7 files changed, 48 insertions, 7 deletions

diff --git a/src/core/file_sys/bis_factory.cpp b/src/core/file_sys/bis_factory.cpp
index 76a2b7e86..e29f70b3a 100644
--- a/src/core/file_sys/bis_factory.cpp
+++ b/src/core/file_sys/bis_factory.cpp
@@ -8,8 +8,9 @@
 
 namespace FileSys {
 
-BISFactory::BISFactory(VirtualDir nand_root_, VirtualDir load_root_)
+BISFactory::BISFactory(VirtualDir nand_root_, VirtualDir load_root_, VirtualDir dump_root_)
     : nand_root(std::move(nand_root_)), load_root(std::move(load_root_)),
+      dump_root(std::move(dump_root_)),
       sysnand_cache(std::make_unique<RegisteredCache>(
           GetOrCreateDirectoryRelative(nand_root, "/system/Contents/registered"))),
       usrnand_cache(std::make_unique<RegisteredCache>(
@@ -32,4 +33,10 @@ VirtualDir BISFactory::GetModificationLoadRoot(u64 title_id) const {
     return GetOrCreateDirectoryRelative(load_root, fmt::format("/{:016X}", title_id));
 }
 
+VirtualDir BISFactory::GetModificationDumpRoot(u64 title_id) const {
+    if (title_id == 0)
+        return nullptr;
+    return GetOrCreateDirectoryRelative(dump_root, fmt::format("/{:016X}", title_id));
+}
+
 } // namespace FileSys
diff --git a/src/core/file_sys/bis_factory.h b/src/core/file_sys/bis_factory.h
index 364d309bd..453c11ad2 100644
--- a/src/core/file_sys/bis_factory.h
+++ b/src/core/file_sys/bis_factory.h
@@ -17,17 +17,19 @@ class RegisteredCache;
 /// registered caches.
 class BISFactory {
 public:
-    explicit BISFactory(VirtualDir nand_root, VirtualDir load_root);
+    explicit BISFactory(VirtualDir nand_root, VirtualDir load_root, VirtualDir dump_root);
     ~BISFactory();
 
     RegisteredCache* GetSystemNANDContents() const;
     RegisteredCache* GetUserNANDContents() const;
 
     VirtualDir GetModificationLoadRoot(u64 title_id) const;
+    VirtualDir GetModificationDumpRoot(u64 title_id) const;
 
 private:
     VirtualDir nand_root;
     VirtualDir load_root;
+    VirtualDir dump_root;
 
     std::unique_ptr<RegisteredCache> sysnand_cache;
     std::unique_ptr<RegisteredCache> usrnand_cache;
diff --git a/src/core/file_sys/patch_manager.cpp b/src/core/file_sys/patch_manager.cpp
index 0c1156989..8d062eb3e 100644
--- a/src/core/file_sys/patch_manager.cpp
+++ b/src/core/file_sys/patch_manager.cpp
@@ -19,6 +19,7 @@
 #include "core/file_sys/vfs_vector.h"
 #include "core/hle/service/filesystem/filesystem.h"
 #include "core/loader/loader.h"
+#include "core/settings.h"
 
 namespace FileSys {
 
@@ -119,6 +120,18 @@ std::vector<u8> PatchManager::PatchNSO(const std::vector<u8>& nso) const {
     const auto build_id_raw = Common::HexArrayToString(header.build_id);
     const auto build_id = build_id_raw.substr(0, build_id_raw.find_last_not_of('0') + 1);
 
+    if (Settings::values.dump_nso) {
+        LOG_INFO(Loader, "Dumping NSO for build_id={}, title_id={:016X}", build_id, title_id);
+        const auto dump_dir = Service::FileSystem::GetModificationDumpRoot(title_id);
+        if (dump_dir != nullptr) {
+            const auto nso_dir = GetOrCreateDirectoryRelative(dump_dir, "/nso");
+            const auto file = nso_dir->CreateFile(fmt::format("{}.nso", build_id));
+
+            file->Resize(nso.size());
+            file->WriteBytes(nso);
+        }
+    }
+
     LOG_INFO(Loader, "Patching NSO for build_id={}", build_id);
 
     const auto load_dir = Service::FileSystem::GetModificationLoadRoot(title_id);
diff --git a/src/core/hle/service/filesystem/filesystem.cpp b/src/core/hle/service/filesystem/filesystem.cpp
index ea8fd965a..a92cf7815 100644
--- a/src/core/hle/service/filesystem/filesystem.cpp
+++ b/src/core/hle/service/filesystem/filesystem.cpp
@@ -370,6 +370,15 @@ FileSys::VirtualDir GetModificationLoadRoot(u64 title_id) {
     return bis_factory->GetModificationLoadRoot(title_id);
 }
 
