From c6012a95bd8181dbda7cb770f6ec42e0498aa2c8 Mon Sep 17 00:00:00 2001 From: Mattes D Date: Wed, 17 Jun 2015 15:21:20 +0200 Subject: LuaState: Added support for config-style usage. Globals and table values can be queried from the Lua state easily. Use perfect forwarding. --- src/Bindings/LuaState.cpp | 83 ++++++++++++++++++++++---- src/Bindings/LuaState.h | 149 ++++++++++++++++++++++++++++++++++++++-------- src/Defines.h | 18 +++--- 3 files changed, 207 insertions(+), 43 deletions(-) (limited to 'src') diff --git a/src/Bindings/LuaState.cpp b/src/Bindings/LuaState.cpp index 232432a99..9814d1c85 100644 --- a/src/Bindings/LuaState.cpp +++ b/src/Bindings/LuaState.cpp @@ -211,23 +211,31 @@ void cLuaState::AddPackagePath(const AString & a_PathVariable, const AString & a -bool cLuaState::LoadFile(const AString & a_FileName) +bool cLuaState::LoadFile(const AString & a_FileName, bool a_LogWarnings) { ASSERT(IsValid()); // Load the file: int s = luaL_loadfile(m_LuaState, a_FileName.c_str()); - if (ReportErrors(s)) + if (s != 0) { - LOGWARNING("Can't load %s because of an error in file %s", m_SubsystemName.c_str(), a_FileName.c_str()); + if (a_LogWarnings) + { + LOGWARNING("Can't load %s because of a load error in file %s: %d (%s)", m_SubsystemName.c_str(), a_FileName.c_str(), s, lua_tostring(m_LuaState, -1)); + } + lua_pop(m_LuaState, 1); return false; } // Execute the globals: s = lua_pcall(m_LuaState, 0, LUA_MULTRET, 0); - if (ReportErrors(s)) + if (s != 0) { - LOGWARNING("Error in %s in file %s", m_SubsystemName.c_str(), a_FileName.c_str()); + if (a_LogWarnings) + { + LOGWARNING("Can't load %s because of an initialization error in file %s: %d (%s)", m_SubsystemName.c_str(), a_FileName.c_str(), s, lua_tostring(m_LuaState, -1)); + } + lua_pop(m_LuaState, 1); return false; } @@ -446,6 +454,18 @@ void cLuaState::Push(const cPlayer * a_Player) +void cLuaState::Push(const cLuaState::cRef & a_Ref) +{ + ASSERT(IsValid()); + + lua_rawgeti(m_LuaState, LUA_REGISTRYINDEX, static_cast(a_Ref)); + m_NumCurrentFunctionArgs += 1; +} + + + + + void cLuaState::Push(const HTTPRequest * a_Request) { ASSERT(IsValid()); @@ -765,14 +785,17 @@ bool cLuaState::GetStackValue(int a_StackPos, double & a_ReturnedVal) -bool cLuaState::GetStackValue(int a_StackPos, float & a_ReturnedVal) +bool cLuaState::GetStackValue(int a_StackPos, eBlockFace & a_ReturnedVal) { - if (lua_isnumber(m_LuaState, a_StackPos)) + if (!lua_isnumber(m_LuaState, a_StackPos)) { - a_ReturnedVal = static_cast(tolua_tonumber(m_LuaState, a_StackPos, a_ReturnedVal)); - return true; + return false; } - return false; + a_ReturnedVal = static_cast(Clamp( + static_cast(tolua_tonumber(m_LuaState, a_StackPos, a_ReturnedVal)), + static_cast(BLOCK_FACE_MIN), static_cast(BLOCK_FACE_MAX)) + ); + return true; } @@ -796,6 +819,46 @@ bool cLuaState::GetStackValue(int a_StackPos, eWeather & a_ReturnedVal) +bool cLuaState::GetStackValue(int a_StackPos, float & a_ReturnedVal) +{ + if (lua_isnumber(m_LuaState, a_StackPos)) + { + a_ReturnedVal = static_cast(tolua_tonumber(m_LuaState, a_StackPos, a_ReturnedVal)); + return true; + } + return false; +} + + + + + +cLuaState::cStackValue cLuaState::WalkToValue(const AString & a_Name) +{ + auto path = StringSplit(a_Name, "."); + lua_pushvalue(m_LuaState, -1); // Copy the stack value into the "working area" + for (const auto & elem: path) + { + // If the value is not a table, bail out (error): + if (!lua_istable(m_LuaState, -1)) + { + lua_pop(m_LuaState, 1); + return cStackValue(); + } + + // Get the next part of the path: + lua_getfield(m_LuaState, -1, elem.c_str()); + + // Remove the previous value from the stack (keep only the new one): + lua_remove(m_LuaState, -2); + } // for elem - path[] + return std::move(cStackValue(*this)); +} + + + + + bool cLuaState::CallFunction(int a_NumResults) { ASSERT (m_NumCurrentFunctionArgs >= 0); // A function must be pushed to stack first diff --git a/src/Bindings/LuaState.h b/src/Bindings/LuaState.h index 8a3411d30..f6addad11 100644 --- a/src/Bindings/LuaState.h +++ b/src/Bindings/LuaState.h @@ -78,11 +78,14 @@ public: bool IsValid(void) const {return (m_Ref != LUA_REFNIL); } /** Allows to use this class wherever an int (i. e. ref) is to be used */ - operator int(void) const { return m_Ref; } - + explicit operator int(void) const { return