用memmove函数代替strncpy函数

/**51Testing软件测试网Vl0w(|r
 * strncpy - Copy a length-limited, %NUL-terminated string51Testing软件测试网5|V O'Mvk'@3g
 * @dest: Where to copy the string to
#gS+^(Ru1{U2U0 * @src: Where to copy the string from
c:i!Rg&z{0 * @count: The maximum number of bytes to copy
&h9F&?I4L2lYr0 *
4czL&{P0 * The result is not %NUL-terminated if the source exceeds51Testing软件测试网b!t.WG)ve
 * @count bytes.
4d T-R,c"F!u0 */
k"N"} A?(scG@^0char * strncpy(char * dest,const char *src,size_t count)51Testing软件测试网 t,cn:~:to1h
{51Testing软件测试网vP:Xi,{1f q
 char *tmp = dest;51Testing软件测试网%dta&?zC

 while (count) {
C:p~P Qvx0  if ((*tmp = *src) != 0) src++;51Testing软件测试网 vTcv k gj
  tmp++;51Testing软件测试网@'v$E@2O
  count--;
} A rKP};dg#v0 }

b:\!zR,caDj0 return dest;51Testing软件测试网LE!^Q z3{
}

nd$Jv9a0/**51Testing软件测试网 I'yXK#ok
 * memmove - Copy one area of memory to another51Testing软件测试网8i Wc"n3|:CM]hu
 * @dest: Where to copy to51Testing软件测试网b0g'QhW
 * @src: Where to copy from51Testing软件测试网7w/L)\5Bf^&x
 * @count: The size of the area.51Testing软件测试网4O9n;i*[{9i,Yu(I
 *51Testing软件测试网C sD*Tbfoi'mm~1v\
 * Unlike memcpy(), memmove() copes with overlapping areas.51Testing软件测试网{m5c9HOL"pX
 */51Testing软件测试网G1}1}x*I
void * memmove(void * dest,const void *src,size_t count)51Testing软件测试网.f L0?9`T
{
%ODpYAT*B m)JL0 char *tmp, *s;

 if (dest <= src) {
]|4w;hR2}x0  tmp = (char *) dest;51Testing软件测试网 d,? q(US`IZ
  s = (char *) src;51Testing软件测试网7D1|i D q
  while (count--)51Testing软件测试网/Z9B!T!r#ZwKB$pc,o
   *tmp++ = *s++;51Testing软件测试网E/Yg%`5s!l
  }
7o~,Z)s cU&X,j!v0 else {51Testing软件测试网1{ n(N9AqS
  tmp = (char *) dest + count;51Testing软件测试网c%_/T(t"f;R$f
  s = (char *) src + count;

~*sm4x.yM6l'z0  while (count--)51Testing软件测试网|?&b;M_3_%Z)d7i
   *--tmp = *--s;51Testing软件测试网"j-dD&w%{
  }

 return dest;
dbK+X'Pq$^0}