1 files changed, 100 insertions, 0 deletions
diff --git a/Lib/plat-mac/applesingle.py b/Lib/plat-mac/applesingle.py
new file mode 100644
index 0000000000..f8be3d28e1
--- /dev/null
+++ b/Lib/plat-mac/applesingle.py
@@ -0,0 +1,100 @@
+# applesingle - a module to decode AppleSingle files
+import struct
+import MacOS
+import sys
+
+Error="applesingle.Error"
+
+verbose=0
+
+# File header format: magic, version, unused, number of entries
+AS_HEADER_FORMAT="ll16sh"
+AS_HEADER_LENGTH=26
+# The flag words for AppleSingle
+AS_MAGIC=0x00051600
+AS_VERSION=0x00020000
+
+# Entry header format: id, offset, length
+AS_ENTRY_FORMAT="lll"
+AS_ENTRY_LENGTH=12
+
+# The id values
+AS_DATAFORK=1
+AS_RESOURCEFORK=2
+AS_IGNORE=(3,4,5,6,8,9,10,11,12,13,14,15)
+
+def decode(input, output, resonly=0):
+	if type(input) == type(''):
+		input = open(input, 'rb')
+	# Should we also test for FSSpecs or FSRefs?
+	header = input.read(AS_HEADER_LENGTH)
+	try:
+		magic, version, dummy, nentry = struct.unpack(AS_HEADER_FORMAT, header)
+	except ValueError, arg:
+		raise Error, "Unpack header error: %s"%arg
+	if verbose:
+		print 'Magic:   0x%8.8x'%magic
+		print 'Version: 0x%8.8x'%version
+		print 'Entries: %d'%nentry
+	if magic != AS_MAGIC:
+		raise Error, 'Unknown AppleSingle magic number 0x%8.8x'%magic
+	if version != AS_VERSION:
+		raise Error, 'Unknown AppleSingle version number 0x%8.8x'%version
+	if nentry <= 0:
+		raise Error, "AppleSingle file contains no forks"
+	headers = [input.read(AS_ENTRY_LENGTH) for i in range(nentry)]
+	didwork = 0
+	for hdr in headers:
+		try:
+			id, offset, length = struct.unpack(AS_ENTRY_FORMAT, hdr)
+		except ValueError, arg:
+			raise Error, "Unpack entry error: %s"%arg
+		if verbose:
+			print 'Fork %d, offset %d, length %d'%(id, offset, length)
+		input.seek(offset)
+		if length == 0:
+			data = ''
+		else:
+			data = input.read(length)
+		if len(data) != length:
+			raise Error, 'Short read: expected %d bytes got %d'%(length, len(data))
+		if id == AS_DATAFORK:
+			if verbose:
+				print '  (data fork)'
+			if not resonly:
+				didwork = 1
+				fp = open(output, 'wb')
+				fp.write(data)
+				fp.close()
+		elif id == AS_RESOURCEFORK:
+			didwork = 1
+			if verbose:
+				print '  (resource fork)'
+			if resonly:
+				fp = open(output, 'wb')
+			else:
+				fp = MacOS.openrf(output, 'wb')
+			fp.write(data)
+			fp.close()
+		elif id in AS_IGNORE:
+			if verbose:
+				print '  (ignored)'
+		else:
+			raise Error, 'Unknown fork type %d'%id
+	if not didwork:
+		raise Error, 'No useful forks found'
+
+def _test():
+	if len(sys.argv) < 3 or sys.argv[1] == '-r' and len(sys.argv) != 4:
+		print 'Usage: applesingle.py [-r] applesinglefile decodedfile'
+		sys.exit(1)
+	if sys.argv[1] == '-r':
+		resonly = 1
+		del sys.argv[1]
+	else:
+		resonly = 0
+	decode(sys.argv[1], sys.argv[2], resonly=resonly)
+	
+if __name__ == '__main__':
+	_test()
+	
+\ No newline at end of file