1 files changed, 483 insertions, 0 deletions
diff --git a/indra/newview/llluamanager.cpp b/indra/newview/llluamanager.cpp
new file mode 100644
index 0000000000..7fe5c1ece0
--- /dev/null
+++ b/indra/newview/llluamanager.cpp
@@ -0,0 +1,483 @@
+/**
+ * @file llluamanager.cpp
+ * @brief classes and functions for interfacing with LUA.
+ *
+ * $LicenseInfo:firstyear=2023&license=viewerlgpl$
+ * Second Life Viewer Source Code
+ * Copyright (C) 2023, Linden Research, Inc.
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation;
+ * version 2.1 of the License only.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
+ *
+ * Linden Research, Inc., 945 Battery Street, San Francisco, CA  94111  USA
+ * $/LicenseInfo$
+ *
+ */
+
+#include "llviewerprecompiledheaders.h"
+#include "llluamanager.h"
+
+#include "fsyspath.h"
+#include "llcoros.h"
+#include "llerror.h"
+#include "lleventcoro.h"
+#include "llsdutil.h"
+#include "llviewercontrol.h"
+#include "lua_function.h"
+#include "lualistener.h"
+#include "stringize.h"
+
+#include <boost/algorithm/string/replace.hpp>
+
+#include "luau/luacode.h"
+#include "luau/lua.h"
+#include "luau/luaconf.h"
+#include "luau/lualib.h"
+
+#include <sstream>
+#include <string_view>
+#include <vector>
+
+S32 LLLUAmanager::sAutorunScriptCount = 0;
+S32 LLLUAmanager::sScriptCount = 0;
+std::map<std::string, std::string> LLLUAmanager::sScriptNames;
+
+lua_function(sleep, "sleep(seconds): pause the running coroutine")
+{
+    lua_checkdelta(L, -1);
+    lua_Number seconds = lua_tonumber(L, -1);
+    lua_pop(L, 1);
+    llcoro::suspendUntilTimeout(narrow(seconds));
+    LuaState::getParent(L).set_interrupts_counter(0);
+    return 0;
+};
+
+// This function consumes ALL Lua stack arguments and returns concatenated
+// message string
+std::string lua_print_msg(lua_State* L, std::string_view level)
+{
+    // On top of existing Lua arguments, we're going to push tostring() and
+    // duplicate each existing stack entry so we can stringize each one.
+    lluau_checkstack(L, 2);
+    luaL_where(L, 1);
+    // start with the 'where' info at the top of the stack
+    std::ostringstream out;
+    out << lua_tostring(L, -1);
+    lua_pop(L, 1);
+    const char* sep = "";           // 'where' info ends with ": "
+    // now iterate over arbitrary args, calling Lua tostring() on each and
+    // concatenating with separators
+    for (int p = 1, top = lua_gettop(L); p <= top; ++p)
+    {
+        out << sep;
+        sep = " ";
+        // push Lua tostring() function -- note, semantically different from
+        // lua_tostring()!
+        lua_getglobal(L, "tostring");
+        // Now the stack is arguments 1 .. N, plus tostring().
+        // Push a copy of the argument at index p.
+        lua_pushvalue(L, p);
+        // pop tostring() and arg-p, pushing tostring(arg-p)
+        // (ignore potential error code from lua_pcall() because, if there was
+        // an error, we expect the stack top to be an error message -- which
+        // we'll print)
+        lua_pcall(L, 1, 1, 0);
+        out << lua_tostring(L, -1);
+        lua_pop(L, 1);
+    }
+    // pop everything
+    lua_settop(L, 0);
+    // capture message string
+    std::string msg{ out.str() };
+    // put message out there for any interested party (*koff* LLFloaterLUADebug *koff*)
+    LLEventPumps::instance().obtain("lua output").post(stringize(level, ": ", msg));
+
+    llcoro::suspend();
+    return msg;
+}
+
+lua_function(print_debug, "print_debug(args...): DEBUG level logging")
+{
+    LL_DEBUGS("Lua") << lua_print_msg(L, "DEBUG") << LL_ENDL;
+    return 0;
+}
+
+// also used for print(); see LuaState constructor
+lua_function(print_info, "print_info(args...): INFO level logging")
+{
+    LL_INFOS("Lua") << lua_print_msg(L, "INFO") << LL_ENDL;
+    return 0;
+}
+
+lua_function(print_warning, "print_warning(args...): WARNING level logging")
+{
+    LL_WARNS("Lua") << lua_print_msg(L, "WARN") << LL_ENDL;
+    return 0;
+}
+
+lua_function(post_on, "post_on(pumpname, data): post specified data to specified LLEventPump")
+{
+    lua_checkdelta(L, -2);
+    std::string pumpname{ lua_tostdstring(L, 1) };
+    LLSD data{ lua_tollsd(L, 2) };
+    lua_pop(L, 2);
+    LL_DEBUGS("Lua") << "post_on('" << pumpname << "', " << data << ")" << LL_ENDL;
+    LLEventPumps::instance().obtain(pumpname).post(data);
+    return 0;
+}
+
+lua_function(get_event_pumps,
+             "get_event_pumps():\n"
+             "Returns replypump, commandpump: names of LLEventPumps specific to this chunk.\n"
+             "Events posted to replypump are queued for get_event_next().\n"
+             "post_on(commandpump, ...) to engage LLEventAPI operations (see helpleap()).")
