static int luaB_pcall (lua_State *L) {
int status;
luaL_checkany(L, 1);
lua_pushnil(L);
lua_insert(L, 1); /* create space for status result */
status = lua_pcallk(L, lua_gettop(L) - 2, LUA_MULTRET, 0, 0, pcallcont);
return finishpcall(L, (status == LUA_OK));
}
static int luaB_pcall (lua_State *L) {
int status;
luaL_checkany(L, 1);
lua_pushboolean(L, 1); /* first result if no errors */
lua_insert(L, 1); /* put it in place */
status = lua_pcallk(L, lua_gettop(L) - 2, LUA_MULTRET, 0, 0, finishpcall);
return finishpcall(L, status, 0);
}
static int luaB_xpcall (lua_State *L) {
int status;
int n = lua_gettop(L);
luaL_argcheck(L, n >= 2, 2, "value expected");
lua_pushvalue(L, 1); /* exchange function... */
lua_copy(L, 2, 1); /* ...and error handler */
lua_replace(L, 2);
status = lua_pcallk(L, n - 2, LUA_MULTRET, 1, 0, pcallcont);
return finishpcall(L, (status == LUA_OK));
}
/*
** Do a protected call with error handling. After 'lua_rotate', the
** stack will have <f, err, true, f, [args...]>; so, the function passes
** 2 to 'finishpcall' to skip the 2 first values when returning results.
*/
static int luaB_xpcall (lua_State *L) {
int status;
int n = lua_gettop(L);
luaL_checktype(L, 2, LUA_TFUNCTION); /* check error function */
lua_pushboolean(L, 1); /* first result */
lua_pushvalue(L, 1); /* function */
lua_rotate(L, 3, 2); /* move them below function's arguments */
status = lua_pcallk(L, n - 2, LUA_MULTRET, 2, 2, finishpcall);
return finishpcall(L, status, 2);
}
static int pcallcont (lua_State *L) {
int status = lua_getctx(L, NULL);
return finishpcall(L, (status == LUA_YIELD));
}
