In C++, it's an error to pass a string literal to a char* function
without a const_cast(). Rather than require every C++ extension
module to put a cast around string literals, fix the API to state the
const-ness.
I focused on parts of the API where people usually pass literals:
PyArg_ParseTuple() and friends, Py_BuildValue(), PyMethodDef, the type
slots, etc. Predictably, there were a large set of functions that
needed to be fixed as a result of these changes. The most pervasive
change was to make the keyword args list passed to
PyArg_ParseTupleAndKewords() to be a const char *kwlist[].
One cast was required as a result of the changes: A type object
mallocs the memory for its tp_doc slot and later frees it.
PyTypeObject says that tp_doc is const char *; but if the type was
created by type_new(), we know it is safe to cast to char *.
[ 991812 ] PyArg_ParseTuple can miss errors with warnings as exceptions
as suggested in the report.
This is definitely a 2.3 candidate (as are most of the checkins I've
made in the last month...)
New functions:
unsigned long PyInt_AsUnsignedLongMask(PyObject *);
unsigned PY_LONG_LONG) PyInt_AsUnsignedLongLongMask(PyObject *);
unsigned long PyLong_AsUnsignedLongMask(PyObject *);
unsigned PY_LONG_LONG) PyLong_AsUnsignedLongLongMask(PyObject *);
New and changed format codes:
b unsigned char 0..UCHAR_MAX
B unsigned char none **
h unsigned short 0..USHRT_MAX
H unsigned short none **
i int INT_MIN..INT_MAX
I * unsigned int 0..UINT_MAX
l long LONG_MIN..LONG_MAX
k * unsigned long none
L long long LLONG_MIN..LLONG_MAX
K * unsigned long long none
Notes:
* New format codes.
** Changed from previous "range-and-a-half" to "none"; the
range-and-a-half checking wasn't particularly useful.
New test test_getargs2.py, to verify all this.
use wrappers on all platforms, to make this as consistent as possible x-
platform (in particular, make sure there's at least one \0 byte in
the output buffer). Also document more of the truth about what these do.
getargs.c, seterror(): Three computations of remaining buffer size were
backwards, thus telling PyOS_snprintf the buffer is larger than it
actually is. This matters a lot now that PyOS_snprintf ensures there's a
trailing \0 byte (because it didn't get the truth about the buffer size,
it was storing \0 beyond the true end of the buffer).
sysmodule.c, mywrite(): Simplify, now that PyOS_vsnprintf guarantees to
produce a \0 byte.
vgetargskeywords(): Now that this routine is checking for bad input
(rather than dump core in some cases), some bad calls are raising errors
that previously "worked". This patch makes the error strings more
revealing, and changes the exceptions from SystemError to RuntimeError
(under the theory that SystemError is more of a "can't happen!" assert-
like thing, and so inappropriate for bad arguments to a public C API
function).
seterror() uses a char array and a pointer to the current position in
that array. Use snprintf() and compute the amount of space left in
the buffer based on the current pointer position.
+ Squash another potential buffer overrun.
+ Simplify the keyword-arg loop by decrementing the count of keywords
remaining instead of incrementing Yet Another Variable; also break
out early if the number of keyword args remaining hits 0.
Since I hit the function's closing curly brace with this patch, that's
enough of this for now <wink>.
The "need" for this was probably removed by an earlier patch that stopped
the loop right before it from passing NULL to a dict lookup routine.
I still haven't convinced myself that the next loop is correct, so am
leaving the next mysterious PyErr_Clear() call in for now.
+ Generally test nkeywords against 0 instead of keywords against NULL
(saves a little work if an empty keywords dict is passed, and is
conceptually more on-target regardless).
+ When a call erroneously specifies a keyword argument both by position
and by keyword name:
- It was easy to provoke this routine into an internal buffer overrun
by using a long argument name. Now uses PyErr_format instead (which
computes a safe buffer size).
- Improved the error msg.
+ Got rid of now-redundant dict typecheck.
+ Renamed nkwds to nkwlist. Now all the "counting" vrbls have names
related to the things they're counting in an obvious way.
+ Renamed argslen to nargs.
+ Renamed kwlen to nkeywords. This one was especially confusing because
kwlen wasn't the length of the kwlist argument, but of the keywords
argument.
+ Removed now-redundant tuple typecheck.
