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Date: Wed, 12 Oct 2016 08:40:38 +0800
From: Changlong Xie <xiecl.fnst@cn.fujitsu.com>
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Subject: Re: [Qemu-devel] [PATCH v2 1/2] block/replication: prefect the
 logic to acquire 'top_id'
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To: Eric Blake <eblake@redhat.com>, qemu devel <qemu-devel@nongnu.org>, qemu block <qemu-block@nongnu.org>, Stefan Hajnoczi <stefanha@redhat.com>, Fam Zheng <famz@redhat.com>, Max Reitz <mreitz@redhat.com>, Kevin Wolf <kwolf@redhat.com>, Wen Congyang <wency@cn.fujitsu.com>

On 10/11/2016 10:52 PM, Eric Blake wrote:
> On 10/11/2016 05:46 AM, Changlong Xie wrote:
>> Only g_strdup(top_id) if 'top_id' is not NULL, although there
>> is no memory leak here
>>
>> Signed-off-by: Changlong Xie <xiecl.fnst@cn.fujitsu.com>
>> ---
>>   block/replication.c | 4 ++--
>>   1 file changed, 2 insertions(+), 2 deletions(-)
>>
>> diff --git a/block/replication.c b/block/replication.c
>> index 3bd1cf1..5b432d9 100644
>> --- a/block/replication.c
>> +++ b/block/replication.c
>> @@ -104,11 +104,11 @@ static int replication_open(BlockDriverState *bs, QDict *options,
>>       } else if (!strcmp(mode, "secondary")) {
>>           s->mode = REPLICATION_MODE_SECONDARY;
>>           top_id = qemu_opt_get(opts, REPLICATION_TOP_ID);
>> -        s->top_id = g_strdup(top_id);
>
> g_strdup(NULL) is safe; it returns NULL in that case.

Yes, that's why i said 'there is no memory leak here' in the commit 
message.

>
>> -        if (!s->top_id) {
>> +        if (!top_id) {
>>               error_setg(&local_err, "Missing the option top-id");
>>               goto fail;
>>           }
>> +        s->top_id = g_strdup(top_id);
>
> I see no point to this patch, rather than churn.

It just reduce on execution path. Maybe i'm too academic :)
Will remove it in the next series.

Thanks
	-Xie

>