Merge branch 'master' into doc-refactor-2

builtin/common/misc_helpers.lua

@@ -490,6 +490,9 @@ end
 
 
 function table.insert_all(t, other)
+	if table.move then -- LuaJIT
+		return table.move(other, 1, #other, #t + 1, t)
+	end
 	for i=1, #other do
 		t[#t + 1] = other[i]
 	end

builtin/game/features.lua

@@ -39,6 +39,7 @@ core.features = {
 	dynamic_add_media_filepath = true,
 	lsystem_decoration_type = true,
 	item_meta_range = true,
+	node_interaction_actor = true,
 }
 
 function core.has_feature(arg)

builtin/init.lua

@@ -26,7 +26,15 @@ do
 		core.print = nil -- don't pollute our namespace
 	end
 end
-math.randomseed(os.time())
+
+do
+	-- Note that PUC Lua just calls srand() which is already initialized by C++,
+	-- but we don't want to rely on this implementation detail.
+	local seed = 1048576 * (os.time() % 1048576)
+	seed = seed + core.get_us_time() % 1048576
+	math.randomseed(seed)
+end
+
 minetest = core
 
 -- Load other files

builtin/mainmenu/content/dlg_contentstore.lua

@@ -98,15 +98,12 @@ local function download_and_extract(param)
 
 	local tempfolder = core.get_temp_path()
 	if tempfolder ~= "" then
-		tempfolder = tempfolder .. DIR_DELIM .. "MT_" .. math.random(1, 1024000)
 		if not core.extract_zip(filename, tempfolder) then
 			tempfolder = nil
 		end
-	else
-		tempfolder = nil
 	end
 	os.remove(filename)
-	if not tempfolder then
+	if not tempfolder or tempfolder == "" then
 		return {
 			msg = fgettext_ne("Failed to extract \"$1\" (unsupported file type or broken archive)", package.title),
 		}

builtin/mainmenu/serverlistmgr.lua

@@ -80,7 +80,8 @@ local WEIGHT_SORT = 2
 -- how much the estimated latency contributes to the final ranking
 local WEIGHT_LATENCY = 1
 
-local function order_server_list(list)
+--- @param list of servers, will be modified.
+local function order_server_list_internal(list)
 	-- calculate the scores
 	local s1 = Normalizer:new()
 	local s2 = Normalizer:new()
@@ -99,22 +100,36 @@ local function order_server_list(list)
 	s1 = s1:calc()
 	s2 = s2:calc()
 
-	-- make a shallow copy and pre-calculate ordering
-	local res, order = {}, {}
-	for i = 1, #list do
-		local fav = list[i]
-		res[i] = fav
-
-		local n = s1[fav] * WEIGHT_SORT + s2[fav] * WEIGHT_LATENCY
-		order[fav] = n
+	-- pre-calculate ordering
+	local order = {}
+	for _, fav in ipairs(list) do
+		order[fav] = s1[fav] * WEIGHT_SORT + s2[fav] * WEIGHT_LATENCY
 	end
 
 	-- now sort the list
-	table.sort(res, function(fav1, fav2)
+	table.sort(list, function(fav1, fav2)
 		return order[fav1] > order[fav2]
 	end)
+end
 
-	return res
+local function order_server_list(list)
+	-- split the list into two parts and sort them separately, to keep empty
+	-- servers at the bottom.
+	local nonempty, empty = {}, {}
+
+	for _, fav in ipairs(list) do
+		if (fav.clients or 0) > 0 then
+			table.insert(nonempty, fav)
+		else
+			table.insert(empty, fav)
+		end
+	end
+
+	order_server_list_internal(nonempty)
+	order_server_list_internal(empty)
+
+	table.insert_all(nonempty, empty)
+	return nonempty
 end
 
 local public_downloading = false

client/shaders/cloud_shader/opengl_fragment.glsl

@@ -1,7 +1,7 @@
-uniform vec4 fogColor;
+uniform lowp vec4 fogColor;
 uniform float fogDistance;
 uniform float fogShadingParameter;
-varying vec3 eyeVec;
+varying highp vec3 eyeVec;
 
 varying lowp vec4 varColor;
 

client/shaders/cloud_shader/opengl_vertex.glsl

@@ -1,8 +1,8 @@
-uniform vec4 emissiveColor;
+uniform lowp vec4 emissiveColor;
 
 varying lowp vec4 varColor;
 
