Unix Plink, Unix Pageant in server mode, Uppity, and the post-
connection form of PSFTP's command-line reading code all had very
similar loops in them, which run a pollwrapper and mediate between
that, timers, and toplevel callbacks. It's long past time the common
code between all of those became a reusable shared routine.
So, this commit introduces uxcliloop.c, and turns all the previous
copies of basically the same loop into a call to cli_main_loop with
various callback functions to configure the parts that differ.
The global 'int flags' has always been an ugly feature of this code
base, and I suddenly thought that perhaps it's time to start throwing
it out, one flag at a time, until it's totally unused.
My first target is FLAG_VERBOSE. This was usually set by cmdline.c
when it saw a -v option on the program's command line, except that GUI
PuTTY itself sets it unconditionally on startup. And then various bits
of the code would check it in order to decide whether to print a given
message.
In the current system of front-end abstraction traits, there's no
_one_ place that I can move it to. But there are two: every place that
checked FLAG_VERBOSE has access to either a Seat or a LogPolicy. So
now each of those traits has a query method for 'do I want verbose
messages?'.
A good effect of this is that subsidiary Seats, like the ones used in
Uppity for the main SSH server module itself and the server end of
shell channels, now get to have their own verbosity setting instead of
inheriting the one global one. In fact I don't expect any code using
those Seats to be generating any messages at all, but if that changes
later, we'll have a way to control it. (Who knows, perhaps logging in
Uppity might become a thing.)
As part of this cleanup, I've added a new flag to cmdline_tooltype,
called TOOLTYPE_NO_VERBOSE_OPTION. The unconditionally-verbose tools
now set that, and it has the effect of making cmdline.c disallow -v
completely. So where 'putty -v' would previously have been silently
ignored ("I was already verbose"), it's now an error, reminding you
that that option doesn't actually do anything.
Finally, the 'default_logpolicy' provided by uxcons.c and wincons.c
(with identical definitions) has had to move into a new file of its
own, because now it has to ask cmdline.c for the verbosity setting as
well as asking console.c for the rest of its methods. So there's a new
file clicons.c which can only be included by programs that link
against both cmdline.c _and_ one of the *cons.c, and I've renamed the
logpolicy to reflect that.
Up until now, it's been a variadic _function_, whose argument list
consists of 'const char *' ASCIZ strings to concatenate, terminated by
one containing a null pointer. Now, that function is dupcat_fn(), and
it's wrapped by a C99 variadic _macro_ called dupcat(), which
automatically suffixes the null-pointer terminating argument.
This has three benefits. Firstly, it's just less effort at every call
site. Secondly, it protects against the risk of accidentally leaving
off the NULL, causing arbitrary words of stack memory to be
dereferenced as char pointers. And thirdly, it protects against the
more subtle risk of writing a bare 'NULL' as the terminating argument,
instead of casting it explicitly to a pointer. That last one is
necessary because C permits the macro NULL to expand to an integer
constant such as 0, so NULL by itself may not have pointer type, and
worse, it may not be marshalled in a variadic argument list in the
same way as a pointer. (For example, on a 64-bit machine it might only
occupy 32 bits. And yet, on another 64-bit platform, it might work
just fine, so that you don't notice the mistake!)
I was inspired to do this by happening to notice one of those bare
NULL terminators, and thinking I'd better check if there were any
more. Turned out there were quite a few. Now there are none.
The number of people has been steadily increasing who read our source
code with an editor that thinks tab stops are 4 spaces apart, as
opposed to the traditional tty-derived 8 that the PuTTY code expects.
So I've been wondering for ages about just fixing it, and switching to
a spaces-only policy throughout the code. And I recently found out
about 'git blame -w', which should make this change not too disruptive
for the purposes of source-control archaeology; so perhaps now is the
time.
While I'm at it, I've also taken the opportunity to remove all the
trailing spaces from source lines (on the basis that git dislikes
them, and is the only thing that seems to have a strong opinion one
way or the other).
Apologies to anyone downstream of this code who has complicated patch
sets to rebase past this change. I don't intend it to be needed again.
glob.h is another missing facility in Android+Termux.
The workaround is to condition out local wildcard support completely,
so that PSFTP commands like 'mput *.txt' won't manage to do anything.
But at least the program will compile.
I've always thought poll was more hassle to set up, because if you
want to reuse part of your pollfds list between calls then you have to
index every fd by its position in the list as well as the fd number
itself, which gives you twice as many indices to keep track of than if
the fd is always its own key.
