On Friday 28 February 2014 10:23:11 Wolfgang Denk wrote:
Dear Charles,
sorry, I only send part of the message. Here is the rest.
In message
CAE21AQp2GSPedrDakio1wPa3vGTwjd-3D1wSQM0WhG9r-8Bzcg@mail.gmail.com you wrote:
Both Gerhard and me asked before: Why exactly do we need another implementation of CRC32. We already have some - why cannot we use these?
...
The actual table values I am using are also found in lib/bzlib_crctable.c
So could you use the bzlib implementation for your purposes?
This is, however, not exposed but is a private thing within bzlib.
The best choice would possibly be to expose this with a new crc function, but that means dragging bzlib (or parts thereof) into mkimage or at least putting "hooks" into bzlib that were never intended to be there.
The alternative is to maybe just add a new alt_crc.c to lib.
Code duplication is always bad. Please factor out common code parts.
Ok, I will write a small wrapper thing that accesses the bzlib table.
That table will now be compiled in if you use either bzlib or the alternative crc32.
Does that sound OK?
- Copyright for the CRC code:
- COPYRIGHT (C) 1986 Gary S. Brown. You may use this program, or
- code or tables extracted from it, as desired without
restriction.
I asked before: Please provide _exact_ reference. See
...
Exact reference includes some URL plus version id, etc.
That stuff is now gone
I also commented before: If you really need this copied code (i. e. you canot use one of the already existing implementations of CRC32 - which I seriously doubt), then better move this into a separate file, and assign a separate license ID tag for it.
You say "already exiting implementations". I see only one: lib/crc32.c. Perhaps I am not looking in the right place?
I shall split this code out and call it alt_crc32 and put it in lib with one of those proxy files in tools.
"alt" is a really bad name - you mentioned yourself that ther eis not only one alternative, so please rather use a descriptive name.
Is bzlib_crc32 Ok?
Thank you for your feedback.
-- CHarles