Re: [Qemu-devel] [PATCH v3 1/3] Refactor inet_connect_opts function

[Markus Armbruster]

Amos Kong <address@hidden> writes:

> On 19/09/12 16:33, Amos Kong wrote:
>> On 14/09/12 02:58, Orit Wasserman wrote:
>>> From: "Michael S. Tsirkin" <address@hidden>
>>>
>>> refactor address resolution code to fix nonblocking connect
>>> remove getnameinfo call
>>>
>>> Signed-off-by: Michael S. Tsirkin <address@hidden>
>>> Signed-off-by: Amos Kong <address@hidden>
>>> Signed-off-by: Orit Wasserman <address@hidden>
>>
>> Hi Orit,
>>
>> Happy new year!
>>
>>> ---
>>>   qemu-sockets.c |  144
>>> +++++++++++++++++++++++++++++++------------------------
>>>   1 files changed, 81 insertions(+), 63 deletions(-)
>>>
>>> diff --git a/qemu-sockets.c b/qemu-sockets.c
>>> index 361d890..939a453 100644
>>> --- a/qemu-sockets.c
>>> +++ b/qemu-sockets.c
>>> @@ -209,95 +209,113 @@ listen:
>>>      return slisten;
>>>  }
>>>
>>> -int inet_connect_opts(QemuOpts *opts, bool *in_progress, Error **errp)
>>> +#ifdef _WIN32
>>> +#define QEMU_SOCKET_RC_INPROGRESS(rc) \
>>> +    ((rc) == -EINPROGRESS || rc == -EWOULDBLOCK || rc == -WSAEALREADY)
>
> ^^ Brackets are only be used for first 'rc'
>
>>> +#else
>>> +#define QEMU_SOCKET_RC_INPROGRESS(rc) \
>>> +    ((rc) == -EINPROGRESS)
>>> +#endif
>
>>
>>> +
>>> +int inet_connect_opts(QemuOpts *opts, bool *in_progress, Error **errp)
>>> +{
>>> +    struct addrinfo *res, *e;
>>> +    int sock = -1;
>>> +    bool block = qemu_opt_get_bool(opts, "block", 0);
>>> +
>>> +    res = inet_parse_connect_opts(opts, errp);
>>> +    if (!res) {
>>> +        return -1;
>
> In this error path, in_progress is not assigned, but it's used
> in tcp_start_outgoing_migration()

Took me a minute to see what you mean.

inet_connect_opts() is called by inet_connect(), which is called by
tcp_start_outgoing_migration(), which uses in_progress.

The other callers of inet_connect() and inet_connect_opts() aren't
affected, because they pass null in_progress.

> Let also set the default value of in_progress to 'false' in
> tcp_start_outgoing_migration()

No, let's make sure the functions that take an in_progress argument
always set it.  That's easier to use safely.

>>> +    }
>>> +
>>
>>> +    if (in_progress) {
>>> +        *in_progress = false;
>>>       }
>>
>> trivial comment:
>>
>> You moved this block to head of inet_connect_addr() in [patch 3/3],
>> why not do this in this patch?
>>
>> I know if *in_progress becomes "true", sock is always >= 0, for loop
>> will exits.
>> But moving this block to inet_connect_addr() is clearer.

Makes inet_connect_addr() always set in_progress, which I like.

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