[libvirt] [PATCH 3/4] remote: Print ssh stderr on connection failure

[Daniel P. Berrange]

On Fri, Feb 12, 2010 at 10:32:16AM -0500, Cole Robinson wrote:
> ---
>  src/remote/remote_driver.c |   37 ++++++++++++++++++++++++++++++++++---
>  1 files changed, 34 insertions(+), 3 deletions(-)
> 
> diff --git a/src/remote/remote_driver.c b/src/remote/remote_driver.c
> index 13534ce..7f92fd0 100644
> --- a/src/remote/remote_driver.c
> +++ b/src/remote/remote_driver.c
> @@ -154,6 +154,7 @@ struct private_data {
>      virMutex lock;
>  
>      int sock;                   /* Socket. */
> +    int errsock;                /* Socket connected to remote stderr */
>      int watch;                  /* File handle watch */
>      pid_t pid;                  /* PID of tunnel process */
>      int uses_tls;               /* TLS enabled on socket? */
> @@ -783,6 +784,7 @@ doRemoteOpen (virConnectPtr conn,
>      case trans_ext: {
>          pid_t pid;
>          int sv[2];
> +        int errsock[2];
>  
>          /* Fork off the external process.  Use socketpair to create a private
>           * (unnamed) Unix domain socket to the child process so we don't have
> @@ -794,14 +796,21 @@ doRemoteOpen (virConnectPtr conn,
>              goto failed;
>          }
>  
> +        if (socketpair (PF_UNIX, SOCK_STREAM, 0, errsock) == -1) {
> +            virReportSystemError(errno, "%s",
> +                                 _("unable to create socket pair"));
> +            goto failed;
> +        }

I think you just want pipe() here, since this does not want to
be a bi-directional channel.

> +
>          if (virExec((const char**)cmd_argv, NULL, NULL,
> -                    &pid, sv[1], &(sv[1]), NULL,
> +                    &pid, sv[1], &(sv[1]), &(errsock[1]),
>                      VIR_EXEC_CLEAR_CAPS) < 0)
>              goto failed;
>  
>          /* Parent continues here. */
>          close (sv[1]);
>          priv->sock = sv[0];
> +        priv->errsock = errsock[0];
>          priv->pid = pid;
>  
>          /* Do not set 'is_secure' flag since we can't guarentee
> @@ -827,6 +836,12 @@ doRemoteOpen (virConnectPtr conn,
>          goto failed;
>      }
>  
> +    if ((priv->errsock != -1) && virSetNonBlock(priv->errsock) < 0) {
> +        virReportSystemError(errno, "%s",
> +                             _("unable to make socket non-blocking"));
> +        goto failed;
> +    }
> +
>      if (pipe(wakeupFD) < 0) {
>          virReportSystemError(errno, "%s",
>                               _("unable to make pipe"));
> @@ -939,6 +954,9 @@ doRemoteOpen (virConnectPtr conn,
>  
>   failed:
>      /* Close the socket if we failed. */
> +    if (priv->errsock >= 0)
> +        close(priv->errsock);
> +
>      if (priv->sock >= 0) {
>          if (priv->uses_tls && priv->session) {
>              gnutls_bye (priv->session, GNUTLS_SHUT_RDWR);
> @@ -986,6 +1004,7 @@ remoteAllocPrivateData(virConnectPtr conn)
>      priv->localUses = 1;
>      priv->watch = -1;
>      priv->sock = -1;
> +    priv->errsock = -1;
>  
>      return priv;
>  }
> @@ -1408,6 +1427,7 @@ doRemoteClose (virConnectPtr conn, struct private_data *priv)
>          sasl_dispose (&priv->saslconn);
>  #endif
>      close (priv->sock);
> +    close (priv->errsock);
>  
>  #ifndef WIN32
>      if (priv->pid > 0) {
> @@ -7785,12 +7805,23 @@ remoteIOReadBuffer(virConnectPtr conn,
>                  if (errno == EWOULDBLOCK)
>                      return 0;
>  
> +                char errout[1024] = "\0";
> +                if (priv->errsock) {

Should be   priv->errsock != -1

> +                    recv(priv->errsock, errout, sizeof(errout), 0);
> +                }
> +
>                  virReportSystemError(errno,
> -                                     "%s", _("cannot recv data"));
> +                                     _("cannot recv data: %s"), errout);
> +
>              } else {
> +                char errout[1024] = "\0";
> +                if (priv->errsock) {

Likewise here

> +                    recv(priv->errsock, errout, sizeof(errout), 0);
> +                }
> +
>                  errorf (in_open ? NULL : conn,
>                          VIR_ERR_SYSTEM_ERROR,
> -                        "%s", _("server closed connection"));
> +                        _("server closed connection: %s"), errout);
>              }
>              return -1;
>          }
> -- 


Daniel
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