Simple codegen for lua c library static inclusion (#178)

Author: Trey2k

SConstruct

@@ -9,9 +9,14 @@ env.tools=['mingw']
 env.Append(CPPDEFINES = ['LAPI_GDEXTENSION'])
 env.Append(CPPPATH 	  = [Dir('src').abspath, Dir('external').abspath])
 
+env['sources'] = []
+Export('env')
+SConscript("lua_libraries/SConscript")
+
 sources = Glob('*.cpp')
 sources.append(Glob('src/*.cpp'))
 sources.append(Glob('src/classes/*.cpp'))
+sources.append(env['sources'])
 
 if env["luaapi_luaver"] == 'jit':
     env.Append(CPPDEFINES=['LAPI_LUAJIT'])

SCsub

@@ -18,6 +18,7 @@ if env["luaapi_luaver"] == "jit" and env['platform']=='javascript':
 
 Export('env_lua')
 SConscript('external/SCsub')
+SConscript('lua_libraries/SCsub')
 
 if env["luaapi_luaver"] == 'jit':
     env_lua.Append(CPPDEFINES=['LAPI_LUAJIT'])

doc_classes/LuaAPI.xml

@@ -22,10 +22,11 @@
 			</description>
 		</method>
 		<method name="bind_libraries">
-			<return type="void" />
+			<return type="LuaError" />
 			<param index="0" name="Array" type="Array" />
 			<description>
 				Bind lua libraries to the LuaAPI Object. 
+				Returns an error if a library fails to bind.
 				Note: in C#, the param Array must be a [code]Godot.Collections.Array[/code] and not a [code]System.Array[/code] class.
 			</description>
 		</method>

external/SCsub

@@ -1,4 +1,3 @@
-
 Import('env')
 Import('env_lua')
 
@@ -74,6 +73,7 @@ if luaver == "jit":
     else:
         env.Append(LIBPATH=[Dir("luaJIT/src").abspath])
         env.Append(LIBS=['libluajit'])
+    env_lua.Append(CPPPATH=[Dir('luaJIT/src').abspath])
 
 elif luaver == "5.1":
     env_lua.Append(CPPDEFINES='MAKE_LIB')
@@ -87,7 +87,8 @@ elif luaver == "5.1":
         env_lua['CFLAGS'].remove('-std=gnu11')
         env_lua.Append(CFLAGS=['-std=c99'])
 
-    env_lua.add_source_files(env.modules_sources,'lua/*.c')
+    env_lua.Append(CPPPATH=[Dir('lua51').abspath])
+    env_lua.add_source_files(env.modules_sources,'lua51/*.c')
 
 else:
     env_lua.Append(CPPDEFINES='MAKE_LIB')
@@ -101,5 +102,6 @@ else:
         env_lua['CFLAGS'].remove('-std=gnu11')
         env_lua.Append(CFLAGS=['-std=c99'])
 
-    env_lua.add_source_files(env.modules_sources,'lua/onelua.c')
+    env_lua.Append(CPPPATH=[Dir('lua').abspath])
+    env_lua.add_source_files(env.modules_sources, 'lua/onelua.c')
 

lua_libraries/.gitignore

@@ -0,0 +1,9 @@
+*
+
+!.gitignore
+!SCsub
+!SConscript
+!codegen.py
+!codegen.py
+!README.md
+!lua_libraries.h

lua_libraries/README.md

@@ -0,0 +1,8 @@
+## Lua Libraries
+This is a code gen module which allows you to statically compile a lua C library into this addon. Its as simple as downloading the source for the addon, and adding it as a folder with the library name in this folder.
+
+It is important that the folder name be exactly the library name in lowercase. No version numbers included.
+
+The code gen will auto detect it next time you build the addon. Either as a module or for GDExtension.
+
+This is very new and potentially very prone to failure. So for lpeg has been tested and confirmed to work.