But the problem is that select is fundamentally limited to the range
of fds that can fit in an fd_set, which is not the range of fds that
can _exist_, so I've had a change of heart and now have to go with
poll.
For the moment, I've surrounded it with a 'pollwrapper' structure that
lets me treat it more or less like select, containing a tree234 that
maps each fd to its location in the list, and also translating between
the simple select r/w/x classification and the richer poll flags.
That's let me do the migration with minimal disruption to the call
sites.
In future perhaps I can start using poll more directly, and/or using
the richer flag system (though the latter might be fiddly because of
sometimes being constrained to use the glib event loop). But this will
do for now.
Now if a pathname ends with a slash already, we detect that (using the
shiny new ptrlen_endswith), and don't bother putting another one in.
No functional change, but this should improve the occasional error
message, e.g. 'pscp remote:some.filename /' will now say it can't
create /some.filename instead of //some.filename.
The idea of these is that they centralise the common idiom along the
lines of
if (logical_array_len >= physical_array_size) {
physical_array_size = logical_array_len * 5 / 4 + 256;
array = sresize(array, physical_array_size, ElementType);
}
which happens at a zillion call sites throughout this code base, with
different random choices of the geometric factor and additive
constant, sometimes forgetting them completely, and generally doing a
lot of repeated work.
The new macro sgrowarray(array,size,n) has the semantics: here are the
array pointer and its physical size for you to modify, now please
ensure that the nth element exists, so I can write into it. And
sgrowarrayn(array,size,n,m) is the same except that it ensures that
the array has size at least n+m (so sgrowarray is just the special
case where m=1).
Now that this is a single centralised implementation that will be used
everywhere, I've also gone to more effort in the implementation, with
careful overflow checks that would have been painful to put at all the
previous call sites.
This commit also switches over every use of sresize(), apart from a
few where I really didn't think it would gain anything. A consequence
of that is that a lot of array-size variables have to have their types
changed to size_t, because the macros require that (they address-take
the size to pass to the underlying function).
ssh_sftp_loop_iteration() used to return failure if no file handle was
in use for the select loop, on the basis that that means select would
just loop forever. But if there's a toplevel callback pending - in
particular, if it's going to do something like emptying ssh->in_raw
which will put an fd _back into_ the next iteration of the select loop
- then that's not a good enough reason to return permanent failure.
Just go round the loop, run the callback, and try again.
A user points out that the call to close_directory() in pscp.c's
rsource() function should have been inside rather than outside the if
statement that checks whether the directory handle is NULL. As a
result, any failed attempt to open a directory during a 'pscp -r'
recursive upload leads to a null-pointer dereference.
Moved the close_directory call to where it should be, and also
arranged to print the OS error code if the directory-open fails, by
also changing the API of open_directory to return an error string on
failure.
This fixes a batch of clang-analyzer warnings of the form 'you
declared / assigned this variable and then never use it'. It doesn't
fix _all_ of them - some are there so that when I add code in the
future _it_ can use the variable without me having to remember to
start setting it - but these are the ones I thought it would make the
code better instead of worse to fix.
My normal habit these days, in new code, is to treat int and bool as
_almost_ completely separate types. I'm still willing to use C's
implicit test for zero on an integer (e.g. 'if (!blob.len)' is fine,
no need to spell it out as blob.len != 0), but generally, if a
variable is going to be conceptually a boolean, I like to declare it
bool and assign to it using 'true' or 'false' rather than 0 or 1.
PuTTY is an exception, because it predates the C99 bool, and I've
stuck to its existing coding style even when adding new code to it.
But it's been annoying me more and more, so now that I've decided C99
bool is an acceptable thing to require from our toolchain in the first
place, here's a quite thorough trawl through the source doing
'boolification'. Many variables and function parameters are now typed
as bool rather than int; many assignments of 0 or 1 to those variables
are now spelled 'true' or 'false'.
I managed this thorough conversion with the help of a custom clang
plugin that I wrote to trawl the AST and apply heuristics to point out
where things might want changing. So I've even managed to do a decent
job on parts of the code I haven't looked at in years!
To make the plugin's work easier, I pushed platform front ends
generally in the direction of using standard 'bool' in preference to
platform-specific boolean types like Windows BOOL or GTK's gboolean;
I've left the platform booleans in places they _have_ to be for the
platform APIs to work right, but variables only used by my own code
have been converted wherever I found them.
