The purpose of the `unicodedata.is_normalized` function is to answer
the question `str == unicodedata.normalized(form, str)` more
efficiently than writing just that, by using the "quick check"
optimization described in the Unicode standard in UAX #15.
However, it turns out the code doesn't implement the full algorithm
from the standard, and as a result we often miss the optimization and
end up having to compute the whole normalized string after all.
Implement the standard's algorithm. This greatly speeds up
`unicodedata.is_normalized` in many cases where our partial variant
of quick-check had been returning MAYBE and the standard algorithm
returns NO.
At a quick test on my desktop, the existing code takes about 4.4 ms/MB
(so 4.4 ns per byte) when the partial quick-check returns MAYBE and it
has to do the slow normalize-and-compare:
$ build.base/python -m timeit -s 'import unicodedata; s = "\uf900"*500000' \
-- 'unicodedata.is_normalized("NFD", s)'
50 loops, best of 5: 4.39 msec per loop
With this patch, it gets the answer instantly (58 ns) on the same 1 MB
string:
$ build.dev/python -m timeit -s 'import unicodedata; s = "\uf900"*500000' \
-- 'unicodedata.is_normalized("NFD", s)'
5000000 loops, best of 5: 58.2 nsec per loop
This restores a small optimization that the original version of this
code had for the `unicodedata.normalize` use case.
With this, that case is actually faster than in master!
$ build.base/python -m timeit -s 'import unicodedata; s = "\u0338"*500000' \
-- 'unicodedata.normalize("NFD", s)'
500 loops, best of 5: 561 usec per loop
$ build.dev/python -m timeit -s 'import unicodedata; s = "\u0338"*500000' \
-- 'unicodedata.normalize("NFD", s)'
500 loops, best of 5: 512 usec per loop
* Use the 'p' format unit instead of manually called PyObject_IsTrue().
* Pass boolean value instead 0/1 integers to functions that needs boolean.
* Convert some arguments to boolean only once.
Fix a ctypes regression of Python 3.8. When a ctypes.Structure is
passed by copy to a function, ctypes internals created a temporary
object which had the side effect of calling the structure finalizer
(__del__) twice. The Python semantics requires a finalizer to be
called exactly once. Fix ctypes internals to no longer call the
finalizer twice.
Create a new internal StructParam_Type which is only used by
_ctypes_callproc() to call PyMem_Free(ptr) on Py_DECREF(argument).
StructUnionType_paramfunc() creates such object.
bpo-37834: Normalise handling of reparse points on Windows
* ntpath.realpath() and nt.stat() will traverse all supported reparse points (previously was mixed)
* nt.lstat() will let the OS traverse reparse points that are not name surrogates (previously would not traverse any reparse point)
* nt.[l]stat() will only set S_IFLNK for symlinks (previous behaviour)
* nt.readlink() will read destinations for symlinks and junction points only
bpo-1311: os.path.exists('nul') now returns True on Windows
* nt.stat('nul').st_mode is now S_IFCHR (previously was an error)
The faulthandler module no longer allocates its alternative stack at
Python startup. Now the stack is only allocated at the first
faulthandler usage.
faulthandler no longer ignores memory allocation failure when
allocating the stack. sigaltstack() failure now raises an OSError
exception, rather than being ignored.
The alternative stack is no longer used if sigaction() is
not available. In practice, sigaltstack() should only be available
when sigaction() is avaialble, so this change should have no effect
in practice.
faulthandler.dump_traceback_later() internal locks are now only
allocated at the first dump_traceback_later() call, rather than
always being allocated at Python startup.
There are plenty of legitimate scripts in the tree that begin with a
`#!`, but also a few that seem to be marked executable by mistake.
Found them with this command -- it gets executable files known to Git,
filters to the ones that don't start with a `#!`, and then unmarks
them as executable:
$ git ls-files --stage \
| perl -lane 'print $F[3] if (!/^100644/)' \
| while read f; do
head -c2 "$f" | grep -qxF '#!' \
|| chmod a-x "$f"; \
done
Looking at the list by hand confirms that we didn't sweep up any
files that should have the executable bit after all. In particular
* The `.psd` files are images from Photoshop.
