[libvirt] [PATCH 03/15] Introduce a generic object for using network sockets

[Wen Congyang]

At 12/16/2010 07:21 PM, Daniel P. Berrange Write:
> Introduces a simple wrapper around the raw POSIX sockets APIs
> and name resolution APIs. Allows for easy creation of client
> and server sockets with correct usage of name resolution APIs
> for protocol agnostic socket setup.
> 
> It can listen for UNIX and TCP stream sockets.
> 
> It can connect to UNIX, TCP streams directly, or indirectly
> to UNIX sockets via an SSH tunnel or external command
> 
> * src/Makefile.am: Add to libvirt-net-rpc.la
> * src/rpc/virnetsocket.c, src/rpc/virnetsocket.h: Generic
>   sockets APIs
> ---
>  .x-sc_avoid_write      |    1 +
>  po/POTFILES.in         |    1 +
>  src/Makefile.am        |    3 +-
>  src/rpc/virnetsocket.c |  723 ++++++++++++++++++++++++++++++++++++++++++++++++
>  src/rpc/virnetsocket.h |  100 +++++++
>  5 files changed, 827 insertions(+), 1 deletions(-)
>  create mode 100644 src/rpc/virnetsocket.c
>  create mode 100644 src/rpc/virnetsocket.h
> 

<snip>

> +static virNetSocketPtr virNetSocketNew(virSocketAddrPtr localAddr,
> +                                       virSocketAddrPtr remoteAddr,
> +                                       int fd, int errfd, pid_t pid)
> +{
> +    virNetSocketPtr sock;
> +    int no_slow_start = 1;
> +
> +    VIR_DEBUG("localAddr=%p remoteAddr=%p fd=%d errfd=%d pid=%d",
> +              localAddr, remoteAddr,
> +              fd, errfd, pid);
> +
> +    if (virSetCloseExec(fd) < 0 ||
> +        virSetNonBlock(fd) < 0)
> +        return NULL;
> +
> +    if (VIR_ALLOC(sock) < 0) {
> +        virReportOOMError();
> +        return NULL;
> +    }
> +
> +    sock->localAddr = *localAddr;

In the function virNetSocketNewConnectCommand():
    if (!(*retsock = virNetSocketNew(NULL, NULL, sv[0], errfd[0], pid)))
        goto error;
So we should check whether localAddr is NULL before dereferencing it.

> +    if (remoteAddr)
> +        sock->remoteAddr = *remoteAddr;
> +    sock->fd = fd;
> +    sock->errfd = errfd;
> +    sock->pid = pid;
> +
> +    /* Disable nagle */
> +    if (sock->localAddr.data.sa.sa_family != AF_UNIX)
> +        setsockopt (fd, IPPROTO_TCP, TCP_NODELAY,
> +                    (void *)&no_slow_start,
> +                    sizeof(no_slow_start));
> +
> +
> +    DEBUG("local family = %d remote family = %d",
> +          localAddr->data.sa.sa_family,
> +          remoteAddr ? remoteAddr->data.sa.sa_family : 0);
we should check localAddr

> +    if (!(sock->localAddrStr = virSocketFormatAddrFull(localAddr, true, ";")))
> +        goto error;
we should check localAddr
> +
> +    if (remoteAddr &&
> +        !(sock->remoteAddrStr = virSocketFormatAddrFull(remoteAddr, true, ";")))
> +        goto error;
> +
> +    sock->client = localAddr && !remoteAddr ? false : true;
> +
> +    VIR_DEBUG("sock=%p localAddrStr=%s remoteAddrStr=%s",
> +              sock, NULLSTR(sock->localAddrStr), NULLSTR(sock->remoteAddrStr));
> +
> +    return sock;
> +
> +error:
> +    virNetSocketFree(sock);
> +    return NULL;
> +}
> +
> +

<snip>

> +    virCommandSetInputFD(cmd, sv[1]);
> +    virCommandSetOutputFD(cmd, &sv[1]);
> +    virCommandSetOutputFD(cmd, &errfd[1]);
s/virCommandSetOutputFD/virCommandSetErrorFD/