First attempt at error-resistant /cpl directive

Config/DefaultEditorPerProjectUserSettings.ini

@@ -13,5 +13,5 @@ RestoreOpenAssetTabsOnRestart=AlwaysRestore
 AutoSaveWarningInSeconds=0
 
 [/Script/Integration.lxProjectSettings]
-ActiveServer=/Game/Luprex/KnownServers/SS_Localhost.SS_Localhost
+ActiveServer=/Game/Luprex/KnownServers/SS_Standalone.SS_Standalone
 

luprex/cpp/core/luastack.cpp

@@ -77,6 +77,7 @@ lua_State *LuaCoreStack::newstate (lua_Alloc allocf) {
     LS.rawset(LuaRegistry, "persist", LuaNewTable);
     LS.rawset(LuaRegistry, "unpersist", LuaNewTable);
     LS.rawset(LuaRegistry, "funcnames", LuaNewTable);
+    LS.rawset(LuaRegistry, "sourcedb", LuaNewTable);
 
     // Tag the registry and global environment with their tabletypes.
     LS.settabletype(LuaRegistry, LUA_TT_REGISTRY);

luprex/cpp/core/source.cpp

@@ -132,16 +132,6 @@ static void get_info_table(LuaCoreStack &LS, LuaSlot db, LuaSlot info, const eng
     LS.rawset(info, "name", fn);
 }
 
-static void calculate_loadresult(LuaCoreStack &LS0, LuaSlot info, const eng::string &fn, const eng::string &code) {
-    LuaVar loadresult;
-    LuaExtStack LS(LS0.state(), loadresult);
-    if (code == "") {
-        LS.rawset(info, "loadresult", "missing or empty source file");
-    } else {
-        LS.load(loadresult, code, fn);
-        LS.rawset(info, "loadresult", loadresult);
-    }
-}
 
 void SourceDB::diff(const SourceDB &auth, StreamBuffer *sb) {
     LuaVar sdb, sfn, sinfo, shash, sseq;
@@ -202,8 +192,8 @@ void SourceDB::diff(const SourceDB &auth, StreamBuffer *sb) {
 
 bool SourceDB::patch(StreamBuffer *sb, DebugCollector *dbc) {
     lua_State *L = lua_state_;
-    LuaVar db, info;
+    LuaVar db, info, closure;
-    LuaExtStack LS(L, db, info);
+    LuaExtStack LS(L, db, info, closure);
     LS.rawget(db, LuaRegistry, "sourcedb");
     int nupdates = sb->read_int32();
     for (int i = 0; i < nupdates; i++) {
@@ -219,24 +209,27 @@ bool SourceDB::patch(StreamBuffer *sb, DebugCollector *dbc) {
             if (code != "\001") {
                 LS.rawset(info, "code", code);
                 LS.rawset(info, "hash", util::hash_to_hex(util::hash_string(code)));
-                calculate_loadresult(LS, info, fn, code);
+                LS.load(closure, code, fn);
+                LS.rawset(info, "loadresult", closure);
             }
         }
     }
+    if (nupdates > 0) rebuild();
     return (nupdates > 0);
 }
 
 void SourceDB::set(const eng::string &fn, const eng::string &code, int sequence) {
     lua_State *L = lua_state_;
-    LuaVar db, info;
+    LuaVar db, info, closure;
-    LuaExtStack LS(L, db, info);
+    LuaExtStack LS(L, db, info, closure);
     LS.rawget(db, LuaRegistry, "sourcedb");
     get_info_table(LS, db, info, fn);
     LS.rawset(info, "sequence", sequence);
     LS.rawset(info, "code", code);
     LS.rawset(info, "fingerprint", "");
     LS.rawset(info, "hash", util::hash_to_hex(util::hash_string(code)));
-    calculate_loadresult(LS, info, fn, code);
+    LS.load(closure, code, fn);
+    LS.rawset(info, "loadresult", closure);
 }
 
 eng::string SourceDB::get(const eng::string &fn) {
@@ -262,19 +255,15 @@ eng::string SourceDB::get(const eng::string &fn) {
     return util::ss(seqno, ":", ccode, ":", cloadresult);
 }
 
-void SourceDB::update(const util::LuaSourceVec &source) {
+eng::string SourceDB::update(const util::LuaSourceVec &source) {
     lua_State *L = lua_state_;
-    LuaVar sourcedb, info;
+    LuaVar newsourcedb, oldsourcedb, info, closure;
-    LuaExtStack LS(L, sourcedb, info);
+    LuaExtStack LS(L, newsourcedb, oldsourcedb, info, closure);
 
