Merge pull request #843 from secondlife/luau-require-impl

Initial require implementation

9 files changed, 276 insertions, 13 deletions

diff --git a/indra/llcommon/lua_function.cpp b/indra/llcommon/lua_function.cpp
index 906a3f379c..a5f1f582d9 100644
--- a/indra/llcommon/lua_function.cpp
+++ b/indra/llcommon/lua_function.cpp
@@ -41,16 +41,9 @@ namespace
 
 int lluau::dostring(lua_State* L, const std::string& desc, const std::string& text)
 {
-    {
-        size_t bytecodeSize = 0;
-        // The char* returned by luau_compile() must be freed by calling free().
-        // Use unique_ptr so the memory will be freed even if luau_load() throws.
-        std::unique_ptr<char[], freer> bytecode{
-            luau_compile(text.data(), text.length(), nullptr, &bytecodeSize)};
-        auto r = luau_load(L, desc.data(), bytecode.get(), bytecodeSize, 0);
-        if (r != LUA_OK)
-            return r;
-    } // free bytecode
+    auto r = loadstring(L, desc, text);
+    if (r != LUA_OK)
+        return r;
 
     // It's important to pass LUA_MULTRET as the expected number of return
     // values: if we pass any fixed number, we discard any returned values
@@ -58,6 +51,16 @@ int lluau::dostring(lua_State* L, const std::string& desc, const std::string& te
     return lua_pcall(L, 0, LUA_MULTRET, 0);
 }
 
+int lluau::loadstring(lua_State *L, const std::string &desc, const std::string &text)
+{
+    size_t bytecodeSize = 0;
+    // The char* returned by luau_compile() must be freed by calling free().
+    // Use unique_ptr so the memory will be freed even if luau_load() throws.
+    std::unique_ptr<char[], freer> bytecode{
+        luau_compile(text.data(), text.length(), nullptr, &bytecodeSize)};
+    return luau_load(L, desc.data(), bytecode.get(), bytecodeSize, 0);
+}
+
 /*****************************************************************************
 *   Lua <=> C++ conversions
 *****************************************************************************/
@@ -426,8 +429,18 @@ void lua_pushllsd(lua_State* L, const LLSD& data)
 *****************************************************************************/
 LuaState::LuaState(script_finished_fn cb):
     mCallback(cb),
-    mState(luaL_newstate())
+    mState(nullptr)
 {
+    initLuaState();
+}
+
+void LuaState::initLuaState() 
+{
+    if (mState)
+    {
+        lua_close(mState);
+    }
+    mState = luaL_newstate();
     luaL_openlibs(mState);
     LuaFunction::init(mState);
     // Try to make print() write to our log.
diff --git a/indra/llcommon/lua_function.h b/indra/llcommon/lua_function.h
index eccc92ec09..08a2353d29 100644
--- a/indra/llcommon/lua_function.h
+++ b/indra/llcommon/lua_function.h
@@ -50,6 +50,7 @@ namespace lluau
     // rather than string_views because dostring() needs pointers to nul-
     // terminated char arrays.
     int dostring(lua_State* L, const std::string& desc, const std::string& text);
+    int loadstring(lua_State* L, const std::string& desc, const std::string& text);
 } // namespace lluau
 
 std::string lua_tostdstring(lua_State* L, int index);
@@ -72,6 +73,8 @@ public:
 
     ~LuaState();
 
+    void initLuaState();
+
     bool checkLua(const std::string& desc, int r);
 
     // expr() is for when we want to capture any results left on the stack
diff --git a/indra/llfilesystem/lldir.cpp b/indra/llfilesystem/lldir.cpp
index 69b23f9cf8..e3769c6afb 100644
--- a/indra/llfilesystem/lldir.cpp
+++ b/indra/llfilesystem/lldir.cpp
@@ -469,6 +469,7 @@ static std::string ELLPathToString(ELLPath location)
 		ENT(LL_PATH_DEFAULT_SKIN)
 		ENT(LL_PATH_FONTS)
 		ENT(LL_PATH_LAST)
+        ENT(LL_PATH_SCRIPTS)
 	;
 #undef ENT
 
