I'm having a problem with a UDPSocket wrapper I've written. I have a high bandwidth low latency local network over which I'm sending UDP packets back and forth. I don't have a concern too much for reliability of packet arrival, but it is incredibly important that the packets that do arrive do so quickly. Here's the relevant code for setting up a socket:
bool UDPSocket::create() {
int on = 1;
#ifdef WIN32
if(WSAStartup(MAKEWORD(1,1), &SocketInfo) != 0) {
MessageBox(NULL, "Cannot initialize WinSock", "WSAStartup", MB_OK);
}
#endif
m_sock = socket(PF_INET, SOCK_DGRAM, 0);
#ifdef WIN32
if(setsockopt(m_sock, SOL_SOCKET, SO_REUSEADDR, (const char*)&on, sizeof(on)) == SOCKET_ERROR)
return false;
#else
if(setsockopt(m_sock, SOL_SOCKET, SO_REUSEADDR, (const char*)&on, sizeof(on)) == -1)
return false;
#endif
addrLen = sizeof(struct sockaddr);
return true;
}
bool UDPSocket::bind(const int port) {
if(!is_valid())
return false;
m_addr.sin_family = AF_INET;
m_addr.sin_addr.s_addr = htonl(INADDR_ANY);
m_addr.sin_port = htons(port);
if(::bind(m_sock, (struct sockaddr*)&m_addr, sizeof(m_addr))<0) {
std::cout << "UDPSocket: error on bind" << std::endl;
return false;
}
return true;
}
bool UDPSocket::send(const std::string s) const {
const char* buf = s.c_str();
::sendto(m_sock, buf, strlen(buf), 0, (const sockaddr*)&clientAddr, addrLen);
return true;
}
bool UDPSocket::setDestination(const std::string ip, const int port) {
memset(&clientAddr, 0, sizeof(clientAddr));
clientAddr.sin_family = AF_INET;
clientAddr.sin_addr.s_addr = inet_addr(ip.c_str());
clientAddr.sin_port = htons(port);
return true;
}
int UDPSocket::recv(std::string& s) const {
char buffer[MAXRECV + 1];
struct timeval tv;
fd_set fdset;
int rc, nread;
memset(&buffer, 0, sizeof(buffer));
FD_ZERO(&fdset);
FD_SET(m_sock, &fdset);
tv.tv_sec = 0;
tv.tv_usec = m_timeout;
rc = select(m_sock + 1, &fdset, (fd_set *) 0, (fd_set *) 0, &tv);
if(FD_ISSET(m_sock, &fdset)) {
#ifdef WIN32
nread = ::recvfrom(m_sock, buffer, MAXRECV, 0, (sockaddr*)&clientAddr, const_cast< int * __w64 >(&addrLen));
#else
nread = ::recvfrom(m_sock, buffer, MAXRECV, 0, (sockaddr*)&clientAddr, (socklen_t*)&addrLen);
#endif
if(nread < 0) {
return -1;
} else if(nread == 0) {
return 0;
}
s = std::string(buffer);
return nread;
} else {
return 0;
}
}
void UDPSocket::set_non_blocking(const bool b) {
mNonBlocking = b;
#ifdef WIN32
u_long argp = b ? 1 : 0;
ioctlsocket(m_sock, FIONBIO, &argp);
#else
int opts = fcntl(m_sock, F_GETFL);
if(opts < 0) return;
if(b)
opts |= O_NONBLOCK;
else
opts &= ~O_NONBLOCK;
fcntl(m_sock, F_SETFL, opts);
#endif
}
My user code, on both ends, create a "sending" and "receiving" UDPSocket and bind them to their respective ports, then use send() to send data and recv() to receive. On one hand, the linux side seems to receive practically immediately, but the Windows side has a delay up to 1 second before receiving data. However, ::recv() never returns 0 in this time. Am I missing something obvious?
have you tried all four combinations (linux->linux, win->linux, linux->win, win->win)? which have delays and which not?
also, use a packet sniffer (like tcpdump or wireshark) to see if the delay is before or after hitting the wire.
It's not a direct answer. May be you can try tools like ttcp (http://www.pcausa.com/Utilities/pcattcp.htm), which can both test tcp and udp performance. And, you may also check their source code, which is in public domain.
If you've got the time to experiment, try an IOCP version of the code.
I never trusted the win select implementation, with its 64 socket limit.
Related
Using winsock, I got a client and a server, when connect is done and i send a message the first time i can recv it in the server but after that when I do a time loop i can not show them on the screen. the send message inside the time loop does not return an error. I know this is a weird problem but if you take a look at timerCb that's where the send function is, it does not return an error but in my server i cannot print it. I have also tried making a new while loop with a parameter of recv it still did not work.
This is my client,
char receivingMessage[1000];
char messageInitiation[90] = "Hello YUMATKARA, conn pls bro hhhasf7sasflljh89";
VOID CALLBACK timerCb(HWND hwnd, UINT uMsg, UINT_PTR idEvent, DWORD dwTime);
//main
SetTimer(NULL, 0, 3600, timerCb);
if(WSAStartup(MAKEWORD(2, 2), &ws) != 0){
printf("WSA err %d \n", GetLastError());
}else{
}
if((s = socket(AF_INET, SOCK_STREAM, IPPROTO_TCP)) == INVALID_SOCKET){
printf("Invalid Socket \n");
}else{
printf("socket binded \n");
}
rmtServer.sin_addr.s_addr = inet_addr("127.0.0.1");
rmtServer.sin_port = htons(4743);
rmtServer.sin_family = AF_INET;
if((connect(s, (struct sockaddr*)&rmtServer, sizeof(struct sockaddr_in))) != 0){
printf("\n err %d", GetLastError());
}else{
printf("\n connected");
send(s, messageInitiation, strlen(messageInitiation), 0);
recv(s, receivingMessage, 1000, 0);
printf("\n %s", receivingMessage);
int liop;
liop = strcmp(receivingMessage, "I got you!!");
if(liop == 0){
connectedYet = TRUE;
}
printf("\n is it true: ? %d\n", connectedYet);
}
while(GetMessage(&message, NULL, 0, 0) > 0){
TranslateMessage(&message);
DispatchMessage(&message);
}
//outside main
VOID CALLBACK timerCb(HWND hwnd, UINT uMsg, UINT_PTR idEvent, DWORD dwTime){
char *msgg = "Hello YUMATKARA, conn pls bro hhhasf7sasflljh89";
printf("\n%s\n", "timing");
if(send(s, msgg, strlen(msgg), 0) == SOCKET_ERROR){
printf("err :%d\n", GetLastError());
}
}
And this is my server
#include <windows.h>
#include <winsock2.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
int WINAPI WinMain(HINSTANCE hInstance, HINSTANCE hPrevInstance, PSTR szCmdParam, int iCmdShow) {
MSG message;
WSADATA ws;
SOCKET s, incomingSocket;
struct sockaddr_in server, client;
char incomingMessage[1800];
int recvState;
WSAStartup(MAKEWORD(2, 2), &ws);
s = socket(AF_INET, SOCK_STREAM, IPPROTO_TCP);
server.sin_port = htons(4743);
server.sin_addr.s_addr = inet_addr("127.0.0.1");
server.sin_family = AF_INET;
bind(s, (struct sockaddr *)&server, sizeof(server));
listen(s, 1300);
int g = sizeof(struct sockaddr_in);
while((incomingSocket = accept(s, (struct sockaddr *)&client, &g)) != INVALID_SOCKET){
printf("%s\n", inet_ntoa(client.sin_addr));
printf("conn\n");
if((recvState = recv(incomingSocket, incomingMessage, 2500, 0)) == SOCKET_ERROR){
}else{
int as;
if((as = strcmp(incomingMessage, "Hello YUMATKARA, conn pls bro hhhasf7sasflljh89")) == 0){
printf("\n identical");
send(incomingSocket, "I got you!!", 11, 0);
}
printf("\n :%s\n", incomingMessage);
}
}
if(incomingSocket == INVALID_SOCKET){
printf("invalid socket");
}
return 0;
}
UPDATE
I have added this in my server code, before return 0 it does not display anything at all.
