Add python_requires to setup.py

README.rst

@@ -85,7 +85,8 @@ Command-line interface
 	$ python3 -m rsrcfork /Users/Shared/Test.textClipping "'TEXT' (256)"
 	Resource 'TEXT' (256), unnamed, no attributes, 17 bytes:
 	00000000 48 65 72 65 20 69 73 20 73 6f 6d 65 20 74 65 78 |Here is some tex|
-	00000010 74                                              |t               |
+	00000010 74                                              |t|
+	00000011
 	
 
 Limitations
@@ -138,6 +139,12 @@ __ https://archive.fo/
 Changelog
 ---------
 
+Version 1.1.1
+`````````````
+
+* Fixed overflow issue with empty resource files or empty resource type entries
+* Changed ``_hexdump`` to behave more like ``hexdump -C``
+
 Version 1.1.0
 `````````````
 

rsrcfork.py

@@ -22,7 +22,7 @@ __all__ = [
 	"open",
 ]
 
-__version__ = "1.1.0"
+__version__ = "1.1.1"
 
 # Translation table to replace ASCII non-printable characters with periods.
 _TRANSLATE_NONPRINTABLES = {k: "." for k in [*range(0x20), 0x7f]}
@@ -345,14 +345,16 @@ class ResourceFile(collections.abc.Mapping):
 		self._reference_counts: typing.MutableMapping[bytes, int] = collections.OrderedDict()
 		
 		(type_list_length_m1,) = self._stream_unpack(STRUCT_RESOURCE_TYPE_LIST_HEADER)
+		type_list_length = (type_list_length_m1 + 1) % 0x10000
 		
-		for _ in range(type_list_length_m1 + 1):
+		for _ in range(type_list_length):
 			(
 				resource_type,
 				count_m1,
 				reflist_offset,
 			) = self._stream_unpack(STRUCT_RESOURCE_TYPE)
-			self._reference_counts[resource_type] = count_m1 + 1
+			count = (count_m1 + 1) % 0x10000
+			self._reference_counts[resource_type] = count
 	
 	def _read_all_references(self):
 		"""Read all resource references, starting at the current stream position."""
@@ -575,7 +577,10 @@ def _hexdump(data: bytes):
 		line = data[i:i + 16]
 		line_hex = " ".join(f"{byte:02x}" for byte in line)
 		line_char = line.decode("MacRoman").translate(_TRANSLATE_NONPRINTABLES)
-		print(f"{i:08x} {line_hex:<{16*2+15}} |{line_char:<16}|")
+		print(f"{i:08x} {line_hex:<{16*2+15}} |{line_char}|")
+	
+	if data:
+		print(f"{len(data):08x}")
 
 def _raw_hexdump(data: bytes):
 	for i in range(0, len(data), 16):
@@ -745,25 +750,28 @@ def main(args: typing.Sequence[str]):
 			else:
 				print("No file attributes")
 			
-			print(f"{len(rf)} resource types:")
+			if len(rf) > 0:
-			for typecode, resources in rf.items():
+				print(f"{len(rf)} resource types:")
-				restype = _bytes_escape(typecode, quote="'")
+				for typecode, resources in rf.items():
-				print(f"'{restype}': {len(resources)} resources:")
+					restype = _bytes_escape(typecode, quote="'")
-				for resid, res in rf[typecode].items():
+					print(f"'{restype}': {len(resources)} resources:")
-					if res.name is None:
+					for resid, res in rf[typecode].items():
-						name = "unnamed"
+						if res.name is None:
-					else:
+							name = "unnamed"
-						name = _bytes_escape(res.name, quote='"')
+						else:
-						name = f'name "{name}"'
+							name = _bytes_escape(res.name, quote='"')
-					
+							name = f'name "{name}"'
-					attrs = _decompose_flags(res.attributes)
+						
-					if attrs:
+						attrs = _decompose_flags(res.attributes)
-						attrdesc = " | ".join(attr.name for attr in attrs)
+						if attrs:
-					else:
+							attrdesc = " | ".join(attr.name for attr in attrs)
-						attrdesc = "no attributes"
+						else:
-					
+							attrdesc = "no attributes"
-					print(f"({resid}), {name}, {attrdesc}, {len(res.data)} bytes")
+						
-				print()
+						print(f"({resid}), {name}, {attrdesc}, {len(res.data)} bytes")
+					print()
+			else:
+				print("No resource types (empty resource file)")
 	
 	sys.exit(0)
 

setup.py

@@ -7,7 +7,7 @@ with open("README.rst", "r", encoding="utf-8") as f:
 
 setuptools.setup(
 	name="rsrcfork",
-	version="1.1.0",
+	version="1.1.1",
 	description="A pure Python library for reading old Macintosh resource manager data",
 	long_description=long_description,
 	url="https://github.com/dgelessus/python-rsrcfork",
@@ -26,5 +26,6 @@ setuptools.setup(
 		"Programming Language :: Python :: 3.6",
 	],
 	keywords="rsrc fork resource manager macintosh mac macos",
+	python_requires=">=3.6",
 	py_modules=["rsrcfork"],
 )