Add HostService.data_dir

src/dusk/mod_loader.hpp

@@ -166,6 +166,8 @@ struct LoadedMod {
     std::filesystem::path dir;
     // Stable UTF-8 storage for HostService::mod_dir.
     std::string dirUtf8;
+    // Stable UTF-8 storage for HostService::data_dir.
+    std::string dataDirUtf8;
 
     uint32_t searchDirIndex = 0;
     // Native lib is dlopen'd in place and stays resident for the session. Reload is unsupported.

src/dusk/mods/svc/host.cpp

@@ -1,13 +1,17 @@
 #include "registry.hpp"
 #include "slot_map.hpp"
 
+#include "dusk/main.h"
 #include "dusk/mods/loader/loader.hpp"
+#include "dusk/mods/log_buffer.hpp"
 #include "dusk/mods/manifest.hpp"
 #include "fmt/format.h"
 
 #include <algorithm>
-#include <vector>
+#include <borealis/io.hpp>
 #include <borealis/version.h>
+#include <filesystem>
+#include <vector>
 
 namespace dusk::mods::svc {
 namespace {
@@ -68,6 +72,41 @@ const char* host_native_dir(ModContext* context) {
     return mod != nullptr ? mod->nativeDirUtf8.c_str() : "";
 }
 
+ModResult host_data_dir(ModContext* context, const char** outPath) {
+    if (outPath == nullptr) {
+        return MOD_INVALID_ARGUMENT;
+    }
+    *outPath = nullptr;
+
+    auto* mod = mod_from_context(context);
+    if (mod == nullptr) {
+        return MOD_INVALID_ARGUMENT;
+    }
+
+    if (mod->dataDirUtf8.empty()) {
+        namespace fs = std::filesystem;
+        std::error_code ec;
+        const fs::path path = fs::absolute(dusk::ConfigPath / "mod_data" / mod->metadata.id, ec);
+        if (ec) {
+            log::write(mod->metadata.id, LOG_LEVEL_ERROR,
+                "failed to resolve persistent mod data directory: {}", ec.message());
+            return MOD_ERROR;
+        }
+
+        fs::create_directories(path, ec);
+        if (ec) {
+            log::write(mod->metadata.id, LOG_LEVEL_ERROR,
+                "failed to create persistent mod data directory {}: {}",
+                borealis::io::fs_path_to_string(path), ec.message());
+            return MOD_ERROR;
+        }
+        mod->dataDirUtf8 = borealis::io::fs_path_to_string(path);
+    }
+
+    *outPath = mod->dataDirUtf8.c_str();
+    return MOD_OK;
+}
+
 struct LifecycleWatcher {
     ModLifecycleFn fn = nullptr;
     void* userData = nullptr;
@@ -148,6 +187,7 @@ constinit HostService s_hostService{
     .watch_mod_lifecycle = host_watch_mod_lifecycle,
     .unwatch_mod_lifecycle = host_unwatch_mod_lifecycle,
     .native_dir = host_native_dir,
+    .data_dir = host_data_dir,
 };
 
 }  // namespace