(原创)随机串的产生,可以用于盐值

之前要加密密码的时候，要加入盐值以加强强度，找了部分，又在网上的基础上修改了下(参考网页:http://blog.csdn.net/wangchangshuai0010/article/details/17188417)

//产生长度为length的随机字符串

　char pSymbol[] = {'~','`','!','@','#','$','%','^','&',
　　　　'*','(',')','_','+','-','=','{','}','|','[',']',
　　　　':',';','<','>','?',
　　　　',','.','\"','\\','\'','/'};

char* getRandomString(int length)
{
int nRand, i;
char* string;
srand((unsigned) time(NULL ));
if ((string = (char*) malloc(length + 1)) == NULL )
return NULL ;

for (i = 0; i < length - 1; i++)
{
nRand = rand() % (sizeof(pSymbol) + 26 * 2 + 10);
if (nRand >= 0)
{
if (nRand < 26)
string[i] = 'A' + nRand;
else if (nRand < 52)
string[i] = 'a' + nRand - 26;
else if (nRand < 62)
string[i] = '1' + nRand - 52;
else if(nRand - 62 < sizeof(pSymbol))
string[i] = pSymbol[nRand - 62];
else
string[i] = 'x';
}
else
string[i] = 'x';
}
string[length] = '\0';
return string;
}