Re: [dpdk-dev] Question about librte_cmdline

[Igor Ryzhov <iryzhov@arccn.ru>]

Thank you.

That’s not a really big problem that we need it’s own structure for every command, but the lack of optional parameters is a problem.

For example:
	object add IP [port]

	it’s just one command, but we need two different structures - with and without «port»

Maybe I’ll work on it sometime later.

> 14 нояб. 2014 г., в 14:14, Olivier MATZ <olivier.matz@6wind.com> написал(а):
> 
> Hi Igor,
> 
> Adding-back the list to the discussion, I removed it by mistake in my
> first answer.
> 
>>> 14 нояб. 2014 г., в 12:20, Olivier MATZ <olivier.matz@6wind.com> написал(а):
>>> 
>>> Hi Igor,
>>> 
>>> On 11/14/2014 09:52 AM, Igor Ryzhov wrote:
>>>> Are there any docs with detailed description of cmdline library?
>>>> I found only some information in «DPDK Sample Apps» document, but it describes only a couple of features.
>>> 
>>> In my knowledge, there is no such documentation.
>>> You can also refer to testpmd that gives a lot of different commands.
>>> 
>>> If you have any question, you can ask on the list.
>>> 
>>> Regards,
>>> Olivier
>> 
>> Thank you, I’ll check testpmd.
>> 
>> At the moment I have a question - is there a possibility to have optional tokens in one command?
>> 
>> For example:
>> 
>> I have one command - «object» and two subcommands - «add» and «del»:
>> 
>> 	object add name IP
>> 	object del name
>> 
>> And the question is - can I have just one context instruction for this? Something like that:
>> 
>> Result struct:
>> 
>> struct object_result {
>> 	cmdline_fixed_string_t object;
>> 	cmdline_fixed_string_t cmd;
>> 	cmdline_fixed_string_t name;
>> 	cmdline_ipaddr_t ip;			// I need it optional - only for «add» case
>> }
>> 
>> And tokens:
>> 
>> cmdline_parse_token_string_t object =
>> 	TOKEN_STRING_INITIALIZER(struct object_result, object, "object");
>> cmdline_parse_token_string_t cmd =
>> 	TOKEN_STRING_INITIALIZER(struct object_result, cmd, "add#del");
>> cmdline_parse_token_string_t name =
>> 	TOKEN_STRING_INITIALIZER(struct object_result, name, NULL);
>> cmdline_parse_token_ipaddr_t ip =
>> 	TOKEN_IPV4_INITIALIZER(struct object_result, ip, NULL);
>> 
>> As I understand investigating the code of sample application - all tokens are required (because there are two different instructions - for «add» and for «del/show»).
>> And in this example configuration there is no possibility for string «object del name» without last IP token.
>> So I need to have two different context instructions - one for «add» and one for «del».
>> Am I right?
> 
> Right, there is no way to declare an optional token in one instruction.
> But if there are few case (ex: a "set" and a "show" intructions), you
> can factorize the structure and the callback function. There is an
> example in my latest TSO patch:
> http://dpdk.org/ml/archives/dev/2014-November/007962.html
> 
> Regards,
> Olivier