Add LoadableLibraryManager and refactor StimBuffApiManager to use it.

Centralize dlopen/search in LoadableLibraryManager so typed library managers
can share one loaded-shlib registry without duplicating load/unload logic.

Co-authored-by: Cursor <cursoragent@cursor.com>

smocore/include/loadableLib/loadableLibraryManager.h

@@ -0,0 +1,111 @@
+#ifndef LOADABLE_LIBRARY_MANAGER_H
+#define LOADABLE_LIBRARY_MANAGER_H
+
+#include <dlfcn.h>
+#include <atomic>
+#include <memory>
+#include <optional>
+#include <stdexcept>
+#include <string>
+#include <vector>
+#include <spinscale/co/coQutex.h>
+#include <spinscale/sharedResourceGroup.h>
+
+namespace smo {
+namespace loadable_lib {
+
+class LoadableLibraryManager
+{
+public:
+	struct SharedLibraryDeleter
+	{
+		void operator()(void* handle) const;
+	};
+
+	struct LoadedSharedLibrary
+	{
+		LoadedSharedLibrary(
+			std::string libraryPathIn,
+			std::string resolvedPathIn,
+			std::unique_ptr<void, SharedLibraryDeleter> dlopenHandleIn)
+		:	libraryPath(std::move(libraryPathIn)),
+			resolvedPath(std::move(resolvedPathIn)),
+			dlopenHandle(std::move(dlopenHandleIn))
+		{}
+
+		std::string libraryPath;
+		std::string resolvedPath;
+		std::unique_ptr<void, SharedLibraryDeleter> dlopenHandle;
+		std::atomic<bool> isBeingDestroyed{false};
+
+		void* getDlopenHandle() const
+		{
+			return dlopenHandle.get();
+		}
+	};
+
+	struct Resources
+	{
+		std::vector<std::shared_ptr<LoadedSharedLibrary>> loadedSharedLibraries;
+	};
+
+	static LoadableLibraryManager& getInstance()
+	{
+		static LoadableLibraryManager instance;
+		return instance;
+	}
+
+	std::optional<std::string> searchForLibInSmoSearchPaths(
+		const std::string& libraryPath) const;
+
+	std::shared_ptr<LoadedSharedLibrary> loadSharedLibrary(
+		const std::string& libraryPath);
+
+	void unloadSharedLibrary(
+		const std::shared_ptr<LoadedSharedLibrary>& loadedLibrary);
+
+	template<typename FnPtr>
+	static FnPtr resolveSymbol(void* handle, const char* symbolName)
+	{
+		dlerror();
+		auto symbol = reinterpret_cast<FnPtr>(dlsym(handle, symbolName));
+		const char* dlerr = dlerror();
+		if (dlerr != nullptr)
+		{
+			throw std::runtime_error(
+				std::string("dlsym('") + symbolName + "') failed: " + dlerr);
+		}
+
+		if (symbol == nullptr)
+		{
+			throw std::runtime_error(
+				std::string("dlsym('") + symbolName + "') returned null");
+		}
+
+		return symbol;
+	}
+
+public:
+	sscl::SharedResourceGroup<sscl::co::CoQutex, Resources> s;
+
+private:
+	LoadableLibraryManager()
+	:	s("LoadableLibraryManager")
+	{}
+
+	~LoadableLibraryManager();
+
+	LoadableLibraryManager(const LoadableLibraryManager&) = delete;
+	LoadableLibraryManager& operator=(const LoadableLibraryManager&) = delete;
+
+	void appendLoadedSharedLibrary(
+		const std::shared_ptr<LoadedSharedLibrary>& loadedLibrary);
+
+	void removeLoadedSharedLibrary(
+		const std::shared_ptr<LoadedSharedLibrary>& loadedLibrary);
+};
+
+} // namespace loadable_lib
+} // namespace smo
+
+#endif // LOADABLE_LIBRARY_MANAGER_H

smocore/include/stimBuffApis/stimBuffApiLib.h

@@ -3,11 +3,10 @@
 
 #include <string>
 #include <memory>
-#include <atomic>
 #include <vector>
-#include <dlfcn.h>
 #include <functional>
 #include <user/senseApiDesc.h>
+#include <loadableLib/loadableLibraryManager.h>
 #include <spinscale/co/coQutex.h>
 #include <spinscale/sharedResourceGroup.h>
 
