changing a program to become a service? - c++

Question

i want to create a application that can run as a service and also another program (in c++) that can communicate with it. Basically i want the program to send messages to the service and the service just echoes them back to the program
sample output of program would be something like this:
Please input your message: hello
Receive response from server: hello
i have a very simple client server program in UDP that does this - server echoes back the messages the clients sends. so my question is can i change the server to become a service and change the client so it still communicates with the service? and if so how is this done?
i have never used code to create a service before so if someone can link any tutorials that would be great
heres the program i want to change:
server
void InitWinsock()
{
WSADATA wsaData;
WSAStartup(MAKEWORD(2, 2), &wsaData);
}
int _tmain(int argc, _TCHAR* argv[])
{
SOCKET socketS;
InitWinsock();
struct sockaddr_in local;
struct sockaddr_in from;
int fromlen = sizeof(from);
local.sin_family = AF_INET;
local.sin_port = htons(1234);
local.sin_addr.s_addr = INADDR_ANY;
socketS = socket(AF_INET,SOCK_DGRAM,0);
bind(socketS,(sockaddr*)&local,sizeof(local));
while (1)
{
char buffer[1024];
ZeroMemory(buffer, sizeof(buffer));
printf("Waiting...\n");
if (recvfrom(socketS,buffer,sizeof(buffer),0,(sockaddr*)&from,&fromlen)!=SOCKET_ERROR)
{
printf("Received message from %s: %s\n",inet_ntoa(from.sin_addr), buffer);
sendto(socketS, buffer, sizeof(buffer), 0, (sockaddr*)&from, fromlen);
}
Sleep(500);
}
closesocket(socketS);
return 0;
}
client:
void InitWinsock()
{
WSADATA wsaData;
WSAStartup(MAKEWORD(2, 2), &wsaData);
}
int _tmain(int argc, _TCHAR* argv[])
{
SOCKET socketC;
InitWinsock();
struct sockaddr_in serverInfo;
int len = sizeof(serverInfo);
serverInfo.sin_family = AF_INET;
serverInfo.sin_port = htons(1234);
serverInfo.sin_addr.s_addr = inet_addr("127.0.0.1");
socketC = socket(AF_INET,SOCK_DGRAM,0);
while (1)
{
char buffer[1024];
ZeroMemory(buffer, sizeof(buffer));
printf("Please input your message: ");
scanf("%s", buffer);
if (strcmp(buffer,"exit") == 0)
break;
if (sendto(socketC, buffer, sizeof(buffer), 0, (sockaddr*)&serverInfo, len) != SOCKET_ERROR)
{
if (recvfrom(socketC, buffer, sizeof(buffer), 0, (sockaddr*)&serverInfo, &len) != SOCKET_ERROR)
{
printf("Receive response from server: %s\n", buffer);
}
}
}
closesocket(socketC);
return 0;
}

Answer 1

Use service example as sergmat said. Use the code in Svp.cpp, and put it into your server. Update the SVCNAME to your service name. Take the code in your _tmain and put it into the bottom of SvcInit where the TO_DO: Perform work until service stops is. Take out the while loop below it.
As an aside, your server has a Sleep(500) in the main loop. That's unnecessary as the server will block on the recv anyway.
To terminate the service, instead of using the ghSvcStopEvent, I'd just make the socket handle and some closing flag global, then set the flag and close the socket when you get the SERVICE_CONTROL_STOP signal.
You'll have a few more cleanup details but that should more than get you started...

Answer 2

Forget about changing your code, just use srvany.