+ Renamed "tplen" local to "argslen" (it's the length of the "args"
argument; I suppose "tp" was for "Tim Peters should rename me
someday <wink>).
introduced this bug just a little while ago, when *adding* internal error
checks).
vgetargskeywords: Rewrote the section that crawls over the format string.
+ Added block comment so it won't take the next person 15 minutes to
reverse-engineer what it's doing.
+ Lined up the "else" clauses.
+ Rearranged the ifs in decreasing order of likelihood (for speed).
and raise an error if they're insane.
vgetargskeywords: the same, except that since this is an internal routine,
just assert that the arguments are sane.
the kwlist vector whenever there was a mix of positional and keyword
arguments, and the number of positional arguments exceeded the length
of the kwlist vector. If there was just one more positional arg than
keyword, the kwlist-terminating NULL got passed to PyMapping_HasKeyString,
which set an internal error that vgetargskeywords() then squashed (but
it's impossible to say whether it knew it was masking an error). If
more than one more positional argument, it went on to pass random trash
to PyMapping_HasKeyString, which is why the example at the start
happened to kill the process.
Pure bugfix candidate.
Reported by Fredrik Lundh on python-dev.
The conversimple() code that handles Unicode arguments and converts
them to the default encoding now calls converterr() with the original
Unicode argument instead of the NULL returned by the failed encoding
attempt.
- Do not compile unicodeobject, unicodectype, and unicodedata if Unicode is disabled
- check for Py_USING_UNICODE in all places that use Unicode functions
- disables unicode literals, and the builtin functions
- add the types.StringTypes list
- remove Unicode literals from most tests.
And remove all the extern decls in the middle of .c files.
Apparently, it was excluded from the header file because it is
intended for internal use by the interpreter. It's still intended for
internal use and documented as such in the header file.
In the default branch, keep three ifs that are used if level == 0, the
most common case. Note that first if here is a slight optimization
for the 'O' format.
Second part of SF patch 426072.
Note that lots of code was re-indented.
Replace two-step of convertsimple() and convertsimple1() with
convertsimple() and helper converterr(), which is called to format
error messages when convertsimple() fails. The old code did all the
real work in convertsimple1(), but deferred error message formatting
to conversimple(). The result was paying the price of a second
function call on every call just to format error messages in the
failure cases.
Factor out of the buffer-handling code in convertsimple() and package
it as convertbuffer().
Add two macros to ease readability of Unicode coversions,
UNICODE_DEFAULT_ENCODING() and CONV_UNICODE, an error string.
The convertsimple() routine had awful indentation problems, primarily
because there were two tabs between the case line and the body of the
case statements. This patch reformats the entire function to have a
single tab between case line and case body, which makes the code
easier to read (and consistent with ceval). The introduction of
converterr() exacerbated the problem and prompted this fix.
Also, eliminate non-standard whitespace after opening paren and before
closing paren in a few if statements.
(This checkin is part of SF patch 426072.)
_testcapimodule.c
make sure PyList_Reverse doesn't blow up again
getargs.c
assert args isn't NULL at the top of vgetargs1 instead of
waiting for a NULL-pointer dereference at the end
message, and tries to make the messages more consistent and helpful when
the wrong number of arguments or duplicate keyword arguments are supplied.
Comes with more tests for test_extcall.py and and an update to an error
message in test/output/test_pyexpat.
Add definitions of INT_MAX and LONG_MAX to pyport.h.
Remove includes of limits.h and conditional definitions of INT_MAX
and LONG_MAX elsewhere.
This closes SourceForge patch #101659 and bug #115323.
"s#" will now return a pointer to the default encoded string data
of the Unicode object instead of a pointer to the raw UTF-16
data.
The latter is still available via PyObject_AsReadBuffer().
The patch also adds an optimization for string objects which is
based on the fact that string objects return the raw character data
for getreadbuffer access and are always single-segment.
-32768..65535 is acceptable. Added B specifier (with values from
-128..255). No L added (which would have completed the set) because l
already accepts any value (and the letter L is taken for quadwords).
the Python Unicode implementation.
The internal buffer used for implementing the buffer protocol
is renamed to defenc to make this change visible. It now holds the
default encoded version of the Unicode object and is calculated
on demand (NULL otherwise).
Since the default encoding defaults to ASCII, this will mean that
Unicode objects which hold non-ASCII characters will no longer
work on C APIs using the "s" or "t" parser markers. C APIs must now
explicitly provide Unicode support via the "u", "U" or "es"/"es#"
parser markers in order to work with non-ASCII Unicode strings.
