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Re: Question: xdiff and "pretty" (human readable) diff output

From
Mmatthew@giassa.net <matthew@giassa.net>
Date
Mar 22, 2017, 19:47 UTC
Message-ID
<20170322194751.tpzsnnuaxgt7jyvt@darkstar>
In-Reply-To
<CAGZ79kZ+BGG6yj_rEvjDNf3gmV5KPgvOvLfH94VdPudzbGCkyA@mail.gmail.com>
* Stefan Beller <sbeller@google.com> [2017-03-22 12:43:41 -0700]:
Show 37 quoted lines
>On Wed, Mar 22, 2017 at 12:23 PM,  <matthew@giassa.net> wrote:
>> Good day,
>>
>> I have a question with respect to how git generates "pretty" (ie: human
>> readable) unified diffs. It's to my understanding that git uses its own
>> (simplified/minimized) fork of libxdiff, simply referred to as "xdiff"
>> [1].
>
>correct.
>
>> Which tool/library is used to take the xdiff output and generate
>> the human-readable equivalent that is rendered to the console?
>
>Git itself. Have a look at diff.c (it's only 5k lines of code ;)
>
>Maybe start with fn_out_consume which is a callback (for xdiff)
>that is responsible for pretty printing the output, i.e. transforming the
>output of xdiff according to Gits configuration.
>
>> I have a
>> program that I'm maintaining that currently tracks changes to a couple
>> of "sandboxed" files, and I wanted to add a simple console UI that
>> periodically shows the changes to the files over time and/or dumps the
>> "pretty diff" to syslog.
>
>> over time
>
>So you could use cron for that?
>
>>  "pretty diff" to syslog.
>
>So you want to modify the "pretty diff"?
>Maybe that can be archived by a custom format
>(see the git *log* man page) and doesn't require hacking.
>
>Thanks,
>Stefan
Thank you Stefan. This provides me with everything I need.
Cheers!
-- 
Matthew Giassa
e: matthew@giassa.net
Previous: Stefan Beller
Message 3 of 3 in “Question: xdiff and "pretty" (human readable) diff output”
  1. matthew@giassa.netMar 22, 2017
  2. Stefan BellerMar 22, 2017
  3. matthew@giassa.netMar 22, 2017

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