while((recvState = recv(incomingSocket, incomingMessage, 50, 0)) > 0) {
printf("\n new msg %s\n", incomingMessage);
}
TCP is a byte stream, not message-oriented like you are expecting.
recv() is not guaranteed to return complete messages. It could return as little as 1 byte, or it could return partial bytes from a message, or even bytes from multiple messages. You have to handle buffering and message framing in your code logic. And pay attention to its return value so you know how much it actually read. If you are expecting more data than is read, you have to call recv() again to read the rest, potentially many times. So use a loop.
So, either:
Have the sender send a string's length as a fixed-length value before then sending the actual characters. Then have the receiver read the length to know how many characters to read.
Have the sender send a unique terminator after each string, like a nul character or even a CRLF, then the receiver can keep reading until it encounters the terminator.
As for send(), it is not guaranteed to send complete data, either. It could send as few as 1 byte, or at least less than what you requested. So you have to pay attention to its return value, too, to know how much it actually sent. If it doesn't send everything in one go, you have to call it again to send any remaining data, potentially many times. So use a loop.
For example, try something more like this:
Client:
const char messageInitiation* = "Hello YUMATKARA, conn pls bro hhhasf7sasflljh89";
char* readStr(SOCKET s)
{
char *str = NULL;
char buffer[100], ch;
int buf_len = 0, str_len = 0, ret;
do
{
ret = recv(s, &ch, 1, 0);
if (ret == SOCKET_ERROR)
{
printf("recv err %d\n", WSAGetLastError());
return SOCKET_ERROR;
}
if (ch == '\0')
break;
if (buf_len == sizeof(buffer))
{
char *newstr = (char*) realloc(str, str_len + buf_len + 1);
if (!newstr)
{
printf("memory err\n");
free(str);
return NULL;
}
str = newstr;
memcpy(str + str_len, buffer, buf_len);
str_len += buf_len;
buf_len = 0;
}
buffer[buf_len++] = ch;
}
while (true);
if (buf_len > 0)
{
char *newstr = (char*) realloc(str, str_len + buf_len + 1);
if (!newstr)
{
printf("memory err\n");
free(str);
return NULL;
}
str = newstr;
memcpy(str, buffer, buf_len);
str_len += buf_len;
}
str[str_len] = '\0';
return str;
}
int sendStr(SOCKET s, const char *str)
{
const unsigned char *pstr = (const unsigned char*) str;
int len = strlen(str) + 1, ret;
do
{
ret = send(s, pstr, len, 0);
if (ret == SOCKET_ERROR)
{
printf("send err %d\n", WSAGetLastError());
return SOCKET_ERROR;
}
pstr += ret;
len -= ret;
}
while (len > 0);
return 0;
}
/* alternatively:
int readAll(SOCKET s, void *data, int len)
{
unsigned char *pdata = (unsigned char *) data;
int ret;
while (len > 0)
{
ret = recv(s, pdata, len, 0);
if (ret == SOCKET_ERROR)
{
printf("recv err %d\n", WSAGetLastError());
return SOCKET_ERROR;
}
pdata += ret;
len -= ret;
}
return 0;
}
int readStr(SOCKET s)
{
int32_t len = 0;
if (readAll(s, &len, sizeof(len)) == SOCKET_ERROR)
return NULL;
char *str = (char*) malloc(len + 1);
if (!str)
{
printf("memory err\n");
return NULL;
}
if (readAll(s, str, len) == SOCKET_ERROR)
{
free(str);
return NULL;
}
str[len] = '\0';
return str;
}
int sendAll(SOCKET s, const void *data, int len)
{
const unsigned char *pdata = (const unsigned char*) data;
int ret;
while (len > 0)
{
ret = send(s, pdata, len, 0);
if (ret == SOCKET_ERROR)
{
printf("send err %d\n", WSAGetLastError());
return SOCKET_ERROR;
}
pdata += ret;
len -= ret;
}
return 0;
}
int sendStr(SOCKET s, const char *str)
{
int32_t len = strlen(str) + 1;
int ret = sendAll(s, &len, sizeof(len));
if (ret == 0)
ret = sendAll(s, str, len);
return ret;
}
*/
VOID CALLBACK timerCb(HWND hwnd, UINT uMsg, UINT_PTR idEvent, DWORD dwTime)
{
printf("\n%s\n", "timing");
if (!sendStr(s, messageInitiation))
PostQuitMessage(0);
}
int main()
{
WSADATA ws;
int ret = WSAStartup(MAKEWORD(2, 2), &ws);
if (ret != 0)
{
printf("WSA err %d\n", ret);
return -1;
}
SOCKET s = socket(AF_INET, SOCK_STREAM, IPPROTO_TCP);
if (s == INVALID_SOCKET)
{
printf("socket err %d\n", WSAGetLastError());
WSACleanup();
return -1;
}
printf("socket created\n");
struct sockaddr_in rmtServer = {};
rmtServer.sin_family = AF_INET;
rmtServer.sin_addr.s_addr = inet_addr("127.0.0.1");
rmtServer.sin_port = htons(4743);
if (connect(s, (struct sockaddr*)&rmtServer, sizeof(struct sockaddr_in)) == SOCKET_ERROR)
{
printf("connect err %d\n", WSAGetLastError());
closesocket(s);
WSACleanup();
return -1;
}
printf("connected\n");
if (sendStr(s, messageInitiation) != 0)
{
closesocket(s);
WSACleanup();
return -1;
}
char *receivingMessage = recvStr(s);
if (!receivingMessage)
{
closesocket(s);
WSACleanup();
return -1;
}
printf("%s\n", receivingMessage);
BOOL connectedYet = (strcmp(receivingMessage, "I got you!!") == 0);
printf("is it true: ? %d\n", connectedYet);
free(receivingMessage);
SetTimer(NULL, 0, 3600, timerCb);
MSG message;
while (GetMessage(&message, NULL, 0, 0) > 0)
{
TranslateMessage(&message);
DispatchMessage(&message);
}
closesocket(s);
WSACleanup();
return 0;
}
Server:
#include <windows.h>
#include <winsock2.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
// see client code above
char* readStr(SOCKET s);
int sendStr(SOCKET s, const char *str);
int main()
{
struct sockaddr_in server = {0}, client;
WSADATA ws;
int ret = WSAStartup(MAKEWORD(2, 2), &ws);
if (ret != 0)
{
printf("WSA err %d\n", ret);
return -1;
}
SOCKET s = socket(AF_INET, SOCK_STREAM, IPPROTO_TCP);
if (s == INVALID_SOCKET)
{
printf("socket err %d\n", WSAGetLasatError());
WSACleanup();
return -1;
}
struct sockaddr_in server = {};
server.sin_family = AF_INET;
server.sin_addr.s_addr = inet_addr("127.0.0.1");
server.sin_port = htons(4743);
ret = bind(s, (struct sockaddr *)&server, sizeof(server));
if (ret == SOCKET_ERROR)
{
printf("bind err %d\n", WSAGetLastError());
closesocket(s);
WSACleanup();
return -1;
}
if (listen(s, 10) == SOCKET_ERROR)
{
printf("listen err %d\n", WSAGetLastError());
closesocket(s);
WSACleanup();
return -1;
}
int g, iResult;
struct sockaddr_in client;
do
{
g = sizeof(client);
SOCKET incomingSocket = accept(s, (struct sockaddr *)&client, &g);
if (incomingSocket == INVALID_SOCKET)
{
printf("accept err %d\n", WSAGetLastError());
closesocket(s);
WSACleanup();
return -1;
}
printf("%s conn\n", inet_ntoa(client.sin_addr));
char *incomingMessage = recvStr(incomingSocket);
if (incomingMessage)
{
printf("%s\n", incomingMessage);
if (incomingMessage, "Hello YUMATKARA, conn pls bro hhhasf7sasflljh89") == 0)
{
printf("identical\n");
sendStr(incomingSocket, "I got you!!");
}
}
closesocket(incomingSocket);
}
while (true);
return 0;
}
I have a broadcast program on my mac, everything is working fine, but if i have more then one network interface, he didn't recieve anything.
