Add the ability to load a new database file into an existing cache (#16)

* Add the ability to load a new database file into an existing cache

* Add comment about add_database possibly invalidating iterators in namespace_members

src/impl/winmd_reader/cache.h

@@ -35,34 +35,7 @@ namespace winmd::reader
             {
                 for (auto&&[name, type] : members.types)
                 {
-                    switch (get_category(type))
-                    {
-                    case category::interface_type:
-                        members.interfaces.push_back(type);
-                        continue;
-                    case category::class_type:
-                        if (extends_type(type, "System"sv, "Attribute"sv))
-                        {
-                            members.attributes.push_back(type);
-                            continue;
-                        }
-                        members.classes.push_back(type);
-                        continue;
-                    case category::enum_type:
-                        members.enums.push_back(type);
-                        continue;
-                    case category::struct_type:
-                        if (get_attribute(type, "Windows.Foundation.Metadata"sv, "ApiContractAttribute"sv))
-                        {
-                            members.contracts.push_back(type);
-                            continue;
-                        }
-                        members.structs.push_back(type);
-                        continue;
-                    case category::delegate_type:
-                        members.delegates.push_back(type);
-                        continue;
-                    }
+                    add_type_to_members(type, members);
                 }
             }
         }
@@ -165,6 +138,32 @@ namespace winmd::reader
             remove(members.delegates, name);
         }
 
+        // This won't invalidate any existing database or row_base (e.g. TypeDef) instances
+        // However, it may invalidate iterators and references to namespace_members, because those are stored in std::vector
+        void add_database(std::string_view const& file)
+        {
+            auto& db = m_databases.emplace_back(file, this);
+            for (auto&& type : db.TypeDef)
+            {
+                if (type.Flags().value == 0 || is_nested(type))
+                {
+                    continue;
+                }
+
+                auto& ns = m_namespaces[type.TypeNamespace()];
+                auto[iter, inserted] = ns.types.try_emplace(type.TypeName(), type);
+                if (inserted)
+                {
+                    add_type_to_members(type, ns);
+                }
+            }
+
+            for (auto&& row : db.NestedClass)
+            {
+                m_nested_types[row.EnclosingType()].push_back(row.NestedType());
+            }
+        }
+
         std::vector<TypeDef> const& nested_types(TypeDef const& enclosing_type) const
         {
             auto it = m_nested_types.find(enclosing_type);
@@ -195,6 +194,38 @@ namespace winmd::reader
 
     private:
 
+        void add_type_to_members(TypeDef const& type, namespace_members& members)
+        {
+            switch (get_category(type))
+            {
+            case category::interface_type:
+                members.interfaces.push_back(type);
+                return;
+            case category::class_type:
+                if (extends_type(type, "System"sv, "Attribute"sv))
+                {
+                    members.attributes.push_back(type);
+                    return;
+                }
+                members.classes.push_back(type);
+                return;
+            case category::enum_type:
+                members.enums.push_back(type);
+                return;
+            case category::struct_type:
+                if (get_attribute(type, "Windows.Foundation.Metadata"sv, "ApiContractAttribute"sv))
+                {
+                    members.contracts.push_back(type);
+                    return;
+                }
+                members.structs.push_back(type);
+                return;
+            case category::delegate_type:
+                members.delegates.push_back(type);
+                return;
+            }
+        }
+
         std::list<database> m_databases;
         std::map<std::string_view, namespace_members> m_namespaces;
         std::map<TypeDef, std::vector<TypeDef>> m_nested_types;

test/cache.cpp

@@ -0,0 +1,89 @@
+#include "pch.h"
+#include <winmd_reader.h>
+
+using namespace winmd::reader;
+
+TEST_CASE("cache_add_invalidate")
+{
+    std::array<char, 260> local{};
+
+#ifdef _WIN64
+    ExpandEnvironmentStringsA("%windir%\\System32\\WinMetadata", local.data(), static_cast<uint32_t>(local.size()));
+#else
+    ExpandEnvironmentStringsA("%windir%\\SysNative\\WinMetadata", local.data(), static_cast<uint32_t>(local.size()));
+#endif
+
+    std::filesystem::path winmd_dir = local.data();
+    auto file_path = winmd_dir;
+    file_path.append("Windows.Foundation.winmd");
+
+    cache c(file_path.string());
+
+    // Get a type and a database and verify that neither are invalidated by adding a new db
+    TypeDef IStringable = c.find("Windows.Foundation", "IStringable");
+    auto const db = &(c.databases().front());
+
+    file_path = winmd_dir;
+    file_path.append("Windows.Data.winmd");
+    c.add_database(file_path.string());
+
+    TypeDef IStringable2 = c.find("Windows.Foundation", "IStringable");
+    REQUIRE(IStringable == IStringable2);
+
+    auto const db2 = &(c.databases().front());
+    REQUIRE(db == db2);
+}
+
+TEST_CASE("cache_add")
+{
+    std::array<char, 260> local{};
+
+#ifdef _WIN64
+    ExpandEnvironmentStringsA("%windir%\\System32\\WinMetadata", local.data(), static_cast<uint32_t>(local.size()));
+#else
+    ExpandEnvironmentStringsA("%windir%\\SysNative\\WinMetadata", local.data(), static_cast<uint32_t>(local.size()));
+#endif
+
+    std::filesystem::path winmd_dir = local.data();
+    auto file_path = winmd_dir;
+    file_path.append("Windows.Foundation.winmd");
+
+    cache c(file_path.string());
+
+    TypeDef JsonValue = c.find("Windows.Data.Json", "JsonValue");
+    REQUIRE(!JsonValue);
+
+    file_path = winmd_dir;
+    file_path.append("Windows.Data.winmd");
+    c.add_database(file_path.string());
+
+    JsonValue = c.find("Windows.Data.Json", "JsonValue");
+    REQUIRE(!!JsonValue);
+    REQUIRE(JsonValue.TypeName() == "JsonValue");
+    REQUIRE(JsonValue.TypeNamespace() == "Windows.Data.Json");
+}
+
+TEST_CASE("cache_add_duplicate")
+{
+    std::array<char, 260> local{};
+
+#ifdef _WIN64
+    ExpandEnvironmentStringsA("%windir%\\System32\\WinMetadata", local.data(), static_cast<uint32_t>(local.size()));
+#else
+    ExpandEnvironmentStringsA("%windir%\\SysNative\\WinMetadata", local.data(), static_cast<uint32_t>(local.size()));
+#endif
+
+    std::filesystem::path winmd_dir = local.data();
+    auto file_path = winmd_dir;
+    file_path.append("Windows.Foundation.winmd");
+
+    cache c(file_path.string());
+
+    TypeDef IStringable = c.find("Windows.Foundation", "IStringable");
+
+    // Add a winmd with duplicate types, and verify the original types aren't invalidated.
+    c.add_database(file_path.string());
+
+    TypeDef IStringable2 = c.find("Windows.Foundation", "IStringable");
+    REQUIRE(IStringable == IStringable2);
+}

test/winmd.vcxproj

@@ -19,6 +19,7 @@
     </ProjectConfiguration>
   </ItemGroup>
   <ItemGroup>
+    <ClCompile Include="cache.cpp" />
     <ClCompile Include="database.cpp" />
     <ClCompile Include="main.cpp">
       <PrecompiledHeader Condition="'$(Configuration)|$(Platform)'=='Debug|Win32'">NotUsing</PrecompiledHeader>