+{
+    lua_checkdelta(L, 2);
+    lluau_checkstack(L, 2);
+    auto& listener{ LuaState::obtainListener(L) };
+    // return the reply pump name and the command pump name on caller's lua_State
+    lua_pushstdstring(L, listener.getReplyName());
+    lua_pushstdstring(L, listener.getCommandName());
+    return 2;
+}
+
+lua_function(get_event_next,
+             "get_event_next():\n"
+             "Returns the next (pumpname, data) pair from the replypump whose name\n"
+             "is returned by get_event_pumps(). Blocks the calling chunk until an\n"
+             "event becomes available.")
+{
+    lua_checkdelta(L, 2);
+    lluau_checkstack(L, 2);
+    auto& listener{ LuaState::obtainListener(L) };
+    const auto& [pump, data]{ listener.getNext() };
+    lua_pushstdstring(L, pump);
+    lua_pushllsd(L, data);
+    LuaState::getParent(L).set_interrupts_counter(0);
+    return 2;
+}
+
+LLCoros::Future<LLLUAmanager::script_result>
+LLLUAmanager::startScriptFile(const std::string& filename)
+{
+    // Despite returning from startScriptFile(), we need this Promise to
+    // remain alive until the callback has fired.
+    auto promise{ std::make_shared<LLCoros::Promise<script_result>>() };
+    runScriptFile(filename, false,
+                  [promise](int count, LLSD result)
+                  { promise->set_value({ count, result }); });
+    return LLCoros::getFuture(*promise);
+}
+
+LLLUAmanager::script_result LLLUAmanager::waitScriptFile(const std::string& filename)
+{
+    return startScriptFile(filename).get();
+}
+
+void LLLUAmanager::runScriptFile(const std::string &filename, bool autorun,
+                                 script_result_fn result_cb)
+{
+    // A script_result_fn will be called when LuaState::expr() completes.
+    LLCoros::instance().launch(filename, [filename, autorun, result_cb]()
+    {
+        ScriptObserver observer(LLCoros::getName(), filename);
+        LLSD paths(gSavedSettings.getLLSD("LuaCommandPath"));
+        LL_DEBUGS("Lua") << "LuaCommandPath = " << paths << LL_ENDL;
+        // allow LuaCommandPath to be specified relative to install dir
+        ScriptCommand command(filename, paths, gDirUtilp->getAppRODataDir());
+        auto error = command.error();
+        if (! error.empty())
+        {
+            if (result_cb)
+            {
+                result_cb(-1, error);
+            }
+            return;
+        }
+
+        llifstream in_file;
+        in_file.open(command.script);
+        // At this point, since ScriptCommand did not report an error, we
+        // should be able to assume that 'script' exists. If we can't open it,
+        // something else is wrong?!
+        llassert(in_file.is_open());
+        if (autorun)
+        {
+            sAutorunScriptCount++;
+        }
+        sScriptCount++;
+
+        LuaState L;
+        std::string text{std::istreambuf_iterator<char>(in_file), {}};
+        auto [count, result] = L.expr(command.script, text, command.args);
+        if (result_cb)
+        {
+            result_cb(count, result);
+        }
+    });
+}
+
+LLCoros::Future<LLLUAmanager::script_result>
+LLLUAmanager::startScriptLine(const std::string& chunk)
+{
+    // Despite returning from startScriptLine(), we need this Promise to
+    // remain alive until the callback has fired.