So what i now want to do is:
Check which network interfaces are activ on the mac
send to every activ interface a broadcast ( so i have to select which interface i want to use)
recieve the answer (if there is one :) )
Interesting:
the broadcast client is on my WLAN (with a router beetween the devices) and a normal internet connection is on my LAN. If i deactivate the LAN in the system configs, he also didn't find my other device, but if i pull the cable he found the other device... So maybe i didn't have to look which interface is activ and have a look to which interface is connected.
Do u have some tipps or good google keywords for me to do that?
Long time ago, but if someone find my post, here is my solution:
#include <stdint.h>
static uint32 Inet_AtoN(const char * buf)
{
// net_server inexplicably doesn't have this function; so I'll just fake it
uint32 ret = 0;
int shift = 24; // fill out the MSB first
bool startQuad = true;
while ((shift >= 0) && (*buf))
{
if (startQuad)
{
unsigned char quad = (unsigned char)atoi(buf);
ret |= (((uint32)quad) << shift);
shift -= 8;
}
startQuad = (*buf == '.');
buf++;
}
return ret;
}
int Broadcast::BroadcastToAllInterfaces()
{
DEBUG_LOG(1,"Start Broadcast To All Interfaces", "DEv1");
globalDatabase->SetInBroadcast();
moreThenOne = 0;
#if defined(USE_GETIFADDRS)
struct ifaddrs * ifap;
if (getifaddrs(&ifap) == 0)
{
struct ifaddrs * p = ifap;
while (p)
{
uint32 ifaAddr = SockAddrToUint32(p->ifa_addr);
uint32 maskAddr = SockAddrToUint32(p->ifa_netmask);
uint32 dstAddr = SockAddrToUint32(p->ifa_dstaddr);
if (ifaAddr > 0)
{
char ifaAddrStr[32]; Inet_NtoA(ifaAddr, ifaAddrStr);
char maskAddrStr[32]; Inet_NtoA(maskAddr, maskAddrStr);
char dstAddrStr[32]; Inet_NtoA(dstAddr, dstAddrStr);
std::stringstream addr, descss;
std::string addrs, descs;
addr << dstAddrStr;
descss << p->ifa_name;
descss >> descs;
addr >> addrs;
DoABroadcast(dstAddr);
}
p = p->ifa_next;
}
freeifaddrs(ifap);
}
#elif defined(WIN32)
// Windows XP style implementation
// Adapted from example code at http://msdn2.microsoft.com/en-us/library/aa365917.aspx
// Now get Windows' IPv4 addresses table. Once again, we gotta call GetIpAddrTable()
// multiple times in order to deal with potential race conditions properly.
MIB_IPADDRTABLE * ipTable = NULL;
{
ULONG bufLen = 0;
for (int i = 0; i<5; i++)
{
DWORD ipRet = GetIpAddrTable(ipTable, &bufLen, false);
if (ipRet == ERROR_INSUFFICIENT_BUFFER)
{
free(ipTable); // in case we had previously allocated it STILL_RUN
ipTable = (MIB_IPADDRTABLE *)malloc(bufLen);
}
else if (ipRet == NO_ERROR) break;
else
{
free(ipTable);
ipTable = NULL;
break;
}
}
}
if (ipTable)
{
IP_ADAPTER_INFO * pAdapterInfo = NULL;
{
ULONG bufLen = 0;
for (int i = 0; i<5; i++)
{
DWORD apRet = GetAdaptersInfo(pAdapterInfo, &bufLen);
if (apRet == ERROR_BUFFER_OVERFLOW)
{
free(pAdapterInfo); // in case we had previously allocated it
pAdapterInfo = (IP_ADAPTER_INFO *)malloc(bufLen);
}
else if (apRet == ERROR_SUCCESS) break;
else
{
free(pAdapterInfo);
pAdapterInfo = NULL;
break;
}
}
}
for (DWORD i = 0; i<ipTable->dwNumEntries; i++)
{
const MIB_IPADDRROW & row = ipTable->table[i];
// Now lookup the appropriate adaptor-name in the pAdaptorInfos, if we can find it
const char * name = NULL;
const char * desc = NULL;
if (pAdapterInfo)
{
IP_ADAPTER_INFO * next = pAdapterInfo;
while ((next) && (name == NULL))
{
IP_ADDR_STRING * ipAddr = &next->IpAddressList;
while (ipAddr)
{
if (Inet_AtoN(ipAddr->IpAddress.String) == ntohl(row.dwAddr))
{
name = next->AdapterName;
desc = next->Description;
break;
}
ipAddr = ipAddr->Next;
}
next = next->Next;
}
}
char buf[128];
int setUnnamed = 0;
if (name == NULL)
{
sprintf(buf, "unnamed");
name = buf;
setUnnamed = 1;
}
uint32 ipAddr = ntohl(row.dwAddr);
uint32 netmask = ntohl(row.dwMask);
uint32 baddr = ipAddr & netmask;
if (row.dwBCastAddr) baddr |= ~netmask;
char ifaAddrStr[32]; Inet_NtoA(ipAddr, ifaAddrStr);
char maskAddrStr[32]; Inet_NtoA(netmask, maskAddrStr);
char dstAddrStr[32]; Inet_NtoA(baddr, dstAddrStr);
std::stringstream addr, descss;
std::string addrs, descs;
if (setUnnamed == 0)
{
addr << dstAddrStr;
descss << desc;
descss >> descs;
addr >> addrs;
DoABroadcast(baddr);
}
}
free(pAdapterInfo);
free(ipTable);
}
#else
// Dunno what we're running on here!
