auto groups_it = misc_info_.find(groups_key);
+    CF_EXPECTF(groups_it != misc_info_.end(), "Could not find entry for '{}'",
+               groups_key);
+
+    std::string_view matching_group;
+    for (std::string_view group :
+         absl::StrSplit(groups_it->second, " ", absl::SkipEmpty())) {
+      if (absl::StrContains(group, match)) {
+        matching_group = group;
+      }
+    }
+
+    CF_EXPECTF(!matching_group.empty(), "No '{}' group", match);
+
+    std::string key = absl::StrCat("super_", matching_group, "_partition_list");
+
+    auto group_it = misc_info_.find(key);
+    CF_EXPECTF(group_it != misc_info_.end(), "Could not find entry for '{}'",
+               key);
+
+    return absl::StrSplit(group_it->second, " ", absl::SkipEmpty());
+  }
+
+  std::ostream& Format(std::ostream& out) const override {
+    out << "MetadataFromMiscInfo { ";
+    for (auto& [key, value] : misc_info_) {
+      fmt::print(out, "'{}' => '{}', ", key, value);
+    }
+    return out << "}";
+  }
+
+  std::map<std::string, std::string> misc_info_;
+};
+
+}  // namespace
+
+Result<std::unique_ptr<AndroidBuild>> AndroidBuildFromMiscInfo(
+    std::map<std::string, std::string> misc_info) {
+  auto build = std::make_unique<MetadataFromMiscInfo>(std::move(misc_info));
+
+  std::set<std::string, std::less<void>> system =
+      CF_EXPECT(build->SystemPartitions());
+  CF_EXPECT(!system.empty());
+
+  std::set<std::string, std::less<void>> vendor =
+      CF_EXPECT(build->VendorPartitions());
+  CF_EXPECT(!vendor.empty());
+
+  return build;
+}
+
+}  // namespace cuttlefish

base/cvd/cuttlefish/host/commands/assemble_cvd/android_build/misc_info_metadata.h

@@ -0,0 +1,39 @@
+//
+// 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 <map>
+#include <memory>
+#include <string>
+
+#include "cuttlefish/host/commands/assemble_cvd/android_build/android_build.h"
+#include "cuttlefish/result/result.h"
+
+namespace cuttlefish {
+
+/**
+ * Reports partition information from the key-value pairs in a `misc_info.txt`
+ * file.
+ *
+ * Although `misc_info.txt` does not contain any image files, it does have a
+ * complete list of the logical partitions that are intended to be present in a
+ * complete `super.img` file, as well as the division between "system" and
+ * "vendor" side logical partitions.
+ */
+Result<std::unique_ptr<AndroidBuild>> AndroidBuildFromMiscInfo(
+    std::map<std::string, std::string>);
+
+}  // namespace cuttlefish