6 files changed, 102 insertions, 20 deletions

diff --git a/src/core/file_sys/fsmitm_romfsbuild.cpp b/src/core/file_sys/fsmitm_romfsbuild.cpp
index d126ae8dd..2aff2708a 100644
--- a/src/core/file_sys/fsmitm_romfsbuild.cpp
+++ b/src/core/file_sys/fsmitm_romfsbuild.cpp
@@ -240,7 +240,7 @@ RomFSBuildContext::RomFSBuildContext(VirtualDir base_, VirtualDir ext_)
 
 RomFSBuildContext::~RomFSBuildContext() = default;
 
-std::map<u64, VirtualFile> RomFSBuildContext::Build() {
+std::multimap<u64, VirtualFile> RomFSBuildContext::Build() {
     const u64 dir_hash_table_entry_count = romfs_get_hash_table_count(num_dirs);
     const u64 file_hash_table_entry_count = romfs_get_hash_table_count(num_files);
     dir_hash_table_size = 4 * dir_hash_table_entry_count;
@@ -294,7 +294,7 @@ std::map<u64, VirtualFile> RomFSBuildContext::Build() {
         cur_dir->parent->child = cur_dir;
     }
 
-    std::map<u64, VirtualFile> out;
+    std::multimap<u64, VirtualFile> out;
 
     // Populate file tables.
     for (const auto& it : files) {
diff --git a/src/core/file_sys/fsmitm_romfsbuild.h b/src/core/file_sys/fsmitm_romfsbuild.h
index a62502193..049de180b 100644
--- a/src/core/file_sys/fsmitm_romfsbuild.h
+++ b/src/core/file_sys/fsmitm_romfsbuild.h
@@ -43,7 +43,7 @@ public:
     ~RomFSBuildContext();
 
     // This finalizes the context.
-    std::map<u64, VirtualFile> Build();
+    std::multimap<u64, VirtualFile> Build();
 
 private:
     VirtualDir base;
diff --git a/src/core/file_sys/registered_cache.cpp b/src/core/file_sys/registered_cache.cpp
index 27c1b0233..37351c561 100644
--- a/src/core/file_sys/registered_cache.cpp
+++ b/src/core/file_sys/registered_cache.cpp
@@ -547,6 +547,56 @@ InstallResult RegisteredCache::InstallEntry(const XCI& xci, bool overwrite_if_ex
     return InstallEntry(*xci.GetSecurePartitionNSP(), overwrite_if_exists, copy);
 }
 
+bool RegisteredCache::RemoveExistingEntry(u64 title_id) {
+    const auto delete_nca = [this](const NcaID& id) {
+        const auto path = GetRelativePathFromNcaID(id, false, true, false);
+
+        if (dir->GetFileRelative(path) == nullptr) {
+            return false;
+        }
+
+        Core::Crypto::SHA256Hash hash{};
+        mbedtls_sha256_ret(id.data(), id.size(), hash.data(), 0);
+        const auto dirname = fmt::format("000000{:02X}", hash[0]);
+
+        const auto dir2 = GetOrCreateDirectoryRelative(dir, dirname);
+
+        const auto res = dir2->DeleteFile(fmt::format("{}.nca", Common::HexToString(id, false)));
+
+        return res;
+    };
+
+    // If an entry exists in the registered cache, remove it
+    if (HasEntry(title_id, ContentRecordType::Meta)) {
+        LOG_INFO(Loader,
+                 "Previously installed entry (v{}) for title_id={:016X} detected! "
+                 "Attempting to remove...",
+                 GetEntryVersion(title_id).value_or(0), title_id);
+        // Get all the ncas associated with the current CNMT and delete them
+        const auto meta_old_id =
+            GetNcaIDFromMetadata(title_id, ContentRecordType::Meta).value_or(NcaID{});
+        const auto program_id =
+            GetNcaIDFromMetadata(title_id, ContentRecordType::Program).value_or(NcaID{});
+        const auto data_id =
+            GetNcaIDFromMetadata(title_id, ContentRecordType::Data).value_or(NcaID{});
+        const auto control_id =
+            GetNcaIDFromMetadata(title_id, ContentRecordType::Control).value_or(NcaID{});
+        const auto html_id =
+            GetNcaIDFromMetadata(title_id, ContentRecordType::HtmlDocument).value_or(NcaID{});
+        const auto legal_id =
+            GetNcaIDFromMetadata(title_id, ContentRecordType::LegalInformation).value_or(NcaID{});
+
+        delete_nca(meta_old_id);
+        delete_nca(program_id);
+        delete_nca(data_id);
+        delete_nca(control_id);
+        delete_nca(html_id);
+        delete_nca(legal_id);
+        return true;
+    }
+    return false;
+}
+
 InstallResult RegisteredCache::InstallEntry(const NSP& nsp, bool overwrite_if_exists,
                                             const VfsCopyFunction& copy) {
     const auto ncas = nsp.GetNCAsCollapsed();
@@ -560,31 +610,57 @@ InstallResult RegisteredCache::InstallEntry(const NSP& nsp, bool overwrite_if_ex
         return InstallResult::ErrorMetaFailed;
     }
 
