unsigned long datapack(void *inBuf, unsigned long len, void *outBuf) { WORD16 *hdr; BYTE *in = (BYTE *)inBuf; BYTE *out = (BYTE *)outBuf; BYTE *pscrc; BYTE *ptr = out; unsigned long i; unsigned long fcs = ~(crc32_le(~0, in, len)); *ptr++ = 0x55; *ptr++ = 0xAA; hdr = (WORD16 *)ptr; ptr += 2; *ptr++ = 0x7e; *ptr++ = 0x7e; for (i = 0; i < len; i++) { switch (in[i]) { case 0x7d: *ptr++ = 0x7d; *ptr++ = 0x5d; break; case 0x7e: *ptr++ = 0x7d; *ptr++ = 0x5e; break; default: *ptr++ = in[i]; break; } } pscrc = (BYTE *)&fcs; for (i = 0; i < 4; i++, pscrc++) { switch (*pscrc) { case 0x7d: *ptr++ = 0x7d; *ptr++ = 0x5d; break; case 0x7e: *ptr++ = 0x7d; *ptr++ = 0x5e; break; default: *ptr++ = *pscrc; break; } } *ptr++ = 0x7e; *ptr++ = 0x7e; *hdr = ptr - out - 4; return ptr - out; } 转python 程序

以下是将该C语言函数转换为Python程序的代码：

import struct
from binascii import crc32

def datapack(inBuf, len, outBuf):
    inBytes = inBuf.encode('latin1')
    out = bytearray()
    fcs = ~(crc32(inBytes) & 0xffffffff)
    out.append(0x55)
    out.append(0xAA)
    out.extend(struct.pack('<H', len))
    out.append(0x7e)
    out.append(0x7e)
    for i in range(0, len):
        if inBytes[i] == 0x7d:
            out.append(0x7d)
            out.append(0x5d)
        elif inBytes[i] == 0x7e:
            out.append(0x7d)
            out.append(0x5e)
        else:
            out.append(inBytes[i])
    pscrc = bytearray(struct.pack('<I', fcs))
    for i in range(0, 4):
        if pscrc[i] == 0x7d:
            out.append(0x7d)
            out.append(0x5d)
        elif pscrc[i] == 0x7e:
            out.append(0x7d)
            out.append(0x5e)
        else:
            out.append(pscrc[i])
    out.append(0x7e)
    out.append(0x7e)
    return bytes(out)

在Python中，需要使用`struct`模块来进行二进制数据的打包和解包，并使用`binascii`模块中的`crc32`函数来计算CRC32校验值。函数中的`encode('latin1')`操作是将字符串转换为字节串。