# error "Don't know how to implement PrintNetworkInterfaceInfos() on this OS!"
#endif
globalDatabase->SetLeaveBroadcast();
return 1;
}
int Broadcast::DoABroadcast(uint32 broadAddr)
{
int askSinlen = sizeof(struct sockaddr_in);
int askBuflen = MAXBUF;
int message;
char buf[512];
int status;
char askBuffer[MAXBUF];
struct sockaddr_in sock_in, client_adress, client_adress2;
#ifdef __APPLE__
socklen_t clientLength;
int askYes = 1;
#else
char askYes = 1;
int clientLength;
WSADATA w;
int result = WSAStartup(MAKEWORD(2, 2), &w);
#endif
int recSocket = socket(AF_INET, SOCK_DGRAM, 0);
if (recSocket <0)
{
#ifdef __APPLE__
close(recSocket);
#else
closesocket(recSocket);
#endif
inBroadcast = false;
return 10;
}
sock_in.sin_addr.s_addr = htonl(INADDR_ANY);
sock_in.sin_port = htons(4028);
sock_in.sin_family = PF_INET;
client_adress.sin_family = PF_INET;
client_adress.sin_port = htons(4029);
client_adress.sin_addr.s_addr = htonl(broadAddr);
askSinlen = sizeof(sock_in);
client_adress2.sin_family = AF_INET;
client_adress2.sin_port = htons(4028);
client_adress2.sin_addr.s_addr = htonl(0xc0a8b2ff);
status = setsockopt(recSocket, SOL_SOCKET, SO_BROADCAST, &askYes, sizeof(askYes));
if (status < 0)
{
#ifdef __APPLE__
close(recSocket);
#else
closesocket(recSocket);
#endif
inBroadcast = false;
return 10;
}
status = bind(recSocket, (struct sockaddr *)&sock_in, askSinlen);
if (status < 0)
{
#ifdef __APPLE__
close(recSocket);
#else
closesocket(recSocket);
#endif
inBroadcast = false;
return 10;
}
askBuflen = sprintf(askBuffer, "Ciao Mac ist hier");
status = sendto(recSocket, askBuffer, askBuflen, 0, (struct sockaddr *)&client_adress, sizeof(client_adress));
fd_set fds;
struct timeval tv;
tv.tv_sec = 2;
tv.tv_usec = 0;
FD_ZERO(&fds);
FD_SET(recSocket, &fds);
int ret;
if ((ret = select(recSocket +1, &fds, NULL, NULL, &tv)) > 0)
{
int e = 0;
while ((ret = select(recSocket + 1, &fds, NULL, NULL, &tv)) > 0)
{
clientLength = sizeof(client_adress2);
message = recvfrom(recSocket, buf, sizeof(buf), 0, (struct sockaddr*) &client_adress2, &clientLength);
if (message == -1)
{
#ifdef __APPLE__
close(recSocket);
#else
closesocket(recSocket);
#endif
inBroadcast = false;
return -5;
}
else
{
std::string hereisyourbroadcast(buf);
}
}
}
else
{
#ifdef __APPLE__
close(recSocket);
#else
closesocket(recSocket);
#endif
inBroadcast = false;
return -6;
}
#ifdef __APPLE__
close(recSocket);
#else
closesocket(recSocket);
#endif
inBroadcast = false;
return 1;
}
Hey there wonderful community!
I'm back with a question regarding a console server application I've made with winsock. It's finally reaching a stage where I would need a to add a GUI, and to do so, I need it to be using the Windows subsystem.
And so I started the migration.
Yet I'm hitting a stack overflow somewhere in my application, and for the life of me I can't figure out where. Perhaps it has to do with WIN being a non-blocking subsystem (hope I used my vocab correctly).
Anyway, I hope to enlist you all as helpers. Many thanks :)
#undef UNICODE
#define WIN32_LEAN_AND_MEAN
#include <windows.h>
#include <winsock2.h>
#include <ws2tcpip.h>
#include <stdlib.h>
#include <stdio.h>
#include <iostream>
#include <string>
#include <conio.h>
// Need to link with Ws2_32.lib
#pragma comment (lib, "Ws2_32.lib")
// #pragma comment (lib, "Mswsock.lib")
int minitialize();
int msend(char msendbuf[512]);
char* mrecv(bool show);
int mshutdown();
void GoToXY(int column, int line);
int scroll(void);
int printm(char *inp);
int printm(char *inp, DWORD color);
int mexit();
char *vir = "true";
int clientnumber=0;
int currentclient=0;
int lastclient=0;
#define DEFAULT_BUFLEN 512
#define DEFAULT_PORT "10150"
struct _client
{
bool con;
sockaddr_in addr; //Client info like ip address
SOCKET cs; //Client socket
fd_set set; //used to check if there is data in the socket
std::string ip;
std::string name;
int i; //any piece of additional info
} client[100];
WSADATA wsaData;
int iResult;
SOCKET ListenSocket = INVALID_SOCKET;
SOCKET ClientSocket = INVALID_SOCKET;
struct addrinfo *result = NULL;
struct addrinfo hints;
int iSendResult;
char recvbuf[DEFAULT_BUFLEN];
int recvbuflen = DEFAULT_BUFLEN;
DWORD WINAPI recvfunc(LPVOID randparam)
{
while (true) {
ClientSocket=client[currentclient].cs;
if (mrecv(true)=="1") {
client[currentclient].con=false;
ClientSocket=client[lastclient].cs;
break;
}
}
return 0;
}
DWORD WINAPI headerfunc(LPVOID randparam)
{
Sleep(500);
while (true) {
CONSOLE_SCREEN_BUFFER_INFO SBInfo;
HANDLE hOut = GetStdHandle(STD_OUTPUT_HANDLE);
GetConsoleScreenBufferInfo(hOut, &SBInfo);
int xx = SBInfo.dwCursorPosition.X;
int yy = SBInfo.dwCursorPosition.Y;
GoToXY(0,0);
HANDLE hHeaderColor;
hHeaderColor = GetStdHandle(STD_OUTPUT_HANDLE);
SetConsoleTextAttribute(hHeaderColor, FOREGROUND_GREEN);
std::cout<<"Server Started. Current Client:"<<currentclient<<" Clients connected: "<<clientnumber<<" ("<<xx<<","<<yy<<") "<<lastclient;
SetConsoleTextAttribute(hHeaderColor, 0 |
FOREGROUND_RED |
FOREGROUND_GREEN |
FOREGROUND_BLUE);
GoToXY(xx,yy);
Sleep(2000);
}
return 0;
}
DWORD WINAPI sendfunc(LPVOID randparam)
{
while (true) {
char mmessage[512];
std::cin.getline(mmessage, 512);
if (strlen(mmessage)<2) {
GoToXY(0,23);
sendfunc("1");
}
char msendbuf[512]="Server> ";
strcat(msendbuf,mmessage);
if (msend(msendbuf)==1) {
"Client must have disconnected. Please select a new client.";
sendfunc("1");
}
if ((strncmp(msendbuf,"Server> /",9)) != 0) {
printm(msendbuf,FOREGROUND_INTENSITY);
}
GoToXY(0,23);
for (int sp=0; sp<72; sp++) {
std::cout<<" ";
}
GoToXY(0,23);
}
return 0;
}
int APIENTRY WinMain(HINSTANCE hInstance, HINSTANCE hPrevInstance, LPTSTR lpCmdLine, int nCmdShow)
{
minitialize();
HANDLE hRecvThread;
HANDLE hSendThread;
HANDLE hHeaderThread;
DWORD dwRecvThreadId;
DWORD dwSendThreadId;
DWORD dwHeaderThreadId;
hHeaderThread = CreateThread(NULL,0,headerfunc,"1",0,&dwHeaderThreadId);
for (int mf=2; mf<25; mf++) {
std::cout<<"\n";
}
