Re: [Discuss-gnuradio] possible bug in tag->srcid processing

[Tom Rondeau]

On Wed, Oct 1, 2014 at 7:55 PM, Jeff Long <address@hidden> wrote:

On 10/01/2014 10:47 AM, Tom Rondeau wrote:

On Thu, Sep 25, 2014 at 11:17 PM, Jeff Long <address@hidden
<mailto:address@hidden>> wrote:

    It looks like you're doing it right. The example
    gr-blocks/examples/vector___source_with_tags.grc does the same
    thing, and also fails to report srcid correctly.

    Walked through the process in Python and it works fine.

       In [57]: h = pmt.to_pmt('hello')

       In [58]: type(h)
       Out[58]: pmt.pmt_swig.swig_int_ptr

       In [59]: pmt.is_symbol(h)
       Out[59]: True

    So, probably not a swig problem. Somehow, the 'symbolness' of srcid
    is getting lost before it gets to the tag debug block.

    Removed the is_symbol() check in tag debug, and got this:

       thread[thread-per-block[2]: <block tag_debug (3)>]:
       pmt_symbol_to_string: wrong_type : #f

    Gave up.

    - Jeff


Hey guys,

Can one of you open an issue on the issue tracker? It'd really help if
you can throw up a simple test case, too.

Thanks!

Tom

Turns out that the vector_source does not use the srcid parameter, and the default srcid for a tag is PMT_F, so everything is working correctly, just not as expected. The user-supplied srcid is ignored.

It would seem like a good idea to fill in this field. The question is with what? The srcid supplied with each tag? The actual srcid of the vector_source, ignoring the supplied value?

- Jeff

Ok, gotcha. Thanks.

First, fixing the vector source to respect a set srcid in the input tag is easy. I'll definitely patch that. I can't change the PMT_F as the default for the srcid, though. It's been documented that way since we first created the tags:

http://gnuradio.org/doc/doxygen/classgr_1_1block.html#a8b7cc51b9d289124d6843bb392f564fc

So while it might not be intuitive, it's documented to have this behavior.

I'm also going to make it so that you can use only three items when calling python_to_tag, so you can leave out the optional srcid. Again, will default to PMT_F.

Tom