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Minify indirect objects also.
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@deven
deven committed Jan 22, 2021
1 parent 9113aff commit 3fbefff
Showing 1 changed file with 63 additions and 55 deletions.
118 changes: 63 additions & 55 deletions lib/PDF/Data.pm
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Original file line number Diff line number Diff line change
Expand Up @@ -237,7 +237,7 @@ sub pdf_file_data {
# Add cross-reference table.
my $startxref = length($pdf_file_data);
$pdf_file_data .= sprintf "xref\n0 %d\n", scalar @{$xrefs};
$pdf_file_data .= join "", @{$xrefs};
$pdf_file_data .= join("", @{$xrefs});

# Save correct size in trailer dictionary.
$self->{Size} = scalar @{$xrefs};
Expand All @@ -247,6 +247,7 @@ sub pdf_file_data {
$self->write_object(\$pdf_file_data, $objects, $seen, $self, 0);

# Write startxref value.
$pdf_file_data =~ s/\n?\z/\n/;
$pdf_file_data .= "startxref\n$startxref\n";

# End of PDF file data.
Expand Down Expand Up @@ -305,7 +306,7 @@ sub merge_content_streams {
}

# Concatenate stream data and calculate new length.
my $merged = { -data => join "", map { $_->{-data}; } @{$streams} };
my $merged = { -data => join("", map { $_->{-data}; } @{$streams}) };

# Return merged content stream.
return $merged;
Expand Down Expand Up @@ -526,88 +527,89 @@ sub generate_content_stream {
my ($self, $objects) = @_;

# Generated content stream.
local $_ = "";
my $stream = "";

# Loop across parsed objects.
my $last_object;
foreach my $object (@{$objects}) {
# Check parsed object type.
if ($object->[1]{type} eq "dict") {
# Serialize dictionary.
$_ = $self->append_serialization($_, $self->serialize_dictionary($object->[0]));
$self->serialize_dictionary(\$stream, $object->[0]);
} elsif ($object->[1]{type} eq "array") {
# Serialize array.
$_ = $self->append_serialization($_, $self->serialize_array($object->[0]));
$self->serialize_array(\$stream, $object->[0]);
} else {
# Serialize string or other token.
$_ = $self->append_serialization($_, $object->[0]);
$self->serialize_object(\$stream, $object->[0]);
}
} continue {
$last_object = $object;
}

# Return generated content stream.
return $_;
return $stream;
}

# Serialize a hash as a dictionary object.
sub serialize_dictionary {
my ($self, $hash) = @_;

# Serialized dictionary.
local $_ = "<<";
my ($self, $stream, $hash) = @_;

# Serialize the hash key-value pairs.
my @pairs = %{$hash};
${$stream} .= "<<";
for (my $i = 0; $i < @pairs; $i++) {
if ($i % 2) {
my $value = is_hash ($pairs[$i]) ? $self->serialize_dictionary($pairs[$i]) :
is_array($pairs[$i]) ? $self->serialize_array($pairs[$i]) : $pairs[$i];
$_ = $self->append_serialization($_, $value);
if (is_hash($pairs[$i])) {
$self->serialize_dictionary($stream, $pairs[$i]);
} elsif (is_array($pairs[$i])) {
$self->serialize_array($stream, $pairs[$i]);
} else {
$self->serialize_object($stream, $pairs[$i]);
}
} else {
$_ .= "/$pairs[$i]";
${$stream} .= "/$pairs[$i]";
}
}
$_ .= ">>";

# Return serialized dictionary.
return $_;
${$stream} .= ">>";
}

# Serialize an array.
sub serialize_array {
my ($self, $array) = @_;

# Serialized array.
local $_ = "[";
my ($self, $stream, $array) = @_;

# Serialize the array values.
${$stream} .= "[";
foreach my $obj (@{$array}) {
my $value = is_hash ($obj) ? $self->serialize_dictionary($obj) :
is_array($obj) ? $self->serialize_array($obj) : $obj;
$_ = $self->append_serialization($_, $value);
if (is_hash($obj)) {
$self->serialize_dictionary($stream, $obj);
} elsif (is_array($obj)) {
$self->serialize_array($stream, $obj);
} else {
$self->serialize_object($stream, $obj);
}
}
$_ .= "]";

# Return serialized array.
return $_;
${$stream} .= "]";
}

# Append the serialization of an object to the generated content stream.
sub append_serialization {
sub serialize_object {
my ($self, $stream, $object) = @_;

# Strip leading/trailing whitespace from object if minifying.
if ($self->{-minify}) {
$object =~ s/^\s+//;
$object =~ s/\s+$//;
}

# Wrap the line if line length would exceed 255 characters.
$stream .= "\n" if length(($stream =~ /(.*)\z/)[0]) + length($object) >= 255;
${$stream} .= "\n" if length((${$stream} =~ /(.*)\z/)[0]) + length($object) >= 255;

# Add a space if necessary.
$stream .= " " unless $stream =~ /(^|[\s)>\]}])$/ or $object =~ /^[\s()<>\[\]{}\/%]/;
${$stream} .= " " unless ${$stream} =~ /(^|[\s)>\[\]{}])$/ or $object =~ /^[\s()<>\[\]{}\/%]/;

# Add the serialized object.
$stream .= $object;

# Return the new content stream.
return $stream;
${$stream} .= $object;
}

# Validate the specified hash key value.
Expand Down Expand Up @@ -693,7 +695,7 @@ sub parse_objects {
my $type = $token eq "R" ? "reference" : "definition";
"$id->[1]{type} $gen->[1]{type}" eq "int int"
or croak "$id->[0] $gen->[0] $token: Invalid indirect object $type!\n";
my $new_id = join "-", $id->[0], $gen->[0] || ();
my $new_id = join("-", $id->[0], $gen->[0] || ());
push @objects, [
($token eq "R" ? \$new_id : $new_id),
{ type => $token, offset => $id->[1]{offset} }
Expand Down Expand Up @@ -850,6 +852,7 @@ sub write_indirect_objects {
$self->write_object($pdf_file_data, $objects, $seen, $objects->[$i], 0);

