-# Copyright (C) 2019-2020 all contributors <meta@public-inbox.org>
+# Copyright (C) all contributors <meta@public-inbox.org>
# License: AGPL-3.0+ <https://www.gnu.org/licenses/agpl-3.0.txt>
#
# used by PublicInbox::View
# (or reconstruct) blobs.
package PublicInbox::ViewDiff;
-use 5.010_001;
-use strict;
-use warnings;
-use base qw(Exporter);
-our @EXPORT_OK = qw(flush_diff);
+use v5.12;
+use parent qw(Exporter);
+our @EXPORT_OK = qw(flush_diff uri_escape_path);
use URI::Escape qw(uri_escape_utf8);
use PublicInbox::Hval qw(ascii_html to_attr);
use PublicInbox::Git qw(git_unquote);
-sub UNSAFE () { "^A-Za-z0-9\-\._~/" }
-
-my $OID_NULL = '0{7,40}';
-my $OID_BLOB = '[a-f0-9]{7,40}';
+my $OID_NULL = '0{7,}';
+my $OID_BLOB = '[a-f0-9]{7,}';
+my $LF = qr!\n!;
+my $ANY = qr![^\n]!;
+my $FN = qr!(?:"?[^/\n]+/[^\n]+|/dev/null)!;
# cf. git diff.c :: get_compact_summary
-my $DIFFSTAT_COMMENT = qr/\((?:new|gone|(?:(?:new|mode) [\+\-][lx]))\)/;
+my $DIFFSTAT_COMMENT =
+ qr/(?: *\((?:new|gone|(?:(?:new|mode) [\+\-][lx]))\))? *\z/s;
+my $NULL_TO_BLOB = qr/^(index $OID_NULL\.\.)($OID_BLOB)\b/ms;
+my $BLOB_TO_NULL = qr/^index ($OID_BLOB)(\.\.$OID_NULL)\b/ms;
+my $BLOB_TO_BLOB = qr/^index ($OID_BLOB)\.\.($OID_BLOB)/ms;
+our $EXTRACT_DIFFS = qr/(
+ (?: # begin header stuff, don't capture filenames, here,
+ # but instead wait for the --- and +++ lines.
+ (?:^diff\x20--git\x20$FN\x20$FN$LF)
+
+ # old mode || new mode || copy|rename|deleted|...
+ (?:^[a-z]$ANY+$LF)*
+ )? # end of optional stuff, everything below is required
+ ^index\x20($OID_BLOB)\.\.($OID_BLOB)$ANY*$LF
+ ^---\x20($FN)$LF
+ ^\+{3}\x20($FN)$LF)/msx;
+our $IS_OID = qr/\A$OID_BLOB\z/s;
+
+sub uri_escape_path {
+ # '/' + $URI::Escape::Unsafe{RFC3986}
+ uri_escape_utf8($_[0], "^A-Za-z0-9\-\._~/");
+}
# link to line numbers in blobs
-sub diff_hunk ($$$$) {
- my ($dst, $dctx, $ca, $cb) = @_;
+sub diff_hunk ($$$) {
+ my ($dctx, $ca, $cb) = @_;
my ($oid_a, $oid_b, $spfx) = @$dctx{qw(oid_a oid_b spfx)};
if (defined($spfx) && defined($oid_a) && defined($oid_b)) {
- my ($n) = ($ca =~ /^-([0-9]+)/);
- $n = defined($n) ? do { ++$n; "#n$n" } : '';
-
- $$dst .= qq(@@ <a\nhref="$spfx$oid_a/s/$dctx->{Q}$n">$ca</a>);
+ my $n = ($ca =~ /^-([0-9]+)/) ? "#n$1" : '';
+ my $x = qq(@@ <a\nhref="$spfx$oid_a/s/$dctx->{Q}$n">$ca</a>);
- ($n) = ($cb =~ /^\+([0-9]+)/);
- $n = defined($n) ? do { ++$n; "#n$n" } : '';
- $$dst .= qq( <a\nhref="$spfx$oid_b/s/$dctx->{Q}$n">$cb</a> @@);
+ $n = ($cb =~ /^\+([0-9]+)/) ? "#n$1" : '';
+ $x .= qq( <a\nhref="$spfx$oid_b/s/$dctx->{Q}$n">$cb</a> @@);
} else {
- $$dst .= "@@ $ca $cb @@";
+ "@@ $ca $cb @@";
}
}
}
# returns true if diffstat anchor written, false otherwise
-sub anchor0 ($$$$) {
- my ($dst, $ctx, $fn, $rest) = @_;
+sub anchor0 ($$$) {
+ my ($ctx, $fn, $rest) = @_;
my $orig = $fn;
# So only do best-effort handling of renames for common cases;
# which works well in practice. If projects put "=>", or trailing
# spaces in filenames, oh well :P
- $fn =~ s/(?: *$DIFFSTAT_COMMENT)? *\z//so;
