browser,file_manager: rework file manager handling

The previous design had a memory leak which couldn't be fixed,
amongst other issues.

src/browser.hxx

@@ -1,6 +1,8 @@
 #ifndef _BOLT_BROWSER_HXX_
 #define _BOLT_BROWSER_HXX_
 #include "browser/common.hxx"
+#include "file_manager.hxx"
+
 #include "include/cef_client.h"
 #include "include/internal/cef_ptr.h"
 #include "include/views/cef_window.h"
@@ -93,6 +95,7 @@ namespace Browser {
 			CefRefPtr<CefWindow> window;
 			CefRefPtr<CefBrowserView> browser_view;
 			CefRefPtr<CefBrowser> browser;
+			CefRefPtr<FileManager::FileManager> file_manager;
 			CefRefPtr<Window> pending_child;
 			std::vector<CefRefPtr<Window>> children;
 			CefPopupFeatures popup_features;

src/browser/client.cxx

@@ -29,6 +29,9 @@ constexpr Browser::Details LAUNCHER_DETAILS = {
 };
 
 Browser::Client::Client(CefRefPtr<Browser::App> app,std::filesystem::path config_dir, std::filesystem::path data_dir):
+#if defined(BOLT_DEV_LAUNCHER_DIRECTORY)
+	CLIENT_FILEHANDLER(BOLT_DEV_LAUNCHER_DIRECTORY),
+#endif
 	is_closing(false), show_devtools(SHOW_DEVTOOLS), config_dir(config_dir), data_dir(data_dir)
 {
 	app->SetBrowserProcessHandler(this);
@@ -42,7 +45,7 @@ void Browser::Client::OpenLauncher() {
 	std::lock_guard<std::mutex> _(this->windows_lock);
 	auto it = std::find_if(this->windows.begin(), this->windows.end(), [](CefRefPtr<Window>& win) { return win->IsLauncher(); });
 	if (it == this->windows.end()) {
-		CefRefPtr<Window> w = new Launcher(this, LAUNCHER_DETAILS, this->show_devtools, &this->file_manager, this->config_dir, this->data_dir);
+		CefRefPtr<Window> w = new Launcher(this, LAUNCHER_DETAILS, this->show_devtools, this, this->config_dir, this->data_dir);
 		this->windows.push_back(w);
 	} else {
 		(*it)->Focus();
@@ -97,7 +100,7 @@ void Browser::Client::OnContextInitialized() {
 	// After main() enters its event loop, this function will be called on the main thread when CEF
 	// context is ready to go, so, as suggested by CEF examples, Bolt treats this as an entry point.
 	std::lock_guard<std::mutex> _(this->windows_lock);
-	CefRefPtr<Browser::Window> w = new Launcher(this, LAUNCHER_DETAILS, this->show_devtools, &this->file_manager, this->config_dir, this->data_dir);
+	CefRefPtr<Browser::Window> w = new Launcher(this, LAUNCHER_DETAILS, this->show_devtools, this, this->config_dir, this->data_dir);
 	this->windows.push_back(w);
 }
 

src/browser/client.hxx

@@ -18,8 +18,10 @@
 
 #if defined(BOLT_DEV_LAUNCHER_DIRECTORY)
 #include "../file_manager/directory.hxx"
+typedef FileManager::Directory CLIENT_FILEHANDLER;
 #else
 #include "../file_manager/launcher.hxx"
+typedef FileManager::Launcher CLIENT_FILEHANDLER;
 #endif
 
 namespace Browser {
@@ -28,7 +30,7 @@ namespace Browser {
 	/// https://github.com/chromiumembedded/cef/blob/5735/include/cef_browser_process_handler.h
 	/// https://github.com/chromiumembedded/cef/blob/5735/include/cef_life_span_handler.h
 	/// https://github.com/chromiumembedded/cef/blob/5735/include/cef_request_handler.h
-	struct Client: public CefClient, CefBrowserProcessHandler, CefLifeSpanHandler, CefRequestHandler {
+	struct Client: public CefClient, CefBrowserProcessHandler, CefLifeSpanHandler, CefRequestHandler, CLIENT_FILEHANDLER {
 		Client(CefRefPtr<Browser::App>, std::filesystem::path config_dir, std::filesystem::path data_dir);
 