hSendThread = CreateThread(NULL,0,sendfunc,"1",0,&dwSendThreadId);
// Accept a client socket
for (int sock=1; sock<100; sock++) {
ClientSocket = accept(ListenSocket, NULL, NULL);
char sockprint[80];
char sockchar[4];
itoa(sock,sockchar,10);
strcpy(sockprint,"Client ");
strcat(sockprint,sockchar);
strcat(sockprint," connected.");
printm(sockprint);
GoToXY(0,23);
if (ClientSocket == INVALID_SOCKET) {
printm("accept failed with error: %d\n", WSAGetLastError());
closesocket(ListenSocket);
WSACleanup();
return 1;
}
client[sock].cs=ClientSocket;
client[sock].con=true;
lastclient=clientnumber;
clientnumber++;
currentclient=clientnumber;
hRecvThread = CreateThread(NULL,0,recvfunc,"1",0,&dwRecvThreadId);
}
// shutdown the connection since we're done
mshutdown();
std::cin.ignore();
return 0;
}
int printm(char *inp, DWORD color) {
HANDLE hOut;
hOut = GetStdHandle(STD_OUTPUT_HANDLE);
SetConsoleTextAttribute(hOut,
color);
printm(inp);
SetConsoleTextAttribute(hOut, 0 |
FOREGROUND_RED |
FOREGROUND_GREEN |
FOREGROUND_BLUE);
return 0;
}
int printm(char *inp) {
CONSOLE_SCREEN_BUFFER_INFO SBInfo;
HANDLE hOut = GetStdHandle(STD_OUTPUT_HANDLE);
GetConsoleScreenBufferInfo(hOut, &SBInfo);
int xx = SBInfo.dwCursorPosition.X;
int yy = SBInfo.dwCursorPosition.Y;
GoToXY(0,22);
std::cout<<inp<<"\n";
scroll();
GoToXY(xx,yy);
return 1;
}
int msend(char msendbuf[512]) // Send a message
{
if (strncmp(msendbuf,"Server> /exit",(strlen(msendbuf))) == 0) {
mexit();
}
if (strncmp(msendbuf,"Server> /set_client",19) == 0) {
int nm=atoi(&msendbuf[20]);
currentclient=nm;
ClientSocket=client[nm].cs;
char sockchar[4];
itoa(ClientSocket,sockchar,10);
char sockprint[80];
strcpy(sockprint,"New Socket: ");
strcat(sockprint,sockchar);
printm(sockprint);
char clientprint[80];
strcpy(clientprint,"Client: ");
strcat(clientprint,&msendbuf[20]);
printm(clientprint);
}
if (strncmp(msendbuf,"Server> /list_clients",(strlen(msendbuf))) == 0) {
printm("Clients:",FOREGROUND_RED);
for (int cm=1; cm < 100; cm++) {
int cn=client[cm].cs;
if (cn>0) {
char cli[80];
char cmchar[4];
char cnchar[80];
itoa(cn,cnchar,10);
itoa(cm,cmchar,10);
strcpy(cli,cmchar);
strcat(cli," ");
strcat(cli,cnchar);
strcat(cli," ");
strcat(cli,client[cm].ip.c_str());
strcat(cli," ");
strcat(cli,client[cm].name.c_str());
printm(cli,FOREGROUND_RED);
}
else {
break;
}
}
}
if (strncmp(msendbuf,"Server> /test",(strlen(msendbuf))) == 0) {
char ipcon[500];
*ipcon=(system("ipconfig"));
}
if (strncmp(msendbuf,"Server> /help",(strlen(msendbuf))) == 0) {
printm("Type /help for help or:");
printm("/set_client [client number]");
printm("/list_clients");
}
int iResult3 = send( ClientSocket, msendbuf, 512, 0 );
if (iResult3 == SOCKET_ERROR) {
printm("send failed with error: %d\n", WSAGetLastError());
return 1;
}
}
char* mrecv(bool show) //Recieve a message
{
int iResult2 = recv(ClientSocket, recvbuf, 512, 0);
if (iResult2 > 0) {
if ((strncmp(recvbuf,"/",1)) != 0) {
printm(recvbuf);
}
if (strncmp(recvbuf,"/ip",3) == 0) {
client[clientnumber].ip=&recvbuf[4];
char prin[80];
strcpy(prin,"client[clientnumber].ip: ");
strcat(prin,client[clientnumber].ip.c_str());
printm(prin,FOREGROUND_BLUE);
}
if (strncmp(recvbuf,"/name",5) == 0) {
client[clientnumber].name=&recvbuf[6];
char prin2[80];
strcpy(prin2,"client[clientnumber].name: ");
strcat(prin2,client[clientnumber].name.c_str());
printm(prin2,FOREGROUND_GREEN | FOREGROUND_BLUE);
}
if (strncmp(recvbuf,"/alert",5) == 0) {
char *message=&recvbuf[7];
char prin2[80];
strcpy(prin2,client[clientnumber].name.c_str());
strcat(prin2,": ");
strcat(prin2, message);
printm(prin2,FOREGROUND_RED);
}
if (strncmp(recvbuf,"Client> /alert",14) == 0) {
char *message=&recvbuf[15];
char prin2[80];
strcpy(prin2,client[clientnumber].name.c_str());
strcat(prin2,": ");
strcat(prin2, message);
printm(prin2,FOREGROUND_RED);
}
}
else if (iResult2 == 0) {
printf("Connection closing...\n");
closesocket(ClientSocket);
WSACleanup();
return "1";
}
else {
printm("recv failed with error: %d\n", WSAGetLastError());
printm("Client must have disconnected. Please select a new client.");
return "1";
}
return recvbuf;
}
int minitialize() //initialize the winsock server
{
// Initialize Winsock
iResult = WSAStartup(MAKEWORD(2,2), &wsaData);
if (iResult != 0) {
printm("WSAStartup failed with error: %d\n", iResult);
return 1;
}
ZeroMemory(&hints, sizeof(hints));
hints.ai_family = AF_INET;
hints.ai_socktype = SOCK_STREAM;
hints.ai_protocol = IPPROTO_TCP;
hints.ai_flags = AI_PASSIVE;
// Resolve the server address and port
iResult = getaddrinfo(NULL, DEFAULT_PORT, &hints, &result);
if ( iResult != 0 ) {
printm("getaddrinfo failed with error: %d\n", iResult);
WSACleanup();
return 1;
}
// Create a SOCKET for connecting to server
ListenSocket = socket(result->ai_family, result->ai_socktype, result->ai_protocol);
if (ListenSocket == INVALID_SOCKET) {
printm("socket failed with error: %ld\n", WSAGetLastError());
freeaddrinfo(result);
WSACleanup();
return 1;
}
// Setup the TCP listening socket
iResult = bind( ListenSocket, result->ai_addr, (int)result->ai_addrlen);
if (iResult == SOCKET_ERROR) {
printm("bind failed with error: %d\n", WSAGetLastError());
freeaddrinfo(result);
closesocket(ListenSocket);
WSACleanup();
return 1;
}
freeaddrinfo(result);
iResult = listen(ListenSocket, SOMAXCONN);
if (iResult == SOCKET_ERROR) {
printm("listen failed with error: %d\n", WSAGetLastError());
closesocket(ListenSocket);
WSACleanup();
return 1;
}
unsigned long b=1;
ioctlsocket(ClientSocket,FIONBIO,&b);
}
int mshutdown() //shutdown the server
{
iResult = shutdown(ClientSocket, SD_SEND);
if (iResult == SOCKET_ERROR) {
printm("shutdown failed with error: %d\n", WSAGetLastError());
closesocket(ClientSocket);
WSACleanup();
return 1;
}
// cleanup
closesocket(ClientSocket);
WSACleanup();
return 0;
}
void GoToXY(int column, int line)
{
// Create a COORD structure and fill in its members.
// This specifies the new position of the cursor that we will set.
