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'!
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.
After the recent Seat and LogContext revamps, _nearly_ all the
remaining uses of the type 'Frontend' were in terminal.c, which needs
all sorts of interactions with the GUI window the terminal lives in,
from the obvious (actually drawing text on the window, reading and
writing the clipboard) to the obscure (minimising, maximising and
moving the window in response to particular escape sequences).
All of those functions are now provided by an abstraction called
TermWin. The few remaining uses of Frontend after _that_ are internal
to a particular platform directory, so as to spread the implementation
of that particular kind of Frontend between multiple source files; so
I've renamed all of those so that they take a more specifically named
type that refers to the particular implementation rather than the
general abstraction.
So now the name 'Frontend' no longer exists in the code base at all,
and everywhere one used to be used, it's completely clear whether it
was operating in one of Frontend's three abstract roles (and if so,
which), or whether it was specific to a particular implementation.
Another type that's disappeared is 'Context', which used to be a
typedef defined to something different on each platform, describing
whatever short-lived resources were necessary to draw on the terminal
window: the front end would provide a ready-made one when calling
term_paint, and the terminal could request one with get_ctx/free_ctx
if it wanted to do proactive window updates. Now that drawing context
lives inside the TermWin itself, because there was never any need to
have two of those contexts live at the same time.
(Another minor API change is that the window-title functions - both
reading and writing - have had a missing 'const' added to their char *
parameters / return values.)
I don't expect this change to enable any particularly interesting new
functionality (in particular, I have no plans that need more than one
implementation of TermWin in the same application). But it completes
the tidying-up that began with the Seat and LogContext rework.
In the very old days, when PuTTY was new and computers were slow, I
tried to implement a feature where scrolling the window would be
implemented using a fast rectangle-copy GDI operation, rather than an
expensive character-by-character redraw of all the changed areas.
It never quite worked right, and I ended up conditioning it out on
Windows, and never even tried to implement it on GTK. It's now been
sitting around unused for so long that I think it's no longer worth
keeping in the code at all - if I tried to put it back in, it surely
wouldn't even compile, and would need rewriting from scratch anyway.
Disturbingly, it looks as if I _tried_ to re-enable it at one point,
in that there was a '#define OPTIMISE_IS_SCROLL 1' in putty.h - but
that never had any effect, because the macro name is misspelled. All
the #ifdefs are for 'OPTIMISE_SCROLL', without the 'IS'. So despite
appearances, it really _has_ been conditioned out all along!
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.
Nearly every part of the code that ever handles a full backend
structure has historically done it using a pair of pointer variables,
one pointing at a constant struct full of function pointers, and the
other pointing to a 'void *' state object that's passed to each of
those.
While I'm modernising the rest of the code, this seems like a good
time to turn that into the same more or less type-safe and less
cumbersome system as I'm using for other parts of the code, such as
Socket, Plug, BinaryPacketProtocol and so forth: the Backend structure
contains a vtable pointer, and a system of macro wrappers handles
dispatching through that vtable.
Same principle again - the more of these structures have globally
visible tags (even if the structure contents are still opaque in most
places), the fewer of them I can mistake for each other.
That's one fewer anonymous 'void *' which might be accidentally
confused with some other pointer type if I misremember the order of
function arguments.
While I'm here, I've made its pointer-nature explicit - that is,
'Ldisc' is now a typedef for the structure type itself rather than a
pointer to it. A stylistic change only, but it feels more natural to
me these days for a thing you're going to eventually pass to a 'free'
function.
This causes the previous graphic character to be displayed another Pn
times (defaulting to 1, as usual). I just found out about it because
Ubuntu 18.04's ncurses expects it to be honoured.
According to all-escapes, REP is only supposed to be used when the
thing immediately preceding it in the terminal data stream _is_ a
printing character, and if not, then the behaviour is undefined. But
'undefined' is good enough for me to do the simple thing of just
remembering the last graphic character no matter whether anything else
has intervened since then.
To avoid DoS attacks using this escape sequence with a really huge Pn,
I clamp the value at the total size of the screen. There might be ways
to do that with more finesse (e.g. reduce it mod the width so that the
screen ends up looking the way it should even for huge parameters, or
reduce it even further if we notice the terminal isn't in wrapping
modes), but this will do for now.
Thanks to Jiri Kaspar for sending this patch (apart from the new docs
section, which is in my own words), which implements a feature we've
had as a wishlist item ('utf8-plus-vt100') for a long time.
I was actually surprised it was possible to implement it in so few
lines of code! I'd forgotten, or possibly never noticed in the first
place, that even in UTF-8 mode PuTTY not only accepts but still
_processes_ all the ISO 2022 control sequences and shift characters,
and keeps running track of all the same state in term->cset and
term->cset_attrs that it tracks in IS0-2022-enabled modes. It's just
that in UTF-8 mode, at the very last minute when a character+attribute
pair is about to be written into the terminal's character buffer, it
deliberately ignores the contents of those variables.