-    // Install Metadata File
     const auto meta_id_raw = (*meta_iter)->GetName().substr(0, 32);
     const auto meta_id = Common::HexStringToArray<16>(meta_id_raw);
 
-    const auto res = RawInstallNCA(**meta_iter, copy, overwrite_if_exists, meta_id);
-    if (res != InstallResult::Success)
-        return res;
+    if ((*meta_iter)->GetSubdirectories().empty()) {
+        LOG_ERROR(Loader,
+                  "The file you are attempting to install does not contain a section0 within the "
+                  "metadata NCA and is therefore malformed. Verify that the file is valid.");
+        return InstallResult::ErrorMetaFailed;
+    }
 
-    // Install all the other NCAs
     const auto section0 = (*meta_iter)->GetSubdirectories()[0];
+
+    if (section0->GetFiles().empty()) {
+        LOG_ERROR(Loader,
+                  "The file you are attempting to install does not contain a CNMT within the "
+                  "metadata NCA and is therefore malformed. Verify that the file is valid.");
+        return InstallResult::ErrorMetaFailed;
+    }
+
     const auto cnmt_file = section0->GetFiles()[0];
     const CNMT cnmt(cnmt_file);
+
+    const auto title_id = cnmt.GetTitleID();
+    const auto result = RemoveExistingEntry(title_id);
+
+    // Install Metadata File
+    const auto res = RawInstallNCA(**meta_iter, copy, overwrite_if_exists, meta_id);
+    if (res != InstallResult::Success) {
+        return res;
+    }
+
+    // Install all the other NCAs
     for (const auto& record : cnmt.GetContentRecords()) {
         // Ignore DeltaFragments, they are not useful to us
-        if (record.type == ContentRecordType::DeltaFragment)
+        if (record.type == ContentRecordType::DeltaFragment) {
             continue;
+        }
         const auto nca = GetNCAFromNSPForID(nsp, record.nca_id);
-        if (nca == nullptr)
+        if (nca == nullptr) {
             return InstallResult::ErrorCopyFailed;
+        }
         const auto res2 = RawInstallNCA(*nca, copy, overwrite_if_exists, record.nca_id);
-        if (res2 != InstallResult::Success)
+        if (res2 != InstallResult::Success) {
             return res2;
+        }
     }
 
     Refresh();
+    if (result) {
+        return InstallResult::OverwriteExisting;
+    }
     return InstallResult::Success;
 }
 
@@ -610,8 +686,9 @@ InstallResult RegisteredCache::InstallEntry(const NCA& nca, TitleType type,
     mbedtls_sha256_ret(data.data(), data.size(), c_rec.hash.data(), 0);
     memcpy(&c_rec.nca_id, &c_rec.hash, 16);
     const CNMT new_cnmt(header, opt_header, {c_rec}, {});
-    if (!RawInstallYuzuMeta(new_cnmt))
+    if (!RawInstallYuzuMeta(new_cnmt)) {
         return InstallResult::ErrorMetaFailed;
+    }
     return RawInstallNCA(nca, copy, overwrite_if_exists, c_rec.nca_id);
 }
 