COORD coord;
coord.X = column;
coord.Y = line;
// Obtain a handle to the console screen buffer.
// (You're just using the standard console, so you can use STD_OUTPUT_HANDLE
// in conjunction with the GetStdHandle() to retrieve the handle.)
// Note that because it is a standard handle, we don't need to close it.
HANDLE hConsole = GetStdHandle(STD_OUTPUT_HANDLE);
// Finally, call the SetConsoleCursorPosition function.
if (!SetConsoleCursorPosition(hConsole, coord))
{
// Uh-oh! The function call failed, so you need to handle the error.
// You can call GetLastError() to get a more specific error code.
// ...
return;
}
}
int scroll( void )
{
HANDLE hStdout;
CONSOLE_SCREEN_BUFFER_INFO csbiInfo;
SMALL_RECT srctScrollRect, srctClipRect;
CHAR_INFO chiFill;
COORD coordDest;
hStdout = GetStdHandle(STD_OUTPUT_HANDLE);
if (hStdout == INVALID_HANDLE_VALUE)
{
printf("GetStdHandle failed with %d\n", GetLastError());
return 1;
}
// Get the screen buffer size.
if (!GetConsoleScreenBufferInfo(hStdout, &csbiInfo))
{
printf("GetConsoleScreenBufferInfo failed %d\n", GetLastError());
return 1;
}
// The scrolling rectangle
srctScrollRect.Top = 1;
srctScrollRect.Bottom = 22;
srctScrollRect.Left = 0;
srctScrollRect.Right = csbiInfo.dwSize.X - 1;
// The destination for the scroll rectangle is one row up.
coordDest.X = 0;
coordDest.Y = 0;
// The clipping rectangle
srctClipRect.Top = 2;
srctClipRect.Bottom = 22;
srctClipRect.Left = 0;
srctClipRect.Right = csbiInfo.dwSize.X - 1;
// Fill the bottom row with blanks.
chiFill.Attributes = FOREGROUND_RED;
chiFill.Char.AsciiChar = (char)' ';
// Scroll up one line.
if(!ScrollConsoleScreenBuffer(
hStdout, // screen buffer handle
&srctScrollRect, // scrolling rectangle
&srctClipRect, // clipping rectangle
coordDest, // top left destination cell
&chiFill)) // fill character and color
{
printf("ScrollConsoleScreenBuffer failed %d\n", GetLastError());
return 1;
}
return 0;
}
int mexit()
{
msend("/server_closed");
mshutdown();
exit(0);
}
Turns out it was the recursive calling in my "sendfunc" thread that tripped me up.
Specifically,
if (msend(msendbuf)==1) {
"Client must have disconnected. Please select a new client.";
sendfunc("1");
}
Because I continued to call "sendfunc" from itself, it caused the stack overflow.
So, for anyone else having these problems, watch for overkill recursive function calls.
I simply removed my sending function and I was good to go.
The ConnectEx function requires an "unconnected, previously bound socket". Indeed, if I omit the bind step in my example (see below), ConnectEx fails with WSAEINVAL.
Here's my current understanding: before calling ConnectEx, bind the socket to INADDR_ANY and port 0 (unless it is already bound):
struct sockaddr_in addr;
ZeroMemory(&addr, sizeof(addr));
addr.sin_family = AF_INET;
addr.sin_addr.s_addr = INADDR_ANY;
addr.sin_port = 0;
rc = bind(sock, (SOCKADDR*) &addr, sizeof(addr));
if (rc != 0) { ... bind failed; call WSAGetLastError to see why ... }
Or for an IPv6 socket:
struct sockaddr_in6 addr;
ZeroMemory(&addr, sizeof(addr));
addr.sin6_family = AF_INET6;
addr.sin6_addr = in6addr_any;
addr.sin6_port = 0;
rc = bind(sock, (SOCKADDR*) &addr, sizeof(addr));
if (rc != 0) { ... bind failed; call WSAGetLastError to see why ... }
This lets the operating system assign a local address to our socket (as opposed to the remote address we are connecting to). connect does this step automatically, but ConnectEx does not.
My questions are:
Is my assessment correct?
Is there a way to do this automatic bind that is agnostic to the address family, or will I have to handle each of AF_INET, AF_INET6, AF_BTH (Bluetooth), etc. manually?
Working ConnectEx example (also on Gist: https://gist.github.com/4158972):
#include <stdio.h>
#include <WinSock2.h>
#include <MSWSock.h>
#include <WS2tcpip.h>
#pragma comment(lib, "Ws2_32.lib")
struct mswsock_s {
LPFN_CONNECTEX ConnectEx;
} mswsock;
static BOOL load_mswsock(void)
{
SOCKET sock;
DWORD dwBytes;
int rc;
/* Dummy socket needed for WSAIoctl */
sock = socket(AF_INET, SOCK_STREAM, 0);
if (sock == INVALID_SOCKET)
return FALSE;
{
GUID guid = WSAID_CONNECTEX;
rc = WSAIoctl(sock, SIO_GET_EXTENSION_FUNCTION_POINTER,
&guid, sizeof(guid),
&mswsock.ConnectEx, sizeof(mswsock.ConnectEx),
&dwBytes, NULL, NULL);
if (rc != 0)
return FALSE;
}
rc = closesocket(sock);
if (rc != 0)
return FALSE;
return TRUE;
}
int main(int argc, char *argv[])
{
int rc;
BOOL ok;
WSADATA wsaData;
SOCKET sock;
rc = WSAStartup(MAKEWORD(2,2), &wsaData);
if (rc != 0) {
printf("WSAStartup failed: %d\n", rc);
return 1;
}
if (LOBYTE(wsaData.wVersion) != 2 || HIBYTE(wsaData.wVersion) != 2) {
printf("Your computer is from the wrong millenium.\n");
WSACleanup();
return 1;
}
if (!load_mswsock()) {
printf("Error loading mswsock functions: %d\n", WSAGetLastError());
return 1;
}
sock = socket(AF_INET, SOCK_STREAM, 0);
if (sock == INVALID_SOCKET) {
printf("socket: %d\n", WSAGetLastError());
return 1;
}
/* ConnectEx requires the socket to be initially bound. */
{
struct sockaddr_in addr;
ZeroMemory(&addr, sizeof(addr));
addr.sin_family = AF_INET;
addr.sin_addr.s_addr = INADDR_ANY;
addr.sin_port = 0;
rc = bind(sock, (SOCKADDR*) &addr, sizeof(addr));
if (rc != 0) {
printf("bind failed: %d\n", WSAGetLastError());
return 1;
}
}
/* Issue ConnectEx and wait for the operation to complete. */
{
OVERLAPPED ol;
ZeroMemory(&ol, sizeof(ol));
sockaddr_in addr;
ZeroMemory(&addr, sizeof(addr));
addr.sin_family = AF_INET;
addr.sin_addr.s_addr = inet_addr("173.194.37.36"); // google.com
addr.sin_port = htons(80);
ok = mswsock.ConnectEx(sock, (SOCKADDR*) &addr, sizeof(addr), NULL, 0, NULL, &ol);
if (ok) {
printf("ConnectEx succeeded immediately\n");
} else if (WSAGetLastError() == ERROR_IO_PENDING) {
printf("ConnectEx pending\n");
DWORD numBytes;
ok = GetOverlappedResult((HANDLE) sock, &ol, &numBytes, TRUE);
if (ok)
printf("ConnectEx succeeded\n");
else
printf("ConnectEx failed: %d\n", WSAGetLastError());
} else {
printf("ConnectEx failed: %d\n", WSAGetLastError());
return 1;
}
}
/* Make the socket more well-behaved. */
rc = setsockopt(sock, SOL_SOCKET, SO_UPDATE_CONNECT_CONTEXT, NULL, 0);
if (rc != 0) {
printf("SO_UPDATE_CONNECT_CONTEXT failed: %d\n", WSAGetLastError());
return 1;
}
/* This will fail if SO_UPDATE_CONNECT_CONTEXT was not performed. */
rc = shutdown(sock, SD_BOTH);
if (rc != 0) {
printf("shutdown failed: %d\n", WSAGetLastError());
return 1;
}
printf("Done\n");
return 0;
}
connect does this step automatically, but ConnectEx does not.
