EVOLUTION-MANAGER

Edit File: whatsnew.txt

====================== What's New ====================== v1.9 ==== * Structs with variable-sized arrays as their last field: now we track the length of the array after ``ffi.new()`` is called, just like we always tracked the length of ``ffi.new("int[]", 42)``. This lets us detect out-of-range accesses to array items. This also lets us display a better ``repr()``, and have the total size returned by ``ffi.sizeof()`` and ``ffi.buffer()``. Previously both functions would return a result based on the size of the declared structure type, with an assumed empty array. (Thanks andrew for starting this refactoring.) * Add support in ``cdef()/set_source()`` for unspecified-length arrays in typedefs: ``typedef int foo_t[...];``. It was already supported for global variables or structure fields. * I turned in v1.8 a warning from ``cffi/model.py`` into an error: ``'enum xxx' has no values explicitly defined: refusing to guess which integer type it is meant to be (unsigned/signed, int/long)``. Now I'm turning it back to a warning again; it seems that guessing that the enum has size ``int`` is a 99%-safe bet. (But not 100%, so it stays as a warning.) * Fix leaks in the code handling ``FILE *`` arguments. In CPython 3 there is a remaining issue that is hard to fix: if you pass a Python file object to a ``FILE *`` argument, then ``os.dup()`` is used and the new file descriptor is only closed when the GC reclaims the Python file object---and not at the earlier time when you call ``close()``, which only closes the original file descriptor. If this is an issue, you should avoid this automatic convertion of Python file objects: instead, explicitly manipulate file descriptors and call ``fdopen()`` from C (...via cffi). v1.8.3 ====== * When passing a ``void *`` argument to a function with a different pointer type, or vice-versa, the cast occurs automatically, like in C. The same occurs for initialization with ``ffi.new()`` and a few other places. However, I thought that ``char *`` had the same property---but I was mistaken. In C you get the usual warning if you try to give a ``char *`` to a ``char **`` argument, for example. Sorry about the confusion. This has been fixed in CFFI by giving for now a warning, too. It will turn into an error in a future version. v1.8.2 ====== * Issue #283: fixed ``ffi.new()`` on structures/unions with nested anonymous structures/unions, when there is at least one union in the mix. When initialized with a list or a dict, it should now behave more closely like the ``{ }`` syntax does in GCC. v1.8.1 ====== * CPython 3.x: experimental: the generated C extension modules now use the "limited API", which means that, as a compiled .so/.dll, it should work directly on any version of CPython >= 3.2. The name produced by distutils is still version-specific. To get the version-independent name, you can rename it manually to ``NAME.abi3.so``, or use the very recent setuptools 26. * Added ``ffi.compile(debug=...)``, similar to ``python setup.py build --debug`` but defaulting to True if we are running a debugging version of Python itself. v1.8 ==== * Removed the restriction that ``ffi.from_buffer()`` cannot be used on byte strings. Now you can get a ``char *`` out of a byte string, which is valid as long as the string object is kept alive. (But don't use it to *modify* the string object! If you need this, use ``bytearray`` or other official techniques.) * PyPy 5.4 can now pass a byte string directly to a ``char *`` argument (in older versions, a copy would be made). This used to be a CPython-only optimization. v1.7 ==== * ``ffi.gc(p, None)`` removes the destructor on an object previously created by another call to ``ffi.gc()`` * ``bool(ffi.cast("primitive type", x))`` now returns False if the value is zero (including ``-0.0``), and True otherwise. Previously this would only return False for cdata objects of a pointer type when the pointer is NULL. * bytearrays: ``ffi.from_buffer(bytearray-object)`` is now supported. (The reason it was not supported was that it was hard to do in PyPy, but it works since PyPy 5.3.) To call a C function with a ``char *`` argument from a buffer object---now including bytearrays---you write ``lib.foo(ffi.from_buffer(x))``. Additionally, this is now supported: ``p[0:length] = bytearray-object``. The problem with this was that a iterating over bytearrays gives *numbers* instead of *characters*. (Now it is implemented with just a memcpy, of course, not actually iterating over the characters.) * C++: compiling the generated C code with C++ was supposed to work, but failed if you make use the ``bool`` type (because that is rendered as the C ``_Bool`` type, which doesn't exist in C++). * ``help(lib)`` and ``help(lib.myfunc)`` now give useful information, as well as ``dir(p)`` where ``p`` is a struct or pointer-to-struct. v1.6 ==== * `ffi.list_types()`_ * `ffi.unpack()`_ * `extern "Python+C"`_ * in API mode, ``lib.foo.