MakeHFS: write to pre-existing partitioned disks

README.md

@@ -7,7 +7,7 @@ codes](https://en.wikipedia.org/wiki/Creator_code) are first-class
 citizens.
 
 Python interface
-----------------
+================
 The Python API is simple. The contents of a `Volume` or a `Folder` are
 accessed using the index operator `[]`. While working on a filesystem,
 its entire high-level contents are stored in memory as a Python object.
@@ -42,7 +42,7 @@ with open('FloppyImage.dsk', 'rb') as f:
 ```
 
 Command-line interface
-----------------------
+======================
 This package also installs the `MakeHFS` and `DumpHFS` utilities, for
 working with folders on your native filesystem. Briefly, resource forks
 are stored in Rez-formatted `.rdump` files, and type and creator codes
@@ -56,7 +56,7 @@ Mac OS Roman encoding with Mac-style (CR) line endings.
 Both commands have a `--help` argument to display their options.
 
 Why?
-----
+====
 I want an automated, reproducible way to compile legacy MacOS software.
 Without any current operating system fully supporting HFS,
 [libhfs/hfsutils](https://www.mars.org/home/rob/proj/hfs/) (a C library
@@ -71,3 +71,11 @@ high-level programming language seemed like a reasonable tradeoff. As a
 result, `machfs` has nearly an order of magnitude fewer lines than
 `libhfs`, and is more maintainable, at a nearly negligible cost in
 performance.
+
+Changes
+=======
+1.3
+---
+- Sam Fuller's btree fix for volumes with *many* files:
+  https://github.com/elliotnunn/machfs/commit/b44a2f9
+- Support for Aliases, represented in the native FS as symlinks

bin/DumpHFS

@@ -2,6 +2,7 @@
 
 import argparse
 from machfs import Volume
+import os
 
 args = argparse.ArgumentParser()
 
@@ -10,6 +11,11 @@ args.add_argument('dir', metavar='OUTPUT', nargs=1, help='Destination folder')
 
 args = args.parse_args()
 
+try:
+    os.mkdir(args.dir[0])
+except FileExistsError:
+    pass
+
 with open(args.src[0], 'rb') as f:
 	v = Volume()
 	v.read(f.read())

bin/MakeHFS

@@ -123,17 +123,62 @@ vol.name = args.name
 
 if args.dir: vol.read_folder(args.dir, date=args.date, mpw_dates=args.mpw_dates)
 
-with open(args.dest[0], 'ab+') as f:
-    if args.size is None: args.size = hack_file_size(f)
-    if args.size == 0: args.size = 800 * 1024
+try:
+    f = open(args.dest[0], 'rb+')
+    existed = True
+except FileNotFoundError:
+    f = open(args.dest[0], 'wb+')
+    existed = False
 
-with open(args.dest[0], 'rb+') as f:
-    left, gap, right = vol.write(args.size, startapp=args.app, sparse=True)
+if args.size is not None:
+    offset = 0
+    size = args.size
+    trunc = True
+    nameoffset = None
 
-    f.write(left)
-    f.seek(gap, 1)
-    problem = len(left) + gap - f.tell()
-    if problem > 0:
-        f.write(bytes(problem))
-    f.write(right)
-    f.truncate()
+elif not existed: # make a tiny floppy
+    offset = 0
+    size = 800 * 1024
+    trunc = True
+    nameoffset = None
+
+elif f.read(2) == b'ER': # is partitioned disk
+    blksize = int.from_bytes(f.read(2), byteorder='big')
+    f.seek(blksize + 4)
+    entrycnt = int.from_bytes(f.read(4), byteorder='big')
+
+    for i in range(entrycnt):
+        entryoffset = blksize * (i + 1)
+        f.seek(entryoffset + 48)
+        if f.read(10) == b'Apple_HFS\x00':
+            f.seek(entryoffset + 8)
+            offset = blksize * int.from_bytes(f.read(4), byteorder='big')
+            size = blksize * int.from_bytes(f.read(4), byteorder='big')
+            trunc = False
+            nameoffset = entryoffset + 16
+            break
+    else:
+        raise ValueError("No HFS partition in this map")
+
+else: # is raw filesystem
+    offset = 0
+    size = hack_file_size(f)
+    trunc = False
+
+left, gap, right = vol.write(size, startapp=args.app, sparse=True)
+
+f.seek(offset)
+f.write(left)
+f.seek(gap, 1)
+problem = len(left) + gap - f.tell()
+if problem > 0:
+    f.write(bytes(problem))
+f.write(right)
+
+if nameoffset is not None:
+    f.seek(nameoffset)
+    f.write(args.name.encode('mac_roman').ljust(32, b'\x00'))
+
+
+
+if trunc: f.truncate()

machfs/directory.py

@@ -2,7 +2,7 @@ from collections.abc import MutableMapping
 import os
 from os import path
 from macresources import make_rez_code, parse_rez_code, make_file, parse_file
-from warnings import warn
+import sys
 
 
 TEXT_TYPES = [b'TEXT', b'ttro'] # Teach Text read-only
@@ -267,7 +267,7 @@ class AbstractFolder(MutableMapping):
             blacklist_test = ':'.join(p) + ':'
             if blacklist_test.startswith(tuple(blacklist)): continue
             if _unsyncability(p[-1]):
-                warn('Ignoring unsyncable name: %r' % (':' + ':'.join(p)))
+                print('Ignoring unsyncable name: %r' % (':' + ':'.join(p)), file=sys.stderr)
                 blacklist.append(blacklist_test)
                 continue
 
@@ -293,11 +293,17 @@ class AbstractFolder(MutableMapping):
 
                 # write a resource dump iff that fork has any bytes (dump may still be empty)
                 if obj.rsrc:
-                    with open(rsrc_path, 'wb') as f:
+                    try:
                         rdump = make_rez_code(parse_file(obj.rsrc), ascii_clean=True)
-                        f.write(rdump)
+                    except:
+                        with open(nativepath + '.rdump.corrupt', 'wb') as f:
+                            f.write(obj.rsrc)
+                        print('Dumping corrupt resource fork: %r' % (':' + ':'.join(p)), file=sys.stderr)
+                    else:
+                        with open(rsrc_path, 'wb') as f:
+                            f.write(rdump)
                 else:
-                     _try_delete(rsrc_path)   
+                     _try_delete(rsrc_path)
 
                 # write an info dump iff either field is non-null
                 idump = obj.type + obj.creator

setup.py

@@ -2,7 +2,7 @@ from setuptools import setup
 
 setup(
     name='machfs',
-    version='1.2.4',
+    version='1.3',
     author='Elliot Nunn',
     author_email='elliotnunn@me.com',
     description='Library for reading and writing Macintosh HFS volumes',