In a few places there are int values that look very like booleans in
_most_ of the places they're used, but have a rarely-used third value,
or a distinction between different nonzero values that most users
don't care about. In these cases, I've _removed_ uses of 'true' and
'false' for the return values, to emphasise that there's something
more subtle going on than a simple boolean answer:
- the 'multisel' field in dialog.h's list box structure, for which
the GTK front end in particular recognises a difference between 1
and 2 but nearly everything else treats as boolean
- the 'urgent' parameter to plug_receive, where 1 vs 2 tells you
something about the specific location of the urgent pointer, but
most clients only care about 0 vs 'something nonzero'
- the return value of wc_match, where -1 indicates a syntax error in
the wildcard.
- the return values from SSH-1 RSA-key loading functions, which use
-1 for 'wrong passphrase' and 0 for all other failures (so any
caller which already knows it's not loading an _encrypted private_
key can treat them as boolean)
- term->esc_query, and the 'query' parameter in toggle_mode in
terminal.c, which _usually_ hold 0 for ESC[123h or 1 for ESC[?123h,
but can also hold -1 for some other intervening character that we
don't support.
In a few places there's an integer that I haven't turned into a bool
even though it really _can_ only take values 0 or 1 (and, as above,
tried to make the call sites consistent in not calling those values
true and false), on the grounds that I thought it would make it more
confusing to imply that the 0 value was in some sense 'negative' or
bad and the 1 positive or good:
- the return value of plug_accepting uses the POSIXish convention of
0=success and nonzero=error; I think if I made it bool then I'd
also want to reverse its sense, and that's a job for a separate
piece of work.
- the 'screen' parameter to lineptr() in terminal.c, where 0 and 1
represent the default and alternate screens. There's no obvious
reason why one of those should be considered 'true' or 'positive'
or 'success' - they're just indices - so I've left it as int.
ssh_scp_recv had particularly confusing semantics for its previous int
return value: its call sites used '<= 0' to check for error, but it
never actually returned a negative number, just 0 or 1. Now the
function and its call sites agree that it's a bool.
In a couple of places I've renamed variables called 'ret', because I
don't like that name any more - it's unclear whether it means the
return value (in preparation) for the _containing_ function or the
return value received from a subroutine call, and occasionally I've
accidentally used the same variable for both and introduced a bug. So
where one of those got in my way, I've renamed it to 'toret' or 'retd'
(the latter short for 'returned') in line with my usual modern
practice, but I haven't done a thorough job of finding all of them.
Finally, one amusing side effect of doing this is that I've had to
separate quite a few chained assignments. It used to be perfectly fine
to write 'a = b = c = TRUE' when a,b,c were int and TRUE was just a
the 'true' defined by stdbool.h, that idiom provokes a warning from
gcc: 'suggest parentheses around assignment used as truth value'!
I think this is the full set of things that ought logically to be
boolean.
One annoyance is that quite a few radio-button controls in config.c
address Conf fields that are now bool rather than int, which means
that the shared handler function can't just access them all with
conf_{get,set}_int. Rather than back out the rigorous separation of
int and bool in conf.c itself, I've just added a similar alternative
handler function for the bool-typed ones.
This commit includes <stdbool.h> from defs.h and deletes my
traditional definitions of TRUE and FALSE, but other than that, it's a
100% mechanical search-and-replace transforming all uses of TRUE and
FALSE into the C99-standardised lowercase spellings.
No actual types are changed in this commit; that will come next. This
is just getting the noise out of the way, so that subsequent commits
can have a higher proportion of signal.
The annoying int64.h is completely retired, since C99 guarantees a
64-bit integer type that you can actually treat like an ordinary
integer. Also, I've replaced the local typedefs uint32 and word32
(scattered through different parts of the crypto code) with the
standard uint32_t.
This is a new vtable-based abstraction which is passed to a backend in
place of Frontend, and it implements only the subset of the Frontend
functions needed by a backend. (Many other Frontend functions still
exist, notably the wide range of things called by terminal.c providing
platform-independent operations on the GUI terminal window.)
The purpose of making it a vtable is that this opens up the
possibility of creating a backend as an internal implementation detail
of some other activity, by providing just that one backend with a
custom Seat that implements the methods differently.
For example, this refactoring should make it feasible to directly
implement an SSH proxy type, aka the 'jump host' feature supported by
OpenSSH, aka 'open a secondary SSH session in MAINCHAN_DIRECT_TCP
mode, and then expose the main channel of that as the Socket for the
primary connection'. (Which of course you can already do by spawning
'plink -nc' as a separate proxy process, but this would permit it in
the _same_ process without anything getting confused.)