 		/// Either opens a launcher window, or focuses an existing one. No more than one launcher window
@@ -98,12 +100,6 @@ namespace Browser {
 			std::filesystem::path config_dir;
 			std::filesystem::path data_dir;
 
-#if defined(BOLT_DEV_LAUNCHER_DIRECTORY)
-			FileManager::Directory file_manager = FileManager::Directory(BOLT_DEV_LAUNCHER_DIRECTORY);
-#else
-			FileManager::Launcher file_manager;
-#endif
-
 #if defined(CEF_X11)
 			xcb_connection_t* xcb;
 #endif

src/browser/resource_handler.cxx

@@ -31,6 +31,7 @@ bool Browser::ResourceHandler::Read(void* data_out, int bytes_to_read, int& byte
 		memcpy(data_out, this->data + this->cursor, bytes_read);
 		this->cursor = this->data_len;
 	}
+	if (this->cursor == this->data_len) this->finish();
 	return true;
 }
 
@@ -49,8 +50,16 @@ bool Browser::ResourceHandler::Skip(int64 bytes_to_skip, int64& bytes_skipped, C
 
 void Browser::ResourceHandler::Cancel() {
 	this->cursor = this->data_len;
+	this->finish();
 }
 
 CefRefPtr<CefResourceHandler> Browser::ResourceHandler::GetResourceHandler(CefRefPtr<CefBrowser>, CefRefPtr<CefFrame>, CefRefPtr<CefRequest>) {
 	return this;
 }
+
+void Browser::ResourceHandler::finish() {
+	if (this->file_manager) {
+		this->file_manager->free(FileManager::File { .contents = this->data, .size = this->data_len, .mime_type = this->mime });
+		this->file_manager = nullptr;
+	}
+}

src/browser/resource_handler.hxx

@@ -1,6 +1,8 @@
 #ifndef _BOLT_RESOURCE_HANDLER_HXX_
 #define _BOLT_RESOURCE_HANDLER_HXX_
 
+#include "../file_manager.hxx"
+
 #include "include/cef_base.h"
 #include "include/cef_request_handler.h"
 
@@ -10,9 +12,13 @@ namespace Browser {
 	/// https://github.com/chromiumembedded/cef/blob/5735/include/cef_resource_handler.h
 	struct ResourceHandler: public CefResourceRequestHandler, CefResourceHandler {
 		ResourceHandler(const unsigned char* data, size_t len, int status, CefString mime):
-			data(data), data_len(len), status(status), mime(mime), has_location(false), cursor(0) { }
+			data(data), data_len(len), status(status), mime(mime), has_location(false), cursor(0), file_manager(nullptr) { }
 		ResourceHandler(const unsigned char* data, size_t len, int status, CefString mime, CefString location):
-			data(data), data_len(len), status(status), mime(mime), location(location), has_location(true), cursor(0) { }
+			data(data), data_len(len), status(status), mime(mime), location(location), has_location(true), cursor(0), file_manager(nullptr) { }
+		
+		/// This constructor assumes the file does exist i.e. all params are initialised, and status will be 200
+		ResourceHandler(FileManager::File file, CefRefPtr<FileManager::FileManager> file_manager):
+			ResourceHandler(file.contents, file.size, 200, file.mime_type) { this->file_manager = file_manager; }
 
 		bool Open(CefRefPtr<CefRequest>, bool&, CefRefPtr<CefCallback>) override;
 		void GetResponseHeaders(CefRefPtr<CefResponse>, int64&, CefString&) override;
@@ -24,6 +30,8 @@ namespace Browser {
 		protected:
 			ResourceHandler(CefString mime): cursor(0), has_location(false), mime(mime) { }
 