-varying vec3 eyeVec;
+varying highp vec3 eyeVec;
 
 void main(void)
 {

client/shaders/nodes_shader/opengl_fragment.glsl

@@ -1,13 +1,12 @@
 uniform sampler2D baseTexture;
 
 uniform vec3 dayLight;
-uniform vec4 fogColor;
+uniform lowp vec4 fogColor;
 uniform float fogDistance;
 uniform float fogShadingParameter;
-uniform vec3 eyePosition;
 
 // The cameraOffset is the current center of the visible world.
-uniform vec3 cameraOffset;
+uniform highp vec3 cameraOffset;
 uniform float animationTimer;
 #ifdef ENABLE_DYNAMIC_SHADOWS
 	// shadow texture
@@ -44,11 +43,8 @@ varying mediump vec2 varTexCoord;
 #else
 centroid varying vec2 varTexCoord;
 #endif
-varying vec3 eyeVec;
+varying highp vec3 eyeVec;
 varying float nightRatio;
-varying vec3 tsEyeVec;
-varying vec3 lightVec;
-varying vec3 tsLightVec;
 
 #ifdef ENABLE_DYNAMIC_SHADOWS
 

client/shaders/nodes_shader/opengl_vertex.glsl

@@ -1,10 +1,9 @@
 uniform mat4 mWorld;
 // Color of the light emitted by the sun.
 uniform vec3 dayLight;
-uniform vec3 eyePosition;
 
 // The cameraOffset is the current center of the visible world.
-uniform vec3 cameraOffset;
+uniform highp vec3 cameraOffset;
 uniform float animationTimer;
 
 varying vec3 vNormal;
@@ -44,7 +43,7 @@ centroid varying vec2 varTexCoord;
 
 varying float area_enable_parallax;
 
-varying vec3 eyeVec;
+varying highp vec3 eyeVec;
 varying float nightRatio;
 // Color of the light emitted by the light sources.
 const vec3 artificialLight = vec3(1.04, 1.04, 1.04);

client/shaders/object_shader/opengl_fragment.glsl

@@ -1,13 +1,12 @@
 uniform sampler2D baseTexture;
 
 uniform vec3 dayLight;
-uniform vec4 fogColor;
+uniform lowp vec4 fogColor;
 uniform float fogDistance;
 uniform float fogShadingParameter;
-uniform vec3 eyePosition;
 
 // The cameraOffset is the current center of the visible world.
-uniform vec3 cameraOffset;
+uniform highp vec3 cameraOffset;
 uniform float animationTimer;
 #ifdef ENABLE_DYNAMIC_SHADOWS
 	// shadow texture
@@ -44,7 +43,7 @@ varying mediump vec2 varTexCoord;
 #else
 centroid varying vec2 varTexCoord;
 #endif
-varying vec3 eyeVec;
+varying highp vec3 eyeVec;
 varying float nightRatio;
 
 varying float vIDiff;

client/shaders/object_shader/opengl_vertex.glsl

@@ -1,10 +1,7 @@
 uniform mat4 mWorld;
 uniform vec3 dayLight;
-uniform vec3 eyePosition;
 uniform float animationTimer;
-uniform vec4 emissiveColor;
-uniform vec3 cameraOffset;
-
+uniform lowp vec4 emissiveColor;
 
 varying vec3 vNormal;
 varying vec3 vPosition;
@@ -33,7 +30,7 @@ centroid varying vec2 varTexCoord;
 	varying float perspective_factor;
 #endif
 