@@ -588,6 +589,10 @@ std::string LLDir::getExpandedFilename(ELLPath location, const std::string& subd
 	case LL_PATH_FONTS:
 		prefix = add(getAppRODataDir(), "fonts");
 		break;
+
+    case LL_PATH_SCRIPTS:
+        prefix = add(getAppRODataDir(), "scripts");
+        break;
 		
 	default:
 		llassert(0);
diff --git a/indra/llfilesystem/lldir.h b/indra/llfilesystem/lldir.h
index b9a046ba33..7d418159d1 100644
--- a/indra/llfilesystem/lldir.h
+++ b/indra/llfilesystem/lldir.h
@@ -49,6 +49,7 @@ typedef enum ELLPath
 	LL_PATH_DEFAULT_SKIN = 17,
 	LL_PATH_FONTS = 18,
     LL_PATH_DUMP = 19,
+    LL_PATH_SCRIPTS = 20,
 	LL_PATH_LAST
 } ELLPath;
 
diff --git a/indra/newview/llfloaterluadebug.cpp b/indra/newview/llfloaterluadebug.cpp
index 3ebe40f80b..b63600e0e6 100644
--- a/indra/newview/llfloaterluadebug.cpp
+++ b/indra/newview/llfloaterluadebug.cpp
@@ -27,6 +27,7 @@
 
 #include "llfloaterluadebug.h"
 
+#include "llcheckboxctrl.h"
 #include "lllineeditor.h"
 #include "lltexteditor.h"
 #include "llviewermenufile.h" // LLFilePickerReplyThread
@@ -79,6 +80,7 @@ void LLFloaterLUADebug::onExecuteClicked()
     mResultOutput->setValue("");
 
     std::string cmd = mLineInput->getText();
+    cleanLuaState(); 
     LLLUAmanager::runScriptLine(mState, cmd, [this](int count, const LLSD& result)
         {
             completion(count, result);
@@ -109,6 +111,7 @@ void LLFloaterLUADebug::runSelectedScript(const std::vector<std::string> &filena
     if (!filepath.empty())
     {
         mScriptPath->setText(filepath);
+        cleanLuaState(); 
         LLLUAmanager::runScriptFile(mState, filepath, [this](int count, const LLSD& result)
         {
             completion(count, result);
@@ -140,3 +143,12 @@ void LLFloaterLUADebug::completion(int count, const LLSD& result)
         sep = ", ";
     }
 }
+
+void LLFloaterLUADebug::cleanLuaState() 
+{ 
+    if(getChild<LLCheckBoxCtrl>("clean_lua_state")->get()) 
+    {
+        //Reinit to clean lua_State
+        mState.initLuaState();
+    }
+}
diff --git a/indra/newview/llfloaterluadebug.h b/indra/newview/llfloaterluadebug.h
index 69b334ae2d..7418174570 100644
--- a/indra/newview/llfloaterluadebug.h
+++ b/indra/newview/llfloaterluadebug.h
@@ -58,6 +58,7 @@ class LLFloaterLUADebug :
 
 private:
     void completion(int count, const LLSD& result);
+    void cleanLuaState();
 
     LLTempBoundListener mOutConnection;
 
diff --git a/indra/newview/llluamanager.cpp b/indra/newview/llluamanager.cpp
index 33b996ab50..0c39f6c8df 100644
--- a/indra/newview/llluamanager.cpp
+++ b/indra/newview/llluamanager.cpp
@@ -46,6 +46,7 @@ extern LLUIListener sUIListener;
 #endif // ! LL_TEST
 
 #include <boost/algorithm/string/replace.hpp>
+#include <filesystem>
 
 #include "luau/luacode.h"
 #include "luau/lua.h"
@@ -259,8 +260,7 @@ void LLLUAmanager::runScriptFile(LuaState& L, const std::string& filename, scrip
 
