1 files changed, 233 insertions, 0 deletions
diff --git a/src/common/impl/lua.c b/src/common/impl/lua.c
new file mode 100644
index 0000000..ffc1d83
--- /dev/null
+++ b/src/common/impl/lua.c
@@ -0,0 +1,233 @@
+#if FF_HAVE_LUA
+
+    #include "common/lua.h"
+    #include "common/mallocHelper.h"
+
+struct FFLuaData luaData;
+
+static yyjson_mut_val* lua2yyjson(lua_State* L, int idx, yyjson_mut_doc* doc, int depth) {
+    if (__builtin_expect(depth > 15, false)) {
+        yyjson_mut_doc_free(doc);
+        lua_pushlstring(
+            L, "yyjson: recursion depth exceeded; possible circular reference", strlen("yyjson: recursion depth exceeded; possible circular reference"));
+        lua_error(L); // noreturn
+        __builtin_unreachable();
+    }
+
+    if (idx < 0) {
+        idx = lua_gettop(L) + idx + 1;
+    }
+    int type = lua_type(L, idx);
+
+    switch (type) {
+        case LUA_TNIL:
+            return yyjson_mut_null(doc);
+
+        case LUA_TBOOLEAN:
+            return yyjson_mut_bool(doc, lua_toboolean(L, idx));
+
+        case LUA_TNUMBER: {
+            if (lua_isinteger(L, idx)) {
+                lua_Integer i = lua_tointeger(L, idx);
+                return yyjson_mut_sint(doc, (int64_t) i);
+            } else {
+                return yyjson_mut_real(doc, lua_tonumber(L, idx));
+            }
+        }
+
+        case LUA_TSTRING: {
+            size_t len;
+            const char* str = lua_tolstring(L, idx, &len);
+            return yyjson_mut_strncpy(doc, str, len);
+        }
+
+        case LUA_TTABLE: {
+            lua_Unsigned len = lua_rawlen(L, idx);
+            int is_array = 1;
+
+            if (len == 0) {
+                lua_pushnil(L);
+                is_array = 0;
+                if (lua_next(L, idx) != 0) {
+                    lua_pop(L, 2);
+                }
+            } else {
+                lua_pushnil(L);
+                while (lua_next(L, idx) != 0) {
+                    if (lua_type(L, -2) != LUA_TNUMBER) {
+                        is_array = 0;
+                        lua_pop(L, 2);
+                        break;
+                    }
+                    int isnum = false;
+                    lua_Integer k = lua_tointegerx(L, -2, &isnum);
+                    if (!isnum || (lua_Unsigned) k > len) {
+                        is_array = 0;
+                        lua_pop(L, 2);
+                        break;
+                    }
+                    lua_pop(L, 1);
+                }
+            }
+
+            if (is_array) {
+                yyjson_mut_val* arr = yyjson_mut_arr(doc);
+                for (lua_Unsigned i = 1; i <= len; i++) {
+                    lua_rawgeti(L, idx, (lua_Integer) i);
+                    yyjson_mut_val* val = lua2yyjson(L, -1, doc, depth + 1);
+                    yyjson_mut_arr_append(arr, val);
+                    lua_pop(L, 1);
+                }
+                return arr;
+            } else {
+                yyjson_mut_val* obj = yyjson_mut_obj(doc);