__doc__`` contains the C signature now. On CPython you can say ``help(lib.foo)``, but for some reason ``help(lib)`` (or ``help(lib.foo)`` on PyPy) is still useless; I haven't yet figured out the hacks needed to convince ``pydoc`` to show more. (You can use ``dir(lib)`` but it is not most helpful.) * Yet another attempt at robustness of ``ffi.def_extern()`` against CPython's interpreter shutdown logic. .. _`ffi.list_types()`: ref.html#ffi-list-types .. _`ffi.unpack()`: ref.html#ffi-unpack .. _`extern "Python+C"`: using.html#extern-python-c v1.5.2 ====== * Fix 1.5.1 for Python 2.6. v1.5.1 ====== * A few installation-time tweaks (thanks Stefano!) * Issue #245: Win32: ``__stdcall`` was never generated for ``extern "Python"`` functions * Issue #246: trying to be more robust against CPython's fragile interpreter shutdown logic v1.5.0 ====== * Support for `using CFFI for embedding`__. .. __: embedding.html v1.4.2 ====== Nothing changed from v1.4.1. v1.4.1 ====== * Fix the compilation failure of cffi on CPython 3.5.0. (3.5.1 works; some detail changed that makes some underscore-starting macros disappear from view of extension modules, and I worked around it, thinking it changed in all 3.5 versions---but no: it was only in 3.5.1.) v1.4.0 ====== * A `better way to do callbacks`__ has been added (faster and more portable, and usually cleaner). It is a mechanism for the out-of-line API mode that replaces the dynamic creation of callback objects (i.e. C functions that invoke Python) with the static declaration in ``cdef()`` of which callbacks are needed. This is more C-like, in that you have to structure your code around the idea that you get a fixed number of function pointers, instead of creating them on-the-fly. * ``ffi.compile()`` now takes an optional ``verbose`` argument. When ``True``, distutils prints the calls to the compiler. * ``ffi.compile()`` used to fail if given ``sources`` with a path that includes ``".."``. Fixed. * ``ffi.init_once()`` added. See docs__. * ``dir(lib)`` now works on libs returned by ``ffi.dlopen()`` too. * Cleaned up and modernized the content of the ``demo`` subdirectory in the sources (thanks matti!). * ``ffi.new_handle()`` is now guaranteed to return unique ``void *`` values, even if called twice on the same object. Previously, in that case, CPython would return two ``cdata`` objects with the same ``void *`` value. This change is useful to add and remove handles from a global dict (or set) without worrying about duplicates. It already used to work like that on PyPy. *This change can break code that used to work on CPython by relying on the object to be kept alive by other means than keeping the result of ffi.new_handle() alive.* (The corresponding `warning in the docs`__ of ``ffi.new_handle()`` has been here since v0.8!) .. __: using.html#extern-python .. __: ref.html#ffi-init-once .. __: ref.html#ffi-new-handle v1.3.1 ====== * The optional typedefs (``bool``, ``FILE`` and all Windows types) were not always available from out-of-line FFI objects. * Opaque enums are phased out from the cdefs: they now give a warning, instead of (possibly wrongly) being assumed equal to ``unsigned int``. Please report if you get a reasonable use case for them. * Some parsing details, notably ``volatile`` is passed along like ``const`` and ``restrict``. Also, older versions of pycparser mis-parse some pointer-to-pointer types like ``char * const *``: the "const" ends up at the wrong place. Added a workaround. v1.3.0 ====== * Added `ffi.memmove()`_. * Pull request #64: out-of-line API mode: we can now declare floating-point types with ``typedef float... foo_t;``. This only works if ``foo_t`` is a float or a double, not ``long double``. * Issue #217: fix possible unaligned pointer manipulation, which crashes on some architectures (64-bit, non-x86). * Issues #64 and #126: when using ``set_source()`` or ``verify()``, the ``const`` and ``restrict`` keywords are copied from the cdef to the generated C code; this fixes warnings by the C compiler. It also fixes corner cases like ``typedef const int T; T a;`` which would previously not consider ``a`` as a constant. (The cdata objects themselves are never ``const``.) * Win32: support for ``__stdcall``. For callbacks and function pointers; regular C functions still don't need to have their `calling convention`_ declared. * Windows: CPython 2.7 distutils doesn't work with Microsoft's official Visual Studio for Python, and I'm told this is `not a bug`__. For ffi.compile(), we `removed a workaround`__ that was inside cffi but which had unwanted side-effects. Try saying ``import setuptools`` first, which patches distutils... .. _`ffi.memmove()`: ref.html#ffi-memmove .. __: https://bugs.python.org/issue23246 .. __: https://bitbucket.org/cffi/cffi/pull-requests/65/remove-_hack_at_distutils-which-imports/diff .. _`calling convention`: using.html#windows-calling-conventions v1.2.1 ====== Nothing changed from v1.2.0. v1.2.0 ====== * Out-of-line mode: ``int a[][...];`` can be used to declare a structure field or global variable which is, simultaneously, of total length unknown to the C compiler (the ``a[]`` part) and each element is itself an array of N integers, where the value of N *is* known to the C compiler (the ``int`` and ``[...]