# Write the indirect object trailer.
${$pdf_file_data} =~ s/\n?\z/\n/;
${$pdf_file_data} .= "endobj\n\n";
}

Expand Down Expand Up @@ -991,59 +994,64 @@ sub write_object {
}

# Dictionary object.
${$pdf_file_data} .= "<<\n";
$self->serialize_object($pdf_file_data, "<<\n");
foreach my $key (sort { fc($a) cmp fc($b) || $a cmp $b; } keys %{$object}) {
next if $key =~ /^-/;
my $obj = $object->{$key};
$self->add_indirect_objects($objects, $obj) if is_stream $obj;
${$pdf_file_data} .= join "", " " x ($indent + 2), "/$key ";
$self->serialize_object($pdf_file_data, "/$key ");
if (not ref $obj) {
${$pdf_file_data} .= "$obj\n";
$self->serialize_object($pdf_file_data, "$obj\n");
} elsif ($objects->[0]{$obj}) {
${$pdf_file_data} .= "$objects->[0]{$obj} 0 R\n";
$self->serialize_object($pdf_file_data, "$objects->[0]{$obj} 0 R\n");
} else {
$self->write_object($pdf_file_data, $objects, $seen, $object->{$key}, ref $object ? $indent + 2 : 0);
}
}
${$pdf_file_data} .= join "", " " x $indent, ">>\n";
$self->serialize_object($pdf_file_data, ">>\n");

# For streams, write the stream data.
if (is_stream $object) {
croak "Stream written as direct object!\n" if $indent;
my $newline = substr($object->{-data}, -1) eq "\n" ? "" : "\n";
${$pdf_file_data} =~ s/\n?\z/\n/;
${$pdf_file_data} .= "stream\n$object->{-data}${newline}endstream\n";
}
} elsif (is_array $object and not grep { ref $_; } @{$object}) {
# Array of simple objects.
${$pdf_file_data} .= "[ @{$object} ]\n";
if ($self->{-minify}) {
$self->serialize_array($pdf_file_data, $object);
} else {
${$pdf_file_data} .= "[ @{$object} ]\n";
}
} elsif (is_array $object) {
# Array object.
${$pdf_file_data} .= "[\n";
$self->serialize_object($pdf_file_data, "[\n");
my $spaces = " " x ($indent + 2);
foreach my $obj (@{$object}) {
$self->add_indirect_objects($objects, $obj) if is_stream $obj;
${$pdf_file_data} .= $spaces;
${$pdf_file_data} .= $spaces unless $self->{-minify};
if (not ref $obj) {
${$pdf_file_data} .= $obj;
$self->serialize_object($pdf_file_data, $obj);
$spaces = " ";
} elsif ($objects->[0]{$obj}) {
${$pdf_file_data} .= "$objects->[0]{$obj} 0 R\n";
$self->serialize_object($pdf_file_data, "$objects->[0]{$obj} 0 R\n");
$spaces = " " x ($indent + 2);
} else {
$self->write_object($pdf_file_data, $objects, $seen, $obj, $indent + 2);
$spaces = " " x ($indent + 2);
}
}
${$pdf_file_data} .= "\n" if $spaces eq " ";
${$pdf_file_data} .= join "", " " x $indent, "]\n";
${$pdf_file_data} .= "\n" if $spaces eq " " and not $self->{-minify};
$self->serialize_object($pdf_file_data, join("", " " x $indent, "]\n"));
} elsif (reftype($object) eq "SCALAR") {
# Unresolved indirect reference.
my ($id, $gen) = split /-/, ${$object};
$gen ||= "0";
${$pdf_file_data} .= join "", " " x $indent, "($id $gen R)\n";
$self->serialize_object($pdf_file_data, join("", " " x $indent, "($id $gen R)\n"));
} else {
# Simple object.
${$pdf_file_data} .= join "", " " x $indent, "$object\n";
$self->serialize_object($pdf_file_data, join("", " " x $indent, "$object\n"));
}
}

Expand Down Expand Up @@ -1075,7 +1083,7 @@ sub dump_object {
$output .= $self->dump_object($object->{$key}, "$label\{$key\}", $seen, ref $object ? $indent + 2 : 0, $mode) . ",\n";
}
if ($output) {
$output = join "", "{ # $label\n", $output, (" " x $indent), "}";
$output = join("", "{ # $label\n", $output, (" " x $indent), "}");
} else {
$output = "{...}";
}
Expand All @@ -1092,7 +1100,7 @@ sub dump_object {
if ($output =~ /\A\s+(.*?),\n\z/) {
$output = "[... $1]";
} elsif ($output =~ /\n/) {
$output = join "", "[ # $label\n", $output, (" " x $indent), "]";
$output = join("", "[ # $label\n", $output, (" " x $indent), "]");
} else {
$output = "[$output]";
}
Expand Down Expand Up @@ -1128,7 +1136,7 @@ sub dump_object {
$output =~ s/\{ \# \$pdf\n/\{\n/;
} elsif (is_array $object and not grep { ref $_; } @{$object}) {
# Array of simple objects.
$output = sprintf "[%s]", join ", ", map { /^\d+\.\d+$/ ? $_ : dump($_); } @{$object};
$output = sprintf "[%s]", join(", ", map { /^\d+\.\d+$/ ? $_ : dump($_); } @{$object});
} elsif (is_array $object) {
# Array object.
$output .= "[ # $label\n";
Expand Down

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