-varying vec3 eyeVec;
+varying highp vec3 eyeVec;
 varying float nightRatio;
 // Color of the light emitted by the light sources.
 const vec3 artificialLight = vec3(1.04, 1.04, 1.04);

client/shaders/stars_shader/opengl_fragment.glsl

@@ -1,4 +1,4 @@
-uniform vec4 emissiveColor;
+uniform lowp vec4 emissiveColor;
 
 void main(void)
 {

doc/lua_api.md

@@ -5348,6 +5348,9 @@ Minetest includes the following settings to control behavior of privileges:
       lsystem_decoration_type = true,
       -- Overrideable pointing range using the itemstack meta key `"range"` (5.9.0)
       item_meta_range = true,
+      -- Allow passing an optional "actor" ObjectRef to the following functions:
+      -- minetest.place_node, minetest.dig_node, minetest.punch_node (5.9.0)
+      node_interaction_actor = true,
   }
   ```
 
@@ -5977,13 +5980,16 @@ handler.
     * Returns a number between `0` and `15`
     * Currently it's the same as `math.floor(param1 / 16)`, except that it
       ensures compatibility.
-* `minetest.place_node(pos, node)`
+* `minetest.place_node(pos, node[, placer])`
     * Place node with the same effects that a player would cause
-* `minetest.dig_node(pos)`
+    * `placer`: The ObjectRef that places the node (optional)
+* `minetest.dig_node(pos[, digger])`
     * Dig node with the same effects that a player would cause
+    * `digger`: The ObjectRef that digs the node (optional)
     * Returns `true` if successful, `false` on failure (e.g. protected location)
-* `minetest.punch_node(pos)`
+* `minetest.punch_node(pos[, puncher])`
     * Punch node with the same effects that a player would cause
+    * `puncher`: The ObjectRef that punches the node (optional)
 * `minetest.spawn_falling_node(pos)`
     * Change node into falling node
     * Returns `true` and the ObjectRef of the spawned entity if successful, `false` on failure

doc/menu_lua_api.md

@@ -90,8 +90,8 @@ The "gamedata" table is read when calling `core.start()`. It should contain:
     registered in the core (possible in async calls)
 * `core.get_cache_path()` -> path of cache
 * `core.get_temp_path([param])` (possible in async calls)
-    * `param`=true: returns path to a temporary file
-    otherwise: returns path to the temporary folder
+  * `param == true`: returns path to a newly created temporary file
+  * otherwise: returns path to a newly created temporary folder
 
 
 

src/CMakeLists.txt

@@ -698,11 +698,13 @@ include(CheckCSourceCompiles)
 
 set(CMAKE_REQUIRED_INCLUDES ${LUA_INCLUDE_DIR})
 if(USE_LUAJIT)
-	set(CMAKE_REQUIRED_LIBRARIES ${LUA_LIBRARY})
+	# libm usually required if statically linking
+	set(CMAKE_REQUIRED_LIBRARIES ${LUA_LIBRARY} m)
 	# LuaJIT provides exactly zero ways to determine how recent it is (the version
 	# is unchanged since 2017), however it happens that string buffers were added
 	# after the changes which we care about so that works as an indicator.
 	# (https://github.com/LuaJIT/LuaJIT/commit/4c6b669 March 2021)
+	# Note: This is no longer true as of August 2023, but we're keeping the old check.
 	unset(HAVE_RECENT_LJ CACHE)
 	check_symbol_exists(luaopen_string_buffer "lualib.h" HAVE_RECENT_LJ)
 	if(NOT HAVE_RECENT_LJ)

src/client/client.cpp

@@ -1795,6 +1795,11 @@ float Client::mediaReceiveProgress()
 	return 1.0; // downloader only exists when not yet done
 }
 
+void Client::drawLoadScreen(const std::wstring &text, float dtime, int percent) {
+	m_rendering_engine->run();