So all that was needed was a new flag checked at that last moment
which causes it not quite to ignore them after all, and bingo,
utf8-plus-vt100 is supported. And it works no matter which ISO 2022
sequences you're using; whether you're using ESC ( 0 to select the
line drawing set directly into GL and ESC ( B to get back when you're
done, or whether you send a preliminary ESC ( B ESC ) 0 to get GL/GR
to be ASCII and line drawing respectively so you can use SI and SO as
one-byte mode switches thereafter, both work just as well.
This implementation strategy has a couple of consequences, which I
don't think matter very much one way or the other but I document them
just in case they turn out to be important later:
- if an application expecting this mode has already filled your
terminal window with lqqqqqqqqk, then enabling this mode in Change
Settings won't retroactively turn them into the line drawing
characters you wanted, because no memory is preserved in the screen
buffer of what the ISO 2022 state was when they were printed. So
the application still has to do a screen refresh.
- on the other hand, if you already sent the ESC ( 0 or whatever to
put the terminal _into_ line drawing mode, and then you turn on
this mode in Change Settings, you _will_ still be in line drawing
mode, because the system _does_ remember your current ISO 2022
state at all times, whether it's currently applying it to output
printing characters or not.
This stores the last text selected in _this_ terminal, regardless of
whether any other application has since taken back whatever system
clipboard we also copied it to. It's written unconditionally whenever
text is selected in terminal.c.
The main purpose of this will be that it's also the place that you can
go and find the data you need to write to a system clipboard in
response to an explicit Copy operation. But it can also act as a data
source for pastes in its own right, so you can use it to implement an
intra-window private extra clipboard if that's useful. (OS X Terminal
has one of those, so _someone_ at least seems to like the idea.)
This lays some groundwork for making PuTTY's cut and paste handling
more flexible in the area of which clipboard(s) it reads and writes,
if more than one is available on the system.
I've introduced a system of list macros which define an enumeration of
integer clipboard ids, some defined centrally in putty.h (at present
just a CLIP_NULL which never has any text in it, because that seems
like the sort of thing that will come in useful for configuring a
given copy or paste UI action to be ignored) and some defined per
platform. All the front end functions that copy and paste take a
clipboard id, and the Terminal structure is now configured at startup
to tell it which clipboard id it should paste from on a mouse click,
and which it should copy from on a selection.
However, I haven't actually added _real_ support for multiple X11
clipboards, in that the Unix front end supports a single CLIP_SYSTEM
regardless of whether it's in OS X or GTK mode. So this is currently a
NFC refactoring which does nothing but prepare the way for real
changes to come.
ATTR_REVERSE was being handled in the front ends, and was causing the
foreground and background colours to be switched. (I'm not completely
sure why I made that design decision; it might be purely historical,
but then again, it might also be because reverse video is one effect
on the fg and bg colours that must still be performed even in unusual
frontend-specific situations like display-driven monochrome mode.)
This affected both explicit reverse video enabled using SGR 7, and
also the transient reverse video arising from mouse selection. Thanks
to Markus Gans for reporting the bug in the latter, which when I
investigated it turned out to affect the former as well.
I spotted this myself while looking through the code in search of the
cause of the background-colour-erase bug: saving and restoring the
cursor via ESC 7 / ESC 8 ought to also save and restore the current
graphics rendition attributes including foreground and background
colour settings, but it was not saving and restoring the new
term->curr_truecolour along with term->curr_attr.
So there's now a term->save_truecolour to keep that in, and also a
term->alt_save_truecolour to take account of the fact that all the
saved cursor state variables get swapped out _again_ when switching
between the main and alternate screens.
(However, there is not a term->alt_truecolour to complete the cross
product, because the _active_ graphics rendition is carried over when
switching between the terminal screens; it's only the _saved_ one from
ESC 7 / ESC 8 that is saved separately. That's consistent with the
behaviour we've had all along for ordinary fg/bg colour selection.)
I know some users don't like any colour _at all_, and we have a
separate option to turn off xterm-style 256-colour sequences, so it
seems remiss not to have an option to disable true colour as well.
This is a heavily rewritten version of a patch originally by Lorenz
Diener; it was tidied up somewhat by Christian Brabandt, and then
tidied up more by me. The basic idea is to add to the termchar
structure a pair of small structs encoding 24-bit RGB values, each
with a flag indicating whether it's turned on; if it is, it overrides
any other specification of fg or bg colour for that character cell.
I've added a test line to colours.txt containing a few example colours
from /usr/share/X11/rgb.txt. In fact it makes quite a good demo to run
the whole of rgb.txt through this treatment, with a command such as
perl -pe 's!^\s*(\d+)\s+(\d+)\s+(\d+).*$!\e[38;2;$1;$2;$3m$&\e[m!' rgb.txt
Parameters are now accumulated in unsigned integers and carefully checked
for overflow (which is turned into saturation). Things that consume them
now have explicit range checks (again, saturating) to ensure that their
inputs are sane. This should make it much harder to cause overflow by
supplying ludicrously large numbers.