m_Ref; } + protected: cLuaState * m_LuaState; int m_Ref; + + // Remove the copy-constructor: + cRef(const cRef &) = delete; } ; @@ -98,6 +101,12 @@ public: { } + cTableRef(const cRef & a_TableRef, const char * a_FnName) : + m_TableRef(static_cast(a_TableRef)), + m_FnName(a_FnName) + { + } + int GetTableRef(void) const { return m_TableRef; } const char * GetFnName(void) const { return m_FnName; } } ; @@ -111,6 +120,61 @@ public: static const cRet Return; // Use this constant to delimit function args from return values for cLuaState::Call() + /** A RAII class for values pushed onto the Lua stack. + Will pop the value off the stack in the destructor. */ + class cStackValue + { + public: + cStackValue(void): + m_LuaState(nullptr) + { + } + + cStackValue(cLuaState & a_LuaState): + m_LuaState(a_LuaState) + { + m_StackLen = lua_gettop(a_LuaState); + } + + cStackValue(cStackValue && a_Src): + m_LuaState(nullptr), + m_StackLen(-1) + { + std::swap(m_LuaState, a_Src.m_LuaState); + std::swap(m_StackLen, a_Src.m_StackLen); + } + + ~cStackValue() + { + if (m_LuaState != nullptr) + { + auto top = lua_gettop(m_LuaState); + ASSERT(m_StackLen == top); + lua_pop(m_LuaState, 1); + } + } + + void Set(cLuaState & a_LuaState) + { + m_LuaState = a_LuaState; + m_StackLen = lua_gettop(a_LuaState); + } + + bool IsValid(void) const + { + return (m_LuaState != nullptr); + } + + protected: + lua_State * m_LuaState; + + int m_StackLen; + + // Remove the copy-constructor: + cStackValue(const cStackValue &) = delete; + }; + + /** Creates a new instance. The LuaState is not initialized. a_SubsystemName is used for reporting problems in the console, it is "plugin %s" for plugins, or "LuaScript" for the cLuaScript template @@ -151,10 +215,9 @@ public: void AddPackagePath(const AString & a_PathVariable, const AString & a_Path); /** Loads the specified file - Returns false and logs a warning to the console if not successful (but the LuaState is kept open). - m_SubsystemName is displayed in the warning log message. - */ - bool LoadFile(const AString & a_FileName); + Returns false and optionally logs a warning to the console if not successful (but the LuaState is kept open). + m_SubsystemName is displayed in the warning log message. */ + bool LoadFile(const AString & a_FileName, bool a_LogWarnings = true); /** Returns true if a_FunctionName is a valid Lua function that can be called */ bool HasFunction(const char * a_FunctionName); @@ -169,6 +232,7 @@ public: void Push(const char * a_Value); void Push(const cItems & a_Items); void Push(const cPlayer * a_Player); + void Push(const cRef & a_Ref); void Push(const HTTPRequest * a_Request); void Push(const HTTPTemplateRequest * a_Request); void Push(const Vector3d & a_Vector); @@ -188,12 +252,13 @@ public: // GetStackValue() retrieves the value at a_StackPos, if it is a valid type. If not, a_Value is unchanged. // Returns whether value was changed - // Enum values are clamped to their allowed range. + // Enum values are checked for their allowed values and fail if the value is not assigned. bool GetStackValue(int a_StackPos, AString & a_Value); bool GetStackValue(int a_StackPos, bool & a_Value); bool GetStackValue(int a_StackPos, cPluginManager::CommandResult & a_Result); bool GetStackValue(int a_StackPos, cRef & a_Ref); bool GetStackValue(int a_StackPos, double & a_Value); + bool GetStackValue(int a_StackPos, eBlockFace & a_Value); bool GetStackValue(int a_StackPos, eWeather & a_Value); bool GetStackValue(int a_StackPos, float & a_ReturnedVal); @@ -202,21 +267,53 @@ public: bool GetStackValue(int a_StackPos, T & a_ReturnedVal, typename std::enable_if::value>::type * unused = nullptr) { UNUSED(unused); - if (lua_isnumber(m_LuaState, a_StackPos)) + if (!lua_isnumber(m_LuaState, a_StackPos)) // Also accepts strings representing a number: http://pgl.yoyo.org/luai/i/lua_isnumber { - lua_Number Val = tolua_tonumber(m_LuaState, a_StackPos, a_ReturnedVal); - if (Val > std::numeric_limits::max()) - { - return false; - } - if (Val < std::numeric_limits::min()) - { - return false; - } - a_ReturnedVal = static_cast(Val); - return true; + return false; } - return false; + lua_Number Val = lua_tonumber(m_LuaState, a_StackPos); + if (Val > std::numeric_limits::max()) + { + return false; + } + if (Val < std::numeric_limits::min()) + { + return false; + } + a_ReturnedVal = static_cast(Val); + return true; + } + + /** Pushes the named value in the table at the top of the stack. + a_Name may be a path containing multiple table levels, such as "_G.cChatColor.Blue". + If the value is found, it is pushed on top of the stack and the returned cStackValue is valid. + If the value is not found, the stack is unchanged and the returned cStackValue is invalid. */ + cStackValue WalkToValue(const AString & a_Name); + + /** Retrieves the named value in the table at the top of the Lua stack. + a_Name may be a path containing multiple table levels, such as "_G.cChatColor.Blue". + Returns true if the value was successfully retrieved, false on error. */ + template bool GetNamedValue(const AString & a_Name, T & a_Value) + { + auto stk = WalkToValue(a_Name); + if (!stk.IsValid()) + { + // Name not found + return false; + } + return GetStackValue(-1, a_Value); + } + + /** Retrieves the named global value. a_Name may be a path containing multiple table levels, such as "_G.cChatColor.Blue". + Returns true if the value was successfully retrieved, false on error. */ + template bool GetNamedGlobal(const AString & a_Name, T & a_Value) + { + // Push the globals table onto the stack and make it RAII-removed: + lua_getglobal(m_LuaState, "_G"); + cStackValue stk(*this); + + // Get the named global: + return GetNamedValue(a_Name, a_Value); } // Include the auto-generated Push and GetStackValue() functions: @@ -229,12 +326,12 @@ public: template bool Call(const FnT & a_Function, Args &&... args) { - if (!PushFunction(a_Function)) + if (!PushFunction(std::forward(a_Function))) { // Pushing the function failed return false; } - return PushCallPop(args...); + return PushCallPop(std::forward(args)...); } /** Retrieves a list of values from the Lua stack, starting at the specified index. */ @@ -343,10 +440,10 @@ protected: /** Variadic template recursor: More params to push. Push them and recurse. */ template - inline bool PushCallPop(T a_Param, Args &&... args) + inline bool PushCallPop(T && a_Param, Args &&... args) { - Push(a_Param); - return PushCallPop(args...); + Push(std::forward(a_Param)); + return PushCallPop(std::forward(args)...); } /** Variadic template terminator: If there's nothing more to push, but return values to collect, call the function and collect the returns. */ @@ -363,7 +460,7 @@ protected: } // Collect the return values: - GetStackValues(-NumReturns, args...); + GetStackValues(-NumReturns, std::forward(args)...); lua_pop(m_LuaState, NumReturns); // All successful: diff --git a/src/Defines.h b/src/Defines.h index b167f69e3..f3b742e09 100644 --- a/src/Defines.h +++ b/src/Defines.h @@ -29,16 +29,16 @@ enum -/// Block face constants, used in PlayerDigging and PlayerBlockPlacement packets and bbox collision calc +/** Block face constants, used in PlayerDigging and PlayerBlockPlacement packets and bbox collision calc */ enum eBlockFace { BLOCK_FACE_NONE = -1, // Interacting with no block face - swinging the item in the air - BLOCK_FACE_XM = 4, // Interacting with the X- face of the block - BLOCK_FACE_XP = 5, // Interacting with the X+ face of the block - BLOCK_FACE_YM = 0, // Interacting with the Y- face of the block - BLOCK_FACE_YP = 1, // Interacting with the Y+ face of the block - BLOCK_FACE_ZM = 2, // Interacting with the Z- face of the block - BLOCK_FACE_ZP = 3, // Interacting with the Z+ face of the block + BLOCK_FACE_XM = 4, // Interacting with the X- face of the block + BLOCK_FACE_XP = 5, // Interacting with the X+ face of the block + BLOCK_FACE_YM = 0, // Interacting with the Y- face of the block + BLOCK_FACE_YP = 1, // Interacting with the Y+ face of the block + BLOCK_FACE_ZM = 2, // Interacting with the Z- face of the block + BLOCK_FACE_ZP = 3, // Interacting with the Z+ face of the block // Synonyms using the (deprecated) world directions: BLOCK_FACE_BOTTOM = BLOCK_FACE_YM, // Interacting with the bottom face of the block @@ -47,6 +47,10 @@ enum eBlockFace BLOCK_FACE_SOUTH = BLOCK_FACE_ZP, // Interacting with the southern face of the block BLOCK_FACE_WEST = BLOCK_FACE_XM, // Interacting with the western face of the block BLOCK_FACE_EAST = BLOCK_FACE_XP, // Interacting with the eastern face of the block + + // Bounds, used for range-checking: + BLOCK_FACE_MIN = -1, + BLOCK_FACE_MAX = 5, } ; -- cgit v1.2.3