void printchar(unsigned char c)
{
        if(isprint(c))
                printf("%c",c);
        else
                printf(".");
}
void dumpcode(unsigned char *buff, int len)
{
        int i;
        for(i=0;i<len;i++)
        {
                if(i%16==0)
                        printf("0x%08x  ",&buff[i]);
                printf("%02x ",buff[i]);
                if(i%16-15==0)
                {
                        int j;
                        printf("  ");
                        for(j=i-15;j<=i;j++)
                                printchar(buff[j]);
                        printf("\n");
                }
        }
        if(i%16!=0)
        {
                int j;
                int spaces=(len-i+16-i%16)*3+2;
                for(j=0;j<spaces;j++)
                        printf(" ");
                for(j=i-i%16;j<len;j++)
                        printchar(buff[j]);
        }
        printf("\n");
}