+	m_rendering_engine->draw_load_screen(text, guienv, m_tsrc, dtime, percent);
+}
+
 struct TextureUpdateArgs {
 	gui::IGUIEnvironment *guienv;
 	u64 last_time_ms;

src/client/client.h

@@ -356,6 +356,7 @@ public:
 
 	float mediaReceiveProgress();
 
+	void drawLoadScreen(const std::wstring &text, float dtime, int percent);
 	void afterContentReceived();
 	void showUpdateProgressTexture(void *args, u32 progress, u32 max_progress);
 

src/client/clientmedia.cpp

@@ -18,6 +18,7 @@ with this program; if not, write to the Free Software Foundation, Inc.,
 */
 
 #include "clientmedia.h"
+#include "gettext.h"
 #include "httpfetch.h"
 #include "client.h"
 #include "filecache.h"
@@ -184,6 +185,11 @@ void ClientMediaDownloader::step(Client *client)
 
 void ClientMediaDownloader::initialStep(Client *client)
 {
+	std::wstring loading_text = wstrgettext("Media...");
+	// Tradeoff between responsiveness during media loading and media loading speed
+	const u64 chunk_time_ms = 33;
+	u64 last_time = porting::getTimeMs();
+
 	// Check media cache
 	m_uncached_count = m_files.size();
 	for (auto &file_it : m_files) {
@@ -195,6 +201,13 @@ void ClientMediaDownloader::initialStep(Client *client)
 			filestatus->received = true;
 			m_uncached_count--;
 		}
+
+		u64 cur_time = porting::getTimeMs();
+		u64 dtime = porting::getDeltaMs(last_time, cur_time);
+		if (dtime >= chunk_time_ms) {
+			client->drawLoadScreen(loading_text, dtime / 1000.0f, 30);
+			last_time = cur_time;
+		}
 	}
 
 	assert(m_uncached_received_count == 0);

src/client/game.cpp

@@ -66,6 +66,7 @@ with this program; if not, write to the Free Software Foundation, Inc.,
 #include "settings.h"
 #include "shader.h"
 #include "sky.h"
+#include "threading/lambda.h"
 #include "translation.h"
 #include "util/basic_macros.h"
 #include "util/directiontables.h"
@@ -381,11 +382,9 @@ class GameGlobalShaderConstantSetter : public IShaderConstantSetter
 	CachedPixelShaderSetting<float>
 		m_animation_timer_delta_pixel{"animationTimerDelta"};
 	CachedPixelShaderSetting<float, 3> m_day_light{"dayLight"};
-	CachedPixelShaderSetting<float, 3> m_eye_position_pixel{"eyePosition"};
-	CachedVertexShaderSetting<float, 3> m_eye_position_vertex{"eyePosition"};
 	CachedPixelShaderSetting<float, 3> m_minimap_yaw{"yawVec"};
 	CachedPixelShaderSetting<float, 3> m_camera_offset_pixel{"cameraOffset"};
-	CachedPixelShaderSetting<float, 3> m_camera_offset_vertex{"cameraOffset"};
+	CachedVertexShaderSetting<float, 3> m_camera_offset_vertex{"cameraOffset"};
 	CachedPixelShaderSetting<SamplerLayer_t> m_texture0{"texture0"};
 	CachedPixelShaderSetting<SamplerLayer_t> m_texture1{"texture1"};
 	CachedPixelShaderSetting<SamplerLayer_t> m_texture2{"texture2"};
@@ -483,10 +482,6 @@ public:
 		m_animation_timer_delta_vertex.set(&animation_timer_delta_f, services);
 		m_animation_timer_delta_pixel.set(&animation_timer_delta_f, services);
 
-		v3f epos = m_client->getEnv().getLocalPlayer()->getEyePosition();
-		m_eye_position_pixel.set(epos, services);
-		m_eye_position_vertex.set(epos, services);
-
 		if (m_client->getMinimap()) {
 			v3f minimap_yaw = m_client->getMinimap()->getYawVec();
 			m_minimap_yaw.set(minimap_yaw, services);
@@ -1020,12 +1015,6 @@ Game::Game() :
 
 Game::~Game()
 {
-	delete client;
-	delete soundmaker;
-	sound_manager.reset();
-
-	delete server; // deleted first to stop all server threads
-
 	delete hud;
 	delete camera;