+                lua_pushnil(L);
+                while (lua_next(L, idx) != 0) {
+                    size_t klen;
+                    const char* key_str = luaL_tolstring(L, -2, &klen);
+                    yyjson_mut_val* key = yyjson_mut_strncpy(doc, key_str, klen);
+                    lua_pop(L, 1);
+
+                    yyjson_mut_val* val = lua2yyjson(L, -1, doc, depth + 1);
+                    yyjson_mut_obj_add(obj, key, val);
+                    lua_pop(L, 1);
+                }
+                return obj;
+            }
+        }
+
+        default:
+            return yyjson_mut_null(doc);
+    }
+}
+
+static int yyjsonEncode(lua_State* L) {
+    luaL_checkany(L, 1);
+
+    bool pretty = false;
+    if (lua_isboolean(L, 2)) {
+        pretty = (int) lua_toboolean(L, 2);
+    }
+
+    yyjson_mut_doc* doc = yyjson_mut_doc_new(NULL);
+    if (__builtin_expect(!doc, false)) {
+        lua_pushlstring(L, "yyjson: yyjson_mut_doc_new() failed", strlen("yyjson: yyjson_mut_doc_new() failed"));
+        return lua_error(L);
+    }
+
+    yyjson_mut_val* root = lua2yyjson(L, 1, doc, 0);
+    yyjson_mut_doc_set_root(doc, root);
+
+    size_t jsonLen;
+    yyjson_write_err err = {};
+    FF_AUTO_FREE const char* jsonStr = yyjson_mut_write_opts(doc, YYJSON_WRITE_ALLOW_INF_AND_NAN | (pretty ? YYJSON_WRITE_PRETTY_TWO_SPACES : 0), NULL, &jsonLen, &err);
+
+    if (__builtin_expect(jsonStr != NULL, true)) {
+        lua_pushlstring(L, jsonStr, jsonLen);
+        yyjson_mut_doc_free(doc);
+        return 1;
+    } else {
+        yyjson_mut_doc_free(doc);
+        {
+            FF_STRBUF_AUTO_DESTROY errBuf = ffStrbufCreateStatic("yyjson: yyjson_mut_write_opts() failed: ");
+            ffStrbufAppendS(&errBuf, err.msg);
+            lua_pushlstring(L, errBuf.chars, errBuf.length);
+        }
+
+        return lua_error(L); // longjmp
+    }
+}
+
+const char* ffLuaLoadState(void) {
+    if (luaData.inited) {
+        if (luaData.L == NULL) {
+            return "Lua library is not available";
+        }
+        return NULL;
+    }
+
+    luaData.inited = true;
+    // clang-format off
+    #ifdef _WIN32
+        #define FF_LOAD_LIBLUA(version) FF_LIBRARY_LOAD_MESSAGE(liblua, \
+            "lua5" #version FF_LIBRARY_EXTENSION, 0)
+    #else
+        #define FF_LOAD_LIBLUA(version) FF_LIBRARY_LOAD_MESSAGE(liblua, \
+            "liblua5." #version FF_LIBRARY_EXTENSION, 0, \
+            "liblua-5." #version FF_LIBRARY_EXTENSION, 0, \
+            "liblua5." #version FF_LIBRARY_EXTENSION ".5." #version, 0)
+    #endif
+    // clang-format on
+    #if LUA_VERSION_NUM == 505
+    FF_LOAD_LIBLUA(5)
+    #elif LUA_VERSION_NUM == 504
+    FF_LOAD_LIBLUA(4)
+    #elif LUA_VERSION_NUM == 503
+    FF_LOAD_LIBLUA(3)
+    #else
+        #error "Unsupported Lua version"
+    #endif
+    #undef FF_LOAD_LIBLUA
+    FF_LIBRARY_LOAD_SYMBOL_MESSAGE(liblua, luaL_newstate)
+    #if LUA_VERSION_NUM >= 505
+    FF_LIBRARY_LOAD_SYMBOL_MESSAGE(liblua, luaL_openselectedlibs)
+    #else
