Re: [PATCH v4 3/8] migration: converts socket backend to accept MigrateAddress struct

[Het Gala <het.gala@nutanix.com>]

On 15/05/23 8:16 pm, Juan Quintela wrote:
> Het Gala <het.gala@nutanix.com> wrote:
>> On 15/05/23 3:47 pm, Daniel P. Berrangé wrote:
>>> On Fri, May 12, 2023 at 02:32:35PM +0000, Het Gala wrote:
>>>> Socket transport backend for 'migrate'/'migrate-incoming' QAPIs accept
>>>> new wire protocol of MigrateAddress struct.
>>>>
>>>> It is achived by parsing 'uri' string and storing migration parameters
>>>> required for socket connection into well defined SocketAddress struct.
>>>>
>>>> Suggested-by: Aravind Retnakaran <aravind.retnakaran@nutanix.com>
>>>> Signed-off-by: Het Gala <het.gala@nutanix.com>
>>>> ---
>>>>    migration/exec.c      |  4 ++--
>>>>    migration/exec.h      |  4 ++++
>>>>    migration/migration.c | 44 +++++++++++++++++++++++++++++++------------
>>>>    migration/socket.c    | 34 +++++----------------------------
>>>>    migration/socket.h    |  7 ++++---
>>>>    5 files changed, 47 insertions(+), 46 deletions(-)
>>>>
>>>> diff --git a/migration/exec.c b/migration/exec.c
>>>> index 2bf882bbe1..c4a3293246 100644
>>>> --- a/migration/exec.c
>>>> +++ b/migration/exec.c
>>>> @@ -27,7 +27,6 @@
>>>>    #include "qemu/cutils.h"
>>>>      #ifdef WIN32
>>>> -const char *exec_get_cmd_path(void);
>>>>    const char *exec_get_cmd_path(void)
>> Even this, I will shift it to the 2nd patch, where I need to move
>> exec_get_cmd_path() out accross other file (migration.c).
> great.
>
>>>>    {
>>>>        g_autofree char *detected_path = g_new(char, MAX_PATH);
>>>> @@ -40,7 +39,8 @@ const char *exec_get_cmd_path(void)
>>>>    }
>>>>    #endif
>>>>    -void exec_start_outgoing_migration(MigrationState *s, const char
>>>> *command, Error **errp)
>>>> +void exec_start_outgoing_migration(MigrationState *s, const char *command,
>>>> +                                   Error **errp)
>>>>    {
>>>>        QIOChannel *ioc;
>> Sure, Juan. Will change this in the 2nd patch itself instead of
>> here. I am not very convinved why should we have a different patch all
>> together for this, because we are just using this code outside this
>> file in my opinion? But if you still think so, I can make a different
>> patch for that.
> It is up to you.

For now, I will keep it with 2nd patch. If any other maintainer also 
thinks that it should be a separate patch all together of windows 
support for exec, I will make a new patch for that. But thankyou for 
your suggestion 😁

>> Juan, I get your point. But I think, we won't be needing local_err at
>> all, if I use g_autoptr for 'channel' and 'saddr' is a part of
>> 'channel'. Let me have a v2 patchset and if it is still not
>> convinving, we can have a discussion on this.
>>> THis leaks 'channel', and free's 'saddr' which actually  belongs
>>> to channel.
>>>
>>> With my comments on the previous patch suggesting g_autoptr for
>>> 'channel', we don't need any free calls for 'saddr' or 'channel'.
>> Right. With g_autoptr used for freeing 'channel' in last patch, we
>> wont have to worry about freeing 'saddr' at all. Thanks Daniel
>>
>> if (local_err) {
>>      qapi_free_SocketAddress(saddr);
>>      error_propagate(errp, local_err);
>>      return;
>> }
>> And after changing the position for assigning 'saddr' and using
>> g_autoptr for 'channel' I believe we can get rid of 'local_error'
>> variable too and replace it with 'errp'. Please suggest if I am
>> missing something here. TIA!
> great.  That is much better.
Ack.
>>>>    -void socket_start_outgoing_migration(MigrationState *s,
>>>> -                                     const char *str,
>>>> -                                     Error **errp)
>>>> -{
>>>> -    Error *err = NULL;
>>>> -    SocketAddress *saddr = socket_parse(str, &err);
>>>> -    if (!err) {
>>>> -        socket_start_outgoing_migration_internal(s, saddr, &err);
>>>> -    }
>>>> -    error_propagate(errp, err);
>>>> -}
>>>> -
>> Actually Juan. I don't need this function at all, because parsing of
>> uri into socketAddress using socket_parse is already done. So there is
>> no use of having this function in the first place, so I decided to
>> delete this fucntion all together. Same with incoming function.
> What I mean is that this code was already there.  And it was doing it
> wrong.  The parts that I corrected you were using this pattern, chcking
> that err was NULL, intsead of cheking that saddr is NULL.
Yes, I get your point. But that function is useless if socket_parse() 
function is not needed. So have omitted the function all together as 
socket parsing is already done in earlier patches.
> Later, Juan.
Regards,
Het Gala