1#!/usr/bin/perl -w
2#
3# Script to convert .hx file STEXI/ETEXI blocks to SRST/ERST
4#
5# Copyright (C) 2020 Linaro
6#
7# This work is licensed under the terms of the GNU GPL, version 2 or
8# (at your option) any later version. See the COPYING file in the
9# top-level directory.
10
11# This script was only ever intended as a one-off conversion operation.
12# Please excuse the places where it is a bit hacky.
13# Some manual intervention after the conversion is expected, as are
14# some warnings from makeinfo.
15# Warning: this script is not idempotent: don't try to run it on
16# a .hx file that already has SRST/ERST sections.
17
18# Expected usage:
19# scripts/hxtool-conv.pl file.hx > file.hx.new
20
21use utf8;
22
23my $reading_texi = 0;
24my $texiblock = '';
25my @tables = ();
26
27sub update_tables($) {
28    my ($texi) = @_;
29    # Update our list of open table directives: every @table
30    # line in the texi fragment is added to the list, and every
31    # @end table line means we remove an entry from the list.
32    # If this fragment had a completely self contained table with
33    # both the @table and @end table lines, this will be a no-op.
34    foreach (split(/\n/, $texi)) {
35        push @tables, $_ if /^\@table/;
36        pop @tables if /^\@end table/;
37    }
38}
39
40sub only_table_directives($) {
41    # Return true if every line in the fragment is a start or end table directive
42    my ($texi) = @_;
43    foreach (split(/\n/, $texi)) {
44        return 0 unless /^\@table/ or /^\@end table/;
45    }
46    return 1;
47}
48
49sub output_rstblock($) {
50    # Write the output to /tmp/frag.texi, wrapped in whatever current @table
51    # lines we need.
52    my ($texi) = @_;
53
54    # As a special case, if this fragment is only table directives and
55    # nothing else, update our set of open table directives but otherwise
56    # ignore it. This avoids emitting an empty SRST/ERST block.
57    if (only_table_directives($texi)) {
58        update_tables($texi);
59        return;
60    }
61
62    open(my $fragfh, '>', '/tmp/frag.texi');
63    # First output the currently active set of open table directives
64    print $fragfh join("\n", @tables);
65    # Next, update our list of open table directives.
66    # We need to do this before we emit the closing table directives
67    # so that we emit the right number if this fragment had an
68    # unbalanced set of directives.
69    update_tables($texi);
70    # Then emit the texi fragment itself.
71    print $fragfh "\n$texi\n";
72    # Finally, add the necessary closing table directives.
73    print $fragfh "\@end table\n" x scalar @tables;
74    close $fragfh;
75
76    # Now invoke makeinfo/pandoc on it and slurp the results into a string
77    open(my $fh, '-|', "makeinfo --force -o - --docbook "
78         . "-D 'qemu_system_x86 QEMU_SYSTEM_X86_MACRO' "
79         . "-D 'qemu_system     QEMU_SYSTEM_MACRO'  /tmp/frag.texi "
80         . " | pandoc  -f docbook -t rst")
81        or die "can't start makeinfo/pandoc: $!";
82
83    binmode $fh, ':encoding(utf8)';
84
85    print "SRST\n";
86
87    # Slurp the whole thing into a string so we can do multiline
88    # string matches on it.
89    my $rst = do {
90        local $/ = undef;
91        <$fh>;
92    };
93    $rst =~ s/^-  − /-  /gm;
94    $rst =~ s/“/"/gm;
95    $rst =~ s/”/"/gm;
96    $rst =~ s/‘/'/gm;
97    $rst =~ s/’/'/gm;
98    $rst =~ s/QEMU_SYSTEM_MACRO/|qemu_system|/g;
99    $rst =~ s/QEMU_SYSTEM_X86_MACRO/|qemu_system_x86|/g;
100    $rst =~ s/(?=::\n\n +\|qemu)/.. parsed-literal/g;
101    $rst =~ s/:\n\n::$/::/gm;
102
103    # Fix up the invalid reference format makeinfo/pandoc emit:
104    # `Some string here <#anchorname>`__
105    # should be:
106    # :ref:`anchorname`
107    $rst =~ s/\`[^<`]+\<\#([^>]+)\>\`__/:ref:`$1`/gm;
108    print $rst;
109
110    close $fh or die "error on close: $!";
111    print "ERST\n";
112}
113
114# Read the whole .hx input file.
115while (<>) {
116    # Always print the current line
117    print;
118    if (/STEXI/) {
119        $reading_texi = 1;
120        $texiblock = '';
121        next;
122    }
123    if (/ETEXI/) {
124        $reading_texi = 0;
125        # dump RST version of block
126        output_rstblock($texiblock);
127        next;
128    }
129    if ($reading_texi) {
130        # Accumulate the texi into a string
131        # but drop findex entries as they will confuse makeinfo
132        next if /^\@findex/;
133        $texiblock .= $_;
134    }
135}
136
137die "Unexpectedly still in texi block at EOF" if $reading_texi;
138