+			void finish();
+
 			const unsigned char* data;
 			size_t data_len;
 			int status;
@@ -31,6 +39,7 @@ namespace Browser {
 			CefString location;
 			bool has_location;
 			size_t cursor;
+			CefRefPtr<FileManager::FileManager> file_manager;
 			IMPLEMENT_REFCOUNTING(ResourceHandler);
 			DISALLOW_COPY_AND_ASSIGN(ResourceHandler);
 	};

src/browser/window_launcher.cxx

@@ -76,7 +76,7 @@ Browser::Launcher::Launcher(
 	CefRefPtr<Browser::Client> client,
 	Details details,
 	bool show_devtools,
-	const FileManager::FileManager* const file_manager,
+	CefRefPtr<FileManager::FileManager> file_manager,
 	std::filesystem::path config_dir,
 	std::filesystem::path data_dir
 ): Window(client, details, show_devtools), data_dir(data_dir), file_manager(file_manager) {
@@ -293,8 +293,9 @@ CefRefPtr<CefResourceRequestHandler> Browser::Launcher::GetResourceRequestHandle
 		// respond using internal hashmap of filenames
 		FileManager::File file = this->file_manager->get(path);
 		if (file.contents) {
-			return new ResourceHandler(file.contents, file.size, 200, file.mime_type);
+			return new ResourceHandler(file, this->file_manager);
 		} else {
+			this->file_manager->free(file);
 			const char* data = "Not Found\n";
 			return new ResourceHandler(reinterpret_cast<const unsigned char*>(data), strlen(data), 404, "text/plain");
 		}
@@ -303,6 +304,11 @@ CefRefPtr<CefResourceRequestHandler> Browser::Launcher::GetResourceRequestHandle
 	return nullptr;
 }
 
+void Browser::Launcher::OnBrowserDestroyed(CefRefPtr<CefBrowserView> view, CefRefPtr<CefBrowser> browser) {
+	Window::OnBrowserDestroyed(view, browser);
+	this->file_manager = nullptr;
+}
+
 CefRefPtr<CefResourceRequestHandler> SaveFileFromPost(CefRefPtr<CefRequest> request, const std::filesystem::path::value_type* path) {
 	CefRefPtr<CefPostData> post_data = request->GetPostData();
 	if (post_data->GetElementCount() != 1) {

src/browser/window_launcher.hxx

@@ -10,7 +10,7 @@
 
 namespace Browser {
 	struct Launcher: public Window {
-		Launcher(CefRefPtr<Browser::Client>, Details, bool, const FileManager::FileManager* const, std::filesystem::path, std::filesystem::path);
+		Launcher(CefRefPtr<Browser::Client>, Details, bool, CefRefPtr<FileManager::FileManager>, std::filesystem::path, std::filesystem::path);
 
 		bool IsLauncher() const override;
 
@@ -24,6 +24,8 @@ namespace Browser {
 			bool&
 		) override;
 
+		void OnBrowserDestroyed(CefRefPtr<CefBrowserView>, CefRefPtr<CefBrowser>) override;
+
 		/// Attempts to open the given URL externally in the user's browser
 		void OpenExternalUrl(char* url) const;
 
@@ -37,7 +39,7 @@ namespace Browser {
 
 		private:
 			const std::string internal_url = "https://bolt-internal/";
-			const FileManager::FileManager* file_manager;
+			CefRefPtr<FileManager::FileManager> file_manager;
 			std::filesystem::path data_dir;
 			std::filesystem::path creds_path;
 			std::filesystem::path config_path;

src/file_manager.hxx

@@ -1,5 +1,6 @@
 #ifndef _BOLT_FILE_MANAGER_HXX_
 #define _BOLT_FILE_MANAGER_HXX_
+#include "include/cef_base.h"
 #include "include/internal/cef_string.h"
 
 #include <string_view>
@@ -16,7 +17,7 @@ namespace FileManager {
 		CefString mime_type;
 	};
 
-	class FileManager {
+	class FileManager: public CefBaseRefCounted {
 		public:
 			/// Fetches a file, as if from a web server, by its abolsute path.
 			/// For example, in the url "https://adamcake.com/index.html", the path would be "/index.html".