From: Eric Sunshine <sunshine@sunshineco.com>
Date: Sun, 08 Feb 2015 17:09:20 GMT
Subject: Re: read() MAX_IO_SIZE bytes, more than SSIZE_MAX?
Message-ID: <CAPig+cTbLOV-0yFKp8wwVLSr4OJz7LUaLZgVGHUdFhj7xZEzrw@mail.gmail.com>
In-Reply-To: <loom.20150208T125055-287@post.gmane.org>

On Sun, Feb 8, 2015 at 7:05 AM, Joachim Schmitz <jojo@schmitz-digital.de> wrote:
> Junio C Hamano <gitster <at> pobox.com> writes:
>>  (1) if Makefile gives one, use it without second-guessing with SSIZE_MAX.
>>  (2) if SSIZE_MAX is defined, and if it is smaller than our internal
>> default, use it.
>>  (3) all other cases, us our internal default.
>
> oops, yes, of course
>
> /* allow overwriting from e.g. Makefile */
> #ifndef(MAX_IO_SIZE)
> # define MAX_IO_SIZE (8*1024*1024)
>   /* for plattforms that have SSIZE and have it smaller */
> # if defined(SSIZE_MAX) && (SSIZE_MAX < MAX_IO_SIZE)
> #  undef MAX_IO_SIZE /* avoid warning */
> #  define MAX_IO_SIZE SSIZE_MAX
> # endif
> #endif

A bit cleaner:

#ifndef(MAX_IO_SIZE)
# define MAX_IO_SIZE_DEFAULT (8*1024*1024)
# if defined(SSIZE_MAX) && (SSIZE_MAX < MAX_IO_SIZE_DEFAULT)
#  define MAX_IO_SIZE SSIZE_MAX
# else
#  define MAX_IO_SIZE MAX_IO_SIZE_DEFAULT
# endif
#endif