* The `.bat` files sure look like things that can be run.
But we have lots of other `.bat` files, and they don't have
this bit set, so it must not be needed for them.
Automerge-Triggered-By: @benjaminp
X509_AUX is an odd, note widely used, OpenSSL extension to the X509 file format. This function doesn't actually use any of the extra metadata that it parses, so just use the standard API.
Automerge-Triggered-By: @tiran
faulthandler now allocates a dedicated stack of SIGSTKSZ*2 bytes,
instead of just SIGSTKSZ bytes. Calling the previous signal handler
in faulthandler signal handler uses more than SIGSTKSZ bytes of stack
memory on some platforms.
FreeBSD implementation of poll(2) restricts the timeout argument to be
either zero, or positive, or equal to INFTIM (-1).
Unless otherwise overridden, socket timeout defaults to -1. This value
is then converted to milliseconds (-1000) and used as argument to the
poll syscall. poll returns EINVAL (22), and the connection fails.
This bug was discovered during the EINTR handling testing, and the
reproduction code can be found in
https://bugs.python.org/issue23618 (see connect_eintr.py,
attached). On GNU/Linux, the example runs as expected.
This change is trivial:
If the supplied timeout value is negative, truncate it to -1.
This fixes an inconsistency between the Python and C implementations of
the datetime module. The pure python version of the code was not
accepting offsets greater than 23:59 but less than 24:00. This is an
accidental legacy of the original implementation, which was put in place
before tzinfo allowed sub-minute time zone offsets.
GH-14878
Use a tighter scope temporary variable to help register allocation.
1% speedup for large string.
Use PyDict_SetItemDefault() for memoizing keys.
At most 4% speedup when the cache hit ratio is low.
There was a discrepancy between the Python and C implementations.
Add singletons ALWAYS_EQ, LARGEST and SMALLEST in test.support
to test mixed type comparison.
Support for RFCOMM, L2CAP, HCI, SCO is based on the BTPROTO_* macros
being defined. Winsock only supports RFCOMM, even though it has a
BTHPROTO_L2CAP macro. L2CAP support would build on windows, but not
necessarily work.
This also adds some basic unittests for constants (all of which existed
prior to this commit, just not on windows) and creating sockets.
pair: Nate Duarte <slacknate@gmail.com>
gc used several PySys_WriteStderr() calls to write stats.
It caused stats mixed up when stderr is shared by multiple
processes like this:
gc: collecting generation 2...
gc: objects in each generation: 0 0gc: collecting generation 2...
gc: objects in each generation: 0 0 126077 126077
gc: objects in permanent generation: 0
gc: objects in permanent generation: 0
gc: done, 112575 unreachable, 0 uncollectablegc: done, 112575 unreachable, 0 uncollectable, 0.2223s elapsed
, 0.2344s elapsed
Expose the CAN_BCM SocketCAN constants used in the bcm_msg_head struct
flags (provided by <linux/can/bcm.h>) under the socket library.
This adds the following constants with a CAN_BCM prefix:
* SETTIMER
* STARTTIMER
* TX_COUNTEVT
* TX_ANNOUNCE
* TX_CP_CAN_ID
* RX_FILTER_ID
* RX_CHECK_DLC
* RX_NO_AUTOTIMER
* RX_ANNOUNCE_RESUME
* TX_RESET_MULTI_IDX
* RX_RTR_FRAME
* CAN_FD_FRAME
The CAN_FD_FRAME flag was introduced in the 4.8 kernel, while the other
ones were present since SocketCAN drivers were mainlined in 2.6.25. As
such, it is probably unnecessary to guard against these constants being
missing.
When scanning the string, most characters are valid, so
checking for invalid characters first means never needing
to check the value of strict on valid strings, and only
needing to check it on invalid characters when doing
non-strict parsing of invalid strings.
This provides a measurable reduction in per-character
processing time (~11% in the pre-merge patch testing).
Deprecate the parser module and add a deprecation warning triggered on import and a warning block in the documentation.
https://bugs.python.org/issue37268
Automerge-Triggered-By: @pablogsal