[bitbake-devel] [PATCH 7/8] bitbake: cooker: fix event notifications

[Robert Yang]

Hi RP,

On 02/02/2018 07:19 PM, Richard Purdie wrote:
> On Thu, 2018-02-01 at 23:15 +0800, Robert Yang wrote:
>> There are two kinds of events:
>> * directory
>>    We always need handle the event since we don't know what inside the
>>    directory, for example:
>>    $ bitbake --server-only -T -1
>>    $ bitbake -p
>>    $ mkdir ${TOPDIR}/classes
>>    $ cp /path/to/base.bbclass classes
>>
>>    The "${TOPDIR}/classes" is a new directory, the event only reports
>> that the
>>    directory is created, we don't know there is a base.bbclass unless
>> the parser
>>    runs.
>>
>> * file:
>>    Use bb.parse.supports() to check whether bitbake supports it or
>> not.
>>
>> And now the bbwatchedfiles is not needed anymore.
>>
>> Signed-off-by: Robert Yang <liezhi.yang at windriver.com>
>> ---
>>   bitbake/lib/bb/cooker.py | 34 ++++++++++++++++++----------------
>>   1 file changed, 18 insertions(+), 16 deletions(-)
> 
> I'm not sure you can do this. For example, bitbake itself doesn't
> know/care about *.patch files, however if one is referenced in a
> SRC_URI and ends up on the watch list, would this change break a patch
> file changing causing task checksums to change?

I can confirm the the following 2 things:
1) The watcher only watches __depends (and __base_depends) which only contains
    files supported by bb.parse.supports(), so use bb.parse.supports() to check
    it is OK (or maybe it is the best way).

2) The *.patch is not part of of __depends, but file_checksums, and they are not
    watched by watchers. When a patch is updated, it would compare the saved
    mtime and current mtime (in lib/bb/checksum.py), and decide whether need
    recompute.

So I think that this patch is fine.

The testcase:

$ bitbake --server-only -T -1
$ bitbake quilt-native

# Update quilt-native's patch to test the rebuild:
$ echo "hello world" >> 
/path/to/meta/recipes-devtools/quilt/quilt/0001-tests-Allow-different-output-from-mv.patch

# Build quilt-native again
$ bitbake quilt-native

NOTE: Tasks Summary: Attempted 10 tasks of which 0 didn't need to be rerun and 
all succeeded.

We can see that it has been rebuilt.

// Robert

> 
> Its looking like we need better tests for some of this code too :/.
> 
> Cheers,
> 
> Richard
> 
>