- $fn =~ s/{(?:.+) => (.+)}/$1/ or $fn =~ s/.* => (.+)/$1/;
+ $fn =~ s/$DIFFSTAT_COMMENT//;
+ $fn =~ s/\{(?:.+) => (.+)\}/$1/ or $fn =~ s/.* => (.+)/$1/;
$fn = git_unquote($fn);
- # long filenames will require us to walk backwards in anchor1
- if ($fn =~ s!\A\.\.\./?!!) {
- $ctx->{-long_path}->{$fn} = qr/\Q$fn\E\z/s;
- }
+ # long filenames will require us to check in anchor1()
+ push(@{$ctx->{-long_path}}, $fn) if $fn =~ s!\A\.\.\./?!!;
- if (my $attr = to_attr($ctx->{-apfx}.$fn)) {
- $ctx->{-anchors}->{$attr} = 1;
- my $spaces = ($orig =~ s/( +)\z//) ? $1 : '';
- $$dst .= " <a\nid=i$attr\nhref=#$attr>" .
- ascii_html($orig) . '</a>' . $spaces .
+ my $attr = to_attr($ctx->{-apfx}.$fn) // return;
+ $ctx->{-anchors}->{$attr} = 1;
+ my $spaces = ($orig =~ s/( +)\z//) ? $1 : '';
+ print { $ctx->{zfh} } " <a\nid=i$attr\nhref=#$attr>",
+ ascii_html($orig), '</a>', $spaces,
$ctx->{-linkify}->to_html($rest);
- return 1;
- }
- undef;
}
# returns "diff --git" anchor destination, undef otherwise
sub anchor1 ($$) {
my ($ctx, $pb) = @_;
- my $attr = to_attr($ctx->{-apfx}.$pb) or return;
+ my $attr = to_attr($ctx->{-apfx}.$pb) // return;
my $ok = delete $ctx->{-anchors}->{$attr};
- # unlikely, check the end of all long path names we captured:
+ # unlikely, check the end of long path names we captured,
+ # assume diffstat and diff output follow the same order,
+ # and ignore different ordering (could be malicious input)
unless ($ok) {
- my $lp = $ctx->{-long_path} or return;
- foreach my $fn (keys %$lp) {
- $pb =~ $lp->{$fn} or next;
-
- delete $lp->{$fn};
- $attr = to_attr($ctx->{-apfx}.$fn) or return;
- $ok = delete $ctx->{-anchors}->{$attr} or return;
- last;
- }
+ my $fn = shift(@{$ctx->{-long_path}}) // return;
+ $pb =~ /\Q$fn\E\z/s or return;
+ $attr = to_attr($ctx->{-apfx}.$fn) // return;
+ $ok = delete $ctx->{-anchors}->{$attr} // return;
}
$ok ? "<a\nhref=#i$attr\nid=$attr>diff</a> --git" : undef
}
-sub diff_header ($$$$) {
- my ($dst, $x, $ctx, $top) = @_;
+sub diff_header ($$$) {
+ my ($x, $ctx, $top) = @_;
my (undef, undef, $pa, $pb) = splice(@$top, 0, 4); # ignore oid_{a,b}
my $spfx = $ctx->{-spfx};
my $dctx = { spfx => $spfx };
+
+ # get rid of leading "a/" or "b/" (or whatever --{src,dst}-prefix are)
+ $pa = (split(m'/', git_unquote($pa), 2))[1] if $pa ne '/dev/null';
+ $pb = (split(m'/', git_unquote($pb), 2))[1] if $pb ne '/dev/null';
if ($pa eq $pb && $pb ne '/dev/null') {
- $pa = $pb = (split('/', git_unquote($pb), 2))[1];
- $dctx->{Q} = "?b=".uri_escape_utf8($pb, UNSAFE);
+ $dctx->{Q} = '?b='.uri_escape_path($pb);
} else {
my @q;
- if ($pb ne '/dev/null') {
- $pb = (split('/', git_unquote($pb), 2))[1];
- push @q, 'b='.uri_escape_utf8($pb, UNSAFE);
- }
- if ($pa ne '/dev/null') {
- $pa = (split('/', git_unquote($pa), 2))[1];
- push @q, 'a='.uri_escape_utf8($pa, UNSAFE);
- }
+ push @q, 'b='.uri_escape_path($pb) if $pb ne '/dev/null';