 	delete quicktune;
@@ -1274,6 +1263,28 @@ void Game::shutdown()
 			sleep_ms(100);
 		}
 	}
+
+	delete client;
+	delete soundmaker;
+	sound_manager.reset();
+
+	auto stop_thread = runInThread([=] {
+		delete server;
+	}, "ServerStop");
+
+	FpsControl fps_control;
+	fps_control.reset();
+
+	while (stop_thread->isRunning()) {
+		m_rendering_engine->run();
+		f32 dtime;
+		fps_control.limit(device, &dtime);
+		showOverlayMessage(N_("Shutting down..."), dtime, 0, false);
+	}
+
+	stop_thread->rethrow();
+
+	// to be continued in Game::~Game
 }
 
 
@@ -1379,11 +1390,33 @@ bool Game::createSingleplayerServer(const std::string &map_dir,
 
 	server = new Server(map_dir, gamespec, simple_singleplayer_mode, bind_addr,
 			false, nullptr, error_message);
-	server->start();
 
-	copyServerClientCache();
+	auto start_thread = runInThread([=] {
+		server->start();
+		copyServerClientCache();
+	}, "ServerStart");
 
-	return true;
+	input->clear();
+	bool success = true;
+
+	FpsControl fps_control;
+	fps_control.reset();
+
+	while (start_thread->isRunning()) {
+		if (!m_rendering_engine->run() || input->cancelPressed())
+			success = false;
+		f32 dtime;
+		fps_control.limit(device, &dtime);
+
+		if (success)
+			showOverlayMessage(N_("Creating server..."), dtime, 5);
+		else
+			showOverlayMessage(N_("Shutting down..."), dtime, 0, false);
+	}
+
+	start_thread->rethrow();
+
+	return success;
 }
 
 void Game::copyServerClientCache()

src/client/hud.cpp

@@ -801,7 +801,7 @@ void Hud::drawCrosshair()
 		core::dimension2di orig_size(tex->getOriginalSize());
 		// Integer scaling to avoid artifacts, floor instead of round since too
 		// small looks better than too large in this case.
-		core::dimension2di scaled_size = orig_size * std::floor(m_scale_factor);
+		core::dimension2di scaled_size = orig_size * std::max(std::floor(m_scale_factor), 1.0f);
 
 		core::rect<s32> src_rect(orig_size);
 		core::position2d pos(m_displaycenter.X - scaled_size.Width / 2,

src/debug.h

@@ -19,7 +19,6 @@ with this program; if not, write to the Free Software Foundation, Inc.,
 
 #pragma once
 
-#include <iostream>
 #include <exception>
 #include <cassert>
 #include "gettime.h"

src/filesys.cpp

@@ -223,6 +223,16 @@ std::string CreateTempFile()
 	return path;
 }
 
+std::string CreateTempDir()
+{
+	std::string path = TempPath() + DIR_DELIM "MT_XXXXXX";
+	_mktemp_s(&path[0], path.size() + 1); // modifies path
+	// will error if it already exists
+	if (!CreateDirectory(path.c_str(), nullptr))
+		return "";
+	return path;
+}
+
 bool CopyFileContents(const std::string &source, const std::string &target)
 {
 	BOOL ok = CopyFileEx(source.c_str(), target.c_str(), nullptr, nullptr,
@@ -446,6 +456,15 @@ std::string CreateTempFile()
 	return path;
 }
 
+std::string CreateTempDir()
+{
+	std::string path = TempPath() + DIR_DELIM "MT_XXXXXX";
+	auto r = mkdtemp(&path[0]); // modifies path
+	if (!r)
+		return "";
+	return path;
+}
+
 namespace {
 	struct FileDeleter {
 		void operator()(FILE *stream) {

src/filesys.h

@@ -75,13 +75,19 @@ bool RecursiveDelete(const std::string &path);
 
 bool DeleteSingleFileOrEmptyDirectory(const std::string &path);
 
-// Returns path to temp directory, can return "" on error
+/// Returns path to temp directory.
+/// You probably don't want to use this directly, see `CreateTempFile` or `CreateTempDir`.
+/// @return path or "" on error
 std::string TempPath();
 
