patch_manager: Return a std::unique_ptr from ParseControlNCA() and GetControlMetadata() instead of a std::shared_ptr

Neither of these functions require the use of shared ownership of the
returned pointer. This makes it more difficult to create reference
cycles with, and makes the interface more generic, as std::shared_ptr
instances can be created from a std::unique_ptr, but the vice-versa
isn't possible. This also alters relevant functions to take NCA
arguments by const reference rather than a const reference to a
std::shared_ptr. These functions don't alter the ownership of the memory
used by the NCA instance, so we can make the interface more generic by
not assuming anything about the type of smart pointer the NCA is
contained within and make it the caller's responsibility to ensure the
supplied NCA is valid.

2 files changed, 9 insertions, 11 deletions

diff --git a/src/core/file_sys/patch_manager.cpp b/src/core/file_sys/patch_manager.cpp
index b14d7cb0a..019caebe9 100644
--- a/src/core/file_sys/patch_manager.cpp
+++ b/src/core/file_sys/patch_manager.cpp
@@ -345,23 +345,22 @@ std::map<std::string, std::string, std::less<>> PatchManager::GetPatchVersionNam
     return out;
 }
 
-std::pair<std::shared_ptr<NACP>, VirtualFile> PatchManager::GetControlMetadata() const {
+std::pair<std::unique_ptr<NACP>, VirtualFile> PatchManager::GetControlMetadata() const {
     const auto& installed{Service::FileSystem::GetUnionContents()};
 
     const auto base_control_nca = installed->GetEntry(title_id, ContentRecordType::Control);
     if (base_control_nca == nullptr)
         return {};
 
-    return ParseControlNCA(base_control_nca);
+    return ParseControlNCA(*base_control_nca);
 }
 
-std::pair<std::shared_ptr<NACP>, VirtualFile> PatchManager::ParseControlNCA(
-    const std::shared_ptr<NCA>& nca) const {
-    const auto base_romfs = nca->GetRomFS();
+std::pair<std::unique_ptr<NACP>, VirtualFile> PatchManager::ParseControlNCA(const NCA& nca) const {
+    const auto base_romfs = nca.GetRomFS();
     if (base_romfs == nullptr)
         return {};
 
-    const auto romfs = PatchRomFS(base_romfs, nca->GetBaseIVFCOffset(), ContentRecordType::Control);
+    const auto romfs = PatchRomFS(base_romfs, nca.GetBaseIVFCOffset(), ContentRecordType::Control);
     if (romfs == nullptr)
         return {};
 
@@ -373,7 +372,7 @@ std::pair<std::shared_ptr<NACP>, VirtualFile> PatchManager::ParseControlNCA(
     if (nacp_file == nullptr)
         nacp_file = extracted->GetFile("Control.nacp");
 
-    const auto nacp = nacp_file == nullptr ? nullptr : std::make_shared<NACP>(nacp_file);
+    auto nacp = nacp_file == nullptr ? nullptr : std::make_unique<NACP>(nacp_file);
 
     VirtualFile icon_file;
     for (const auto& language : FileSys::LANGUAGE_NAMES) {
@@ -382,6 +381,6 @@ std::pair<std::shared_ptr<NACP>, VirtualFile> PatchManager::ParseControlNCA(
             break;
     }
 
-    return {nacp, icon_file};
+    return {std::move(nacp), icon_file};
 }
 } // namespace FileSys
diff --git a/src/core/file_sys/patch_manager.h b/src/core/file_sys/patch_manager.h
index eb6fc4607..7d168837f 100644
--- a/src/core/file_sys/patch_manager.h
+++ b/src/core/file_sys/patch_manager.h
@@ -57,11 +57,10 @@ public:
 
     // Given title_id of the program, attempts to get the control data of the update and parse it,
     // falling back to the base control data.
-    std::pair<std::shared_ptr<NACP>, VirtualFile> GetControlMetadata() const;
+    std::pair<std::unique_ptr<NACP>, VirtualFile> GetControlMetadata() const;
 
     // Version of GetControlMetadata that takes an arbitrary NCA
-    std::pair<std::shared_ptr<NACP>, VirtualFile> ParseControlNCA(
-        const std::shared_ptr<NCA>& nca) const;
+    std::pair<std::unique_ptr<NACP>, VirtualFile> ParseControlNCA(const NCA& nca) const;
 
 private:
     u64 title_id;