         if (in_file.is_open()) 
         {
-            std::string text{std::istreambuf_iterator<char>(in_file),
-                             std::istreambuf_iterator<char>()};
+            std::string text{std::istreambuf_iterator<char>(in_file), {}};
             auto [count, result] = L.expr(filename, text);
             if (cb)
             {
@@ -353,3 +353,185 @@ void LLLUAmanager::runScriptOnLogin()
     runScriptFile(filename);
 #endif // ! LL_TEST
 }
+
+std::string read_file(const std::string &name)
+{
+    llifstream in_file;
+    in_file.open(name.c_str());
+
+    if (in_file.is_open())
+    {
+        std::string text {std::istreambuf_iterator<char>(in_file), {}};
+        return text;
+    }
+
+    return std::string();
+}
+
+LLRequireResolver::LLRequireResolver(lua_State *L, const std::string& path) : mPathToResolve(path), L(L)
+{
+    //Luau lua_Debug and lua_getinfo() are different compared to default Lua:
+    //see https://github.com/luau-lang/luau/blob/80928acb92d1e4b6db16bada6d21b1fb6fa66265/VM/include/lua.h
+    lua_Debug ar;
+    lua_getinfo(L, 1, "s", &ar);
+    mSourceChunkname = ar.source;
+
+    std::filesystem::path fs_path(mPathToResolve);
+    mPathToResolve = fs_path.lexically_normal().string();
+
+    if (fs_path.is_absolute())
+        luaL_argerrorL(L, 1, "cannot require a full path");
+}
+
+[[nodiscard]] LLRequireResolver::ResolvedRequire LLRequireResolver::resolveRequire(lua_State *L, std::string path)
+{
+    LLRequireResolver resolver(L, std::move(path));
+    ModuleStatus status = resolver.findModule();
+    if (status != ModuleStatus::FileRead)
+        return ResolvedRequire {status};
+    else
+        return ResolvedRequire {status, resolver.mAbsolutePath, resolver.mSourceCode};
+}
+
+LLRequireResolver::ModuleStatus LLRequireResolver::findModule()
+{
+    resolveAndStoreDefaultPaths();
+
+    // Put _MODULES table on stack for checking and saving to the cache
+    luaL_findtable(L, LUA_REGISTRYINDEX, "_MODULES", 1);
+
+    // Check if the module is already in _MODULES table, read from file otherwise
+    LLRequireResolver::ModuleStatus moduleStatus = findModuleImpl();
+
+    if (moduleStatus != LLRequireResolver::ModuleStatus::NotFound)
+        return moduleStatus;
+
+    if (std::filesystem::path(mPathToResolve).is_absolute())
+        return moduleStatus;
+
+    std::vector<std::string> lib_paths {gDirUtilp->getExpandedFilename(LL_PATH_SCRIPTS, "lua")};
+
+    for (const auto& path : lib_paths)
+    {
+        std::string absolutePathOpt = (std::filesystem::path(path) / mPathToResolve).u8string();
+
+        if (absolutePathOpt.empty())
+            luaL_errorL(L, "error requiring module");
+
+        mAbsolutePath = absolutePathOpt;
+
+        moduleStatus = findModuleImpl();
+
+        if (moduleStatus != LLRequireResolver::ModuleStatus::NotFound)
+            return moduleStatus;
+    }
+
+    return LLRequireResolver::ModuleStatus::NotFound;
+}
+
+LLRequireResolver::ModuleStatus LLRequireResolver::findModuleImpl()
+{
+    std::string possibleSuffixedPaths[] = {mAbsolutePath + ".luau", mAbsolutePath + ".lua"};
+
+     for (auto suffixedPath : possibleSuffixedPaths)
+    {
+         // Check _MODULES cache for module
+        lua_getfield(L, -1, suffixedPath.c_str());
+        if (!lua_isnil(L, -1))
+        {
+            return ModuleStatus::Cached;
+        }
+        lua_pop(L, 1);
+
+        // Try to read the matching file
+        std::string source = read_file(suffixedPath);
+        if (!source.empty())
+        {
+            mAbsolutePath = suffixedPath;
+            mSourceCode = source;
+            return ModuleStatus::FileRead;
+        }
+    }
+
+    return ModuleStatus::NotFound;
+}
+
+void LLRequireResolver::resolveAndStoreDefaultPaths()
+{
+    if (!std::filesystem::path(mPathToResolve).is_absolute())
+    {
+        mAbsolutePath = (std::filesystem::path((mSourceChunkname)).parent_path() / mPathToResolve).u8string();;
+    }
+    else
+    {
+        mAbsolutePath = mPathToResolve;
+    }
+}
+
+static int finishrequire(lua_State *L)
+{
+    if (lua_isstring(L, -1))
+        lua_error(L);
+
+    return 1;
+}
+
+lua_function(require, "require(module_name) : module_name can be fullpath or just the name, in both cases without .lua")
+{
+    std::string name = lua_tostdstring(L, 1);
+
+    LLRequireResolver::ResolvedRequire resolvedRequire = LLRequireResolver::resolveRequire(L, name);
+
+    if (resolvedRequire.status == LLRequireResolver::ModuleStatus::Cached) 
+    {
+        // remove _MODULES from stack
+        lua_remove(L, -2);
+        return finishrequire(L);
+    }
+    else if (resolvedRequire.status == LLRequireResolver::ModuleStatus::NotFound)
+        luaL_errorL(L, "error requiring module");
+
+    // module needs to run in a new thread, isolated from the rest
+    // note: we create ML on main thread so that it doesn't inherit environment of L
+    lua_State *GL = lua_mainthread(L);
+    lua_State *ML = lua_newthread(GL);
+    lua_xmove(GL, L, 1);
+
+    // new thread needs to have the globals sandboxed
+    luaL_sandboxthread(ML);
+
+    {
+        if (lluau::loadstring(ML, resolvedRequire.absolutePath.c_str(), resolvedRequire.sourceCode.c_str()) == LUA_OK)
+        {
+            int status = lua_resume(ML, L, 0);
+
+            if (status == LUA_OK)
+            {
+                if (lua_gettop(ML) == LUA_OK)
+                    lua_pushstring(ML, "module must return a value");
+                else if (!lua_istable(ML, -1) && !lua_isfunction(ML, -1))
+                    lua_pushstring(ML, "module must return a table or function");
+            }
+            else if (status == LUA_YIELD)
+            {
+                lua_pushstring(ML, "module can not yield");
+            }
+            else if (!lua_isstring(ML, -1))
+            {
+                lua_pushstring(ML, "unknown error while running module");
+            }
+        }
+    }
+    // there's now a return value on top of ML; L stack: _MODULES ML
+    lua_xmove(ML, L, 1);
+    lua_pushvalue(L, -1);
+    lua_setfield(L, -4, resolvedRequire.absolutePath.c_str());
+
+    //remove _MODULES from stack
+    lua_remove(L, -3);
+    // remove ML from stack
+    lua_remove(L, -2);
+    
+    // L stack: [module name] [result]
+    return finishrequire(L);
+}
diff --git a/indra/newview/llluamanager.h b/indra/newview/llluamanager.h
index 12284cd0e4..43950ccee4 100644
--- a/indra/newview/llluamanager.h
+++ b/indra/newview/llluamanager.h
@@ -33,6 +33,9 @@
 #include <string>
 #include <utility>                  // std::pair
 
