在C中以字节为单位将数据从一个数组传输到另一个数组

So I have two dynamically allocated integer variables (A and B). Each of them is of size 12 which makes each of 48 bytes. I want to transfer data from one to another in bytes basis and want to complete the transfer in 32 rounds (loops). I would describe below what I am trying to achieve:

所以我有两个动态分配的整数变量（A和B）。它们中的每一个都是12的大小，每个都是48个字节。我想以字节为基础将数据从一个传输到另一个，并希望在32轮（循环）中完成传输。我将在下面描述我想要实现的目标：

• Round 1 : First 2 Bytes (bytes 1 and 2) of array A to Array B
• 第1轮：阵列A到阵列B的前2个字节（字节1和2）
• Round 2 : Next 2 Bytes (bytes 3 and 4) of array A to array B
• 第2轮：接下来是阵列A到阵列B的2个字节（字节3和4）

Goes on transferring 2 Bytes up to round 16. In round 16, 31st and 32nd bytes would be transferred.

继续将2个字节传输到第16轮。在第16轮中，将传输第31个和第32个字节。

Then from round 17 to 32 transfer rate would be 1 Bytes/ Round, i.e.

然后从第17轮到第32轮，传输速率为1字节/圆形，即

• Round 17 : 33rd Byte from A to B
• 第17轮：从A到B的第33个字节
• Round 18 : 34th Byte from A to B
• 第18轮：从A到B的第34个字节

......

......

• Round 32 : 48th Byte from A to B
• 第32轮：从A到B的第48个字节

Below I have attached a code snippet :

下面我附上了一段代码：

int *A,*B;

    A = (int *)malloc(12*sizeof(int));
    B = (int *)malloc(12*sizeof(int));

    for(int i= 0;i<12;i++)
     A[i] = i+1;

    for(int i=0;i<32;i++){

      if(i<16)
        //Transfer two byte from A to B in first 16 rounds, 2 bytes/round
      else
       // transfer 1 byte from A to B in next 16 rounds, 1 byte/round
    }

    free(A);
    free(B);

I can understand that this might be achieved using memcpy but I am confused in performing the address calculation. I am not sure if I am taking the correct approach. Please let me know if I am clear enough in my explanation. Any help would be very much appreciated. Thank you.

我可以理解这可以使用memcpy实现，但我在执行地址计算时感到困惑。我不确定我是否采取了正确的方法。如果我在解释中足够清楚，请告诉我。任何帮助将非常感谢。谢谢。

1 个解决方案

#1

You need to use char* pointers to access individual bytes of the buffers, and uint16_t* for the 2-byte blocks.

您需要使用char *指针来访问缓冲区的各个字节，并使用uint16_t *来表示2字节块。

char *cA = (char *)A;
char *cB = (char *)B;

uint16_t *iA = (uint16_t *)A;
uint16_t *iB = (uint16_t *)B;

for(int i=0;i<32;i++){

    if(i<16) {
        //Transfer two byte from A to B in first 16 rounds, 2 bytes/round
        iB[i] = iA[i];
    }
    else {
        // transfer 1 byte from A to B in next 16 rounds, 1 byte/round
        cB[16 + i] = cA[16 + i];
    }
 }