Correct.
Is my assessment correct?
Yes.
Is there a way to do this automatic bind that is agnostic to the address family, or will I have to handle each of AF_INET, AF_INET6, AF_BTH (Bluetooth), etc. manually?
I believe that INADDR_ANY is a bunch of zeros in all address families, so you could just try using the memset() and omitting the assignment to addr.sin_addr.s_addr completely. Whether this is kosher, portable, politically correct etc. is another question into which I will not enter.
It seems pretty curious that Microsoft didn't manage to have ConnectEx() call bind() internally, considering that saving system calls is the motivation for its existence, and also considering that most programs never bind an outbound socket at all.
It is possible to get the bind address for ConnectEx in an address family independent way.
Solution 1
Call getaddrinfo with the following options:
pServiceName = "0"
hints.ai_flags = AI_PASSIVE
hints.ai_family = address family of the socket
Then use the first result of the returned address list.
To get the address family of the socket you can use getsockopt with SO_PROTOCOL_INFOW.
Solution 2
Use SOCKADDR_STORAGE for the address structure and call INETADDR_SETANY which is defined in MSTcpIP.h. It supports AF_INET and AF_INET6.
Hey there StackOverflow people!
I'm making an IOCP server and I have ironed out most issues so far but one still remain and I do not know where to start looking at. When I run the client/server on my machine everything is fine and dandy. It matches the speed of the Windows SDK Sample maybe a little bit faster and definitely uses less CPU cycle. However when I run the client from a separate computer, transfer speed caps at 37 KB/s and has a roundtrip latency of 200ms (as opposed to 0). Now if I connect the client to the SDK Sample server, I don't have that problem so there is something wrong with my code. As far as I know, the sockets are initialized the exact same way with the same options. I have also ran my server in a profiler to check for bottleneck but I couldn't find any. Also, the computers I have tried it on were connected to the same gigabit switch (with gigabit adapter). I know this is kind of vague but that's because I couldn't pinpoint the problem so far and I would be eternally grateful if any of you guys could point me in the right direction.
Cheers,
-Roxy
EDIT2:
After following Mike's advise, I did some research on the code and found out that when a remote client connects to the server most of the time the code is waiting on GetQueuedCompletionStatus. This suggest that IO request are simply taking a long time to complete but I still don't understand why. This only occurs only when the client is on a remote computer. I'm thinking this has something to do with how a setup the sockets or how I'm posting the request but I don't see any difference with the sample code.
Any ideas?
EDIT (Added sample code):
Alright, here it is! It ain't pretty though!
If you have the Windows SDK installed, you can connect to it using the iocpclient sample (Program Files\Microsoft SDKs\Windows\v7.1\Samples\netds\winsock\iocp\client) and changing it's default port at line 73 to 5000.
Weird things I've just noticed when trying it myself is that it seems the sample iocpclient doesn't cause the same caps at 37KB/s issue... However it looks like the sample code has a limit set to around 800KB/s. I'll post a client if that can be of any help.
#pragma comment(lib, "Ws2_32.lib")
#include <WinSock2.h>
#include <stdio.h>
unsigned int connection = 0;
unsigned int upload = 0;
unsigned int download = 0;
#define IO_CONTEXT_COUNT 5
class NetClientHost
{
friend class gNetProtocolHost;
public:
enum Operation
{
kOperationUnknown,
kOperationRead,
kOperationWrite,
};
struct ClientData
{
SOCKET socket;
};
struct IOContext
{
WSAOVERLAPPED overlapped;
WSABUF wsaReceiveBuf;
WSABUF wsaSendBuf;
char *buf;
char *TESTbuf;
unsigned long bytesReceived;
unsigned long bytesSent;
unsigned long flags;
unsigned int bytesToSendTotal;
unsigned int remainingBytesToSend;
unsigned int chunk;
Operation operation;
};
NetClientHost()
{
memset((void *) &m_clientData, 0, sizeof(m_clientData));
}
NetClientHost::IOContext *NetClientHost::AcquireContext()
{
while (true)
{
for (int i = 0; i < IO_CONTEXT_COUNT; ++i)
{
if (!(m_ioContexts + i)->inUse)
{
InterlockedIncrement(&(m_ioContexts + i)->inUse);
//ResetEvent(*(m_hContextEvents + i));
if ((m_ioContexts + i)->ioContext.TESTbuf == 0)
Sleep(1);
return &(m_ioContexts + i)->ioContext;
}
}
//++g_blockOnPool;
//WaitForMultipleObjects(IO_CONTEXT_COUNT, m_hContextEvents, FALSE, INFINITE);
}
}
const ClientData *NetClientHost::GetClientData() const
{
return &m_clientData;
};
void NetClientHost::Init(unsigned int bufferSize)
{
_InitializeIOContexts(bufferSize ? bufferSize : 1024);
}
void NetClientHost::ReleaseContext(IOContext *ioContext)
{
int i = sizeof(_IOContextData), j = sizeof(IOContext);
_IOContextData *contextData = (_IOContextData *) (((char *) ioContext) - (i - j));
InterlockedDecrement(&contextData->inUse);
//SetEvent(*(m_hContextEvents + contextData->index));
}
struct _IOContextData
{
unsigned int index;
volatile long inUse;
IOContext ioContext;
};
ClientData m_clientData;
_IOContextData *m_ioContexts;
HANDLE *m_hContextEvents;
void _InitializeIOContexts(unsigned int bufferSize)
{
m_ioContexts = new _IOContextData[IO_CONTEXT_COUNT];
m_hContextEvents = new HANDLE[IO_CONTEXT_COUNT];
memset((void *) m_ioContexts, 0, sizeof(_IOContextData) * IO_CONTEXT_COUNT);
for (int i = 0; i < IO_CONTEXT_COUNT; ++i)
{
(m_ioContexts + i)->index = i;
(m_ioContexts + i)->ioContext.buf = new char[bufferSize];
(m_ioContexts + i)->ioContext.wsaReceiveBuf.len = bufferSize;
(m_ioContexts + i)->ioContext.wsaReceiveBuf.buf = (m_ioContexts + i)->ioContext.buf;
(m_ioContexts + i)->ioContext.TESTbuf = new char[10000];
(m_ioContexts + i)->ioContext.wsaSendBuf.buf = (m_ioContexts + i)->ioContext.TESTbuf;
*(m_hContextEvents + i) = CreateEvent(0, TRUE, FALSE, 0);
}
}
void _SetSocket(SOCKET socket)
{
m_clientData.socket = socket;
}
};
bool WriteChunk(const NetClientHost *clientHost, NetClientHost::IOContext *ioContext)
{
int status;
status = WSASend(clientHost->GetClientData()->socket, &ioContext->wsaSendBuf, 1, &ioContext->bytesSent, ioContext->flags, &ioContext->overlapped, 0);
if (status == SOCKET_ERROR && WSAGetLastError() != WSA_IO_PENDING)
{
// ...