(Note: this patch will also have to be applied to the 1.6 branch
of the CVS tree.)
comments, docstrings or error messages. I fixed two minor things in
test_winreg.py ("didn't" -> "Didn't" and "Didnt" -> "Didn't").
There is a minor style issue involved: Guido seems to have preferred English
grammar (behaviour, honour) in a couple places. This patch changes that to
American, which is the more prominent style in the source. I prefer English
myself, so if English is preferred, I'd be happy to supply a patch myself ;)
This patch fixes a problem on AIX with the signed int case code in
getargs.c, after Trent Mick's intervention about MIN/MAX overflow
checks. The AIX compiler/optimizer generates bogus code with the
default flags "-g -O" causing test_builtin to fail: int("10", 16) <>
16L. Swapping the two checks in the signed int code makes the problem
go away.
Also, make the error messages fit in 80 char lines in the
source.
Limit the 'b' formatter of PyArg_ParseTuple to valid values of an unsigned
char, i.e. [0,UCHAR_MAX]. It is expected that this is the common usage of 'b'.
An OverflowError is raised if the parsed value is outside this range.
Changes the 'b', 'h', and 'i' formatters in PyArg_ParseTuple to raise an
Overflow exception if they overflow (previously they just silently
overflowed).
Changes by Guido: always accept values [0..255] (in addition to
[CHAR_MIN..CHAR_MAX]) for 'b' format; changed some spaces into tabs in
other code.
Added 'u' and 'u#' tags for PyArg_ParseTuple - these turn a
PyUnicodeObject argument into a Py_UNICODE * buffer, or a Py_UNICODE *
buffer plus a length with the '#'. Also added an analog to 'U'
for Py_BuildValue.
Fixed a memory leak found by Fredrik Lundh. Instead of
PyUnicode_AsUTF8String() we now use _PyUnicode_AsUTF8String() which
returns the string object without incremented refcount (and assures
that the so obtained object remains alive until the Unicode object is
garbage collected).
The attached patch set includes a workaround to get Python with
Unicode compile on BSDI 4.x (courtesy Thomas Wouters; the cause
is a bug in the BSDI wchar.h header file) and Python interfaces
for the MBCS codec donated by Mark Hammond.
Also included are some minor corrections w/r to the docs of
the new "es" and "es#" parser markers (use PyMem_Free() instead
of free(); thanks to Mark Hammond for finding these).
The unicodedata tests are now in a separate file
(test_unicodedata.py) to avoid problems if the module cannot
be found.
Attached you find the latest update of the Unicode implementation.
The patch is against the current CVS version.
It includes the fix I posted yesterday for the core dump problem
in codecs.c (was introduced by my previous patch set -- sorry),
adds more tests for the codecs and two new parser markers
"es" and "es#".
The MS compiler doesn't call it 'long long', it uses __int64,
so a new #define, LONG_LONG, has been added and all occurrences
of 'long long' are replaced with it.
Date: Thu, 14 Sep 1995 12:18:20 -0400
From: Alan Morse <alan@dvcorp.com>
To: python-list@cwi.nl
Subject: getargs bug in 1.2 and 1.3 BETA
We have found a bug in the part of the getargs code that we added
and submitted, and which was incorporated into 1.1.
The parsing of "O?" format specifiers is not handled correctly;
there is no "else" for the "if" and therefore it can never fail.
What's worse, the advancing of the varargs pointer is not
handled properly, so from then on it is out of sync, wreaking
all sorts of havoc. (If it had failed properly, then the out-of-sync
varargs would not have been an issue.)
Below is the context diff for the change.
Note that I have made a few stylistic changes beyond adding the
else case, namely:
1) Making the "O" case follow the convention established by the other
format specifiers of getting all their vararg arguments before
performing the test, rather than getting some before and some after
the test passes.
2) Making the logic of the tests parallel, so the "if" part indicates
that the format is accepted and the "else" part indicates that the
format has failed. They were inconsistent with each other and with the
the other format specifiers.
-Alan Morse (amorse@dvcorp.com)
Neal Norwitz
Martin v. Löwis
Georg Brandl
Jeremy Hylton
Michael W. Hudson
Brett Cannon
Guido van Rossum
Thomas Heller
Neil Schemenauer
Walter Dörwald
Marc-André Lemburg
Tim Peters
Fred Drake
Mark Hammond
Ka-Ping Yee
Barry Warsaw
Jack Jansen
Thomas Wouters