-// Returns path to securely-created temporary file (will already exist when this function returns)
-// can return "" on error
+/// Returns path to securely-created temporary file (will already exist when this function returns).
+/// @return path or "" on error
 std::string CreateTempFile();
 
+/// Returns path to securely-created temporary directory (will already exist when this function returns).
+/// @return path or "" on error
+std::string CreateTempDir();
+
 /* Returns a list of subdirectories, including the path itself, but excluding
        hidden directories (whose names start with . or _)
 */

src/script/lua_api/l_env.cpp

@@ -24,6 +24,7 @@ with this program; if not, write to the Free Software Foundation, Inc.,
 #include "lua_api/l_nodetimer.h"
 #include "lua_api/l_noise.h"
 #include "lua_api/l_vmanip.h"
+#include "lua_api/l_object.h"
 #include "common/c_converter.h"
 #include "common/c_content.h"
 #include "scripting_server.h"
@@ -416,7 +417,7 @@ int ModApiEnv::l_get_natural_light(lua_State *L)
 	return 1;
 }
 
-// place_node(pos, node)
+// place_node(pos, node, [placer])
 // pos = {x=num, y=num, z=num}
 int ModApiEnv::l_place_node(lua_State *L)
 {
@@ -436,6 +437,7 @@ int ModApiEnv::l_place_node(lua_State *L)
 		lua_pushboolean(L, false);
 		return 1;
 	}
+
 	// Create item to place
 	std::optional<ItemStack> item = ItemStack(ndef->get(n).name, 1, 0, idef);
 	// Make pointed position
@@ -443,13 +445,22 @@ int ModApiEnv::l_place_node(lua_State *L)
 	pointed.type = POINTEDTHING_NODE;
 	pointed.node_abovesurface = pos;
 	pointed.node_undersurface = pos + v3s16(0,-1,0);
-	// Place it with a NULL placer (appears in Lua as nil)
-	bool success = scriptIfaceItem->item_OnPlace(item, nullptr, pointed);
+
+	ServerActiveObject *placer = nullptr;
+
+	if (!lua_isnoneornil(L, 3)) {
+		ObjectRef *ref = checkObject<ObjectRef>(L, 3);
+		placer = ObjectRef::getobject(ref);
+	}
+
+	// Place it with a nullptr placer (appears in Lua as nil)
+	// or the given ObjectRef
+	bool success = scriptIfaceItem->item_OnPlace(item, placer, pointed);
 	lua_pushboolean(L, success);
 	return 1;
 }
 
-// dig_node(pos)
+// dig_node(pos, [digger])
 // pos = {x=num, y=num, z=num}
 int ModApiEnv::l_dig_node(lua_State *L)
 {
@@ -465,14 +476,23 @@ int ModApiEnv::l_dig_node(lua_State *L)
 		lua_pushboolean(L, false);
 		return 1;
 	}
-	// Dig it out with a NULL digger (appears in Lua as a
-	// non-functional ObjectRef)
-	bool success = scriptIfaceNode->node_on_dig(pos, n, NULL);
+
+	ServerActiveObject *digger = nullptr;
+
+	if (!lua_isnoneornil(L, 2)) {
+		ObjectRef *ref = checkObject<ObjectRef>(L, 2);
+		digger = ObjectRef::getobject(ref);
+	}
+
+	// Dig it out with a nullptr digger
+	// (appears in Lua as a non-functional ObjectRef)
+	// or the given ObjectRef
+	bool success = scriptIfaceNode->node_on_dig(pos, n, digger);
 	lua_pushboolean(L, success);
 	return 1;
 }
 
-// punch_node(pos)
+// punch_node(pos, [puncher])
 // pos = {x=num, y=num, z=num}
 int ModApiEnv::l_punch_node(lua_State *L)
 {
@@ -488,9 +508,19 @@ int ModApiEnv::l_punch_node(lua_State *L)
 		lua_pushboolean(L, false);
 		return 1;
 	}
-	// Punch it with a NULL puncher (appears in Lua as a non-functional
-	// ObjectRef)
-	bool success = scriptIfaceNode->node_on_punch(pos, n, NULL, PointedThing());
+
+	ServerActiveObject *puncher = nullptr;
+
+	if (!lua_isnoneornil(L, 2)) {
+		ObjectRef *ref = checkObject<ObjectRef>(L, 2);
