--- /dev/null
+# Title: TTFMOD.PL
+# Author: M. Hosken
+# Description: Read TTF file calling user functions for each table
+# and output transformed tables to new TTF file.
+# Useage: TTFMOD provides the complete control loop for processing
+# the TTF files. All that the caller need supply is an
+# associative array of functions to call keyed by the TTF
+# table name and the two filenames.
+#
+# &ttfmod($infile, $outfile, *fns [, @must]);
+#
+# *fns is an associative array keyed by table name with
+# values of the name of the subroutine in package main to
+# be called to transfer the table from INFILE to OUTFILE.
+# The subroutine is called with the following parameters and
+# expected return values:
+#
+# ($len, $csum) = &sub(*INFILE, *OUTFILE, $len);
+#
+# INFILE and OUTFILE are the input and output streams, $len
+# is the length of the table according to the directory.
+# The return values are $len = new length of table to be
+# given in the table directory. $csum = new value of table
+# checksum. A way to test that this is correct is to
+# checksum the whole file (e.g. using CSUM.BAT) and to
+# ensure that the value is 0xB1B0AFBA according to a 32 bit
+# checksum calculated bigendien.
+#
+# @must consists of a list of tables which must exist in the
+# final output file, either by being there alread or by being
+# inserted.
+#
+# Modifications:
+# MJPH 1.00 22-SEP-1994 Original
+# MJPH 1.1 18-MAR-1998 Added @must to ttfmod()
+# MJPH 1.1.1 25-MAR-1998 Added $csum to copytab (to make reusable)
+
+package ttfmod;
+
+sub main'ttfmod {
+ local($infile, $outfile, *fns, @must) = @_;
+
+ # open files as binary. Notice OUTFILE is opened for update not just write
+ open(INFILE, "$infile") || die "Unable top open \"$infile\" for reading";
+ binmode INFILE;
+ open(OUTFILE, "+>$outfile") || die "Unable to open \"$outfile\" for writing";
+ binmode OUTFILE;
+
+ seek(INFILE, 0, 0);
+ read(INFILE, $dir_head, 12) || die "Reading table header";
+ ($dir_num) = unpack("x4n", $dir_head);
+ print OUTFILE $dir_head;
+ # read and unpack table directory
+ for ($i = 0; $i < $dir_num; $i++)
+ {
+ read(INFILE, $dir_val, 16) || die "Reading table entry";
+ $dir{unpack("a4", $dir_val)} = join(":", $i, unpack("x4NNN", $dir_val));
+ print OUTFILE $dir_val;
+ printf STDERR "%s %08x\n", unpack("a4", $dir_val), unpack("x8N", $dir_val)
+ if (defined $main'opt_z);
+ }
+ foreach $n (@must)
+ {
+ next if defined $dir{$n};
+ $dir{$n} = "$i:0:-1:0";
+ $i++; $dir_num++;
+ print OUTFILE pack("a4NNN", $n, 0, -1, 0);
+ }
+ substr($dir_head, 4, 2) = pack("n", $dir_num);
+ $csum = unpack("%32N*", $dir_head);
+ $off = tell(OUTFILE);
+ seek(OUTFILE, 0, 0);
+ print OUTFILE $dir_head;
+ seek (OUTFILE, $off, 0);
+ # process tables in order they occur in the file
+ @dirlist = sort byoffset keys(%dir);
+ foreach $tab (@dirlist)
+ {
+ @tab_split = split(':', $dir{$tab});
+ seek(INFILE, $tab_split[2], 0); # offset
+ $tab_split[2] = tell(OUTFILE);
+ if (defined $fns{$tab})
+ {
+ $temp = "main'$fns{$tab}";
+ ($dir_len, $sum) = &$temp(*INFILE, *OUTFILE, $tab_split[3]);
+ }
+ else
+ {
+ ($dir_len, $sum) = ©tab(*INFILE, *OUTFILE, $tab_split[3]);
+ }
+ $tab_split[3] = $dir_len; # len
+ $tab_split[1] = $sum; # checksum
+ $out_dir{$tab} = join(":", @tab_split);
+ }
+ # now output directory in same order as original directory
+ @dirlist = sort byindex keys(%out_dir);
+ foreach $tab (@dirlist)
+ {
+ @tab_split = split(':', $out_dir{$tab});
+ seek (OUTFILE, 12 + $tab_split[0] * 16, 0); # directory index
+ print OUTFILE pack("A4N3", $tab, @tab_split[1..3]);
+ foreach $i (1..3, 1) # checksum directory values with csum twice
+ {
+ $csum += $tab_split[$i];
+ # this line ensures $csum stays within 32 bit bounds, clipping as necessary
+ if ($csum > 0xffffffff) { $csum -= 0xffffffff; $csum--; }
+ }
+ # checksum the tag
+ $csum += unpack("N", $tab);
+ if ($csum > 0xffffffff) { $csum -= 0xffffffff; $csum--; }
+ }
+ # handle main checksum
+ @tab_split = split(':', $out_dir{"head"});
+ seek(OUTFILE, $tab_split[2], 0);
+ read(OUTFILE, $head_head, 12); # read first bit of "head" table
+ @head_split = unpack("N3", $head_head);
+ $tab_split[1] -= $head_split[2]; # subtract old checksum
+ $csum -= $head_split[2] * 2; # twice because had double effect
+ # already
+ if ($csum < 0 ) { $csum += 0xffffffff; $csum++; }
+ $head_split[2] = 0xB1B0AFBA - $csum; # calculate new checksum
+ seek (OUTFILE, 12 + $tab_split[0] * 16, 0);
+ print OUTFILE pack("A4N3", "head", @tab_split[1..3]);
+ seek (OUTFILE, $tab_split[2], 0); # rewrite first bit of "head" table
+ print OUTFILE pack("N3", @head_split);
+
+ # finish up
+ close(OUTFILE);
+ close(INFILE);
+ }
+
+# support function for sorting by table offset
+sub byoffset {
+ @t1 = split(':', $dir{$a});
+ @t2 = split(':', $dir{$b});
+ return 1 if ($t1[2] == -1); # put inserted tables at the end
+ return -1 if ($t2[2] == -1);
+ return $t1[2] <=> $t2[2];
+ }
+
+# support function for sorting by directory entry order
+sub byindex {
+ $t1 = split(':', $dir{$a}, 1);
+ $t2 = split(':', $dir{$b}, 1);
+ return $t1 <=> $t2;
+ }
+
+# default table action: copies a table from input to output, recalculating
+# the checksum (just to be absolutely sure).
+sub copytab {
+ local(*INFILE, *OUTFILE, $len, $csum) = @_;
+
+ while ($len > 0)
+ {
+ $count = ($len > 8192) ? 8192 : $len; # 8K buffering
+ read(INFILE, $buf, $count) == $count || die "Copying";
+ $buf .= "\0" x (4 - ($count & 3)) if ($count & 3); # pad to long
+ print OUTFILE $buf;
+ $csum += unpack("%32N*", $buf);
+ if ($csum > 0xffffffff) { $csum -= 0xffffffff; $csum--; }
+ $len -= $count;
+ }
+ ($_[2], $csum);
+ }
+
+# test routine to copy file from input to output, no changes
+package main;
+
+if ($test_package)
+ {
+ &ttfmod($ARGV[0], $ARGV[1], *dummy);
+ }
+else
+ { 1; }
fnp / librarian.git / blobdiff