Fix lane {.name} setting application

The name of the lane was applied to the thread of the lane's creator instead of the lane's thread

3 files changed, 42 insertions, 36 deletions

diff --git a/src/lane.cpp b/src/lane.cpp
index 3f6f792..63efdb6 100644
--- a/src/lane.cpp
+++ b/src/lane.cpp
@@ -90,7 +90,8 @@ static LUAG_FUNC(lane_threadname)
     if (lua_gettop(L_) == 1) {
     lua_settop(L_, 1);
     STACK_CHECK_START_REL(L_, 0);
-    _lane->changeDebugName(kIdxTop);
+    _lane->storeDebugName(luaG_tostring(L_, kIdxTop));
+    _lane->applyDebugName();
     STACK_CHECK(L_, 0);
     return 0;
     } else if (lua_gettop(L_) == 0) {
@@ -708,6 +709,7 @@ static void lane_main(Lane* const lane_)
     }
 #endif // __PROSPERO__
 
+    lane_->applyDebugName();
     lua_State* const _L{ lane_->L };
     LuaError _rc{ LuaError::ERRRUN };
     if (lane_->status.load(std::memory_order_acquire) == Lane::Pending) { // nothing wrong happened during preparation, we can work
@@ -908,6 +910,19 @@ Lane::~Lane()
 
 // #################################################################################################
 
+void Lane::applyDebugName() const
+{
+    if constexpr (HAVE_DECODA_SUPPORT()) {
+        // to see VM name in Decoda debugger Virtual Machine window
+        luaG_pushstring(L, debugName);                                                             // L: ... "name"
+        lua_setglobal(L, "decoda_name");                                                           // L: ...
+    }
+    // and finally set the OS thread name
+    THREAD_SETNAME(debugName);
+}
+
+// #################################################################################################
+
 CancelResult Lane::cancel(CancelOp const op_, std::chrono::time_point<std::chrono::steady_clock> const until_, WakeLane const wakeLane_, int const hookCount_)
 {
     // this is a hook installed with lua_sethook: can't capture anything to be convertible to lua_Hook
@@ -963,30 +978,6 @@ CancelResult Lane::internalCancel(CancelRequest const rq_, std::chrono::time_poi
 
 // #################################################################################################
 
-void Lane::changeDebugName(StackIndex const nameIdx_)
-{
-    StackIndex const _nameIdx{ luaG_absindex(L, nameIdx_) };
-    luaL_checktype(L, _nameIdx, LUA_TSTRING);                                                      // L: ... "name" ...
-    STACK_CHECK_START_REL(L, 0);
-    // store a hidden reference in the registry to make sure the string is kept around even if a lane decides to manually change the "decoda_name" global...
-    kLaneNameRegKey.setValue(L, [idx = _nameIdx](lua_State* L_) { lua_pushvalue(L_, idx); });      // L: ... "name" ...
-    // keep a direct pointer on the string
-    {
-        std::lock_guard<std::mutex> _guard{ debugNameMutex };
-    debugName = luaG_tostring(L, _nameIdx);
-    }
-    if constexpr (HAVE_DECODA_SUPPORT()) {
-        // to see VM name in Decoda debugger Virtual Machine window
-        lua_pushvalue(L, _nameIdx);                                                                // L: ... "name" ... "name"
-        lua_setglobal(L, "decoda_name");                                                           // L: ... "name" ...
-    }
-    // and finally set the OS thread name
-    THREAD_SETNAME(debugName.data());
-    STACK_CHECK(L, 0);
-}
-
-// #################################################################################################
-
 //---
 // str= thread_status( lane )
 //
@@ -1183,6 +1174,24 @@ void Lane::startThread(int const priority_)
 
 // #################################################################################################
 
+void Lane::storeDebugName(std::string_view const& name_)
+{
+    STACK_CHECK_START_REL(L, 0);
+    // store a hidden reference in the registry to make sure the string is kept around even if a lane decides to manually change the "decoda_name" global...
+    kLaneNameRegKey.setValue(L, [name = name_](lua_State* L_) { luaG_pushstring(L_, name); });
+    STACK_CHECK(L, 0);
+    kLaneNameRegKey.pushValue(L);                                                                       // L: ... "name" ...
+    // keep a direct view on the stored string
+    {
+        std::lock_guard<std::mutex> _guard{ debugNameMutex };
+        debugName = luaG_tostring(L, kIdxTop);
+    }
+    lua_pop(L, 1);
+    STACK_CHECK(L, 0);
+}
+
+// #################################################################################################
+
 // take the results on the lane state stack and store them in our uservalue table, at numeric indices:
 // t[0] = nresults
 // t[i] = result #i
diff --git a/src/lane.hpp b/src/lane.hpp
index 29bf213..183c8bf 100644
--- a/src/lane.hpp
+++ b/src/lane.hpp
@@ -162,8 +162,8 @@ class Lane
 
     public:
 
+    void applyDebugName() const;
     CancelResult cancel(CancelOp op_, std::chrono::time_point<std::chrono::steady_clock> until_, WakeLane wakeLane_, int hookCount_);
-    void changeDebugName(StackIndex nameIdx_);
     void closeState()
     {
         lua_State* const _L{ S };
@@ -202,6 +202,7 @@ class Lane
     bool selfdestructRemove();
     void securizeDebugName(lua_State* L_);
     void startThread(int priority_);
+    void storeDebugName( std::string_view const& name_);
     [[nodiscard]]
     int storeResults(lua_State* L_);
     [[nodiscard]]
diff --git a/src/lanes.cpp b/src/lanes.cpp
index f32e7af..87f9a90 100644
--- a/src/lanes.cpp
+++ b/src/lanes.cpp
@@ -356,24 +356,20 @@ LUAG_FUNC(lane_new)
             // store the uservalue in the Lane full userdata
             lua_setiuservalue(L, StackIndex{ -2 }, UserValueIndex{ 1 });                           // L: ... lane
 
-            lua_State* const _L2{ lane->L };
-            STACK_CHECK_START_REL(_L2, 0);
             StackIndex const _name_idx{ lua_isnoneornil(L, kNameIdx) ? kIdxNone : kNameIdx };
-            std::string_view const _debugName{ (_name_idx > 0) ? luaG_tostring(L, _name_idx) : std::string_view{} };
+            std::string_view _debugName{ (_name_idx > 0) ? luaG_tostring(L, _name_idx) : std::string_view{} };
             if (!_debugName.empty())
             {
-                if (_debugName != "auto") {
-                    luaG_pushstring(_L2, _debugName);                                              // L: ... lane                                    L2: "<name>"
-                } else {
+                if (_debugName == "auto") {
                     lua_Debug _ar;
                     lua_pushvalue(L, kFuncIdx);                                                    // L: ... lane func
                     lua_getinfo(L, ">S", &_ar);                                                    // L: ... lane
-                    luaG_pushstring(_L2, "%s:%d", _ar.short_src, _ar.linedefined);                 // L: ... lane                                    L2: "<name>"
+                    luaG_pushstring(L, "%s:%d", _ar.short_src, _ar.linedefined);                   // L: ... lane "<name>"
+                    lua_replace(L, _name_idx);                                                     // L: ... lane
+                    _debugName = luaG_tostring(L, _name_idx);
                 }
-                lane->changeDebugName(kIdxTop);
-                lua_pop(_L2, 1);                                                                   // L: ... lane                                    L2:
+                lane->storeDebugName(_debugName);
             }
-            STACK_CHECK(_L2, 0);
             STACK_CHECK(L, 1);
         }