- Don't turn a non-tuple argument into a one-tuple. Rather, the
caller must pass a format that causes Py_VaBuildValue() to return a
tuple.
- Speed things up by calling PyObject_Call (which is fairly low-level
and straightforward) rather than PyObject_CallObject (which calls
PyEval_CallObjectWithKeywords which calls PyObject_Call, and nothing
is really done in the mean time except some tests for NULL args and
valid types, which are already guaranteed).
- Cosmetics.
Other places:
- Make sure that the format argument to call_method() is surrounded by
parentheses, so it will cause a tuple to be created.
- Replace a few calls to PyEval_CallObject() with a surefire tuple for
args to calls to PyObject_Call(). (A few calls to
PyEval_CallObject() remain that have NULL for args.)
directly, as the only thing done here (replace NULL args with an empty
tuple) is also done there.
XXX Maybe we should take one step further and equate the two at the
macro level? That's harder though because PyEval_Call* is declared in
a header that's not included standard. But it is silly that
PyObject_CallObject calls PyEval_CallObject which calls back to
PyObject_Call. Maybe PyEval_CallObject should be moved into this file
instead? All I know is that there are too many call APIs! The
differences between PyObject_Call and PyEval_CallObjectWithKeywords is
that the latter allows args to be NULL, and does explicit type checks
for args and kwds.
A surprising number of changes to split tp_new into tp_new and tp_init.
Turned out the older PyFile_FromFile() didn't initialize the memory it
allocated in all (error) cases, which caused new sanity asserts
elsewhere to fail left & right (and could have, e.g., caused file_dealloc
to try decrefing random addresses).
keys are true strings -- no subclasses need apply. This may be debatable.
The problem is that a str subclass may very well want to override __eq__
and/or __hash__ (see the new example of case-insensitive strings in
test_descr), but go-fast shortcuts for strings are ubiquitous in our dicts
(and subclass overrides aren't even looked for then). Another go-fast
reason for the change is that PyCheck_StringExact() is a quicker test
than PyCheck_String(), and we make such a test on virtually every access
to every dict.
OTOH, a str subclass may also be perfectly happy using the base str eq
and hash, and this change slows them a lot. But those cases are still
hypothetical, while Python's own reliance on true-string dicts is not.
just by doing type(f) where f is any file object. This left a hole in
restricted execution mode that rexec.py can't plug by itself (although it
can plug part of it; the rest is plugged in fileobject.c now).
on to the tp_new slot (if non-NULL), as well as to the tp_init slot (if
any). A sane type implementing both tp_new and tp_init should probably
pay attention to the arguments in only one of them.
with the same value instead. This ensures that a string (or string
subclass) object's ob_sinterned pointer is always a str (or NULL), and
that the dict of interned strings only has strs as keys.
+ These were leaving the hash fields at 0, which all string and unicode
routines believe is a legitimate hash code. As a result, hash() applied
to str and unicode subclass instances always returned 0, which in turn
confused dict operations, etc.
+ Changed local names "new"; no point to antagonizing C++ compilers.
subclasses, all "the usual" ones (slicing etc), plus replace, translate,
ljust, rjust, center and strip. I don't know how to be sure they've all
been caught.
Question: Should we complain if someone tries to intern an instance of
a string subclass? I hate to slow any code on those paths.
tuple(i) repaired to return a true tuple when i is an instance of a
tuple subclass.
Added PyTuple_CheckExact macro.
PySequence_Tuple(): if a tuple-like object isn't exactly a tuple, it's
not safe to return the object as-is -- make a new tuple of it instead.
Given an immutable type M, and an instance I of a subclass of M, the
constructor call M(I) was just returning I as-is; but it should return a
new instance of M. This fixes it for M in {int, long}. Strings, floats
and tuples remain to be done.
Added new macros PyInt_CheckExact and PyLong_CheckExact, to more easily
distinguish between "is" and "is a" (i.e., only an int passes
PyInt_CheckExact, while any sublass of int passes PyInt_Check).
Added private API function _PyLong_Copy.
Subtlety on Windows: if we change test_largefile.py to use a file
> 4GB, it still fails. A debug session suggests this is because
fseek(fp, 0, 2) refuses to seek to the end of the file when the file
is > 4GB, because it uses the SetFilePointer() in 32-bit mode.
But it only fails when we seek relative to the end of the file,
because in the other seek modes only calls to fgetpos() and fsetpos()
are made, which use Get/SetFilePointer() in 64-bit mode. Solution:
#ifdef MS_WInDOWS, replace the call to fseek(fp, ...) with a call to
_lseeki64(fileno(fp), ...). Make sure to call fflush(fp) first.
