用#define来代替计算

freeRDP中利用宏来计算。

#define Stream_Read_UINT64(_s, _v) do { _v = \

(UINT64)(*_s->pointer) + \
(((UINT64)(*(_s->pointer + 1))) << 8) + \
(((UINT64)(*(_s->pointer + 2))) << 16) + \
(((UINT64)(*(_s->pointer + 3))) << 24) + \
(((UINT64)(*(_s->pointer + 4))) << 32) + \
(((UINT64)(*(_s->pointer + 5))) << 40) + \
(((UINT64)(*(_s->pointer + 6))) << 48) + \
(((UINT64)(*(_s->pointer + 7))) << 56); \
_s->pointer += 8; } while (0)