-    // Get and clear the source database.
+    eng::ostringstream errors;
-    LS.rawget(sourcedb, LuaRegistry, "sourcedb");
-    if (!LS.istable(sourcedb)) {
-        LS.newtable(sourcedb);
-        LS.rawset(LuaRegistry, "sourcedb", sourcedb);
-    }
-    LS.cleartable(sourcedb, true);
 
+    // Step one.  Build the new sourcedb.
+    LS.newtable(newsourcedb);
     for (int i = 0; i < int(source.size()); i++) {
         const eng::string &file = source[i].first;
         const eng::string &code = source[i].second;
@@ -283,9 +272,32 @@ void SourceDB::update(const util::LuaSourceVec &source) {
         LS.rawset(info, "code", code);
         LS.rawset(info, "hash", util::hash_to_hex(util::hash_string(code)));
         LS.rawset(info, "sequence", i + 1);
-        calculate_loadresult(LS, info, file, code);
+        LS.load(closure, code, file);
-        LS.rawset(sourcedb, file, info);
+        LS.rawset(info, "loadresult", closure);
+        if (LS.isstring(closure)) {
+            errors << file << ":" << LS.ckstring(closure) << std::endl;
+        }
+        LS.rawset(newsourcedb, file, info);
     }
+
+    // If there were compile errors, return the errors and don't update the env.
+    if (!errors.view().empty()) {
+        return errors.str();
+    }
+
+    // Cache the old source database and store the new one.
+    LS.rawget(oldsourcedb, LuaRegistry, "sourcedb");
+    LS.rawset(LuaRegistry, "sourcedb", newsourcedb);
+
+    // Rebuild the source database.
+    eng::string rebuild_errors = rebuild();
+
+    // Restore the old state, if there were errors.
+    if (!rebuild_errors.empty()) {
+        LS.rawset(LuaRegistry, "sourcedb", oldsourcedb);
+        rebuild();
+    }
+    return rebuild_errors;
 }
 
 // Delete everything from the global environment.
@@ -411,14 +423,11 @@ eng::string SourceDB::get_source(const eng::string &fn)
     return LS.ckstring(code);
 }
 
-
 eng::vector<eng::string> SourceDB::modules() {
     eng::vector<eng::string> result;
     LuaVar sourcedb, key, info, seq;
     LuaExtStack LS(lua_state_, sourcedb, key, info, seq);
 
-    result.push_back("CORE");
-
     // Get the source database.
     LS.rawget(sourcedb, LuaRegistry, "sourcedb");
     if (!LS.istable(sourcedb)) {
@@ -439,35 +448,38 @@ eng::vector<eng::string> SourceDB::modules() {
     return result;
 }
 
-void SourceDB::rebuild_core() {
+eng::string SourceDB::rebuild_module(const eng::string &mod) {
+    LuaVar sourcedb, info, closure;
+    LuaExtStack LS(lua_state_, sourcedb, info, closure);
+    LS.rawget(sourcedb, LuaRegistry, "sourcedb");
+    LS.rawget(info, sourcedb, mod);
+    if (!LS.istable(info)) {
+        return util::ss("No such module: ", mod);
+    }
+    LS.rawget(closure, info, "loadresult");
+    if (!LS.isfunction(closure)) {
+        return util::ss(mod, ":", LS.ckstring(closure));
+    }
+    lua_pushvalue(lua_state_, closure.index());
+    return traceback_pcall(lua_state_, 0, 0);
+}
+
+eng::string SourceDB::rebuild() {
     source_clear_globals(lua_state_);
     source_load_cfunctions(lua_state_);
     source_load_cconstants(lua_state_);
+
+    eng::ostringstream errors;
+
+    for (const eng::string &mod: modules()) {
+        eng::string err = rebuild_module(mod);
+        if (!err.empty()) errors << err << std::endl;
+    }
+
+    rebuild_funcnames();
+    return errors.str();
 }
 
