Re: Git help for kernel archeology, suppress diffs caused by CVS keyword expansion
Next try. It includes documentation, skips $Source:$ and $Header:$ as well, and the output diff does not contain any CVS keywords.
Ah yes, and if a file was actually created, it substitutes the --- file name with /dev/null. In that case, the keywords are skipped, too! However, when a file was deleted, they are _not_ skipped.
Strictly speaking, it is wrong to just cut out the lines containing CVS keywords, since it is possible that there is an important change on that line, but we can cross that bridge once companies play such cute games with us.
But at least I tested the resulting patch with your phytec3180 patch this time...
Ciao, Dscho
-- snipsnap -- #!/usr/bin/perl
# This is a simple state machine. # # There is the state of the current file; its header is stored # in $current_file to avoid outputting it when all hunks were # culled. It is only printed before the first hunk, and then # set to "" to avoid outputting it twice. # # There are the states of the current hunk, stored in # * $current_hunk (possibly modified hunk) # * $start_minus, $start_plus (from the original) # * $plus, $minus, $space (the current count of the respective lines) # a hunk is only printed (in flush_hunk) if any '+' or '-' lines # are left after filtering. # # For $Log..$, there is the state $skip_logs, which is set to 1 # after seeing such a line, and set to 0 when the first line # was seen which does not begin with '+'. # # A particularly nasty special case is when a single "*" was # misattributed by the diff to be _inserted before_ a $Log, instead # of _appended after_ a $Log. # This is the purpose of the $before_log and $after_log variables: # if not empty, the state machine expects the next line to begin # with '+' or '-', respectively, and followed by a $Log. If this # expectation is not met, the variable is output. # # The variable $plus_minus_adjust contains the number of lines which # were skipped from the "+" side, so that the correct offset is shown.
# This function gets a hunk header. # # It initializes the state variables described above
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;
$before_log = '';
$after_log = ''; # we prefer /dev/null as original file name when a file is new
if ($start_minus eq 0) {
$current_file =~ s/\n--- .*\n/\n--- \/dev\/null\n/;
} elsif ($start_plus eq 0) {
$current_file =~ s/\n\+\+\+ .*\n/\n+++ \/dev\/null\n/;
}
}# This function is called whenever there is possibly a hunk to print. # Nothing is printed if no '+' or '-' lines are left. # Otherwise, if the file header was not yet shown, it does so now.
sub flush_hunk {
if ($plus > 0 || $minus > 0) {
if ($current_file ne "") {
print $current_file;
$current_file = "";
}
$minus += $space;
$plus += $space;
print "\@\@ -$start_minus,$minus "
. "+" . ($start_plus - $start_plus_adjust)
. ",$plus \@\@\n";
print $current_hunk;
}
}# This adds a line to the current hunk and updates $space, $plus or $minus
sub add_line {
my $line = $_[0];
$current_hunk .= $line;
if ($line =~ /^ /) {
$space++;
} elsif ($line =~ /^\+/) {
$plus++;
} elsif ($line =~ /^-/) {
$minus++;
} elsif ($line =~ /^\\/) {
# do nothing
} else {
die "Unexpected line: $line";
}
}# This function splits the current hunk into the part before the current # line, and the part after the current line.
sub skip_line {
my $line = $_[0]; if ($start_minus == 0) {
# This patch adds a new file, just ignore that line
return;
} elsif ($start_plus == 0) {
# This patch removes a file, so include the line nevertheless
add_line $_;
return;
} flush_hunk;
if ($line =~ /^-/) {
$minus++;
} elsif ($line =~ /^\+/) {
$plus++;
$start_plus_adjust++;
}
init_hunk "@@ -" . ($start_minus + $minus + $space)
. " +" . ($start_plus + $plus + $space)
. " @@\n";
}$simple_keyword = "Id|Revision|Author|Date|Source|Header";
# This is the main loop
sub check_file {
$_ = $_[0];
$current_file = $_;
$start_plus_adjust = 0;
while (<>) {
if (/^\@\@/) {
last;
}
$current_file .= $_;
} init_hunk $_;
# check hunks
while (<>) {
if ($before_log) {
if (!/\+.*\$Log.*\$/) {
add_line $before_log;
} else {
skip_line $before_log;
}
$before_log = '';
} if ($after_log) {
if (!/-.*\$Log.*\$/) {
add_line $after_log;
} else {
skip_line $after_log;
}
$after_log = '';
} if ($skip_logs) {
if (/^\+/) {
skip_line $_;
$skip_logs = 1;
} else {
$skip_logs = 0;
if (/^ *\*$/) {
$after_log = $_;
}
}
} elsif (/^\+.*\$($simple_keyword).*\$/) {
skip_line $_;
} elsif (/^\@\@.*/) {
flush_hunk;
init_hunk $_;
} elsif (/^diff/) {
flush_hunk;
return;
} elsif (/^-.*\$($simple_keyword).*\$/) {
# fake new hunk
skip_line $_;
} elsif (/^\+ *\*$/) {
$before_log = $_;
} elsif (/^([- \+]).*\$Log.*\$/) {
skip_line $_;
$skip_logs = 1;
} else {
add_line $_;
}
}
}# This loop just shows everything before the first diff, and then hands # over to check_file whenever it sees a line beginning with "diff".
while (<>) {
if (/^diff/) {
do {
check_file $_;
} while(/^diff/);
flush_hunk;
} else {
printf $_;
}
}
Jon Smirl
