Function lookforfunc

src/Chain/libraries/glua/loadlib.cpp:338–356

** Look for a C function named 'sym' in a dynamically loaded library ** 'path'. ** First, check whether the library is already loaded; if not, try ** to load it. ** Then, if 'sym' is '*', return true (as library has been loaded). ** Otherwise, look for symbol 'sym' in the library and push a ** C function with that symbol. ** Return 0 and 'true' or a function in the stack; in case of ** errors, ret

** errors, return an error code and an error message in the stack.
*/
static int lookforfunc(lua_State *L, const char *path, const char *sym) {
    void *reg = checkclib(L, path);  /* check loaded C libraries */
    if (reg == nullptr) {  /* must load library? */
        reg = lsys_load(L, path, *sym == '*');  /* global symbols if 'sym'=='*' */
        if (reg == nullptr) return ERRLIB;  /* unable to load library */
        addtoclib(L, path, reg);
    }
    if (*sym == '*') {  /* loading only library (no function)? */
        lua_pushboolean(L, 1);  /* return 'true' */
        return 0;  /* no errors */
    }
    else {
        lua_CFunction f = lsys_sym(L, reg, sym);
        if (f == nullptr)
            return ERRFUNC;  /* unable to find function */
        lua_pushcfunction(L, f);  /* else create new function */
        return 0;  /* no errors */
    }
}


static int ll_loadlib(lua_State *L) {