@@ -18,25 +17,15 @@ class StimBuffApiLib
 {
 private:
 	friend class StimBuffApiManager;
-	struct DlCloser
-	{
-		void operator()(void* handle) const
-		{
-			if (handle) {
-				dlclose(handle);
-			}
-		}
-	};
 
 public:
 	StimBuffApiLib(
-		const std::string& path, void *_dlopen_handle,
+		std::shared_ptr<loadable_lib::LoadableLibraryManager::LoadedSharedLibrary>
+			_loadedSharedLibrary,
 		SMO_GET_STIM_BUFF_API_DESC_FN_TYPEDEF *descFn)
-	: libraryPath(path),
-	isBeingDestroyed(false),
-	dlopen_handle(_dlopen_handle, DlCloser()),
-	SMO_GET_STIM_BUFF_API_DESC_FN_NAME(descFn),
-	s("StimBuffApiLib-" + path)
+	:	loadedSharedLibrary(std::move(_loadedSharedLibrary)),
+		SMO_GET_STIM_BUFF_API_DESC_FN_NAME(descFn),
+		s("StimBuffApiLib-" + loadedSharedLibrary->libraryPath)
 	{}
 
 	void setStimBuffApiDesc(const StimBuffApiDesc &desc)
@@ -45,19 +34,19 @@ public:
 		{
 			throw std::runtime_error(
 				std::string(__func__) + ": Sanity check failed for stim buff API "
-				"descriptor in library '" + libraryPath + "'");
+				"descriptor in library '"
+				+ loadedSharedLibrary->libraryPath + "'");
 		}
 
 		stimBuffApiDesc = desc;
 	}
 
 public:
-	std::string libraryPath;
-	std::atomic<bool> isBeingDestroyed;
-	std::unique_ptr<void, DlCloser> dlopen_handle;
-	/* UNIMPLEMENTED: API-specific cmdline options. These affect this specific
-	 * stim buff api lib's behaviour globally.
-	 */
+	std::shared_ptr<loadable_lib::LoadableLibraryManager::LoadedSharedLibrary>
+		loadedSharedLibrary;
+    /* UNIMPLEMENTED: API-specific cmdline options. These affect this specific
+     * stim buff api lib's behaviour globally.
+     */
 	std::vector<std::string> options;
 
 	/**
@@ -80,11 +69,13 @@ public:
 
 	struct StimBuffApiLibResources
 	{};
-	
+
 	sscl::SharedResourceGroup<sscl::co::CoQutex, StimBuffApiLibResources> s;
 
-	std::string stringify() const {
-		std::string result = "Library Path: " + libraryPath + "\n";
+	std::string stringify() const
+	{
+		std::string result = "Library Path: "
+			+ loadedSharedLibrary->libraryPath + "\n";
 		result += "Stim Buff API Descriptor: " + stimBuffApiDesc.stringify() + "\n";
 		return result;
 	}

smocore/include/stimBuffApis/stimBuffApiManager.h

@@ -21,7 +21,7 @@ class StimBuffApiManager
 public:
 	struct Resources
 	{
-		std::vector<std::shared_ptr<StimBuffApiLib>> stimBuffApiLibs;
+		std::vector<std::shared_ptr<StimBuffApiLib>> libs;
 	};
 
 	static StimBuffApiManager& getInstance()
@@ -39,7 +39,7 @@ public:
 		const std::string& libraryPath,
 		const std::shared_ptr<sscl::ComponentThread>& componentThread);
 
-	std::optional<std::shared_ptr<StimBuffApiLib>> getStimBuffApiLib(
+	std::optional<std::shared_ptr<StimBuffApiLib>> findStimBuffApiLibByLibraryPath(
 		const std::string& libraryPath);
 	std::optional<std::shared_ptr<StimBuffApiLib>> findStimBuffApiLibByApiName(
 		const std::string& apiName);
@@ -48,19 +48,21 @@ public:
 
 	void loadAllStimBuffApiLibsFromOptions(
 		const std::shared_ptr<sscl::ComponentThread>& componentThread);
-
 	void unloadAllStimBuffApiLibs(void);
 
 	body::BodyViralPostingInvoker<void> initializeStimBuffApiLibCReq(
-		StimBuffApiLib &lib, bool acquireSbamLock=true);
+		StimBuffApiLib &lib, bool acquireListLock=true);
 	body::BodyViralPostingInvoker<void> finalizeStimBuffApiLibCReq(
-		StimBuffApiLib &lib, bool acquireSbamLock=true);
+		StimBuffApiLib &lib, bool acquireListLock=true);
 
 	body::BodyViralPostingInvoker<void> initializeAllStimBuffApiLibsCReq();
 	body::BodyViralPostingInvoker<void> finalizeAllStimBuffApiLibsCReq();
 
 	std::string stringifyLibs() const;
 
+public:
+	sscl::SharedResourceGroup<sscl::co::CoQutex, Resources> s;
+
 private:
 	StimBuffApiManager()
 	: s("StimBuffApiManager")
@@ -70,13 +72,6 @@ private:
 
 	StimBuffApiManager(const StimBuffApiManager&) = delete;
 	StimBuffApiManager& operator=(const StimBuffApiManager&) = delete;
-
-public:
-	sscl::SharedResourceGroup<sscl::co::CoQutex, Resources> s;
-
-public:
-	static std::optional<std::string> searchForLibInSmoSearchPaths(
-		const std::string& libraryPath);
 };
 
 } // namespace stim_buff