-eng::string SourceDB::rebuild_module(const eng::string &mod) {
-    if (mod == "CORE") {
-        rebuild_core();
-        return "";
-    } else {
-        LuaVar sourcedb, info, closure;
-        LuaExtStack LS(lua_state_, sourcedb, info, closure);
-        LS.rawget(sourcedb, LuaRegistry, "sourcedb");
-        if (!LS.istable(sourcedb)) {
-            return "SourceDB not initialized";
-        }
-        LS.rawget(info, sourcedb, mod);
-        if (!LS.istable(info)) {
-            return util::ss("No such module: ", mod);
-        }
-        LS.rawget(closure, info, "loadresult");
-        if (!LS.isfunction(closure)) {
-            return util::ss(mod, ":", LS.ckstring(closure));
-        }
-        lua_pushvalue(lua_state_, closure.index());
-        return traceback_pcall(lua_state_, 0, 0);
-    }
-}
 
 void SourceDB::init(lua_State *L) {
     register_lua_builtins();
@@ -482,8 +494,7 @@ void SourceDB::init(lua_State *L) {
     LS.set(nullstring, "");
     LS.setmetatable(nullstring, classtab);
 
-    // Rebuild the global environment.
+    rebuild();
-    rebuild_core();
     
     // We need to register all C functions with the eris permanents tables.
     LS.rawget(persist, LuaRegistry, "persist");
@@ -516,15 +527,22 @@ void SourceDB::serialize_source(const util::LuaSourceVec &sv, StreamBuffer *sb)
     }
 }
 
-void SourceDB::deserialize_source(util::LuaSourceVec *sv, StreamBuffer *sb) {
+util::LuaSourceVec SourceDB::deserialize_source(std::string_view datapack) {
-    sv->clear();
+    StreamBuffer sb(datapack);
-    int count = sb->read_int32();
+    util::LuaSourceVec sv;
-    if ((count < 0) || (count > 10000)) throw StreamCorruption();
+    try {
-    for (int i = 0; i < count; i++) {
+        sv.clear();
-        eng::string fn = sb->read_string();
+        int count = sb.read_int32();
-        eng::string code = sb->read_string();
+        if ((count < 0) || (count > 10000)) throw StreamCorruption();
-        sv->emplace_back(fn, code);
+        for (int i = 0; i < count; i++) {
+            eng::string fn = sb.read_string();
+            eng::string code = sb.read_string();
+            sv.emplace_back(fn, code);
+        }
+    } catch (const StreamException &ex) {
+        sv.clear();
     }
+    return sv;
 }
 
 // Register lua builtins.
@@ -630,7 +648,6 @@ bool SourceDB::search_docs(const eng::string &substring, std::ostream &ostream)
 
     // Search the lua source code.
     for (const eng::string &module : modules()) {
-        if (module == "CORE") continue;
         eng::string code = get_source(module);
         if (code.empty()) continue;
         util::StringVec lines = util::split_lines(code);

luprex/cpp/core/source.hpp

@@ -132,58 +132,31 @@ private:
 public:
     void init(lua_State *L);
     
-    // Update
+    // modules()
     // 
-    // Update the database using the specified lua source code.
+    // Returns a list of all the lua modules, in the proper order.
-    // Compiles these files using lua's "load" function.
-    //
-    void update(const util::LuaSourceVec &source);
-
-    // modules
-    //
-    // Returns a list of all the modules.  The first item in the list
-    // is always the string "CORE" which represents the lua core
-    // functionality with all the builtins.  This is then followed by
-    // all the lua sourcefiles in the correct order.
     //
     eng::vector<eng::string> modules();
-    
+    // Update
-    // get_source
     //
-    // Get the source code for a given module.
+    // Try to compile and load the specified source.  Then, rebuild the
+    // global environment.
     // 
-    eng::string get_source(const eng::string &fn);
+    // If this generates any errors, puts back the old code, and rebuilds
-
+    // the global environment using the old code.
-    // rebuild_module
     // 
-    // To rebuild the lua environment, fetch the module list, then
+    // Returns any error messages.  If this returns empty string, it means
-    // call rebuild_module on each module in turn.  This will return
+    // there were no errors and the code was successfully update.  If there
-    // an error message for the module, or empty string if no error.
+    // are any error messages, it means we restored the old code as best as
+    // possible.
     //
-    // This is a thin wrapper around traceback_pcall.  The return
+    eng::string update(const util::LuaSourceVec &source);
-    // value is the return value of traceback_pcall.
-    //
-    eng::string rebuild_module(const eng::string &mod);
-    
-    // rebuild_core
-    //
-    // This is equivalent to rebuild_module("CORE").  Clears the environment
-    // and installs all the builtins.  No error conditions.
-    //
-    void rebuild_core();
-
-    // rebuild_funcnames
-    //
-    // Traverses the global environment and populates the registry "funcnames"
-    // table, mapping each closure to its name.
-    //
-    void rebuild_funcnames();
 