@@ -649,8 +726,9 @@ InstallResult RegisteredCache::RawInstallNCA(const NCA& nca, const VfsCopyFuncti
     }
 
     auto out = dir->CreateFileRelative(path);
-    if (out == nullptr)
+    if (out == nullptr) {
         return InstallResult::ErrorCopyFailed;
+    }
     return copy(in, out, VFS_RC_LARGE_COPY_BLOCK) ? InstallResult::Success
                                                   : InstallResult::ErrorCopyFailed;
 }
diff --git a/src/core/file_sys/registered_cache.h b/src/core/file_sys/registered_cache.h
index f339cd17b..29cf0d40c 100644
--- a/src/core/file_sys/registered_cache.h
+++ b/src/core/file_sys/registered_cache.h
@@ -34,6 +34,7 @@ using VfsCopyFunction = std::function<bool(const VirtualFile&, const VirtualFile
 
 enum class InstallResult {
     Success,
+    OverwriteExisting,
     ErrorAlreadyExists,
     ErrorCopyFailed,
     ErrorMetaFailed,
@@ -154,6 +155,9 @@ public:
         std::optional<TitleType> title_type = {}, std::optional<ContentRecordType> record_type = {},
         std::optional<u64> title_id = {}) const override;
 
+    // Removes an existing entry based on title id
+    bool RemoveExistingEntry(u64 title_id);
+
     // Raw copies all the ncas from the xci/nsp to the csache. Does some quick checks to make sure
     // there is a meta NCA and all of them are accessible.
     InstallResult InstallEntry(const XCI& xci, bool overwrite_if_exists = false,
diff --git a/src/core/file_sys/vfs_concat.cpp b/src/core/file_sys/vfs_concat.cpp
index 16d801c0c..e0ff70174 100644
--- a/src/core/file_sys/vfs_concat.cpp
+++ b/src/core/file_sys/vfs_concat.cpp
@@ -11,7 +11,7 @@
 
 namespace FileSys {
 
-static bool VerifyConcatenationMapContinuity(const std::map<u64, VirtualFile>& map) {
+static bool VerifyConcatenationMapContinuity(const std::multimap<u64, VirtualFile>& map) {
     const auto last_valid = --map.end();
     for (auto iter = map.begin(); iter != last_valid;) {
         const auto old = iter++;
@@ -27,12 +27,12 @@ ConcatenatedVfsFile::ConcatenatedVfsFile(std::vector<VirtualFile> files_, std::s
     : name(std::move(name)) {
     std::size_t next_offset = 0;
     for (const auto& file : files_) {
-        files[next_offset] = file;
+        files.emplace(next_offset, file);
         next_offset += file->GetSize();
     }
 }
 
-ConcatenatedVfsFile::ConcatenatedVfsFile(std::map<u64, VirtualFile> files_, std::string name)
+ConcatenatedVfsFile::ConcatenatedVfsFile(std::multimap<u64, VirtualFile> files_, std::string name)
     : files(std::move(files_)), name(std::move(name)) {
     ASSERT(VerifyConcatenationMapContinuity(files));
 }
@@ -50,7 +50,7 @@ VirtualFile ConcatenatedVfsFile::MakeConcatenatedFile(std::vector<VirtualFile> f
 }
 
 VirtualFile ConcatenatedVfsFile::MakeConcatenatedFile(u8 filler_byte,
-                                                      std::map<u64, VirtualFile> files,
+                                                      std::multimap<u64, VirtualFile> files,
                                                       std::string name) {
     if (files.empty())
         return nullptr;
diff --git a/src/core/file_sys/vfs_concat.h b/src/core/file_sys/vfs_concat.h
index c90f9d5d1..7a26343c0 100644
--- a/src/core/file_sys/vfs_concat.h
+++ b/src/core/file_sys/vfs_concat.h
@@ -15,7 +15,7 @@ namespace FileSys {
 // read-only.
 class ConcatenatedVfsFile : public VfsFile {
     ConcatenatedVfsFile(std::vector<VirtualFile> files, std::string name);
-    ConcatenatedVfsFile(std::map<u64, VirtualFile> files, std::string name);
+    ConcatenatedVfsFile(std::multimap<u64, VirtualFile> files, std::string name);
 
 public:
     ~ConcatenatedVfsFile() override;
@@ -25,7 +25,7 @@ public:
 
     /// Convenience function that turns a map of offsets to files into a concatenated file, filling
     /// gaps with a given filler byte.
-    static VirtualFile MakeConcatenatedFile(u8 filler_byte, std::map<u64, VirtualFile> files,
+    static VirtualFile MakeConcatenatedFile(u8 filler_byte, std::multimap<u64, VirtualFile> files,
                                             std::string name);
 
     std::string GetName() const override;
@@ -40,7 +40,7 @@ public:
 
 private:
     // Maps starting offset to file -- more efficient.
-    std::map<u64, VirtualFile> files;
+    std::multimap<u64, VirtualFile> files;
     std::string name;
 };