Rather than trying to second-guess the various error returns
of a second connect(), use select() to determine whether the
socket becomes writable (which means connected).
inet_aton() rather than inet_addr() -- the latter is obsolete because
it has a problem: "255.255.255.255" is a valid address but
indistinguishable from an error.
(I'm not sure if inet_aton() exists everywhere -- in case it doesn't,
I've left the old code in with an #ifdef.)
The attached patch enables shared extension
modules to build cleanly under Cygwin without
moving the static initialization of certain function
pointers (i.e., ones exported from the Python
DLL core) to a module initialization function.
Additionally, this patch fixes the modules that
have been changed in the past to accommodate
Cygwin.
On HPUX, Solaris, Tru64 (Dec UNIX), and IRIX (I think),
O_NONBLOCK is the POSIX version of non-blocking I/O
which is what we want.
On Linux and FreeBSD (at least), O_NONBLOCK and O_NDELAY are the same.
So this change should have no negative effect on those platforms.
Tested on Linux, Solaris, HPUX.
Thanks to Anders Qvist for diagnosing this problem.
value; others were inconsistent in what to name the argument or return
value; a few module-global functions had "socket." in front of their
name, against convention.
WSAEWOULDBLOCK, the second connect() attempt appears to yield WSAEISCONN
on Win98 but WSAEINVAL on Win2K. So accept either as meaning "yawn,
fine". This allows test_socket to succeed on my Win2K box (which it
already did on my Win98SE box).
The staticforward define was needed to support certain broken C
compilers (notably SCO ODT 3.0, perhaps early AIX as well) botched the
static keyword when it was used with a forward declaration of a static
initialized structure. Standard C allows the forward declaration with
static, and we've decided to stop catering to broken C compilers. (In
fact, we expect that the compilers are all fixed eight years later.)
I'm leaving staticforward and statichere defined in object.h as
static. This is only for backwards compatibility with C extensions
that might still use it.
XXX I haven't updated the documentation.
that retries the connect() call in timeout mode so it can be shared
between connect() and connect_ex(), and needs only a single #ifdef.
The test for this was doing funky stuff I don't approve of,
so I removed it in favor of a simpler test. This allowed me
to implement a simpler, "purer" form of the timeout retry code.
Hopefully that's enough (if you want to be fancy, use non-blocking
mode and decode the errors yourself, like before).
- setblocking(0) and settimeout(0) are now equivalent, and ditto for
setblocking(1) and settimeout(None).
- Don't raise an exception from internal_select(); let the final call
report the error (this means you will get an EAGAIN error instead of
an ETIMEDOUT error -- I don't care).
- Move the select to inside the Py_{BEGIN,END}_ALLOW_THREADS brackets,
so other theads can run (this was a bug in the original code).
- Redid the retry logic in connect() and connect_ex() to avoid masking
errors. This probably doesn't work for Windows yet; I'll fix that
next. It may also fail on other platforms, depending on what
retrying a connect does; I need help with this.
- Get rid of the retry logic in accept(). I don't think it was needed
at all. But I may be wrong.
settimeout(). Already, settimeout() canceled non-blocking mode; now,
setblocking() also cancels the timeout. This is easier to document.
(XXX should settimeout(0) be an alias for setblocking(0)? They seem
to have roughly the same effect. Also, I'm not sure that the code in
connect() and accept() is correct in all cases. We'll sort this out
soon enough.)
not testing it -- apparently test_timeout.py doesn't test anything
useful):
In internal_select():
- The tv_usec part of the timeout for select() was calculated wrong.
- The first argument to select() was one too low.
- The sense of the direction argument to internal_select() was
inverted.
In PySocketSock_settimeout():
- The calls to internal_setblocking() were swapped.
Also, repaired some comments and fixed the test for the return value
of internal_select() in sendall -- this was in the original patch.
I've made considerable changes to Michael's code, specifically to use
the select() system call directly and to store the timeout as a C
double instead of a Python object; internally, -1.0 (or anything
negative) represents the None from the API.
I'm not 100% sure that all corner cases are covered correctly, so
please keep an eye on this. Next I'm going to try it Windows before
Tim complains.
No way is this a bugfix candidate. :-)
don't understand how this function works, also beefed up the docs. The
most common usage error is of this form (often spread out across gotos):
if (_PyString_Resize(&s, n) < 0) {
Py_DECREF(s);
s = NULL;
goto outtahere;
}
The error is that if _PyString_Resize runs out of memory, it automatically
decrefs the input string object s (which also deallocates it, since its
refcount must be 1 upon entry), and sets s to NULL. So if the "if"
branch ever triggers, it's an error to call Py_DECREF(s): s is already
NULL! A correct way to write the above is the simpler (and intended)
if (_PyString_Resize(&s, n) < 0)
goto outtahere;
Bugfix candidate.
Martin v. Löwis
Guido van Rossum
Tim Peters
Neal Norwitz
Jason Tishler
Andrew MacIntyre
Mark Hammond
Jeremy Hylton
Jack Jansen
Neil Schemenauer
Fred Drake