+FileSys::VirtualDir GetModificationDumpRoot(u64 title_id) {
+    LOG_TRACE(Service_FS, "Opening mod dump root for tid={:016X}", title_id);
+
+    if (bis_factory == nullptr)
+        return nullptr;
+
+    return bis_factory->GetModificationDumpRoot(title_id);
+}
+
 void CreateFactories(FileSys::VfsFilesystem& vfs, bool overwrite) {
     if (overwrite) {
         bis_factory = nullptr;
@@ -383,13 +392,21 @@ void CreateFactories(FileSys::VfsFilesystem& vfs, bool overwrite) {
                                           FileSys::Mode::ReadWrite);
     auto load_directory = vfs.OpenDirectory(FileUtil::GetUserPath(FileUtil::UserPath::LoadDir),
                                             FileSys::Mode::ReadWrite);
+    auto dump_directory = vfs.OpenDirectory(FileUtil::GetUserPath(FileUtil::UserPath::DumpDir),
+                                            FileSys::Mode::ReadWrite);
 
-    if (bis_factory == nullptr)
-        bis_factory = std::make_unique<FileSys::BISFactory>(nand_directory, load_directory);
-    if (save_data_factory == nullptr)
+    if (bis_factory == nullptr) {
+        bis_factory =
+            std::make_unique<FileSys::BISFactory>(nand_directory, load_directory, dump_directory);
+    }
+
+    if (save_data_factory == nullptr) {
         save_data_factory = std::make_unique<FileSys::SaveDataFactory>(std::move(nand_directory));
-    if (sdmc_factory == nullptr)
+    }
+
+    if (sdmc_factory == nullptr) {
         sdmc_factory = std::make_unique<FileSys::SDMCFactory>(std::move(sd_directory));
+    }
 }
 
 void InstallInterfaces(SM::ServiceManager& service_manager, FileSys::VfsFilesystem& vfs) {
diff --git a/src/core/hle/service/filesystem/filesystem.h b/src/core/hle/service/filesystem/filesystem.h
index 2cbb70c87..e38f02869 100644
--- a/src/core/hle/service/filesystem/filesystem.h
+++ b/src/core/hle/service/filesystem/filesystem.h
@@ -55,6 +55,7 @@ FileSys::RegisteredCache* GetUserNANDContents();
 FileSys::RegisteredCache* GetSDMCContents();
 
 FileSys::VirtualDir GetModificationLoadRoot(u64 title_id);
+FileSys::VirtualDir GetModificationDumpRoot(u64 title_id);
 
 // Creates the SaveData, SDMC, and BIS Factories. Should be called once and before any function
 // above is called.
diff --git a/src/core/loader/nso.cpp b/src/core/loader/nso.cpp
index 68efca5c0..aaf006309 100644
--- a/src/core/loader/nso.cpp
+++ b/src/core/loader/nso.cpp
@@ -154,7 +154,7 @@ std::optional<VAddr> AppLoader_NSO::LoadModule(const FileSys::VfsFile& file, VAd
     program_image.resize(image_size);
 
     // Apply patches if necessary
-    if (pm && pm->HasNSOPatch(nso_header.build_id)) {
+    if (pm && (pm->HasNSOPatch(nso_header.build_id) || Settings::values.dump_nso)) {
         std::vector<u8> pi_header(program_image.size() + 0x100);
         std::memcpy(pi_header.data(), &nso_header, sizeof(NsoHeader));
         std::memcpy(pi_header.data() + 0x100, program_image.data(), program_image.size());
diff --git a/src/core/settings.h b/src/core/settings.h
index 84dc5050b..e424479f2 100644
--- a/src/core/settings.h
+++ b/src/core/settings.h
@@ -159,6 +159,7 @@ struct Values {
     bool use_gdbstub;
     u16 gdbstub_port;
     std::string program_args;
+    bool dump_nso;
 
     // WebService
     bool enable_telemetry;