+    auto promise{ std::make_shared<LLCoros::Promise<script_result>>() };
+    runScriptLine(chunk,
+                  [promise](int count, LLSD result)
+                  { promise->set_value({ count, result }); });
+    return LLCoros::getFuture(*promise);
+}
+
+LLLUAmanager::script_result LLLUAmanager::waitScriptLine(const std::string& chunk)
+{
+    return startScriptLine(chunk).get();
+}
+
+void LLLUAmanager::runScriptLine(const std::string& chunk, script_result_fn result_cb)
+{
+    // find a suitable abbreviation for the chunk string
+    std::string shortchunk{ chunk };
+    const size_t shortlen = 40;
+    std::string::size_type eol = shortchunk.find_first_of("\r\n");
+    if (eol != std::string::npos)
+        shortchunk = shortchunk.substr(0, eol);
+    if (shortchunk.length() > shortlen)
+        shortchunk = stringize(shortchunk.substr(0, shortlen), "...");
+
+    std::string desc{ "lua: " + shortchunk };
+    LLCoros::instance().launch(desc, [desc, chunk, result_cb]()
+    {
+        LuaState L;
+        auto [count, result] = L.expr(desc, chunk);
+        if (result_cb)
+        {
+            result_cb(count, result);
+        }
+    });
+}
+
+std::string read_file(const std::string &name)
+{
+    llifstream in_file;
+    in_file.open(name.c_str());
+
+    if (in_file.is_open())
+    {
+        return std::string{std::istreambuf_iterator<char>(in_file), {}};
+    }
+
+    return {};
+}
+
+lua_function(require, "require(module_name) : load module_name.lua from known places")
+{
+    lua_checkdelta(L);
+    std::string name = lua_tostdstring(L, 1);
+    lua_pop(L, 1);
+
+    // resolveRequire() does not return in case of error.
+    LLRequireResolver::resolveRequire(L, name);
+
+    // resolveRequire() returned the newly-loaded module on the stack top.
+    // Return it.
+    return 1;
+}
+
+// push loaded module or throw Lua error
+void LLRequireResolver::resolveRequire(lua_State *L, std::string path)
+{
+    LLRequireResolver resolver(L, std::move(path));
+    // findModule() pushes the loaded module or throws a Lua error.
+    resolver.findModule();
+}
+
+LLRequireResolver::LLRequireResolver(lua_State *L, const std::string& path) :
+    mPathToResolve(fsyspath(path).lexically_normal()),
+    L(L)
+{
+    mSourceDir = lluau::source_path(L).parent_path();
+
+    if (mPathToResolve.is_absolute())
+        luaL_argerrorL(L, 1, "cannot require a full path");
+}
+
+// push the loaded module or throw a Lua error
+void LLRequireResolver::findModule()
+{
+    // If mPathToResolve is absolute, this replaces mSourceDir.
+    auto absolutePath = (mSourceDir / mPathToResolve).u8string();
+
+    // Push _MODULES table on stack for checking and saving to the cache
+    luaL_findtable(L, LUA_REGISTRYINDEX, "_MODULES", 1);
+    // Remove that stack entry no matter how we exit
+    LuaRemover rm_MODULES(L, -1);
+
+    // Check if the module is already in _MODULES table, read from file
+    // otherwise.
+    // findModuleImpl() pushes module if found, nothing if not, may throw Lua
+    // error.
+    if (findModuleImpl(absolutePath))
+        return;
+
+    // not already cached - prep error message just in case
+    auto fail{
+        [L=L, path=mPathToResolve.u8string()]()
+        { luaL_error(L, "could not find require('%s')", path.data()); }};
+
+    if (mPathToResolve.is_absolute())
+    {
+        // no point searching known directories for an absolute path
+        fail();
+    }
+
+    LLSD lib_paths(gSavedSettings.getLLSD("LuaRequirePath"));
+    LL_DEBUGS("Lua") << "LuaRequirePath = " << lib_paths << LL_ENDL;
+    for (const auto& path : llsd::inArray(lib_paths))
+    {
+        // if path is already absolute, operator/() preserves it
+        auto abspath(fsyspath(gDirUtilp->getAppRODataDir()) / path.asString());
+        std::string absolutePathOpt = (abspath / mPathToResolve).u8string();
+
+        if (absolutePathOpt.empty())
+            luaL_error(L, "error requiring module '%s'", mPathToResolve.u8string().data());
+
+        if (findModuleImpl(absolutePathOpt))
+            return;
+    }
+
+    // not found
+    fail();
+}
+
+// expects _MODULES table on stack top (and leaves it there)
+// - if found, pushes loaded module and returns true
+// - not found, pushes nothing and returns false
+// - may throw Lua error
+bool LLRequireResolver::findModuleImpl(const std::string& absolutePath)
+{
+    std::string possibleSuffixedPaths[] = {absolutePath + ".luau", absolutePath + ".lua"};
+
+    for (const auto& suffixedPath : possibleSuffixedPaths)
+    {
+         // Check _MODULES cache for module
+        lua_getfield(L, -1, suffixedPath.data());
+        if (!lua_isnil(L, -1))
+        {
+            return true;
+        }
+        lua_pop(L, 1);
+
+        // Try to read the matching file
+        std::string source = read_file(suffixedPath);
+        if (!source.empty())
+        {
+            // Try to run the loaded source. This will leave either a string
+            // error message or the module contents on the stack top.