return false;
}
return true;
}
bool Write(NetClientHost *clientHost, void *buffer, unsigned int size, unsigned int chunk)
{
//__ASSERT(m_clientHost);
//__ASSERT(m_clientHost->GetClientData()->remainingBytesToSend == 0);
NetClientHost::IOContext *ioContext = clientHost->AcquireContext();
if (!chunk)
chunk = size;
ioContext->wsaSendBuf.buf = ioContext->TESTbuf;
ioContext->operation = NetClientHost::kOperationWrite;
ioContext->flags = 0;
ioContext->wsaSendBuf.buf = new char[size];
memcpy((void *) ioContext->wsaSendBuf.buf, buffer, chunk);
ioContext->wsaSendBuf.len = chunk;
ioContext->chunk = chunk;
ioContext->bytesToSendTotal = size;
ioContext->remainingBytesToSend = size;
return WriteChunk(clientHost, ioContext);
}
void Read(NetClientHost *clientHost)
{
NetClientHost::IOContext *ioContext = clientHost->AcquireContext();
int status;
memset((void *) ioContext, 0, sizeof(NetClientHost::IOContext));
ioContext->buf = new char[1024];
ioContext->wsaReceiveBuf.len = 1024;
ioContext->wsaReceiveBuf.buf = ioContext->buf;
ioContext->flags = 0;
ioContext->operation = NetClientHost::kOperationRead;
status = WSARecv(clientHost->GetClientData()->socket, &ioContext->wsaReceiveBuf, 1, &ioContext->bytesReceived, &ioContext->flags, &ioContext->overlapped, 0);
int i = WSAGetLastError();
if (status == SOCKET_ERROR && WSAGetLastError() != WSA_IO_PENDING)
{
// ...
}
}
bool AddSocket(HANDLE hIOCP, SOCKET socket)
{
++connection;
int bufSize = 0;
LINGER lingerStruct;
lingerStruct.l_onoff = 1;
lingerStruct.l_linger = 0;
setsockopt(socket, SOL_SOCKET, SO_SNDBUF, (char *) &bufSize, sizeof(int));
setsockopt(socket, SOL_SOCKET, SO_RCVBUF, (char *) &bufSize, sizeof(int));
setsockopt(socket, SOL_SOCKET, SO_LINGER, (char *) &lingerStruct, sizeof(lingerStruct) );
NetClientHost *clientHost = new NetClientHost;
clientHost->_InitializeIOContexts(1024);
clientHost->Init(0);
clientHost->_SetSocket(socket);
// Add this socket to the IO Completion Port
CreateIoCompletionPort((HANDLE) socket, hIOCP, (DWORD_PTR) clientHost, 0);
Read(clientHost);
return true;
}
int read = 0, write = 0;
DWORD WINAPI WorkerThread(LPVOID param)
{
LPOVERLAPPED overlapped;
NetClientHost *clientHost;
HANDLE hIOCP = (HANDLE) param;
DWORD ioSize;
BOOL status;
while (true)
{
status = GetQueuedCompletionStatus(hIOCP, &ioSize, (PULONG_PTR) &clientHost, (LPOVERLAPPED *) &overlapped, INFINITE);
if (!(status || ioSize))
{
--connection;
//_CloseConnection(clientHost);
continue;
}
NetClientHost::IOContext *ioContext = (NetClientHost::IOContext *) overlapped;
switch (ioContext->operation)
{
case NetClientHost::kOperationRead:
download += ioSize;
Write(clientHost, ioContext->wsaReceiveBuf.buf, ioSize, 0);
write++;
clientHost->ReleaseContext(ioContext);
break;
case NetClientHost::kOperationWrite:
upload += ioSize;
if (ioContext->remainingBytesToSend)
{
ioContext->remainingBytesToSend -= ioSize;
ioContext->wsaSendBuf.len = ioContext->chunk <= ioContext->remainingBytesToSend ? ioContext->chunk : ioContext->remainingBytesToSend; // equivalent to min(clientData->chunk, clientData->remainingBytesToSend);
ioContext->wsaSendBuf.buf += ioContext->wsaSendBuf.len;
}
if (ioContext->remainingBytesToSend)
{
WriteChunk(clientHost, ioContext);
}
else
{
clientHost->ReleaseContext(ioContext);
Read(clientHost);
read++;
}
break;
}
}
return 0;
}
DWORD WINAPI ListenThread(LPVOID param)
{
SOCKET sdListen = (SOCKET) param;
HANDLE hIOCP = CreateIoCompletionPort(INVALID_HANDLE_VALUE, 0, 0, 0);
CreateThread(0, 0, WorkerThread, hIOCP, 0, 0);
CreateThread(0, 0, WorkerThread, hIOCP, 0, 0);
CreateThread(0, 0, WorkerThread, hIOCP, 0, 0);
CreateThread(0, 0, WorkerThread, hIOCP, 0, 0);
while (true)
{
SOCKET as = WSAAccept(sdListen, 0, 0, 0, 0);
if (as != INVALID_SOCKET)
AddSocket(hIOCP, as);
}
}
int main()
{
SOCKET sdListen;
SOCKADDR_IN si_addrlocal;
int nRet;
int nZero = 0;
LINGER lingerStruct;
WSADATA wsaData;
WSAStartup(0x202, &wsaData);
sdListen = WSASocket(AF_INET, SOCK_STREAM, IPPROTO_IP, NULL, 0, WSA_FLAG_OVERLAPPED);
si_addrlocal.sin_family = AF_INET;
si_addrlocal.sin_port = htons(5000);
si_addrlocal.sin_addr.s_addr = htonl(INADDR_ANY);
nRet = bind(sdListen, (struct sockaddr *)&si_addrlocal, sizeof(si_addrlocal));
nRet = listen(sdListen, 5);
nZero = 0;
nRet = setsockopt(sdListen, SOL_SOCKET, SO_SNDBUF, (char *) &nZero, sizeof(nZero));
nZero = 0;
nRet = setsockopt(sdListen, SOL_SOCKET, SO_RCVBUF, (char *)&nZero, sizeof(nZero));
lingerStruct.l_onoff = 1;
lingerStruct.l_linger = 0;
nRet = setsockopt(sdListen, SOL_SOCKET, SO_LINGER, (char *)&lingerStruct, sizeof(lingerStruct) );
CreateThread(0, 0, ListenThread, (LPVOID) sdListen, 0, 0);
HANDLE console = GetStdHandle(STD_OUTPUT_HANDLE);
while (true)
{
COORD c = {0};
SetConsoleCursorPosition(console, c);
printf("Connections: %i \nUpload: %iKB/s \nDownload: %iKB/s ", connection, upload * 2 / 1024, download * 2 / 1024);
upload = 0;
download = 0;
Sleep(500);
}
return 0;
}
This kind of asynchronous system should be able to run at full datalink speed. Problems I've found wrong are such as:
timeout settings causing needless retransmissions
in the receiving process, received message A might trigger a database update, such that received message B has to wait, causing an unnecessary delay in the response to message B back to the sender, when the DB update could actually be done in idle time.
There's something called wireshark that can give you some visibility into the message traffic.
I used to do it the hard way, with time-stamped message logs.
BTW: I would first use this method on the individual processes, to clean out any bottlenecks, before doing the asynchronous analysis. If you haven't done this, you can bet they're in there.
Just any old profiler isn't reliable. There are good ones, including Zoom.