def nsData2bytes(ns, dflt=b''): # XXX an NSData method?
'''Create Python C{bytes} from C{NSData}.
@param ns: The C{NSData} (L{ObjCInstance}).
@keyword dflt: Default for empty C{NSData} (C{bytes}).
@return: The bytes (C{bytes}) or I{dflt}.
'''
isObjCInstanceOf(ns, NSData, name='ns')
n = ns.length()
if n:
buf = (c_byte * n)()
ns.getBytes_length_(byref(buf), n)
return b''.join(iterbytes(buf[:n]))
return dflt
def split_encoding(encoding): # MCCABE 18
'''Split a type encoding into separate type encodings.
Does not handle C{bitfield}s, C{array}s, C{struct}s, C{union}s,
etc. and strips any offset, size or width specifiers from the
encoding.
@return: The individual type encodings (C{list}).
@raise TypeCodeError: Invalid or unbalanced I{encoding}.
@example:
>>> split_encoding('^v16@0:8')
>>> ['^v', '@', ':']
>>> split_encoding('{CGSize=dd}40@0:8{PyObject=@}Q32')
>>> ['{CGSize=dd}', '@', ':', '{PyObject=@}', 'Q']
Supported Type Encodings:
- B = bool (C++ bool, C99 _Bool)
- c, C = char, unsigned char
- f, d = float, double
- i, I = int, unsigned int
- l, L = long, unsigned long (32-bit in 64-bit Apps)
- q, Q = long long, unsigned long long
- s, S = short, unsigned short
- t, T = 128-bit int, unsigned int
- v = void
- * = string (char *)
- : = method selector C{SEL/cmd}
- # = class
- #"name" = class "name"
- @ = object instance C{Id/self} or statically typed
- @"name" = instance C{Id/self} of class "name"
- ^type = pointer to type
- ? = unknown type (among other things, used for function pointers)
PyCocoa specific:
- P = Python object, shorthand for C{PyObjectEncoding}
Unsupported Type Encodings:
- bW = bitfield of width W
- [Ltype] = array of L items of type
- E{lb}name=type...E{rb} = structure
- (name=type...) = union
- <...> = block
- ?<...> = block with signature
Unknown or for ObjC internal use:
- A = ?
- j = ?
- n, N = in, inout
- o, O = out, bycopy
- r, R = const, byref
- V = oneway
@note: Type encodings may be preceeded by C{"name"}, for example a
C{bitfield} C{"name"b1}, C{struct} items C{E{lb}CGsize="width"d"heigth"dE{rb}},
C{union} items, etc. and all such C{"name"} prefixes are ignored.
@see: U{Type Encodings<https://Developer.Apple.com/library/content/documentation/
Cocoa/Conceptual/ObjCRuntimeGuide/Articles/ocrtTypeEncodings.html>},
U{NSHipster Type Encodings<https://NSHipster.com/type-encodings>} and
U{Digits in type encoding<https://StackOverflow.com/questions/11527385/
how-are-the-digits-in-objc-method-type-encoding-calculated>}.
'''
code = []
codes = []
opened = [] # opened braces, brackets, parensm etc.
quoted = False # inside double quotes
for b in iterbytes(str2bytes(encoding)):
if b in _TYPEOPENERS:
if code and code[-1] != b'^' and not opened:
codes.append(_join(code))
code = []
opened.append(_TYPE2CLOSER[b])
code.append(b)
elif b in _TYPECLOSERS:
code.append(b)
if not opened or b != opened.pop():
raise TypeCodeError('encoding %s: %r' % ('unbalanced',
bytes2str(_join(code))))
if not opened:
codes.append(_join(code))
code = []
elif opened: # inside braces, etc
# XXX ignore digits?
code.append(b) # stick anything on
elif b == b'"':
code.append(b)
if quoted: # closing quotes
code = _join(code)
if code[:2] in (b'@"', b'#"'):
# XXX only @"..." and #"..." are OK
# XXX what about ^@"..." and ^#"..."?
codes.append(code)
elif code[:1] == b'"':
pass # ignore prefix "name"
else:
raise TypeCodeError('encoding %s: %r' % ('invalid',
bytes2str(code)))
code = []
quoted = not quoted
elif quoted: # inside quotes
# XXX only alphanumeric, '_', '.'?
code.append(b) # stick anything on
elif b in _TYPECODESET:
if code and code[-1] != b'^':
# not a pointer, previous char != '^'
codes.append(_join(code))
code = []
code.append(b)
elif b in _TYPESKIPPED:
pass # ignore type, width and offsets
if opened:
raise TypeCodeError('encoding %s: %r' % ('unbalanced', bytes2str(encoding)))
if code: # final type code
codes.append(_join(code))
return codes
@example:
>>> split_emcoding2('v*')
>>> (['v', '@', ':', '*'], 'v@:*')
'''
codes = split_encoding(encoding)
if codes[1:3] != [b'@', b':']:
# Add codes for hidden arguments
codes.insert(1, b'@') # Id/self type encoding
codes.insert(2, b':') # SEL/cmd type encoding
return codes[start:], _join(codes)
_TYPECODESET = set(iterbytes(b'cCiIsSlLqQfdBvP*@#:b^?')) # _emcoding2ctype.keys()
_TYPESKIPPED = set(iterbytes(b'0123456789 nNoOrRV')) # type, width and offsets
_TYPE2CLOSER = {b'{': b'}', b'[': b']', b'(': b')', b'<': b'>'}
_TYPE2OPENER = dict(reversed(_) for _ in _TYPE2CLOSER.items())
_TYPEOPENERS = set(_TYPE2CLOSER.keys())
_TYPECLOSERS = set(_TYPE2CLOSER.values())
def split_encoding(encoding): # MCCABE 18
'''Split a type encoding into separate type encodings.
Does not handle C{bitfield}s, C{array}s, C{struct}s, C{union}s,
etc. and strips any offset, size or width specifiers from the
encoding.