initial attempt with ctypes

send2trash/plat_osx.py

@@ -6,18 +6,21 @@
 
 from __future__ import unicode_literals
 
-from ctypes import cdll, byref, Structure, c_char, c_char_p
+from ctypes import cdll, byref, Structure, c_char, c_char_p, c_void_p, c_int64, sizeof
 from ctypes.util import find_library
 
 from .compat import binary_type
 
 Foundation = cdll.LoadLibrary(find_library('Foundation'))
 CoreServices = cdll.LoadLibrary(find_library('CoreServices'))
+objc = cdll.LoadLibrary(find_library('objc'))
 
 GetMacOSStatusCommentString = Foundation.GetMacOSStatusCommentString
 GetMacOSStatusCommentString.restype = c_char_p
 FSPathMakeRefWithOptions = CoreServices.FSPathMakeRefWithOptions
 FSMoveObjectToTrashSync = CoreServices.FSMoveObjectToTrashSync
+AEGetParamDesc = CoreServices.AEGetParamDesc
+AESendMessage = CoreServices.AESendMessage
 
 kFSPathMakeRefDefaultOptions = 0
 kFSPathMakeRefDoNotFollowLeafSymlink = 0x01
@@ -36,9 +39,12 @@ def check_op_result(op_result):
         msg = GetMacOSStatusCommentString(op_result).decode('utf-8')
         raise OSError(msg)
 
-def send2trash(path):
+def send2trash(path, with_put_back=False):
     if not isinstance(path, binary_type):
         path = path.encode('utf-8')
+    _with_put_back(path) if with_put_back else _normally(path)
+
+def _normally(path):
     fp = FSRef()
     opts = kFSPathMakeRefDoNotFollowLeafSymlink
     op_result = FSPathMakeRefWithOptions(path, opts, byref(fp), None)
@@ -46,3 +52,106 @@ def send2trash(path):
     opts = kFSFileOperationDefaultOptions
     op_result = FSMoveObjectToTrashSync(byref(fp), None, opts)
     check_op_result(op_result)
+
+# Everything below here is required for getting the "put back" feature
+# in the macOS trash - we attempt to ask Finder the trash the file for us.
+
+objc.objc_getClass.restype = c_void_p
+objc.sel_registerName.restype = c_void_p
+objc.objc_msgSend.restype = c_void_p
+objc.objc_msgSend.argtypes = [c_void_p, c_void_p]
+
+_msg = objc.objc_msgSend
+_cls = objc.objc_getClass
+_sel = objc.sel_registerName
+
+kAEWaitReply = 0x3
+kAnyTransactionID = 0
+kAEDefaultTimeout = -1
+kAutoGenerateReturnID = -1
+NSUTF8StringEncoding = 0x4
+
+# TODO: this is probably incorrect/or changes depending on arch, etc
+typeKernelProcessID = 0x6b706964
+
+# TODO: not sure exactly what these should be
+keyDirectObject = '----'
+typeWildCard = '****'
+
+class AEDataStorage(Structure):
+    _fields_ = []
+
+# AppleEvent seems to be an alias of AEDesc
+class AEDesc(Structure):
+    # DescType is an unsigned int ?
+    # AEDataStorage is something else ?
+    _fields_ = [('descriptorType', c_int64), ('dataHandle', AEDataStorage)]
+
+# This was inspired by https://github.com/ali-rantakari/trash.
+# See https://github.com/ali-rantakari/trash/blob/master/trash.m#L263-L341
+# and also https://stackoverflow.com/a/1490644/5552584.
+def _with_put_back(path):
+    # Create an autorelease pool.
+    NSAutoreleasePool = _cls('NSAutoreleasePool')
+    pool = _msg(NSAutoreleasePool, _sel('alloc'))
+    pool = _msg(pool, _sel('init'))
+
+    try:
+        # Generate list descriptor containing the file URL
+        NSAppleEventDescriptor = _cls('NSAppleEventDescriptor')
+        url_list_descr = _msg(NSAppleEventDescriptor, _sel('listDescriptor'))
+        url = _msg(_cls('NSURL'), _sel('fileURLWithPath'), path)
+        url_str = _msg(url, _sel('absoluteString'))
+        data = _msg(url_str, _sel('dataUsingEncoding:'), NSUTF8StringEncoding)
+        descr = _msg(NSAppleEventDescriptor,
+            _sel('descriptorWithDescriptorType:'), 'furl',
+            _sel('data:'), data)
+        _msg(url_list_descr,
+            _sel('insertDescriptor:'), descr,
+            _sel('atIndex:'), 1)
+
+        # Generate the 'top level' "delete" descriptor
+        finder_pid = _get_finder_pid()
+        target_descr = _msg(NSAppleEventDescriptor,
+            _sel('descriptorWithDescriptorType:'), typeKernelProcessID,
+            _sel('bytes:'), byref(finder_pid),
+            _sel('length:'), sizeof(finder_pid))
+        descriptor = _msg(NSAppleEventDescriptor,
+            _sel('appleEventWithEventClass:'), 'core',
+            _sel('eventID:'), 'delo',
+            _sel('targetDescriptor:'), target_descr,
+            _sel('returnID:'), kAutoGenerateReturnID,
+            _sel('transactionID:'), kAnyTransactionID)
+
+        # add the list of file URLs as argument
+        _msg(descriptor,
+            _sel('setDescriptor:'), url_list_descr,
+            _sel('forKeyword:'), '----')
+
+        # send the Apple Event synchronously
+        reply_event = AEDesc()
+        op_result = AESendMessage(_msg(descriptor, _sel('asDesc')),
+            byref(reply_event), kAEWaitReply, kAEDefaultTimeout)
+        check_op_result(op_result)
+
+        # check reply in order to determine return value
+        reply_ae_descr = AEDesc()
+        op_result = AEGetParamDesc(byref(reply_event), keyDirectObject,
+            typeWildCard, byref(reply_ae_descr))
+        check_op_result(op_result)
+
+        reply_descr = _msg(_msg(_msg(NSAppleEventDescriptor, _sel('alloc')),
+            _sel('initWithAEDescNoCopy:'), byref(reply_ae_descr)), _sel('autorelease'))
+
+        if _msg(reply_descr, _sel('numberOfItems')) == 0:
+            raise Exception('file could not be trashed')
+    finally:
+        _msg(pool, _sel('release'))
+
+def _get_finder_pid():
+    import subprocess
+    child = subprocess.Popen(['pgrep', '-f', 'Finder'],
+        stdout=subprocess.PIPE, shell=False)
+    response = child.communicate()[0]
+    # TODO: assumed that pid_t is a c_int64 (should depend on arch)
+    return c_int64(int(response.split()[0]))