Re: [PATCH 1/2] add macro REALLOC_ARRAY

From: Michael Haggerty <mhagger@alum.mit.edu>
Date: Sep 24, 2014, 07:32 UTC
Message-ID: <54227379.5010708@alum.mit.edu>
In-Reply-To: <541887F0.1050007@web.de>

On 09/16/2014 08:56 PM, René Scharfe wrote:

Show 11 quoted lines

> The macro ALLOC_GROW manages several aspects of dynamic memory
> allocations for arrays: It performs overprovisioning in order to avoid
> reallocations in future calls, updates the allocation size variable,
> multiplies the item size and thus allows users to simply specify the
> item count, performs the reallocation and updates the array pointer.
> 
> Sometimes this is too much.  Add the macro REALLOC_ARRAY, which only
> takes care of the latter three points and allows users to specfiy the
> number of items the array can store.  It can increase and also decrease
> the size.  Using the macro avoid duplicating the variable name and
> takes care of the item sizes automatically.

Is there a reason that ALLOC_GROW and REALLOC_ARRAY are defined in two separate header files (cache.h and git-compat-util.h, respectively)? It seems to me that they are close siblings and therefore I find it surprising that they are not defined right next to each other.

It's true that ALLOC_GROW contains a *tiny* bit of application logic in the form of the alloc_nr macro used to compute the new size of the array, but it's still pretty generic.

Michael

-- 
Michael Haggerty
mhagger@alum.mit.edu