From bb9c57170922780f241716aa90327874e3efdf31 Mon Sep 17 00:00:00 2001
From: Steven McDonald <steven@steven-mcdonald.id.au>
Date: Sat, 8 Nov 2014 20:39:24 +1100
Subject: [PATCH] Add initial devtree implementation

---
 COPYING           | 13 ++++++++++
 devtree/devtree   | 64 +++++++++++++++++++++++++++++++++++++++++++++++
 devtree/devtree.1 | 36 ++++++++++++++++++++++++++
 3 files changed, 113 insertions(+)
 create mode 100644 COPYING
 create mode 100755 devtree/devtree
 create mode 100644 devtree/devtree.1

diff --git a/COPYING b/COPYING
new file mode 100644
index 0000000..5c93f45
--- /dev/null
+++ b/COPYING
@@ -0,0 +1,13 @@
+            DO WHAT THE FUCK YOU WANT TO PUBLIC LICENSE
+                    Version 2, December 2004
+
+ Copyright (C) 2004 Sam Hocevar <sam@hocevar.net>
+
+ Everyone is permitted to copy and distribute verbatim or modified
+ copies of this license document, and changing it is allowed as long
+ as the name is changed.
+
+            DO WHAT THE FUCK YOU WANT TO PUBLIC LICENSE
+   TERMS AND CONDITIONS FOR COPYING, DISTRIBUTION AND MODIFICATION
+
+  0. You just DO WHAT THE FUCK YOU WANT TO.
diff --git a/devtree/devtree b/devtree/devtree
new file mode 100755
index 0000000..adadaae
--- /dev/null
+++ b/devtree/devtree
@@ -0,0 +1,64 @@
+#!/usr/bin/perl
+
+# Copyright (C) 2014 Steven McDonald <steven@steven-mcdonald.id.au>
+#
+# This program is free software. It comes without any warranty, to the
+# extent permitted by applicable law. You can redistribute it and/or
+# modify it under the terms of the Do What The Fuck You Want To Public
+# License, Version 2, as published by Sam Hocevar. See the COPYING file
+# or visit http://www.wtfpl.net/ for more details.
+
+use strict;
+use warnings;
+
+sub print_tree;
+
+my $tree = {};
+my %name_to_node = (root => $tree);
+my $show_detached = 0;
+
+for (@ARGV) {
+	$show_detached = 1 if /^(-d|--show-detached)$/;
+}
+
+while (<STDIN>) {
+	if (/^(\w+) at (\w+):?\s(.*?["(<])?([^"()<>\n]+)?/) {
+		my $node_prettyname;
+		if ($4) {
+			$node_prettyname = "$1 ($4)";
+		} else {
+			$node_prettyname = $1;
+		}
+
+		my $new_node = {};
+		$name_to_node{$2}{$node_prettyname} = $new_node;
+		$name_to_node{$1} = $new_node;
+	} elsif (/^(\w+) detached$/ and my $node = $name_to_node{$1}) {
+		$node->{_is_detached} = 1;
+	}
+}
+
+print "root\n";
+print_tree $tree;
+exit;
+
+sub print_tree {
+	my $tree        = shift;
+	my $prev_indent = shift || "";
+	my $indent      = $prev_indent . "  |";
+	my $count       = 0;
+	my @keys        = keys $tree;
+
+	for (sort @keys) {
+		my $name = $_;
+		if (delete $tree->{$_}->{_is_detached}) {
+			next unless $show_detached;
+			$name = "$name [DETACHED]";
+		}
+
+		print $indent . "-$name\n";
+		$indent = $prev_indent . "   " if $count eq $#keys;
+		print_tree $tree->{$_}, $indent;
+		$count++;
+	}
+}
diff --git a/devtree/devtree.1 b/devtree/devtree.1
new file mode 100644
index 0000000..122659b
--- /dev/null
+++ b/devtree/devtree.1
@@ -0,0 +1,36 @@
+.\" Copyright (C) 2014 Steven McDonald <steven@steven-mcdonald.id.au>
+.\"
+.\" This work is free. You can redistribute it and/or modify it under
+.\" the terms of the Do What The Fuck You Want To Public License,
+.\" Version 2, as published by Sam Hocevar. See the COPYING file or
+.\" visit http://www.wtfpl.net/ for more details.
+.\"
+.Dd $Mdocdate$
+.Dt DEVTREE 1
+.Os
+.Sh NAME
+.Nm devtree
+.Nd display a tree representing system hardware
+.Sh SYNOPSIS
+.Nm devtree
+.Op Fl d
+.Sh DESCRIPTION
+The
+.Nm
+utility accepts output from
+.Xr dmesg 8
+on standard input, and produces a human-friendly ASCII tree
+representing the currently attached system devices on standard output.
+.Pp
+If the
+.Sy -d
+option is provided, it will also include devices which have
+been detached from the system, appending
+.Em [DETACHED]
+to any such entries. All other options are ignored.
+.Sh EXAMPLES
+Display a tree of all attached devices on the current system:
+.Pp
+.Dl $ dmesg | devtree
+.Sh SEE ALSO
+.Xr dmesg 8
-- 
2.30.2