     // Difference transmission.
     //
     // Note: The patch routine applies the differences to the source
     // database, and if there are any changes, it does a source rebuild.
-    // The patch routine returns true if anything was modified.
+    //
     //
     void diff(const SourceDB &auth, StreamBuffer *sb);
     bool patch(StreamBuffer *sb, DebugCollector *dbc);
@@ -213,7 +186,54 @@ public:
     // Serialize and unserialize a source vector.
     //
     static void serialize_source(const util::LuaSourceVec &sv, StreamBuffer *sb);
-    static void deserialize_source(util::LuaSourceVec *sv, StreamBuffer *sb);
+    static util::LuaSourceVec deserialize_source(std::string_view datapack);
+
+private:
+    //////////////////////////////////////////////////////////////////////////
+    //
+    // Internal implementation stuff.
+    //
+    //////////////////////////////////////////////////////////////////////////
+    
+    // rebuild
+    //
+    // Rebuild the global environment from the sourcedb:
+    // 
+    // * Clears the environment
+    // * Installs the builtins
+    // * Executes all the closures in the sourcedb.
+    // * Regenerates the function-names table.
+    //
+    // The closures may generate errors, if so, this returns the error
+    // messages.  Note that if there are errors, there is no automatic cleanup.
+    //
+    eng::string rebuild();
+
+    // get_source
+    //
+    // Get the source code for a given module.
+    // 
+    eng::string get_source(const eng::string &fn);
+
+    // rebuild_module
+    //
+    // To rebuild the lua environment, fetch the module list, then
+    // call rebuild_module on each module in turn.  This will return
+    // an error message for the module, or empty string if no error.
+    //
+    // This is a thin wrapper around traceback_pcall.  The return
+    // value is the return value of traceback_pcall.
+    //
+    eng::string rebuild_module(const eng::string &mod);
+    
+
+    // rebuild_funcnames
+    //
+    // Traverses the global environment and populates the registry "funcnames"
+    // table, mapping each closure to its name.
+    //
+    void rebuild_funcnames();
+
 };
 
 

luprex/cpp/core/unit-testing.cpp

@@ -55,7 +55,8 @@ public:
     virtual void event_access(AccessKind kind, int64_t place_id, std::string_view datapk, StreamBuffer *retpk) override {
         switch (kind) {
             case AccessKind::INVOKE_LUA_SOURCE: {
-                world_->update_source(datapk, 0);
+                Invocation inv(kind, place_id, place_id, datapk);
+                world_->invoke(0, inv);
                 run_unittests(world_->state());
                 stop_driver();
                 break;

luprex/cpp/core/world-core.cpp

@@ -572,71 +572,6 @@ void World::probe_lua_call(int64_t actor_id, int64_t place_id, std::string_view
     clear_lthread_state();
 }
 
-
-// This is called from World::update_source, and also
-// from World::patch_source in the difference transmitter.
-//
-// When called from the difference transmitter, we suppress
-// error messages.
-//
-// For the moment, errors are channeled to util::dprint,
-// and 'print' statements just go to std::cerr.  Neither
-// of these is ideal.  We need to get serious about setting
-// up error handling.
-//
-// We also need to figure out a solution for what happens if
-// some lua source file tries to modify, say, tangible state
-// in top-level code.
-//
-bool World::rebuild_sourcedb(int64_t actor_id) {
-    int successes = 0;
-    int failures = 0;
-    for (const eng::string &mod: source_db_.modules()) {
-        open_lthread_state(0, 0, 0, false);
-        eng::string err = source_db_.rebuild_module(mod);
-        eng::string prints = lthread_prints_.str();
-        clear_lthread_state();
-        if (err.empty()) successes ++;
-        else failures ++;
-        if ((!err.empty()) || (!prints.empty())) {
-            lthread_prints_ << "Compiling " << mod << ":" << std::endl;
-            if (!err.empty()) lthread_prints_ << err << std::endl;
-            if (!prints.empty()) lthread_prints_ << prints;
-            util::dprintview(lthread_prints_.view());
-            if (actor_id != 0) lthread_prints_to_actor(actor_id);
-        }
-    }
-    source_db_.rebuild_funcnames();
-    lthread_prints_ << "Compiled " << successes << " modules successfully." << std::endl;
-    if (failures > 0) {
-        lthread_prints_ << "Compiled " << failures << " modules with errors." << std::endl;
-    }
-    util::dprintview(lthread_prints_.view());
-    if (actor_id > 0) lthread_prints_to_actor(actor_id);
-    return (failures == 0);
-}
-
-bool World::update_source(const util::LuaSourceVec &source, int64_t actor_id) {
-    assert(stack_is_clear());
-    source_db_.update(source);
-    return rebuild_sourcedb(actor_id);
-    assert(stack_is_clear());
-}
-
-bool World::update_source(std::string_view sourcepack, int64_t actor_id) {
-    if (sourcepack.empty()) {
-        return false;
-    }
-    try {
-        StreamBuffer sb(sourcepack);
-        util::LuaSourceVec sv;
-        SourceDB::deserialize_source(&sv, &sb);
-        return update_source(sv, actor_id);
-    } catch (const StreamException &ex) {
-        return false;
-    }
-}
-
 void World::http_response(const HttpParser &response) {
     // Find the request.
     auto iter = http_requests_.find(response.request_id());
@@ -1019,14 +954,27 @@ void World::invoke_lua_source(int64_t actor_id, int64_t place_id, std::string_vi
     if (actor_id != place_id) return;
 