+		puncher = ObjectRef::getobject(ref);
+	}
+
+	// Punch it with a nullptr puncher
+	// (appears in Lua as a non-functional ObjectRef)
+	// or the given ObjectRef
+	// TODO: custom PointedThing (requires a converter function)
+	bool success = scriptIfaceNode->node_on_punch(pos, n, puncher, PointedThing());
 	lua_pushboolean(L, success);
 	return 1;
 }

src/script/lua_api/l_env.h

@@ -89,15 +89,15 @@ private:
 	// timeofday: nil = current time, 0 = night, 0.5 = day
 	static int l_get_natural_light(lua_State *L);
 
-	// place_node(pos, node)
+	// place_node(pos, node, [placer])
 	// pos = {x=num, y=num, z=num}
 	static int l_place_node(lua_State *L);
 
-	// dig_node(pos)
+	// dig_node(pos, [digger])
 	// pos = {x=num, y=num, z=num}
 	static int l_dig_node(lua_State *L);
 
-	// punch_node(pos)
+	// punch_node(pos, [puncher])
 	// pos = {x=num, y=num, z=num}
 	static int l_punch_node(lua_State *L);
 

src/script/lua_api/l_mainmenu.cpp

@@ -729,7 +729,7 @@ int ModApiMainMenu::l_get_cache_path(lua_State *L)
 int ModApiMainMenu::l_get_temp_path(lua_State *L)
 {
 	if (lua_isnoneornil(L, 1) || !lua_toboolean(L, 1))
-		lua_pushstring(L, fs::TempPath().c_str());
+		lua_pushstring(L, fs::CreateTempDir().c_str());
 	else
 		lua_pushstring(L, fs::CreateTempFile().c_str());
 	return 1;

src/threading/lambda.h

@@ -0,0 +1,64 @@
+// Minetest
+// SPDX-License-Identifier: LGPL-2.1-or-later
+
+#pragma once
+
+#include <exception>
+#include <functional>
+#include <memory>
+#include "debug.h"
+#include "threading/thread.h"
+
+/**
+ * Class returned by `runInThread`.
+ *
+ * Provides the usual thread methods along with `rethrow()`.
+*/
+class LambdaThread : public Thread
+{
+	friend std::unique_ptr<LambdaThread> runInThread(
+		const std::function<void()> &, const std::string &);
+public:
+	/// Re-throw a caught exception, if any. Can only be called after thread exit.
+	void rethrow()
+	{
+		sanity_check(!isRunning());
+		if (m_exptr)
+			std::rethrow_exception(m_exptr);
+	}
+
+private:
+	// hide methods
+	LambdaThread(const std::string &name="") : Thread(name) {}
+	using Thread::start;
+
+	std::function<void()> m_fn;
+	std::exception_ptr m_exptr;
+
+	void *run()
+	{
+		try {
+			m_fn();
+		} catch(...) {
+			m_exptr = std::current_exception();
+		}
+		return nullptr;
+	};
+};
+
+/**
+ * Run a lambda in a separate thread.
+ *
+ * Exceptions will be caught.
+ * @param fn function to run
+ * @param thread_name name for thread
+ * @return thread object of type `LambdaThread`
+*/
+std::unique_ptr<LambdaThread> runInThread(const std::function<void()> &fn,
+	const std::string &thread_name = "")
+{
+	std::unique_ptr<LambdaThread> t(new LambdaThread(thread_name));
+	t->m_fn = fn;
+	t->start();
+	return t;
+}

src/threading/thread.h

@@ -59,6 +59,7 @@ public:
 	Thread(const std::string &name="");
 	virtual ~Thread();
 	DISABLE_CLASS_COPY(Thread)
+	// Note: class cannot be moved since other references exist
 
 	/*
 	 * Begins execution of a new thread at the pure virtual method Thread::run().

src/unittest/test.cpp

@@ -324,13 +324,8 @@ std::string TestBase::getTestTempDirectory()
 	if (!m_test_dir.empty())
 		return m_test_dir;
 
-	char buf[32];
-	porting::mt_snprintf(buf, sizeof(buf), "%08X", myrand());
-
-	m_test_dir = fs::TempPath() + DIR_DELIM "mttest_" + buf;
-	if (!fs::CreateDir(m_test_dir))
-		UASSERT(false);
-
+	m_test_dir = fs::CreateTempDir();
+	UASSERT(!m_test_dir.empty());
 	return m_test_dir;
 }