+            runModule(suffixedPath, source);
+
+            // If the stack top is an error message string, raise it.
+            if (lua_isstring(L, -1))
+                lua_error(L);
+
+            // duplicate the new module: _MODULES newmodule newmodule
+            lua_pushvalue(L, -1);
+            // store _MODULES[found path] = newmodule
+            lua_setfield(L, -3, suffixedPath.data());
+
+            return true;
+        }
+    }
+
+    return false;
+}
+
+// push string error message or new module
+void LLRequireResolver::runModule(const std::string& desc, const std::string& code)
+{
+    // Here we just loaded a new module 'code', need to run it and get its result.
+    lua_State *ML = lua_mainthread(L);
+
+    {
+        // If loadstring() returns (! LUA_OK) then there's an error message on
+        // the stack. If it returns LUA_OK then the newly-loaded module code
+        // is on the stack.
+        LL_DEBUGS("Lua") << "Loading module " << desc << LL_ENDL;
+        if (lluau::loadstring(ML, desc, code) != LUA_OK)
+        {
+            // error message on stack top
+            LL_DEBUGS("Lua") << "Error loading module " << desc << ": "
+                             << lua_tostring(ML, -1) << LL_ENDL;
+            lua_pushliteral(ML, "loadstring: ");
+            // stack contains error, "loadstring: "
+            // swap: insert stack top at position -2
+            lua_insert(ML, -2);
+            // stack contains "loadstring: ", error
+            lua_concat(ML, 2);
+            // stack contains "loadstring: " + error
+        }
+        else                        // module code on stack top
+        {
+            // push debug module
+            lua_getglobal(ML, "debug");
+            // push debug.traceback
+            lua_getfield(ML, -1, "traceback");
+            // stack contains module code, debug, debug.traceback
+            // ditch debug
+            lua_replace(ML, -2);
+            // stack contains module code, debug.traceback
+            // swap: insert stack top at position -2
+            lua_insert(ML, -2);
+            // stack contains debug.traceback, module code
+            LL_DEBUGS("Lua") << "Loaded module " << desc << ", running" << LL_ENDL;
+            // no arguments, one return value
+            // pass debug.traceback as the error function
+            int status = lua_pcall(ML, 0, 1, -2);
+            // lua_pcall() has popped the module code and replaced it with its
+            // return value. Regardless of status or the type of the stack
+            // top, get rid of debug.traceback on the stack.
+            lua_remove(ML, -2);
+
+            if (status == LUA_OK)
+            {
+                auto top{ lua_gettop(ML) };
+                std::string type{ (top == 0)? "nothing"
+                                  : lua_typename(ML, lua_type(ML, -1)) };
+                LL_DEBUGS("Lua") << "Module " << desc << " returned " << type << LL_ENDL;
+                if ((top == 0) || ! (lua_istable(ML, -1) || lua_isfunction(ML, -1)))
+                {
+                    lua_pushfstring(ML, "module %s must return a table or function, not %s",
+                                    desc.data(), type.data());
+                }
+            }
+            else if (status == LUA_YIELD)
+            {
+                LL_DEBUGS("Lua") << "Module " << desc << " yielded" << LL_ENDL;
+                lua_pushfstring(ML, "module %s can not yield", desc.data());
+            }
+            else
+            {
+                llassert(lua_isstring(ML, -1));
+                LL_DEBUGS("Lua") << "Module " << desc << " error: "
+                                 << lua_tostring(ML, -1) << LL_ENDL;
+            }
+        }
+    }
+    // There's now a return value (string error message or module) on top of ML.
+    // Move return value to L's stack.
+    if (ML != L)
+    {
+        lua_xmove(ML, L, 1);
+    }
+}