websocket 传输数据帧打包 (client端)

 /*
 Vertion: 0.2.1
 date:    2015.8.11
 content: gcc 编译通过
 */

 //websocket 传输数据帧打包  client端
 //参数：src 为输入字符串
 //      len为输入字串src长度
 //      mask为4个字节掩码值
 //      des 为输出掩码后字节数组。
 //      sum 为输出des实际长度 (len+6: len<=125
 //                             len+8: 125<len<=65535
 //                             len+10: len>65535
 //                             0: 组帧失败)
 void maskpak(unsigned char src[],
          unsigned int len,
          unsigned char mask[],
          unsigned char des[],
          unsigned int *sum)
 {
     unsigned char FIN    =0X80;
     unsigned char RSV1   =0X00;
     unsigned char RSV2   =0X00;
     unsigned char RSV3   =0X00;
     unsigned char OPCODE =0X01; //文本帧
     unsigned char MASK   =0X80; //掩码标识
     unsigned char PLEN   =0X00;

     int index=;
     int i; 

         des[index++]= FIN +RSV1 +RSV2 +RSV3 +OPCODE;

     if(len<=)
     {
         PLEN =len;
     }else if(len<=0XFFFF)
     {
         PLEN =;
     }else
     {
         PLEN =;
     }
     des[index++]= MASK +PLEN;

     //网络字节序标准为: 大端方式(即高字节在前低字节在后)
     if(PLEN<=)
     {
         *sum= len+;
     }
     else if(==PLEN)
     {
         unsigned short temp;
         temp =len;
         des[index++] =(unsigned char)(temp>>);
         des[index++] =(unsigned char)temp;
         *sum= len+;
     }else if(==PLEN)
     {
         unsigned int temp;
         temp =len;
         des[index++] =(unsigned char)(temp>>);
         des[index++] =(unsigned char)(temp>>);
         des[index++] =(unsigned char)(temp>>);
         des[index++] =(unsigned char)temp;
         *sum=len+;
     }else
     {
         *sum= ;
         return;
     }

     for(i=;i<;i++)
     {
         des[index++] =mask[i];
     }

     for(i=;i<len;i++)
     {
         des[index++] =src[i]^mask[i%];
     }
 }

 // 测试代码
 int main(int argc,char *argv)
 {
     unsigned char src[];
     unsigned char mask[]= {0X00,0X00,0X00,0X00};
     unsigned char des[+];
     unsigned int len = ;
     unsigned int sum;

     int i;

     for (i=;i<;i++)
     {
         src[i] = i;
     }
     maskpak(src,len,mask,des,&sum);

     printf("SUM=%d  \r\n",sum);
     for(i=;i<sum;i++)
     {
         printf("%.2X ",(unsigned char)(des[i]));
     }

     return ;
 }