+    FF_LIBRARY_LOAD_SYMBOL_MESSAGE(liblua, luaL_requiref)
+    FF_LIBRARY_LOAD_SYMBOL_MESSAGE(liblua, luaopen_base)
+    FF_LIBRARY_LOAD_SYMBOL_MESSAGE(liblua, luaopen_math)
+    FF_LIBRARY_LOAD_SYMBOL_MESSAGE(liblua, luaopen_string)
+    FF_LIBRARY_LOAD_SYMBOL_MESSAGE(liblua, luaopen_table)
+    #endif
+
+    #if !FF_DISABLE_DLOPEN
+    FF_LIBRARY_LOAD_SYMBOL_VAR_MESSAGE(liblua, luaData, luaL_checkany)
+    FF_LIBRARY_LOAD_SYMBOL_VAR_MESSAGE(liblua, luaData, luaL_loadbufferx)
+    FF_LIBRARY_LOAD_SYMBOL_VAR_MESSAGE(liblua, luaData, luaL_tolstring)
+    FF_LIBRARY_LOAD_SYMBOL_VAR_MESSAGE(liblua, luaData, lua_callk)
+    FF_LIBRARY_LOAD_SYMBOL_VAR_MESSAGE(liblua, luaData, lua_createtable)
+    FF_LIBRARY_LOAD_SYMBOL_VAR_MESSAGE(liblua, luaData, lua_error)
+    FF_LIBRARY_LOAD_SYMBOL_VAR_MESSAGE(liblua, luaData, lua_gettop)
+    FF_LIBRARY_LOAD_SYMBOL_VAR_MESSAGE(liblua, luaData, lua_isinteger)
+    FF_LIBRARY_LOAD_SYMBOL_VAR_MESSAGE(liblua, luaData, lua_next)
+    FF_LIBRARY_LOAD_SYMBOL_VAR_MESSAGE(liblua, luaData, lua_pcallk)
+    FF_LIBRARY_LOAD_SYMBOL_VAR_MESSAGE(liblua, luaData, lua_pushboolean)
+    FF_LIBRARY_LOAD_SYMBOL_VAR_MESSAGE(liblua, luaData, lua_pushcclosure)
+    FF_LIBRARY_LOAD_SYMBOL_VAR_MESSAGE(liblua, luaData, lua_pushinteger)
+    FF_LIBRARY_LOAD_SYMBOL_VAR_MESSAGE(liblua, luaData, lua_pushlstring)
+    FF_LIBRARY_LOAD_SYMBOL_VAR_MESSAGE(liblua, luaData, lua_pushnil)
+    FF_LIBRARY_LOAD_SYMBOL_VAR_MESSAGE(liblua, luaData, lua_pushnumber)
+    FF_LIBRARY_LOAD_SYMBOL_VAR_MESSAGE(liblua, luaData, lua_pushvalue)
+    FF_LIBRARY_LOAD_SYMBOL_VAR_MESSAGE(liblua, luaData, lua_rawgeti)
+    FF_LIBRARY_LOAD_SYMBOL_VAR_MESSAGE(liblua, luaData, lua_rawlen)
+    FF_LIBRARY_LOAD_SYMBOL_VAR_MESSAGE(liblua, luaData, lua_setfield)
+    FF_LIBRARY_LOAD_SYMBOL_VAR_MESSAGE(liblua, luaData, lua_setglobal)
+    FF_LIBRARY_LOAD_SYMBOL_VAR_MESSAGE(liblua, luaData, lua_seti)
+    FF_LIBRARY_LOAD_SYMBOL_VAR_MESSAGE(liblua, luaData, lua_settop)
+    FF_LIBRARY_LOAD_SYMBOL_VAR_MESSAGE(liblua, luaData, lua_toboolean)
+    FF_LIBRARY_LOAD_SYMBOL_VAR_MESSAGE(liblua, luaData, lua_tointegerx)
+    FF_LIBRARY_LOAD_SYMBOL_VAR_MESSAGE(liblua, luaData, lua_tolstring)
+    FF_LIBRARY_LOAD_SYMBOL_VAR_MESSAGE(liblua, luaData, lua_tonumberx)
+    FF_LIBRARY_LOAD_SYMBOL_VAR_MESSAGE(liblua, luaData, lua_type)
+    #endif
+
+    lua_State* L = ffluaL_newstate();
+    if (L == NULL) {
+        return "luaL_newstate() failed";
+    }
+    #if LUA_VERSION_NUM >= 505
+    ffluaL_openselectedlibs(L, LUA_GLIBK | LUA_MATHLIBK | LUA_STRLIBK | LUA_TABLIBK, 0);
+    #else
+    ffluaL_requiref(L, LUA_GNAME, ffluaopen_base, 1);
+    ffluaL_requiref(L, LUA_MATHLIBNAME, ffluaopen_math, 1);
+    ffluaL_requiref(L, LUA_STRLIBNAME, ffluaopen_string, 1);
+    ffluaL_requiref(L, LUA_TABLIBNAME, ffluaopen_table, 1);
+    lua_settop(L, 0);
+    #endif
+    lua_pushcfunction(L, yyjsonEncode);
+    lua_setglobal(L, "json_encode");
+    luaData.L = L;
+    liblua = NULL; // don't close lua
+    return NULL;
+}
+
+#endif