     // Check if this is the first time we're loading the source.
-    bool brand_new = (source_db_.modules().size() == 1);
+    bool brand_new = (source_db_.modules().size() == 0);
 
-    // Compile and load the source.
+    // Deserialize the datapack.
-    bool success = update_source(datapack, actor_id);
+    util::LuaSourceVec sv = SourceDB::deserialize_source(datapack);
+    if (sv.empty()) return;
+
+    // Try to compile the code.
+    open_lthread_state(actor_id, actor_id, 0, false);
+    eng::string errors = source_db_.update(sv);
+
+    if (errors.empty()) {
+        lthread_prints_ << "Compiled source successfully.\n";
+    } else {
+        lthread_prints_ << "Compiling source: \n" << errors;
+    }
+    util::dprint(lthread_prints_.view());
+    lthread_prints_to_actor(actor_id);
 
     // Call world.init
     if (brand_new) {
-        if (success) {
+        if (errors.empty()) {
             {
                 lua_State *L = state();
                 LuaVar lclass, lfunc;

luprex/cpp/core/world-diffxmit.cpp

@@ -290,11 +290,7 @@ void World::diff_tanclass(int64_t actor_id, World *master, StreamBuffer *xsb) {
 
 void World::patch_source(StreamBuffer *sb, DebugCollector *dbc) {
     DebugBlock dbb(dbc, "patch_source");
-    bool modified = source_db_.patch(sb, dbc);
+    source_db_.patch(sb, dbc);
-    if (modified) {
-        rebuild_sourcedb(0);
-        DebugLine(dbc) << "Source DB rebuilt";
-    }
 }
 
 void World::diff_source(World *master, StreamBuffer *sb) {
@@ -359,6 +355,7 @@ void World::diff_globals(World *master, StreamBuffer *sb) {
 
 int64_t World::patch(StreamBuffer *sb, DebugCollector *dbc) {
     DebugBlock dbb(dbc, "patch");
+    clear_lthread_state();
     int64_t actor_id = patch_actor(sb, dbc);
     patch_visible(sb, dbc);
     bool full = sb->read_bool();

luprex/cpp/core/world.hpp

@@ -242,23 +242,6 @@ public:
     //
     SourceDB &get_source() { return source_db_; }
 
-    // Rebuild the global environment from the source database.
-    //
-    // Error messages go to the specified actor, and also dprint.
-    //
-    // Returns true if the rebuild goes without errors.
-    //
-    bool rebuild_sourcedb(int64_t actor_id);
-    
-    // Update the source database from disk, then rebuild the global environment.
-    //
-    // Error messages go to the specified actor, and also dprint.
-    //
-    // Returns true if the update goes without errors.
-    //
-    bool update_source(const util::LuaSourceVec &source, int64_t actor_id);
-    bool update_source(std::string_view sourcepk, int64_t actor_id);
-    
     // Supply an HTTP response to an outstanding HTTP request.
     //
     void http_response(const HttpParser &response);

luprex/lua/login.lua

@@ -54,7 +54,6 @@ function sphere.lookhotkeys(add)
     add("FaceR", "Sphere Yo", function () dprint("Doing Sphere Yo") end)
 end
 
-
 function probe.getlookat()
     local class = tangible.getclass(place)