+#include "luau/lua.h"
+#include "luau/lualib.h"
+
 class LuaState;
 
 class LLLUAmanager
@@ -81,4 +84,38 @@ public:
     static void runScriptOnLogin();
 };
 
+class LLRequireResolver
+{
+ public:
+    enum class ModuleStatus
+    {
+        Cached,
+        FileRead,
+        NotFound
+    };
+
+    struct ResolvedRequire
+    {
+        ModuleStatus status;
+        std::string absolutePath;
+        std::string sourceCode;
+    };
+
+    [[nodiscard]] ResolvedRequire static resolveRequire(lua_State *L, std::string path);
+
+    std::string mAbsolutePath;
+    std::string mSourceCode;
+
+ private:
+    std::string mPathToResolve;
+    std::string mSourceChunkname;
+
+    LLRequireResolver(lua_State *L, const std::string& path);
+
+    ModuleStatus findModule();
+    lua_State *L;
+
+    void resolveAndStoreDefaultPaths();
+    ModuleStatus findModuleImpl();
+};
 #endif
diff --git a/indra/newview/skins/default/xui/en/floater_lua_debug.xml b/indra/newview/skins/default/xui/en/floater_lua_debug.xml
index f03739f7c2..a028a1802c 100644
--- a/indra/newview/skins/default/xui/en/floater_lua_debug.xml
+++ b/indra/newview/skins/default/xui/en/floater_lua_debug.xml
@@ -25,6 +25,15 @@
      width="100">
       LUA string:
     </text>
+    <check_box
+     follows="left|bottom"
+     height="15"
+     label="Use clean lua_State"
+     layout="topleft"
+     top="10"
+     right ="-70"
+     name="clean_lua_state"
+     width="70"/>
     <line_editor
      border_style="line"
      border_thickness="1"