From: Jon Smirl <jonsmirl@gmail.com>
Date: Sun, 22 Jul 2007 23:45:58 GMT
Subject: Re: Git help for kernel archeology, suppress diffs caused by CVS keyword expansion
Message-ID: <9e4733910707221645x21d74e70y3c43bc8c02a9d4ca@mail.gmail.com>
In-Reply-To: <Pine.LNX.4.64.0707222238180.14781@racer.site>

On 7/22/07, Johannes Schindelin <Johannes.Schindelin@gmx.de> wrote:
> As you already did, this is my attempt at a perl script...  Feel free to
> bash my Perl capabilities, or to correct it...

I don't really know Perl but Perl is probably a better language for
this. I was doing it in C.
This doesn't run on the two full kernel samples I sent you. That's the
problem I was having, I can catch 95% of the expanded keywords with my
program but I have to touch up 5% by hand. I'll stare at this and see
if I can increase my understanding of Perl.

>
> Ciao,
> Dscho
>
> -- snipsnap --
> #!/usr/bin/perl
>
> sub init_hunk {
>         $_ = $_[0];
>         $current_hunk = "";
>         $current_hunk_header = $_;
>         ($start_minus, $dummy, $start_plus, $dummy) =
>                 /^\@\@ -(\d+)(,\d+|) \+(\d+)(,\d+|) \@\@/;
>         $plus = $minus = $space = 0;
>         $skip_logs = 0;
> }
>
> sub flush_hunk {
>         if ($plus > 0 || $minus > 0) {
>                 if ($current_file ne "") {
>                         print $current_file;
>                         $current_file = "";
>                 }
>                 $minus += $space;
>                 $plus += $space;
>                 print "\@\@ -$start_minus,$minus "
>                         . "+$start_plus,$plus \@\@\n";
>                 print $current_hunk;
>         }
> }
>
> sub check_file {
>         $_ = $_[0];
>         $current_file = $_;
>         while (<>) {
>                 if (/^\@\@/) {
>                         last;
>                 }
>                 $current_file .= $_;
>         }
>
>         init_hunk $_;
>
>         # check hunks
>         while (<>) {
>                 if ($skip_logs && /^\+ *\*/) {
>                         # do nothing
>                 } elsif (/^\@\@.*/) {
>                         flush_hunk;
>                         init_hunk $_;
>                 } elsif (/^diff/) {
>                         flush_hunk;
>                         return;
>                 } elsif (/^-.*\$(Id|Revision|Author|Date).*\$/) {
>                         $key = $1;
>                         s/^-/ /;
>                         $current_hunk .= $_;
>                         $space++;
>                         $_ = <>;
>                         if (!/\+.*\$Id.*\$/) {
>                                 die "Expected some changed \$$key line: $_";
>                         }
>                         $skip_logs = 0;
>                 } elsif (/^ .*\$Log.*\$/) {
>                         $current_hunk .= $_;
>                         $space++;
>                         $skip_logs++;
>                 } elsif (/^ /) {
>                         $current_hunk .= $_;
>                         $space++;
>                         $skip_logs = 0;
>                 } elsif (/^\+/) {
>                         $current_hunk .= $_;
>                         $plus++;
>                 } elsif (/^-/) {
>                         $current_hunk .= $_;
>                         $minus++;
>                         $skip_logs = 0;
>                 } else {
>                         die "Unexpected line: $_";
>                 }
>         }
> }
>
> while (<>) {
>         if (/^diff/) {
>                 do {
>                         check_file $_;
>                 } while(/^diff/);
>         } else {
>                 printf $_;
>         }
> }
>


-- 
Jon Smirl
jonsmirl@gmail.com