[Spice-devel] [PATCH spice-server 06/33] sys-socket: Add socket_newpair utility

[Frediano Ziglio]

> 
> Hi
> 
> On Fri, Dec 21, 2018 at 4:03 PM Frediano Ziglio <fziglio at redhat.com> wrote:
> >
> > Allows to easier port socketpair.
> > Windows does not have this function, we need to create a pair
> > using 2 internet sockets and connecting one to the other.
> 
> Have you considered namedpipes instead?
> 

Yes, is true that sockets and kernel handles are in the same domain,
but I noted Qemu under Windows is expecting SOCKETs, maybe they could
accept HANDLEs too, I could test it.
One handle would go to Qemu, the other to GLib.
I have to try, maybe it was just easier for me that way.

At least for a quick way to communicate between Qemu and QXL thread
could be worth.

> 
> >
> > Signed-off-by: Frediano Ziglio <fziglio at redhat.com>
> > ---
> >  server/sys-socket.c | 75 +++++++++++++++++++++++++++++++++++++++++++++
> >  server/sys-socket.h |  7 +++++
> >  2 files changed, 82 insertions(+)
> >
> > diff --git a/server/sys-socket.c b/server/sys-socket.c
> > index 7ce5dab1..af2f0b83 100644
> > --- a/server/sys-socket.c
> > +++ b/server/sys-socket.c
> > @@ -209,4 +209,79 @@ SPICE_CONSTRUCTOR_FUNC(socket_win32_init)
> >      WSADATA wsaData;
> >      WSAStartup(MAKEWORD(2, 2), &wsaData);
> >  }
> > +
> > +int socket_newpair(int type, int protocol, socket_t sv[2])
> > +{
> > +    struct sockaddr_in sa, sa2;
> > +    socklen_t addrlen;
> > +    SOCKET s, pairs[2];
> > +
> > +    if (!sv) {
> > +        return -1;
> > +    }
> > +
> > +    /* create a listener */
> > +    s = socket(AF_INET, type, 0);
> > +    if (s == INVALID_SOCKET) {
> > +        return -1;
> > +    }
> > +
> > +    pairs[1] = INVALID_SOCKET;
> > +
> > +    pairs[0] = socket(AF_INET, type, 0);
> > +    if (pairs[0] == INVALID_SOCKET) {
> > +        goto cleanup;
> > +    }
> > +
> > +    /* bind to a random port */
> > +    sa.sin_family = AF_INET;
> > +    sa.sin_addr.s_addr = htonl(INADDR_LOOPBACK);
> > +    sa.sin_port = 0;
> > +    if (bind(s, (struct sockaddr*) &sa, sizeof(sa)) < 0) {
> > +        goto cleanup;
> > +    }
> > +    if (listen(s, 1) < 0) {
> > +        goto cleanup;
> > +    }
> > +
> > +    /* connect to kernel choosen port */
> > +    addrlen = sizeof(sa);
> > +    if (getsockname(s, (struct sockaddr*) &sa, &addrlen) < 0) {
> > +        goto cleanup;
> > +    }
> > +    if (connect(pairs[0], (struct sockaddr*) &sa, sizeof(sa)) < 0) {
> > +        goto cleanup;
> > +    }
> > +    addrlen = sizeof(sa2);
> > +    pairs[1] = accept(s, (struct sockaddr*) &sa2, &addrlen);
> > +    if (pairs[1] == INVALID_SOCKET) {
> > +        goto cleanup;
> > +    }
> > +
> > +    /* check proper connection */
> > +    addrlen = sizeof(sa);
> > +    if (getsockname(pairs[0], (struct sockaddr*) &sa, &addrlen) < 0) {
> > +        goto cleanup;
> > +    }
> > +    addrlen = sizeof(sa2);
> > +    if (getpeername(pairs[1], (struct sockaddr*) &sa2, &addrlen) < 0) {
> > +        goto cleanup;
> > +    }
> > +    if (sa.sin_family != sa2.sin_family || sa.sin_port != sa2.sin_port
> > +        || sa.sin_addr.s_addr != sa2.sin_addr.s_addr) {
> > +        goto cleanup;
> > +    }
> > +
> > +    closesocket(s);
> > +    sv[0] = SOCKET_FROM_INT(pairs[0]);
> > +    sv[1] = SOCKET_FROM_INT(pairs[1]);
> > +    return 0;
> > +
> > +cleanup:
> > +    socket_win32_set_errno();
> > +    closesocket(s);
> > +    closesocket(pairs[0]);
> > +    closesocket(pairs[1]);
> > +    return -1;
> > +}
> >  #endif
> > diff --git a/server/sys-socket.h b/server/sys-socket.h
> > index c21e9a69..9dca563b 100644
> > --- a/server/sys-socket.h
> > +++ b/server/sys-socket.h
> > @@ -56,6 +56,11 @@ static inline void socket_win32_set_errno(void)
> >  {
> >  }
> >
> > +static inline int socket_newpair(int type, int protocol, socket_t sv[2])
> > +{
> > +    return socketpair(AF_LOCAL, type, protocol, (int*) sv);
> > +}
> > +
> >  #define socket_read(sock, buf, len) read(socket_get_raw(sock), buf, len)
> >  #define socket_write(sock, buf, len) write(socket_get_raw(sock), buf, len)
> >  #define socket_writev(sock, iov, n) writev(socket_get_raw(sock), iov, n)
> > @@ -170,6 +175,8 @@ socket_listen(socket_t sock, int backlog)
> >      }
> >      return res;
> >  }
> > +
> > +int socket_newpair(int type, int protocol, socket_t sv[2]);
> >  #endif
> >
> >  // common part

Frediano