Re: [PATCH] gnu: Add most debian patches to nvi.

[Marek Benc <merkur32@gmail.com>]

On 01/22/2015 05:05 PM, Ludovic Courtès wrote:
> Marek Benc <merkur32@gmail.com> skribis:
>
>> On 01/21/2015 04:03 PM, Ludovic Courtès wrote:
>>> I agree with Andreas: there are 20 patches, and that level of patching
>>> goes beyond our mission, IMO.
>>>
>>> I would rather leave it as is if it’s usable, or remove it, or point to
>>> a new upstream if there is one.
>> In that case, I think at least two of the patches should be allowed to
>> get in, the ones about the Berkely db library, since it's spewing out
>> errors without them. (but the editor itself works)
> You mean there are run-time errors without nvi-db4.patch?  What kind?

I mistyped, it's only warnings, the editor seems to work okay. In 
particular,
the warnings look like this:

BDB0635 DB_CREATE must be specified to create databases.
BDB0511 page sizes must be a power-of-2

> The second patch is about page sizes apparently.  Do you know what the
> deal is?

nvi seems to store the data of files in Berkely DB database objects, and 
when
setting up a database for a file, it determines a page size to fit the file
into 15 pages or less, using a page size of at least 1K and at most 10K.

The way it does the calculation, I quote:
   psize = ((sb.st_size / 15) + 1023) / 1024;
   if (psize > 10)
     psize = 10;
   if (psize == 0)
     psize = 1;
   psize *= 1024;

makes psize hold a variable that's a multiple of 1024, but not necessarilya
power of two (for example, 3072). This didn't use to be a problem 
before, but
nowadays, BDB requires pages to be powers of two, and so the modified 
code, I
quote:

   psize = ((sb.st_size / 15) + 1023) / 1024;
   if (psize >= 8) psize=8<<10;
   else if (psize >= 4) psize=4<<10;
   else if (psize >= 2) psize=2<<10;
   else psize=1<<10;
   psize *= 1024;

fixes that problem.

> Two/three patches would be OK, but we need to have an understanding of
> why we’re carrying these particular patches.

Sure, I understand.

>
> Thank you!
>
> Ludo’.

Marek