#4 A problem about dllist

[Fei]

I found a problem when using SGLIB_DL_LIST_ADD, the order of the element is not the reverse order I added them, so I changed SGLIB_DL_LIST_ADD_BEFORE, now it is as follow. And I can use SGLIB_DL_LIST_REVERSE to make the elements in the order I added them, do you think it is right? Thanks.

#define SGLIB_DL_LIST_ADD_BEFORE(type, place, elem, previous, next) {\ if ((place) == NULL) {\ SGLIB___DL_LIST_CREATE_SINGLETON(type, place, elem, previous, next);\ } else {\ (elem)->next = (place);\ (elem)->previous = (place)->previous;\ (place)->previous = (elem);\ if ((elem)->previous != NULL) (elem)->previous->next = (elem);\ (place) = (elem);\ }\ }