I've centralised a full set of stub methods in misc.c for the new
abstraction, which allows me to get rid of several annoying stubs in
the previous code. Also, while I'm here, I've moved a lot of
duplicated modalfatalbox() type functions from application main
program files into wincons.c / uxcons.c, which I think saves
duplication overall. (A minor visible effect is that the prefixes on
those console-based fatal error messages will now be more consistent
between applications.)
This is another major source of unexplained 'void *' parameters
throughout the code.
In particular, the currently unused testback.c actually gave the wrong
pointer type to its internal store of the frontend handle - it cast
the input void * to a Terminal *, from which it got implicitly cast
back again when calling from_backend, and nobody noticed. Now it uses
the right type internally as well as externally.
This seems to be a knock-on effect of my recent reworking of the SSH
code to be based around queues and callbacks. The loop iteration
function in uxsftp.c (ssh_sftp_do_select) would keep going round its
select loop until something had happened on one of its file
descriptors, and then return to the caller in the assumption that the
resulting data might have triggered whatever condition the caller was
waiting for - and if not, then the caller checks, finds nothing
interesting has happened, and resumes looping with no harm done.
But now, when something happens on an fd, it doesn't _synchronously_
trigger the follow-up condition PSFTP was waiting for (which, at
startup time, happens to be back->sendok() starting to return TRUE).
Instead, it schedules a callback, which will schedule a callback,
which ... ends up setting that flag. But by that time, the loop
function has already returned, the caller has found nothing
interesting and resumed looping, and _now_ the interesting thing
happens but it's too late because ssh_sftp_do_select will wait until
the next file descriptor activity before it next returns.
Solution: give run_toplevel_callbacks a return value which says
whether it's actually done something, and if so, return immediately in
case that was the droid the caller was looking for. As it were.
NFC for the moment, because the bufchain is always specially
constructed to hold exactly the same data that would have been passed
in to the function as a (pointer,length) pair. But this API change
allows get_userpass_input to express the idea that it consumed some
but not all of the data in the bufchain, which means that later on
I'll be able to point the same function at a longer-lived bufchain
containing the full stream of keyboard input and avoid dropping
keystrokes that arrive too quickly after the end of an interactive
password prompt.
NFC: this is a preliminary refactoring, intended to make my life
easier when I start changing around the APIs used to pass user
keyboard input around. The fewer functions even _have_ such an API,
the less I'll have to do at that point.
Unix PSCP, PSFTP, Plink and PuTTYgen now just report their build
platform as '64-bit Unix' or '32-bit Unix', without mentioning
irrelevant details of what flavour of GTK the other tools in the suite
might have been built against.
(In particular, they now won't imply anything outright untrue if there
was no GTK present at build time at all!)
Partly to reassure the user that they got what they asked for, and
partly so that's a clue for us in the logs when we get bug reports.
This involved repurposing platform_psftp_post_option_setup() (no longer
used since e22120fe) as platform_psftp_pre_conn_setup(), and moving it
to after logging is set up.
I noticed today that Unix Plink responds to SIGWINCH by accidentally
dying of EINTR having interrupted its main select loop, and when I
checked, there turn out to be a couple of other select loops with the
same bug.
Protecting our processes from outside interference need not be limited
to just PuTTY: there's no reason why the other SSH-speaking tools
shouldn't have the same treatment (PSFTP, PSCP, Plink), and PuTTYgen
and Pageant which handle private key material.
I noticed that Unix PSCP was unwantedly renaming downloaded files
which had a backslash in their names, because pscp.c's stripslashes()
treated \ as a path component separator, since it hadn't been modified
since PSCP ran on Windows only.
It also turns out that pscp.c, psftp.c and winsftp.c all had a
stripslashes(), and they didn't all have quite the same prototype. So
now there's one in winsftp.c and one in uxsftp.c, with appropriate
OS-dependent behaviour, and the ones in pscp.c and psftp.c are gone.
In case a front end needs to store more than an integer id to be
returned to uxsel_input_remove, we now return a pointer to a
frontend-defined structure.
Having found a lot of unfixed constness issues in recent development,
I thought perhaps it was time to get proactive, so I compiled the
whole codebase with -Wwrite-strings. That turned up a huge load of
const problems, which I've fixed in this commit: the Unix build now
goes cleanly through with -Wwrite-strings, and the Windows build is as
close as I could get it (there are some lingering issues due to
occasional Windows API functions like AcquireCredentialsHandle not
having the right constness).
