podman

1
#!/usr/bin/perl
2

3
(our $ME = $0) =~ s|^.*/||;
4

5
use v5.20;
6

7
our $DSM = 'docs/source/markdown';
8

9
my ($oldname, $newname);
10
my %oldname;
11
my %changed;
12
open my $git_diff, '-|', 'git', 'log', '-1', '-p'
13
    or die "$ME: Cannot fork: $!\n";
14
while (my $line = <$git_diff>) {
15
    chomp $line;
16

17
    if ($line =~ m!^\-\-\-\s+a/$DSM/(podman-\S+\.md(\.in)?)!) {
18
        $oldname = $1;
19
        $newname = undef;
20
    }
21
    elsif ($line =~ m!^\+\+\+\s+b/$DSM/(podman-\S+\.md(\.in)?)!) {
22
        $newname = $1;
23
        $oldname{$newname} = $oldname;
24
    }
25
    elsif ($newname) {
26
        if ($line =~ s/^-####\s+//) {
27
            $line =~ /^\*\*--(\S+?)\*\*/
28
                or die "$ME: in $newname: weird '$line'";
29
            $changed{$newname}{$1}{name} //= $1;
30
        }
31
        # Usually the same, but not for host.container and host.pod.md
32
        elsif ($line =~ /^\+\@\@option\s+(\S+)/) {
33
            my $optfile = $1;
34
            if ($optfile =~ /^(.*)\.\S+$/) {
35
                $changed{$newname}{$1}{name} = $optfile;
36
            }
37
        }
38
    }
39
}
40
close $git_diff;
41

42
# Pass 2: read each oldfile, parse changed options
43
for my $f (sort keys %changed) {
44
    my $oldfile = $oldname{$f};
45
    open my $git_fh, '-|', 'git', 'show', "HEAD^:$DSM/$oldfile"
46
        or die "$ME: Cannot fork: $!\n";
47
    my $opt;
48
    while (my $line = <$git_fh>) {
49
        if ($line =~ /^####\s+\*\*--(\S+?)\*\*/) {
50
            $opt = $1;
51
            if ($changed{$f}{$opt}) {
52
                $changed{$f}{$opt}{text} = $line;
53
            }
54
            else {
55
                undef $opt;
56
            }
57
        }
58
        elsif ($line =~ /^#/ || $line =~ /^\@\@option\s/) {
59
            undef $opt;
60
        }
61
        elsif ($opt) {
62
            $changed{$f}{$opt}{text} .= $line;
63
        }
64
    }
65
    close $git_fh
66
        or die "$ME: Error running git on $oldfile\n";
67
}
68

69
# Pass 3: write out files
70
my $tempdir = "/tmp/$ME.diffs";
71
system('rm', '-rf', $tempdir);
72
mkdir $tempdir, 0755;
73

74
for my $md_file (sort keys %changed) {
75
    for my $opt (sort keys %{$changed{$md_file}}) {
76
        my $d = "$tempdir/$changed{$md_file}{$opt}{name}";
77
        mkdir $d, 0755;
78

79
        my $outfile = "$d/$md_file";
80
        open my $fh, '>', $outfile
81
            or die "$ME: Cannot create $outfile: $!\n";
82
        # strip all trailing newlines
83
        (my $text = $changed{$md_file}{$opt}{text}) =~ s/\n+$/\n/s;
84
        print { $fh } $text;
85
        close $fh
86
            or die "$ME: Error writing $outfile: $!\n";
87

88
        my $new_text = "$DSM/options/$changed{$md_file}{$opt}{name}.md";
89
        die "$ME: $md_file: File does not exist: $new_text\n" if ! -e $new_text;
90
        system('cp', $new_text, "$d/zzz-chosen.md");
91
    }
92
}
93

94
# Now run diffuse
95
chdir $tempdir or die;
96
my @all_opts = glob("*");
97
for my $i (0..$#all_opts) {
98
    my $opt = $all_opts[$i];
99
    chdir "$tempdir/$opt"
100
        or die "??? Internal error, cannot cd $tempdir/$opt: $!";
101

102
    $| = 1; printf "--%s (%d/%d) ", $opt, $i+1, scalar(@all_opts);
103

104
    my @all_files = glob("*");
105
    if (all_files_identical(@all_files)) {
106
        pop @all_files;
107
        print "[identical between @all_files]\n";
108
        next;
109
    }
110

111
    # Prompt
112
    print "[Y/n/q] ";
113
    my $ans = <STDIN>;
114
    next if $ans =~ /^n/i;
115
    exit 0 if $ans =~ /^q/i;
116

117
    # Try to cull the files (remove identical ones)
118
    my @files = glob("*");
119
    my $winner = pop @files;
120

121
    for my $f (@files) {
122
        system('cmp', '-s', $f, $winner);
123
        if ($? == 0) {
124
            print "[ $f is the one we went with; removing from list ]\n";
125
            unlink $f;
126
            next;
127
        }
128

129
        system('wdiff', '-1', '-2', '-3', $f, $winner);
130
        if ($? == 0) {
131
            print "[ $f is whitespace-identical with what we went with ]\n";
132
            unlink $f;
133
            next;
134
        }
135
    }
136

137
    # Recompute @files, in case some were deleted above
138
    @files = glob("*"); pop @files;
139

140
    for (my $i=0; $i < $#files; $i++) {
141
        my $f1 = $files[$i];
142
        next unless -e $f1;
143

144
        for (my $j=$i+1; $j <= $#files; $j++) {
145
            my $f2 = $files[$j];
146
            next unless -e $f2;
147

148
            system('wdiff', '-1', '-2', '-3', $f1, $f2);
149
            if ($? == 0) {
150
                print "[ $f2 : removing, it =~ $f1 ]\n";
151
                unlink $f2;
152
            }
153
        }
154
    }
155

156
    # Recompute @files, in case some were deleted above
157
    @files = glob("*");
158

159
    # diffuse works great for 3-4 files, passable for 5, not at all for >5
160
    if (@files <= 5) {
161
        system("diffuse", "-w", @files) == 0
162
            or die "Diffuse failed\n";
163
    }
164
    else {
165
        # Too many files. Go by threes.
166
        my $winner = pop @files;
167
        for (my $i=0; $i < @files; $i += 3) {
168
            system("diffuse", "-w", @files[$i..$i+2], $winner);
169
        }
170
    }
171
}
172

173

174
sub all_files_identical {
175
    my %sha;
176
    for my $f (@_) {
177
        my $result = qx{sha256sum $f};
178
        $result =~ /^([0-9a-f]+)\s/
179
            or die "Internal error: unexpected result from sha256sum $f: $result";
180
        $sha{$1}++;
181
    }
182

183
    return (keys(%sha) == 1);
184
}
185