我从.Net应用程序发送1404浮点值,通过udp套接字组成了5616字节。我没有例外关闭此操作。如何轻松解决在Wsock2上的10040消息太长错误
但是,接收这些数据的程序是一个C++应用程序,并且在接收到这种数量的数据时,我得到一个10040消息太长的错误。
显然1480bytes是Wsock2中消息的最大可能大小。
什么是最简单,最干净的方法来解决这个问题?
谢谢!
编辑:发布一些代码:
这是我的插座J_Receive类:
#include "J_Receive.h"
#include <stdio.h>
#include <fcntl.h>
#include <sys/types.h>
#if defined (WIN32) && !defined(__CYGWIN__)
#include <winsock.h>
#else
#include <unistd.h>
#include <sys/uio.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <netdb.h>
#include <arpa/inet.h>
#include <sys/time.h>
#endif
#include <string.h>
#include <iostream>
using namespace sockets;
J_Recibir::J_Recibir(void)
{
_port = 0;
_initialized = false;
_buffer = 0L;
}
J_Recibir::~J_Recibir(void)
{
#if defined (WIN32) && !defined(__CYGWIN__)
closesocket(_so);
#else
close(_so);
#endif
}
bool J_Recibir::init(void)
{
#if defined(WIN32) && !defined(__CYGWIN__)
WORD version = MAKEWORD(1,1);
WSADATA wsaData;
// First, we start up Winsock
WSAStartup(version, &wsaData);
#endif
if(_port == 0)
{
fprintf(stderr, "Receiver::init() - port not defined\n");
return false;
}
if((_so = socket(AF_INET, SOCK_DGRAM, 0)) < 0)
{
perror("Socket");
return false;
}
/*int buffsize = 50000;
setsockopt(_so, SOL_SOCKET, SO_RCVBUF, (const char*)&buffsize, sizeof(buffsize));*/
#if defined (WIN32) && !defined(__CYGWIN__)
// const BOOL on = TRUE;
// setsockopt(_so, SOL_SOCKET, SO_REUSEADDR, (const char*) &on, sizeof(int));
#else
int on = 1;
setsockopt(_so, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on));
#endif
// struct sockaddr_in saddr;
saddr.sin_family = AF_INET;
saddr.sin_port = htons(_port);
#if defined (WIN32) && !defined(__CYGWIN__)
saddr.sin_addr.s_addr = htonl(INADDR_ANY);
#else
saddr.sin_addr.s_addr = 0;
#endif
if(bind(_so, (struct sockaddr *)&saddr, sizeof(saddr)) < 0)
{
perror("bind");
return false;
}
u_long iMode = 1; // 1 para No bloqueante, 0 para bloqueante
ioctlsocket(_so, FIONBIO, &iMode);
_initialized = true;
return _initialized;
}
void J_Recibir::setPort(const short port)
{
_port = port;
}
void J_Recibir::setBuffer(void *buffer, const unsigned int size)
{
_buffer = buffer;
_buffer_size = size;
}
int J_Recibir::sync(void)
{
if(!_initialized) init();
if(_buffer == 0L)
{
fprintf(stderr, "Receiver::sync() - No buffer\n");
return -1;
}
#if defined(__linux) || defined(__FreeBSD__) || defined(__APPLE__)
socklen_t
#else
int
#endif
size = sizeof(struct sockaddr_in);
fd_set fdset;
FD_ZERO(&fdset);
FD_SET(_so, &fdset);
struct timeval tv;
tv.tv_sec = 0;
tv.tv_usec = 0;
#if defined (WIN32) && !defined(__CYGWIN__)
// saddr.sin_port = htons(_port);
recvfrom(_so, (char *)_buffer, _buffer_size, 0, (sockaddr*)&saddr, &size);
// recvfrom(sock_Receive, szMessage, 256, 0, (sockaddr*)&addr_Cli, &clilen)
int err = WSAGetLastError();
if (err!=0){
fprintf(stderr, "Receiver::sync() - error %d\n",err);
perror("Error: ");
}
while(select(_so+1, &fdset, 0L, 0L, &tv))
{
if(FD_ISSET(_so, &fdset))
{
recvfrom(_so, (char *)_buffer, _buffer_size, 0, (sockaddr*)&saddr, &size);
}
}
#else
recvfrom(_so, (caddr_t)_buffer, _buffer_size, 0, 0, &size);
while(select(_so+1, &fdset, 0L, 0L, &tv))
{
if(FD_ISSET(_so, &fdset))
{
recvfrom(_so, (caddr_t)_buffer, _buffer_size, 0, 0, &size);
}
}
#endif
if (err!=0) return -1;
else return 0;
}
这是我如何调用接收功能:
sockets::J_Receiver receiverGUI = new sockets::J_Recibir();
receiverGUI->setPort(4020);
nDatosGUI = 1404;
float* datosGUI = new datosGUI[nDatosGUI ];
receiverGUI->setBuffer((void *)datosGUI, sizeof(float)*nDatosGUI);
我从1404浮动缓冲区发送并接收到1404浮动缓冲区。这不应该是相同的大小? – 2012-02-22 09:06:55
不,您的缓冲区需要足够大以处理任何可能到达的数据报。除了防火墙之外,您可以随时随地从任何地方接收任何大小的数据报,而不仅仅是发送程序。所以至少你需要防止那些阻塞你的接收队列。但它更可能是你发送的数据超过你的意思。这将有助于查看代码。 – 2012-02-22 15:55:02
你没事,我正在调整我的缓冲区大小,现在它的大小为5616字节,但现在程序只是永远挂起,这是否与阻塞套接字有关? – 2012-02-23 09:45:38