(XXX Could also replace the entire branch with a call to _lseeki64().
Would that be more efficient? Certainly less generated code.)
(XXX This needs more testing. I can't actually test that it works for
files >4GB on my Win98 machine, because the filesystem here won't let
me create files >=4GB at all. Tim should test this on his Win2K
machine.)
- use PyModule_Check() instead of PyObject_TypeCheck(), now we can.
- don't assert that the __dict__ gotten out of a module is always
a dictionary; check its type, and raise an exception if it's not.
iterable object. I'm not sure how that got overlooked before!
Got rid of the internal _PySequence_IterContains, introduced a new
internal _PySequence_IterSearch, and rewrote all the iteration-based
"count of", "index of", and "is the object in it or not?" routines to
just call the new function. I suppose it's slower this way, but the
code duplication was getting depressing.
the base classes is not a classic class, and its class (the metaclass)
is callable, call the metaclass to do the deed.
One effect of this is that, when mixing classic and new-style classes
amongst the bases of a class, it doesn't matter whether the first base
class is a classic class or not: you will always get the error
"TypeError: metatype conflict among bases". (Formerly, with a classic
class first, you'd get "TypeError: PyClass_New: base must be a class".)
Another effect is that multiple inheritance from ExtensionClass.Base,
with a classic class as the first class, transfers control to the
ExtensionClass.Base class. This is what we need for SF #443239 (and
also for running Zope under 2.2a4, before ExtensionClass is replaced).
corresponding "getitem" operation (sq_item or mp_subscript) is
implemented. I realize that "sequence-ness" and "mapping-ness" are
poorly defined (and the tests may still be wrong for user-defined
instances, which always have both slots filled), but I believe that a
sequence that doesn't support its getitem operation should not be
considered a sequence. All other operations are optional though.
For example, the ZODB BTree tests crashed because PySequence_Check()
returned true for a dictionary! (In 2.2, the dictionary type has a
tp_as_sequence pointer, but the only field filled is sq_contains, so
you can write "if key in dict".) With this fix, all standalone ZODB
tests succeed.
a->tp_mro. If a doesn't have class, it's considered a subclass only
of itself or of 'object'.
This one fix is enough to prevent the ExtensionClass test suite from
dumping core, but that doesn't say much (it's a rather small test
suite). Also note that for ExtensionClass-defined types, a different
subclass test may be needed. But I haven't checked whether
PyType_IsSubtype() is actually used in situations where this matters
-- probably it doesn't, since we also don't check for classic classes.
Curious: the MS docs say stati64 etc are supported even on Win95, but
Win95 doesn't support a filesystem that allows partitions > 2 Gb.
test_largefile: This was opening its test file in text mode. I have no
idea how that worked under Win64, but it sure needs binary mode on Win98.
BTW, on Win98 test_largefile runs quickly (under a second).
While not even documented, they were clearly part of the C API,
there's no great difficulty to support them, and it has the cool
effect of not requiring any changes to ExtensionClass.c.
requires that errno ever get set, and it looks like glibc is already
playing that game. New rules:
+ Never use HUGE_VAL. Use the new Py_HUGE_VAL instead.
+ Never believe errno. If overflow is the only thing you're interested in,
use the new Py_OVERFLOWED(x) macro. If you're interested in any libm
errors, use the new Py_SET_ERANGE_IF_OVERFLOW(x) macro, which attempts
to set errno the way C89 said it worked.
Unfortunately, none of these are reliable, but they work on Windows and I
*expect* under glibc too.
I believe this works on Linux (tested both on a system with large file
support and one without it), and it may work on Solaris 2.7.
The changes are twofold:
(1) The configure script now boldly tries to set the two symbols that
are recommended (for Solaris and Linux), and then tries a test
script that does some simple seeking without writing.
(2) The _portable_{fseek,ftell} functions are a little more systematic
in how they try the different large file support options: first
try fseeko/ftello, but only if off_t is large; then try
fseek64/ftell64; then try hacking with fgetpos/fsetpos.
I'm keeping my fingers crossed. The meaning of the
HAVE_LARGEFILE_SUPPORT macro is not at all clear.
I'll see if I can get it to work on Windows as well.
the fiddling is simply due to that no caller of PyLong_AsDouble ever
checked for failure (so that's fixing old bugs). PyLong_AsDouble is much
faster for big inputs now too, but that's more of a happy consequence
than a design goal.
Guido van Rossum
Tim Peters
Skip Montanaro
Martin v. Löwis