common.h

计算任意字符串MD5散列值的程序

#define wipememory2(_ptr,_set,_len) do { volatile char *_vptr=(volatile char *)(_ptr); size_t _vlen=(_len); while(_vlen) { *_vptr=(_set); _vptr++; _vlen--; } } while(0)
#define wipememory(_ptr,_len) wipememory2(_ptr,0,_len)

/****************
 * Rotate a 32 bit integer by n bytes
 */
#if defined(__GNUC__) && defined(__i386__)
static inline u32
rol( u32 x, int n)
{
	__asm__("roll %%cl,%0"
		:"=r" (x)
		:"0" (x),"c" (n));
	return x;
}
#else
#define rol(x,n) ( ((x) << (n)) | ((x) >> (32-(n))) )
#endif

#define DIM(v) (sizeof(v)/sizeof((v)[0]))