+ push @q, 'a='.uri_escape_path($pa) if $pa ne '/dev/null';
$dctx->{Q} = '?'.join('&', @q);
}
# no need to capture oid_a and oid_b on add/delete,
# we just linkify OIDs directly via s///e in conditional
- if (($$x =~ s/^(index $OID_NULL\.\.)($OID_BLOB)\b/
- $1 . oid($dctx, $spfx, $2)/emos) ||
- ($$x =~ s/^index ($OID_BLOB)(\.\.$OID_NULL)\b/
- 'index ' . oid($dctx, $spfx, $1) . $2/emos)) {
- } elsif ($$x =~ /^index ($OID_BLOB)\.\.($OID_BLOB)/mos) {
+ if ($$x =~ s/$NULL_TO_BLOB/$1 . oid($dctx, $spfx, $2)/e) {
+ push @{$ctx->{-qry}->{dfpost}}, $2;
+ } elsif ($$x =~ s/$BLOB_TO_NULL/'index '.oid($dctx, $spfx, $1).$2/e) {
+ push @{$ctx->{-qry}->{dfpre}}, $1;
+ } elsif ($$x =~ $BLOB_TO_BLOB) {
# modification-only, not add/delete:
# linkify hunk headers later using oid_a and oid_b
@$dctx{qw(oid_a oid_b)} = ($1, $2);
+ push @{$ctx->{-qry}->{dfpre}}, $1;
+ push @{$ctx->{-qry}->{dfpost}}, $2;
} else {
warn "BUG? <$$x> had no ^index line";
}
- $$x =~ s!^diff --git!anchor1($ctx, $pb) // 'diff --git'!emos;
- $$dst .= qq(<span\nclass="head">);
- $$dst .= $$x;
- $$dst .= '</span>';
+ $$x =~ s!^diff --git!anchor1($ctx, $pb) // 'diff --git'!ems;
+ print { $ctx->{zfh} } qq(<span\nclass="head">), $$x, '</span>';
$dctx;
}
-sub diff_before_or_after ($$$) {
- my ($dst, $ctx, $x) = @_;
- my $linkify = $ctx->{-linkify};
- for my $y (split(/(^---\r?\n)/sm, $$x)) {
- if ($y =~ /\A---\r?\n\z/s) {
- $$dst .= "---\n"; # all HTML is "\r\n" => "\n"
- } elsif ($y =~ /^ [0-9]+ files? changed, /sm) {
- # ok, looks like a diffstat, go line-by-line:
- for my $l (split(/^/m, $y)) {
- if ($l =~ /^ (.+)( +\| .*\z)/s) {
- anchor0($dst, $ctx, $1, $2) and next;
- }
- $$dst .= $linkify->to_html($l);
- }
- } else { # commit message, notes, etc
- $$dst .= $linkify->to_html($y);
+sub diff_before_or_after ($$) {
+ my ($ctx, $x) = @_;
+ if (exists $ctx->{-anchors} && $$x =~ # diffstat lines:
+ /((?:^\x20(?:[^\n]+?)(?:\x20+\|\x20[^\n]*\n))+)
+ (\x20[0-9]+\x20files?\x20)changed,/msx) {
+ my $pre = substr($$x, 0, $-[0]); # (likely) short prefix
+ substr($$x, 0, $+[0], ''); # sv_chop on $$x ($$x may be long)
+ my @x = ($2, $1);
+ my $lnk = $ctx->{-linkify};
+ my $zfh = $ctx->{zfh};
+ # uninteresting prefix
+ print $zfh $lnk->to_html($pre);
+ for my $l (split(/^/m, pop(@x))) { # $2 per-file stat lines
+ $l =~ /^ (.+)( +\| .*\z)/s and
+ anchor0($ctx, $1, $2) and next;
+ print $zfh $lnk->to_html($l);
}
+ my $ch = $ctx->{changed_href} // '#related';
+ print $zfh pop(@x), # $3 /^ \d+ files? /
+ qq(<a href="$ch">changed</a>,),
+ # insertions/deletions, notes, commit message, etc:
+ $lnk->to_html($$x);
+ } else {
+ print { $ctx->{zfh} } $ctx->{-linkify}->to_html($$x);
}
}
-sub flush_diff ($$$) {
- my ($dst, $ctx, $cur) = @_;
- state $LF = qr!\r?\n!;
- state $ANY = qr![^\r\n]!;
- state $FN = qr!(?:"?[^/\n]+/[^\r\n]+|/dev/null)!;
-
- my @top = split(/(
- (?: # begin header stuff, don't capture filenames, here,
- # but instead wait for the --- and +++ lines.