Notable fallout beyond the purely mechanical changing of types:
- the stuff saved by cmdline_save_param() is now explicitly
dupstr()ed, and freed in cmdline_run_saved.
- I couldn't make both string arguments to cmdline_process_param()
const, because it intentionally writes to one of them in the case
where it's the argument to -pw (in the vain hope of being at least
slightly friendly to 'ps'), so elsewhere I had to temporarily
dupstr() something for the sake of passing it to that function
- I had to invent a silly parallel version of const_cmp() so I could
pass const string literals in to lookup functions.
- stripslashes() in pscp.c and psftp.c has the annoying strchr nature
This change attempts to reinstate as a universal property something
which was sporadically true of the ad-hockery that came before
toplevel callbacks: that if there's a _very long_ queue of things to
be done through the callback mechanism, the doing of them will be
interleaved with re-checks of other event sources, which might (e.g.)
cause a flag to be set which makes the next callback decide not to do
anything after all.
[originally from svn r10040]
This is a little like schedule_timer, in that the callback you provide
will be run from the top-level message loop of whatever application
you're in; but unlike the timer mechanism, it will happen
_immediately_.
The aim is to provide a general way to avoid re-entrance of code, in
cases where just _doing_ the thing you want done is liable to trigger
a confusing recursive call to the function in which you came to the
decision to do it; instead, you just request a top-level callback at
the message loop's earliest convenience, and do it then.
[originally from svn r10019]
First, make absolute times unsigned. This means that it's safe to
depend on their overflow behaviour (which is undefined for signed
integers). This requires a little extra care in handling comparisons,
but I think I've correctly adjusted them all.
Second, functions registered with schedule_timer() are guaranteed to be
called with precisely the time that was returned by schedule_timer().
Thus, it's only necessary to check these values for equality rather than
doing risky range checks, so do that.
The timing code still does lots that's undefined, unnecessary, or just
wrong, but this is a good start.
[originally from svn r9667]
The previous platform-dependent ifdefs, switching between a system
which tried to cope with spurious callbacks (which I'd observed on
Windows) and one which tried to cope with system clock jumps (which
can happen on Unix, if you use gettimeofday) have been completely
removed, and replaced with a much simpler approach which just copes
with system clock jumps by triggering any timers immediately.
None of the resulting effects should be catastrophic (the worst thing
might be the waste of CPU in a spurious rekey, but as long as the
system clock isn't jumping around _all_ the time that's hardly
critical) and in any case the Unix port has had a long-standing oddity
involving occasional lockups if pterm or PuTTY runs for too long,
which hopefully this should replace with a much less bad failure mode.
And the code is much simpler, which is not to be sneezed at.
[originally from svn r9528]
remembered to do before! Also some related fixes, such as that after
we do so we should immediately stop selecting on the socket in
question.
[originally from svn r9363]
allocated type.
The main reason for this is to stop it from taking up a fixed large
amount of space in every 'struct value' subunion in conf.c, although
that makes little difference so far because Filename is still doing
the same thing (and is therefore next on my list). However, the
removal of its arbitrary length limit is not to be sneezed at.
[originally from svn r9314]
I think I have to consider this to be a separate but related change to
the wishlist item 'pscp-filemodes'; that was written before the Unix
port existed, and referred to the ability to configure the permissions
used for files copied from Windows to Unix - which is still not done.
[originally from svn r9260]
'Config' in putty.h, which stores all PuTTY's settings and includes an
arbitrary length limit on every single one of those settings which is
stored in string form. In place of it is 'Conf', an opaque data type
everywhere outside the new file conf.c, which stores a list of (key,
value) pairs in which every key contains an integer identifying a
configuration setting, and for some of those integers the key also
contains extra parts (so that, for instance, CONF_environmt is a
string-to-string mapping). Everywhere that a Config was previously
used, a Conf is now; everywhere there was a Config structure copy,
conf_copy() is called; every lookup, adjustment, load and save
operation on a Config has been rewritten; and there's a mechanism for
serialising a Conf into a binary blob and back for use with Duplicate
Session.