`` parts around it). Similarly, ``int a[5][...];`` is supported (but probably less useful: remember that in C it means ``int (a[5])[...];``). * PyPy: the ``lib.some_function`` objects were missing the attributes ``__name__``, ``__module__`` and ``__doc__`` that are expected e.g. by some decorators-management functions from ``functools``. * Out-of-line API mode: you can now do ``from _example.lib import x`` to import the name ``x`` from ``_example.lib``, even though the ``lib`` object is not a standard module object. (Also works in ``from _example.lib import *``, but this is even more of a hack and will fail if ``lib`` happens to declare a name called ``__all__``. Note that ``*`` excludes the global variables; only the functions and constants make sense to import like this.) * ``lib.__dict__`` works again and gives you a copy of the dict---assuming that ``lib`` has got no symbol called precisely ``__dict__``. (In general, it is safer to use ``dir(lib)``.) * Out-of-line API mode: global variables are now fetched on demand at every access. It fixes issue #212 (Windows DLL variables), and also allows variables that are defined as dynamic macros (like ``errno``) or ``__thread`` -local variables. (This change might also tighten the C compiler's check on the variables' type.) * Issue #209: dereferencing NULL pointers now raises RuntimeError instead of segfaulting. Meant as a debugging aid. The check is only for NULL: if you dereference random or dead pointers you might still get segfaults. * Issue #152: callbacks__: added an argument ``ffi.callback(..., onerror=...)``. If the main callback function raises an exception and ``onerror`` is provided, then ``onerror(exception, exc_value, traceback)`` is called. This is similar to writing a ``try: except:`` in the main callback function, but in some cases (e.g. a signal) an exception can occur at the very start of the callback function---before it had time to enter the ``try: except:`` block. * Issue #115: added ``ffi.new_allocator()``, which officializes support for `alternative allocators`__. .. __: using.html#callbacks .. __: ref.html#ffi-new-allocator v1.1.2 ====== * ``ffi.gc()``: fixed a race condition in multithreaded programs introduced in 1.1.1 v1.1.1 ====== * Out-of-line mode: ``ffi.string()``, ``ffi.buffer()`` and ``ffi.getwinerror()`` didn't accept their arguments as keyword arguments, unlike their in-line mode equivalent. (It worked in PyPy.) * Out-of-line ABI mode: documented a restriction__ of ``ffi.dlopen()`` when compared to the in-line mode. * ``ffi.gc()``: when called several times with equal pointers, it was accidentally registering only the last destructor, or even none at all depending on details. (It was correctly registering all of them only in PyPy, and only with the out-of-line FFIs.) .. __: cdef.html#dlopen-note v1.1.0 ====== * Out-of-line API mode: we can now declare integer types with ``typedef int... foo_t;``. The exact size and signedness of ``foo_t`` is figured out by the compiler. * Out-of-line API mode: we can now declare multidimensional arrays (as fields or as globals) with ``int n[...][...]``. Before, only the outermost dimension would support the ``...`` syntax. * Out-of-line ABI mode: we now support any constant declaration, instead of only integers whose value is given in the cdef. Such "new" constants, i.e. either non-integers or without a value given in the cdef, must correspond to actual symbols in the lib. At runtime they are looked up the first time we access them. This is useful if the library defines ``extern const sometype somename;``. * ``ffi.addressof(lib, "func_name")`` now returns a regular cdata object of type "pointer to function". You can use it on any function from a library in API mode (in ABI mode, all functions are already regular cdata objects). To support this, you need to recompile your cffi modules. * Issue #198: in API mode, if you declare constants of a ``struct`` type, what you saw from lib.CONSTANT was corrupted. * Issue #196: ``ffi.set_source("package._ffi", None)`` would incorrectly generate the Python source to ``package._ffi.py`` instead of ``package/_ffi.py``. Also fixed: in some cases, if the C file was in ``build/foo.c``, the .o file would be put in ``build/build/foo.o``. v1.0.3 ====== * Same as 1.0.2, apart from doc and test fixes on some platforms. v1.0.2 ====== * Variadic C functions (ending in a "..." argument) were not supported in the out-of-line ABI mode. This was a bug---there was even a (non-working) example__ doing exactly that! .. __: overview.html#out-of-line-abi-level v1.0.1 ====== * ``ffi.set_source()`` crashed if passed a ``sources=[..]`` argument. Fixed by chrippa on pull request #60. * Issue #193: if we use a struct between the first cdef() where it is declared and another cdef() where its fields are defined, then this definition was ignored. * Enums were buggy if you used too many "..." in their definition. v1.0.0 ====== * The main news item is out-of-line module generation: * `for ABI level`_, with ``ffi.dlopen()`` * `for API level`_, which used to be with ``ffi.verify()``, now deprecated * (this page will list what is new from all versions from 1.0.0 forward.) .. _`for ABI level`: overview.html#out-of-line-abi-level .. _`for API level`: overview.html#out-of-line-api-level