Re: [PATCH master 1/3] common: machine_id: simplify early exit

[Ahmad Fatoum <a.fatoum@pengutronix.de>]

On 08.08.22 13:40, Sascha Hauer wrote:
> On Mon, Aug 08, 2022 at 08:20:08AM +0200, Ahmad Fatoum wrote:
>> We don't need the goto if we haven't done anything to clean up anyway.
>> also globalvar_add_simple("machine_id", NULL) is a no-op when we have
>> just called globalvar_add_simple above with an actual argument.
>> It doesn't clean the parameter, nor should it, because the code is
>> executed for the successful code as well and there is nothing that can
>> fail that late.
>>
>> No functional change.
>>
>> Signed-off-by: Ahmad Fatoum <a.fatoum@pengutronix.de>
>> ---
>>  common/machine_id.c | 6 ++----
>>  1 file changed, 2 insertions(+), 4 deletions(-)
>>
>> diff --git a/common/machine_id.c b/common/machine_id.c
>> index 6480806cd287..a530fdeb1da8 100644
>> --- a/common/machine_id.c
>> +++ b/common/machine_id.c
>> @@ -30,11 +30,11 @@ static int machine_id_set_globalvar(void)
>>  	unsigned char machine_id[SHA1_DIGEST_SIZE];
>>  	char hex_machine_id[MACHINE_ID_LENGTH];
>>  	char *env_machine_id;
>> -	int ret = 0;
>> +	int ret;
>>  
>>  	/* nothing to do if no hashable information provided */
>>  	if (!__machine_id_hashable)
>> -		goto out;
>> +		return 0;
>>  
>>  	digest = digest_alloc_by_algo(HASH_ALGO_SHA1);
>>  	ret = digest_init(digest);
>> @@ -58,8 +58,6 @@ static int machine_id_set_globalvar(void)
>>  	free(env_machine_id);
>>  
>>  out:
>> -	globalvar_add_simple("machine_id", NULL);
> 
> Without this patch we always created a global.machine_id variable,
> either empty or with a value. With this patch we only create this
> variable when it's non-empty. I think this change is ok as we also
> don't have this variable when CONFIG_MACHINE_ID is disabled.
> 
> Still the "No functional change" doesn't hold true, so we should remove
> it from the commit message.

You're right. I missed that. Can you replace the last line with:

  This slightly alters behavior: Whereas before $global.machine_id was
  always defined when CONFIG_MACHINE_ID is enabled, it's now only
  defined when it's non-empty.

Thanks,
Ahmad

> 
> Sascha
> 


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