请教如何发送和接收struct结构? , ACE网络编程开发|开源框架

hqa_shmily 发表于 2008-5-14 10:16:10

请教如何发送和接收struct结构?

比如,我的客户端有一个消息为:
struct MSG
{
int id;
char name;
};

我应该如何把这一个struct消息发送给服务端呢?而服务端接收后也可以以同样一个struct来保存所接收到的数据?
请教大虾们 connect和acceptor 应该做哪些工作,如何做以及应注意的要点是什么??

peakzhang 发表于 2008-5-14 15:56:49

TCP网络传输是流，只认字节流，不认结构的。
所以即使你可以从字节流中重建出结构 - 很简单，直接按结构体读进去，但可能遇到字节不足、跨越边界的情况，必须谨慎。

peakzhang 发表于 2008-5-14 15:57:04

和connect / acceptor没什么关系

marry 发表于 2008-11-18 17:08:35

我也遇到同样的问题，原来服务端和客户端都是用TCPSOCKET编写的，现在服务端想用ACE编写（移植到LINUX上）处理客户端发来的STUCT，不知道如何处理，比较麻烦的事情，希望知晓的老大摆脱指点迷经，给个简短的代码都可以！这里先写过

typedef struct _User          //用户信息
{
int    id;
char name;
char password;
char question;
char result;
}User;

就是想让ACE处理这个struct,然后发送下面的数据包标识，很是麻烦嗷

typedef enum _FLAG          //数据包的标记
{
LOGIN,
LOGINFAULT,
LOGINSUCCESS
}FLAG;

想找处理这个方面的源码都找不到。两天了，累死了！！

[ 本帖最后由 marry 于 2008-11-18 17:16 编辑 ]

marry 发表于 2008-11-18 17:09:46

我随时关注，等待好人的降临！

winston 发表于 2008-11-18 17:42:59

这有何难啊，拼数据呀。

看看ACE的例子：
void AIO_Input_Handler::handle_read_stream
(const ACE_Asynch_Read_Stream::Result &result) {
if (!result.success () || result.bytes_transferred () == 0)
delete this;
else if (result.bytes_transferred () < result.bytes_to_read ())
reader_.read (*mblk_, result.bytes_to_read () -
               result.bytes_transferred ());
else if (mblk_->length () == LOG_HEADER_SIZE) {
ACE_InputCDR cdr (mblk_);

ACE_CDR::Boolean byte_order;
cdr >> ACE_InputCDR::to_boolean (byte_order);
cdr.reset_byte_order (byte_order);

ACE_CDR::ULong length;
cdr >> length;

mblk_->size (length + LOG_HEADER_SIZE);
reader_.read (*mblk_, length);
}
else {
if (OUTPUT_HANDLER::instance ()->put (mblk_) == -1)
   mblk_->release ();

ACE_NEW_NORETURN
   (mblk_, ACE_Message_Block (ACE_DEFAULT_CDR_BUFSIZE));
ACE_CDR::mb_align (mblk_);
reader_.read (*mblk_, LOG_HEADER_SIZE);
}
}
其他的也有：
int Logging_Handler::recv_log_record (ACE_Message_Block *&mblk)
{
// Put <logging_peer>'s hostname in new message block.
ACE_INET_Addr peer_addr;
logging_peer_.get_remote_addr (peer_addr);
mblk = new ACE_Message_Block (MAXHOSTNAMELEN + 1);
peer_addr.get_host_name (mblk->wr_ptr (), MAXHOSTNAMELEN);
mblk->wr_ptr (ACE_OS::strlen (mblk->wr_ptr ()) + 1); // Go past name

// Allocate a message block for the payload; initially at least
// large enough to hold the header, but needs some room for
// alignment.
ACE_Message_Block *payload =
new ACE_Message_Block (ACE_DEFAULT_CDR_BUFSIZE);
// Align the Message Block for a CDR stream
ACE_CDR::mb_align (payload);
if (logging_peer_.recv_n (payload->wr_ptr (), 8) == 8) {
payload->wr_ptr (8);             // Reflect addition of 8 bytes

// Create a CDR stream to parse the 8-byte header.
ACE_InputCDR cdr (payload);

// Extract the byte-order and use helper methods to
// disambiguate octet, booleans, and chars.
ACE_CDR::Boolean byte_order;
cdr >> ACE_InputCDR::to_boolean (byte_order);

// Set the byte-order on the stream...
cdr.reset_byte_order (byte_order);

// Extract the length
ACE_CDR::ULong length;
cdr >> length;

// Ensure there's sufficient room for log record payload.
ACE_CDR::grow (payload, 8 + ACE_CDR::MAX_ALIGNMENT + length);

// Use <recv_n> to obtain the contents.
if (logging_peer_.recv_n (payload->wr_ptr (), length) > 0) {
   payload->wr_ptr (length); // Reflect additional bytes
   // Chain the payload to mblk via the contination field.
   mblk->cont (payload);
   return length;
}
}
// Error cases end up here, so we need to release the memory to
// prevent a leak.
payload->release ();
payload = 0;
mblk->release ();
mblk = 0;
return -1;
}

int Logging_Handler::write_log_record (ACE_Message_Block *mblk)
{
// Peer hostname is in the <mblk> and the log record data
// is in its continuation.
if (log_file_->send_n (mblk) == -1)
return -1;
if (ACE::debug ()) {
// Build a CDR stream from the log record data.
ACE_InputCDR cdr (mblk->cont ());
ACE_CDR::Boolean byte_order;
ACE_CDR::ULong length;
// Extract the byte-order and length, ending up at the start
// of the log record itself. Use the byte order to properly
// set the CDR stream for extracting the contents.
cdr >> ACE_InputCDR::to_boolean (byte_order);
cdr.reset_byte_order (byte_order);
cdr >> length;
ACE_Log_Record log_record;
cdr >> log_record;// Finally extract the <ACE_log_record>.
log_record.print (mblk->rd_ptr (), 1, cerr);
}
return mblk->total_length ();
}

int Logging_Handler::log_record ()
{
ACE_Message_Block *mblk = 0;
if (recv_log_record (mblk) == -1)
return -1;
else {
int result = write_log_record (mblk);
mblk->release (); // Free up the contents.
return result == -1 ? -1 : 0;
}
}

winston 发表于 2008-11-18 17:43:26

要看书。
神说：学好ACE，要看书。。。

marry 发表于 2008-11-18 17:50:11

多谢老兄，哎，书籍太难买到了，抢手货，跑了整个西安，只买个一卷，比较郁闷的事情，我研究下老兄发代码

marry 发表于 2008-11-18 17:53:21

嗷，下面那段是日志服务器的，老兄说的拼数据3个字比较经典，提醒了我，我仔细研究下，客户端我懒得用ACE写，只要服务端能移植到LINUX就OK，深埋显示器中。。。。。。

一次读一个STRUCT内容，读5次，然后拼在一块，在然后进行后面的处理:lol :lol 这个东西看来就是挺麻烦的，呵呵

我曾经想用集中写入和读的方法，这样简单点，但是实现起来确实挺不容易，初次接触ACE，比较笨拙

[ 本帖最后由 marry 于 2008-11-18 17:57 编辑 ]

winston 发表于 2008-11-18 21:37:46

ACE的书，在网上买。以前已经重印了一次，应该还能买的到。实在不行，淘宝上找找。

页: [1]

ACE Developer's Archiver

请教如何发送和接收struct结构?