require("mylib") // load mylib.efi or mylib.so or mylib.dll
本篇學習如何建立在Uefi 下可供Lua載入的library
試圖讓library能由Lua C Loader 載入
關鍵檔案在src/loadlib.c
LUA_USE_DLOPEN :for linux *.so
LUA_DL_DLL :for windows *.dll
/*
119 ** {========================================================================
120 ** This is an implementation of loadlib based on the dlfcn interface.
121 ** The dlfcn interface is available in Linux, SunOS, Solaris, IRIX, FreeBSD,
122 ** NetBSD, AIX 4.2, HPUX 11, and probably most other Unix flavors, at least
123 ** as an emulation layer on top of native functions.
124 ** =========================================================================
125 */
126
127 #include <dlfcn.h>
128
129 static void ll_unloadlib (void *lib) {
130 dlclose(lib);
131 }
132
133
134 static void *ll_load (lua_State *L, const char *path, int seeglb) {
135 void *lib = dlopen(path, RTLD_NOW | (seeglb ? RTLD_GLOBAL : RTLD_LOCAL));
136 if (lib == NULL) lua_pushstring(L, dlerror());
137 return lib;
138 }
139
140
141 static lua_CFunction ll_sym (lua_State *L, void *lib, const char *sym) {
142 lua_CFunction f = (lua_CFunction)dlsym(lib, sym);
143 if (f == NULL) lua_pushstring(L, dlerror());
144 return f;
145 }
146
147 /* }====================================================== */
148
149
222 #undef LIB_FAIL
223 #define LIB_FAIL "absent"
224
225
226 #define DLMSG "dynamic libraries not enabled; check your Lua installation"
227
228
229 static void ll_unloadlib (void *lib) {
230 (void)(lib); /* not used */
231 }
232
233
234 static void *ll_load (lua_State *L, const char *path, int seeglb) {
235 (void)(path); (void)(seeglb); /* not used */
236 lua_pushliteral(L, DLMSG);
237 return NULL;
238 }
239
240
241 static lua_CFunction ll_sym (lua_State *L, void *lib, const char *sym) {
242 (void)(lib); (void)(sym); /* not used */
243 lua_pushliteral(L, DLMSG);
244 return NULL;
245 }
初步判斷整個過程是利用dlopen 及 LoadLibraryEx的加載過程.......
疑問: Uefi 有Dynamic Load Library架構嗎?好像是沒有,載入Library有重定位問題,UEFI 可由載入的Application or Driver 中,對應出所要的Function ?要將Library以UEFI Driver 常駐形式存在,且初始化時,要建立FunctionName及FunctionAddress 對應關係
static void ll_unloadlib (void *lib)
static void *ll_load (lua_State *L, const char *path, int seeglb)
static lua_CFunction ll_sym (lua_State *L, void *lib, const char *sym)
在UEFI 下實現構想如下:
1.建立 EFI_LUA_DLL_PROTOCOL,用於Function name查找
2.於ll_load時載入 Lua Module Uefi Driver
3.於ll_unloadlib時卸載 Lua Module Uefi Driver
4.於ll_sym時call method 取得Function Address
static int ll_loadfunc (lua_State *L, const char *path, const char *sym) {
287 void *reg = ll_checkclib(L, path); /* check loaded C libraries */
288 if (reg == NULL) { /* must load library? */
289 reg = ll_load(L, path, *sym == '*');
290 if (reg == NULL) return ERRLIB; /* unable to load library */
291 ll_addtoclib(L, path, reg);
292 }
293 if (*sym == '*') { /* loading only library (no function)? */
294 lua_pushboolean(L, 1); /* return 'true' */
295 return 0; /* no errors */
296 }
297 else {
298 lua_CFunction f = ll_sym(L, reg, sym);
299 if (f == NULL)
300 return ERRFUNC; /* unable to find function */
301 lua_pushcfunction(L, f); /* else create new function */
302 return 0; /* no errors */
303 }
304 }
print(package.path)
require("hello")
(收工)
