From 7717e7fc3c6640548a1715cea30429a1164aef21 Mon Sep 17 00:00:00 2001
From: Werner Almesberger <werner@almesberger.net>
Date: Wed, 23 May 2012 23:24:38 -0300
Subject: [PATCH] b2/extract-symbols: extract cref-symbol map from KiCad
 schematics

---
 b2/extract-symbols | 82 ++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 82 insertions(+)
 create mode 100755 b2/extract-symbols

diff --git a/b2/extract-symbols b/b2/extract-symbols
new file mode 100755
index 0000000..11ebbe5
--- /dev/null
+++ b/b2/extract-symbols
@@ -0,0 +1,82 @@
+#!/usr/bin/perl
+#
+# extract-symbols - Extract symbol names from KiCad schematics
+#
+# Written 2012 by Werner Almesberger
+# Copyright 2012 Werner Almesberger
+#
+# This program is free software; you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation; either version 2 of the License, or
+# (at your option) any later version.
+#
+
+
+sub usage
+{
+    print STDERR "usage: $0 file.sch\n";
+    exit(1);
+}
+
+
+&usage if $#ARGV != 0;
+
+push @f, $ARGV[0];
+($dir = $ARGV[0]) =~ s|/[^/]*$||;
+$dir = "." if $dir eq "";
+
+while (@f) {
+	$file = pop @f;
+	$sheet = 0;
+	$comp = 0;
+	open(FILE, $file) || die "$file: $!";
+	while (<FILE>) {
+		if (/^\$Sheet/) {
+			$sheet = 1;
+			next;
+		}
+		if (/^\$EndSheet/) {
+			$sheet = 0;
+			next;
+		}
+		if (/^\$Comp/) {
+			$comp = 1;
+			undef $cref;
+			next;
+		}
+		if (/^\$EndComp/) {
+			$comp = 0;
+			next;
+		}
+		if (/^F1 "([^"]*)"/ && $sheet) {
+			if (-r "$1") {
+				push @f, $1;
+			} elsif (-r "$dir/$1") {
+				push @f, "$dir/$1";
+			} else {
+				die "don't know where to find $1";
+			}
+			next;
+		}
+		if (/^L\s+(\S+)\s+([^# \t\n]\S*)\s*$/ && $comp) {
+			die if defined $cref;
+			$cref = $2;
+			$sym = $1;
+			next;
+		}
+		if (/^U\s+1\s+/ && $comp) {
+			next unless defined $cref;
+			die "duplicate component reference \"$cref\" ($sym)" if
+			    defined $sym{$cref};
+			$sym{$cref} = $sym;
+			undef $cref;
+			next;
+		}
+	}
+	close FILE;
+}
+
+for (sort keys %sym) {
+	print "$_ $sym{$_}\n" || die "print: $!";
+}
+close STDOUT || die "close: $!";