lua_libraries/SConscript

@@ -0,0 +1,10 @@
+Import('env')
+from codegen import code_gen
+
+code_gen(env['luaapi_luaver'] == 'jit')
+
+sources = ['lua_libraries.gen.cpp']
+library_name = "liblualibraries{}{}".format(env['suffix'], env["LIBSUFFIX"])
+
+env.Append(sources=["lua_libraries/lua_libraries.gen.cpp"])
+env.Append(CPPPATH=[Dir('.').abspath])

lua_libraries/SCsub

@@ -0,0 +1,9 @@
+Import('env')
+Import('env_lua')
+
+from codegen import code_gen
+
+code_gen(env['luaapi_luaver'] == 'jit')
+
+env_lua.add_source_files(env.modules_sources, "lua_libraries.gen.cpp")
+env_lua.Append(CPPPATH=[Dir('.').abspath])

lua_libraries/codegen.py

@@ -0,0 +1,95 @@
+import os
+
+def code_gen(luaJIT=False):
+    lua_libraries = [
+        "base",
+        "coroutine",
+        "debug",
+        "io",
+        "math",
+        "os",
+        "package",
+        "string",
+        "table",
+        "utf8"
+    ]
+
+    luajit_libraries = [
+        "base",
+        "bit",
+        "debug",
+        "ffi",
+        "io",
+        "jit",
+        "math",
+        "os",
+        "package",
+        "string",
+        "string_buffer",
+        "table"
+    ]
+
+    libraries = lua_libraries
+    lib_source_files = []
+
+    if luaJIT:
+        libraries = luajit_libraries
+
+    for library in os.listdir("./"):
+        if not os.path.isdir(library) or library == "__pycache__" or library == "bin":
+            continue
+        
+        libraries.append(library)
+
+        for source_file in os.listdir("./%s" % library):
+            if source_file.endswith(".cpp") or source_file.endswith(".c"):
+                lib_source_files.append(os.path.join(library, source_file))
+
+    luaLibraries_gen_cpp = "#include \"lua_libraries.h\"\n#include <map>\n#include <string>\n\n"
+    
+    if len(lib_source_files) > 0:
+        for source_file in lib_source_files:
+            luaLibraries_gen_cpp += "#include \"%s\"\n" % source_file
+        luaLibraries_gen_cpp += "\n"
+    
+    luaLibraries_gen_cpp += "std::map<std::string, lua_CFunction> luaLibraries = {\n"
+
+    for library in libraries:
+        luaLibraries_gen_cpp += "\t{ \"%s\", luaopen_%s },\n" % (library, library)
+
+    luaLibraries_gen_cpp += "};\n"
+    if luaJIT:
+        luaLibraries_gen_cpp += """
+bool loadLuaLibrary(lua_State *L, String libraryName) {
+	const char *lib_c_str = libraryName.ascii().get_data();
+	if (luaLibraries[lib_c_str] == nullptr) {
+		return false;
+	}
+	
+    lua_pushcfunction(L, luaLibraries[lib_c_str]);
+    if (libraryName == "base") {
+        lua_pushstring(L, "");
+    } else {
+	    lua_pushstring(L, lib_c_str);
+    }
+	lua_call(L, 1, 0);
+	return true;
+}
+"""
+    else:
+        luaLibraries_gen_cpp += """
+bool loadLuaLibrary(lua_State *L, String libraryName) {
+	const char *lib_c_str = libraryName.ascii().get_data();
+	if (luaLibraries[lib_c_str] == nullptr) {
+		return false;
+	}
+
+	luaL_requiref(L, lib_c_str, luaLibraries[lib_c_str], 1);
+	lua_pop(L, 1);
+	return true;
+}
+"""
+
+    gen_file = open("lua_libraries.gen.cpp", "w")
+    gen_file.write(luaLibraries_gen_cpp)
+    gen_file.close()

lua_libraries/lua_libraries.h

@@ -0,0 +1,18 @@
+#ifndef LUA_LIBRARIES_H
+#define LUA_LIBRARIES_H
+
+#include <lua/lua.hpp>
+
+#ifndef LAPI_GDEXTENSION
+#include "core/string/ustring.h"
+
+#include "core/variant/variant.h"
+#else
+#include <godot_cpp/variant/string.hpp>
+
+using namespace godot;
+#endif
+
+bool loadLuaLibrary(lua_State *L, String libraryName);
+
+#endif