User-visible effects of this change _should_ be minimal, though I
don't doubt I've introduced one or two bugs here and there which will
eventually be found. The _intended_ visible effects of this change are
that all arbitrary limits on configuration strings and lists (e.g.
limit on number of port forwardings) should now disappear; that list
boxes in the configuration will now be displayed in a sorted order
rather than the arbitrary order in which they were added to the list
(since the underlying data structure is now a sorted tree234 rather
than an ad-hoc comma-separated string); and one more specific change,
which is that local and dynamic port forwardings on the same port
number are now mutually exclusive in the configuration (putting 'D' in
the key rather than the value was a mistake in the first place).
One other reorganisation as a result of this is that I've moved all
the dialog.c standard handlers (dlg_stdeditbox_handler and friends)
out into config.c, because I can't really justify calling them generic
any more. When they took a pointer to an arbitrary structure type and
the offset of a field within that structure, they were independent of
whether that structure was a Config or something completely different,
but now they really do expect to talk to a Conf, which can _only_ be
used for PuTTY configuration, so I've renamed them all things like
conf_editbox_handler and moved them out of the nominally independent
dialog-box management module into the PuTTY-specific config.c.
[originally from svn r9214]
strings more rigorously, and then we look up the local X authority
data in .Xauthority _ourself_ rather than delegating to an external
xauth program. This is (negligibly) more efficient on Unix, assuming
I haven't got it wrong in some subtle way, but its major benefit is
that we can now support X authority lookups on Windows as well
provided the user points us at an appropriate X authority file in
the standard format. A new Windows-specific config option has been
added for this purpose.
[originally from svn r8305]
-Werror, of course) about shifting by more than the range of a data
type. They only appeared in `if' statements testing sizeof(off_t),
but gcc warns even when the code is unreachable. I've removed the
conditional code (the general case should still work even on 32-bit
machines), and hacked each shift by 32 into a pair of shifts by 16.
Note that the gcc warning is not just a helpful indication that you
may be using the wrong data type; it's actually pointing out ANSI-
undefined behaviour in shifting a signed integer beyond the size of
its type.
[originally from svn r6789]
we set _FILE_OFFSET_BITS to 64 on the compiler command line (via mkfiles.pl),
and on Windows we use SetFilePointer and GetFileSize to cope with 64-bit sizes
where possible. Not tested on Win9x.
[originally from svn r6783]
abstracted out; replace loops structured around a single interaction
per loop with less tortuous code (fixes: `ki-multiprompt-crash',
`ssh1-bad-passphrase-crash'; makes `ssh2-password-expiry' and
`proxy-password-prompt' easier).
The new interaction abstraction has a lot of fields that are unused in
the current code (things like window captions); this is groundwork for
`gui-auth'. However, ssh.c still writes directly to stderr; that may
want to be fixed.
In the GUI apps, user interaction is moved to terminal.c. This should
make it easier to fix things like UTF-8 username entry, although I
haven't attempted to do so. Also, control character filtering can be
tailored to be appropriate for individual front-ends; so far I don't
promise anything other than not having made it any worse.
I've tried to test this fairly exhaustively (although Mac stuff is
untested, as usual). It all seems to basically work, but I bet there
are new bugs. (One I know about is that you can no longer make the
PuTTY window go away with a ^D at the password prompt; this should be
fixed.)
[originally from svn r6437]
[this svn revision also touched putty-wishlist]
<sys/time.h>. Cope with this. Where <sys/select.h> _is_ available, though,
use it (since it's where POSIX puts select()). Problem reported by Mike
Protts.
[originally from svn r6310]
Unix Plink sends everything sensible it can find, and it's fully configurable
from the GUI.
I'm not entirely sure about the precise set of modes that Unix Plink should
look at; informed tweaks are welcome.
Also the Mac bits are guesses (but trivial).
[originally from svn r5653]
[this svn revision also touched putty-wishlist]
in question vary per OS: on Windows the problem is that WM_TIMER
sometimes goes off too early, so that GetTickCount() is right and
the callback time is wrong, whereas on Unix the problem is that my
GETTICKCOUNT implementation comes from the system clock which means
it can change suddenly and non-monotonically if the sysadmin is
messing about (meaning that the timing of callbacks from GTK or
select timeouts is _more_ likely to be right than GETTICKCOUNT).
This checkin provides band-aid workarounds for both problems, which
aren't pretty but ought to at least prevent catastrophic assertion
failure.
[originally from svn r5556]
timing shakeup: just running `psftp' caused the net/stdin select
loop (on both Unix and Windows) to get confused at the lack of any
network connection and give up immediately. Should now be fixed.
[originally from svn r4993]
