[[PATCH setup topic/libsolv] 1/2] packagedb::removeEmptyCategories: Don't remove "Base"

[Ken Brown]

On 10/29/2017 1:24 PM, Jon Turney wrote:
> On 28/10/2017 13:29, Ken Brown wrote:
>> This can be empty if no setup.ini files are found.  Removing it causes
>> setup to hang.
>> ---
>> Â  package_db.cc | 2 +-
>> Â  1 file changed, 1 insertion(+), 1 deletion(-)
>>
>> diff --git a/package_db.cc b/package_db.cc
>> index ac9387c..b104073 100644
>> --- a/package_db.cc
>> +++ b/package_db.cc
>> @@ -596,7 +596,7 @@ packagedb::removeEmptyCategories()
>> Â  {
>> Â Â Â  for (packagedb::categoriesType::iterator n = 
>> packagedb::categories.begin();
>> Â Â Â Â Â Â Â Â  n != packagedb::categories.end(); ++n)
>> -Â Â Â  if (!n->second.size())
>> +Â Â Â  if (!n->second.size() && n->first != "Base")
>> Â Â Â Â Â Â Â  {
>> Â Â Â Â Â Â Â Â Â  Log (LOG_BABBLE) << "Removing empty category " << n->first 
>> << endLog;
>> Â Â Â Â Â Â Â Â Â  packagedb::categories.erase (n++);
>>
> 
> Hmm... now I remember my other concerns about this piece of code: as 
> written, it's just wrong.
> 
> 1. Applying erase to packagedb:categories invalidates the iterator
> 2. We're incrementing the iterator after doing an erase, so even if the 
> iterator was still valid, we skip checking if the following category is 
> empty
> 
> So maybe the right way to fix this is as attached:

Yes.  I wrongly jumped to the conclusion that removing Base was the issue.

> I need to stare as this a bit more to understand where the 'base' 
> category is coming from when we have no setup.ini...

I guess it's created implicitly in the 'for' statement in 
packagedb::makeBase().  That's probably a mistake.

Ken