From mboxrd@z Thu Jan  1 00:00:00 1970
From: Jonathan Nieder <jrnieder@gmail.com>
Subject: Re: Refactoring hardcoded SHA-1 constants
Date: Fri, 18 Apr 2014 15:40:49 -0700
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References: <20140418221841.GC57656@vauxhall.crustytoothpaste.net>
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To: "brian m. carlson" <sandals@crustytoothpaste.net>
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Hi,

brian m. carlson wrote:

> I'd like to introduce a set of preprocessor constants that we'd use
> instead of hard-coded 20s and 40s everywhere.

Lukewarm on that.  It's hard to do consistently and unless they're
named well it can be harder to know what something like
BINARY_OBJECT_NAME_LENGTH means than plain '20' when first reading.

[...]
> I would also like to consider, as a third step, turning all of the
> unsigned char[20] uses into a struct containing unsigned char[20] as its
> only member, like libgit2 does.

That would be very welcome!

It's a nice way to steer people toward hashcmp using the type system,
and it makes it possible to use a union to enforce alignment later if
measurements show benefit.

Thanks,
Jonathan