Re: Is errno handling correct for Windows?

[Eric Curtin <ericcurtin17@xxxxxxxxx>]

Recently I had quite a bit of trouble with libssh as the client and
freesshd as the server. I was tunneling RDC through that. But it worked
fine with cygwin openssh 7.7 as the server in place of freesshd for me at
least 😊

Putty also had this issue with freesshd and RDC.

On Wed 2 May 2018, 20:53 Jan Krause, <voltamund@xxxxxxxxx> wrote:

> Hello
>
> Is libssh really supported on Windows (without using cygwin or MinGW)?
> From the cmake files and the source code it looks like Windows is a
> supported Platform. I could build recent sources from master for Windows 7
> and Windows CE 6. For Windows CE 6 there was a bit of additional work
> required. With both versions I could successfully run the sftp example.
>
> But when I look at the source code in libssh I am not sure if the errno
> handling is correctly done for Windows.
>
> For example in ssh_connect_host_nonblocking there is:
>     errno = 0;
>     rc = connect(s, itr->ai_addr, itr->ai_addrlen);
>     if (rc == -1 && (errno != 0) && (errno != EINPROGRESS)) {
>       ssh_set_error(session, SSH_FATAL,
>           "Failed to connect: %s", strerror(errno));
>       ssh_connect_socket_close(s);
>       s = -1;
>       continue;
>     }
>
> The if condition will never be true on Windows, even if connect returns -1
> and WSAGetLastError would return something different from WSAEWOULDBLOCK.
> Is it supposed to work like this?
>
> or in bsd_poll
>     #ifdef _WIN32
>             if ((ret == -1) &&
>                 (errno == WSAESHUTDOWN || errno == WSAECONNRESET ||
>                  errno == WSAECONNABORTED || errno == WSAENETRESET)) {
>     #else
>
>
> The Windows Sockets API does not set errno.
>
> https://msdn.microsoft.com/en-us/library/windows/desktop/ms737828(v=vs.85).aspx
>
>
> Other code uses WSAGetLastError (socket.c) as I would expect.
>
>
>
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