- (?:^diff\x20--git\x20$FN\x20$FN$LF)
+# callers must do CRLF => LF conversion before calling this
+sub flush_diff ($$) {
+ my ($ctx, $cur) = @_;
- # old mode || new mode || copy|rename|deleted|...
- (?:^[a-z]$ANY+$LF)*
- )? # end of optional stuff, everything below is required
- ^index\x20($OID_BLOB)\.\.($OID_BLOB)$ANY*$LF
- ^---\x20($FN)$LF
- ^\+{3}\x20($FN)$LF)/smxo, $$cur);
- $$cur = undef;
+ my @top = split($EXTRACT_DIFFS, $$cur);
+ undef $$cur; # free memory
- my $linkify = $ctx->{-linkify};
+ my $lnk = $ctx->{-linkify};
my $dctx; # {}, keys: Q, oid_a, oid_b
+ my $zfh = $ctx->zfh;
while (defined(my $x = shift @top)) {
if (scalar(@top) >= 4 &&
- $top[1] =~ /\A$OID_BLOB\z/os &&
- $top[0] =~ /\A$OID_BLOB\z/os) {
- $dctx = diff_header($dst, \$x, $ctx, \@top);
+ $top[1] =~ $IS_OID &&
+ $top[0] =~ $IS_OID) {
+ $dctx = diff_header(\$x, $ctx, \@top);
} elsif ($dctx) {
- my $after = '';
+ open(my $afh, '>>:utf8', \(my $after='')) or
+ die "open: $!";
+
+ # Quiet "Complex regular subexpression recursion limit"
+ # warning. Perl will truncate matches upon hitting
+ # that limit, giving us more (and shorter) scalars than
+ # would be ideal, but otherwise it's harmless.
+ #
+ # We could replace the `+' metacharacter with `{1,100}'
+ # to limit the matches ourselves to 100, but we can
+ # let Perl do it for us, quietly.
+ no warnings 'regexp';
+
for my $s (split(/((?:(?:^\+[^\n]*\n)+)|
(?:(?:^-[^\n]*\n)+)|
(?:^@@ [^\n]+\n))/xsm, $x)) {
+ undef $x;
if (!defined($dctx)) {
- $after .= $s;
+ print $afh $s;
} elsif ($s =~ s/\A@@ (\S+) (\S+) @@//) {
- $$dst .= qq(<span\nclass="hunk">);
- diff_hunk($dst, $dctx, $1, $2);
- $$dst .= $linkify->to_html($s);
- $$dst .= '</span>';
- } elsif ($s =~ /\A\+/) {
- $$dst .= qq(<span\nclass="add">);
- $$dst .= $linkify->to_html($s);
- $$dst .= '</span>';
+ print $zfh qq(<span\nclass="hunk">),
+ diff_hunk($dctx, $1, $2),
+ $lnk->to_html($s),
+ '</span>';
+ } elsif ($s =~ /\A\+/) { # $s may be huge
+ print $zfh qq(<span\nclass="add">),
+ $lnk->to_html($s),
+ '</span>';
} elsif ($s =~ /\A-- $/sm) { # email sig starts
$dctx = undef;
- $after .= $s;
- } elsif ($s =~ /\A-/) {
- $$dst .= qq(<span\nclass="del">);
- $$dst .= $linkify->to_html($s);
- $$dst .= '</span>';
- } else {
- $$dst .= $linkify->to_html($s);
+ print $afh $s;
+ } elsif ($s =~ /\A-/) { # $s may be huge
+ print $zfh qq(<span\nclass="del">),
+ $lnk->to_html($s),
+ '</span>';
+ } else { # $s may be huge
+ print $zfh $lnk->to_html($s);
}
}
- diff_before_or_after($dst, $ctx, \$after) unless $dctx;
+ if (!$dctx) {
+ utf8::decode($after);
+ diff_before_or_after($ctx, \$after);
+ }
} else {
- diff_before_or_after($dst, $ctx, \$x);
+ diff_before_or_after($ctx, \$x);
}
}
}