Fixes two bugs found with the help of afl-fuzz. One of them may be
exploitable and is CVE-2015-5309.
In r10020 I carefully reimplemented using timing.c and callback.c the
same policy for large pastes that the previous code appeared to be
implementing ad-hoc, which included a 450ms delay between sending
successive lines of pasted text if no visible acknowledgment of the
just-sent line (in the form of a \n or \r) came back from the
application.
However, it turns out that that *wasn't* what the old code was doing.
It *would* have done that, but for the bug that it never actually set
the 'last_paste' variable, and never has done since it was first
introduced way back in r516! So the policy I thought had been in force
forever has in fact only been in force since I unwittingly fixed that
bug in r10020 - and it turns out to be a bad idea, breaking pastes
into vi in particular.
So I've removed the timed paste code completely, on the basis that
it's never actually worked and nobody seems to have been unhappy about
that. Now we still break large pastes into separate lines and send
them in successive top-level callbacks, and the user can still press a
key to interrupt a paste if they manage to catch it still going on,
but there's no attempted *delay* any more.
(It's possible that what I *really* ought to be doing is calling
back->sendbuffer() to see whether the backend is consuming the data
pasted so far, and if not, deferring the rest of the paste until the
send buffer becomes smaller. Then we could have pasting be delayed by
back-pressure from the recipient, and still manually interruptible
during that delay, but not have it delayed by anything else. But what
we have here should at least manage to be equivalent to the *actual*
rather than the intended old policy.)
[originally from svn r10041]
[r516 == 0d5d39064a]
[r10020 == 7be9af74ec]
I've removed the ad-hoc front-end bodgery in the Windows and GTK ports
to arrange for term_paste to be called at the right moments, and
instead, terminal.c itself deals with knowing when to send the next
chunk of pasted data using a combination of timers and the new
top-level callback mechanism.
As a happy side effect, it's now all in one place so I can actually
understand what it's doing! It turns out that what all that confusing
code was up to is: send a line of pasted data, and delay sending the
next line until either a CR or LF is returned from the server
(typically indicating that the pasted text has been received and
echoed) or 450ms elapse, whichever comes first.
[originally from svn r10020]
xterm mouse tracking, both supported by the current up-to-date xterm
(288). They take the form of two new DEC terminal modes, 1006 and
1015, which do not in themselves _enable_ mouse tracking but they
modify the escape sequences sent if mouse tracking is enabled in the
usual way.
[originally from svn r9752]
which text pasted into the terminal is preceded and followed by
special function-key-like escape sequences ESC[200~ and ESC[201~ so
that the application can identify it and treat it specially (e.g.
disabling auto-indent-same-as-previous-line in text editors). Enabled
and disabled by ESC[?2004h and ESC[?2004l, and of course off by
default.
[originally from svn r9412]
'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]
transformed back and forth according to the character position
permutation output from the bidi algorithm. I was expecting that to
be a lot harder.
[originally from svn r4915]
which pretty much any module can call to request a call-back in the
future. So terminal.c can do its own handling of blinking, visual
bells and deferred screen updates, without having to rely on
term_update() being called 50 times a second (fixes: pterm-timer);
and ssh.c and telnet.c both invoke a new module pinger.c which takes
care of sending keepalives, so they get sent uniformly in all front
ends (fixes: plink-keepalives, unix-keepalives).
[originally from svn r4906]
[this svn revision also touched putty-wishlist]
array of each `termline' structure now contains optional additional
entries after the normal number of columns, which are used to chain
a linked list of combining characters off any primary termchar that
needs it. This means we support arbitrarily many combining
characters per cell (unlike xterm's hard limit of 2).
Cut and paste works correctly (selecting a character cell containing
multiple code points causes all those code points to be cut and
pasted). Display works by simply overlaying all the relevant
characters on top of one another; this is good enough for Unix
(xterm does the same thing), and mostly seems OK for Windows except
that the Windows Unicode fonts have a nasty habit of not containing
most of the combining characters and thus overlaying an
unknown-code-point box on your perfectly good base glyph.
I had no idea how to add support in the Mac do_text(), so I've
simply stuck in an assertion that will trigger the first time a
combining character is displayed, and hopefully this will bite
someone with the clue to fix it.
[originally from svn r4622]
The active terminal screen is no longer an array of `unsigned long'
encoding 16-bit Unicode plus 16 attribute bits. Now it's an array of
`termchar' structures, which currently have 32-bit Unicode and 32
attribute bits but which will probably expand further in future.
To prevent bloat of the memory footprint, I've introduced a mostly
RLE-like compression scheme for storing scrollback: each line is
compressed into a compact (but hard to modify) form when it moves
into the term->scrollback tree, and is temporarily decompressed when
the user wants to scroll back over it. My initial tests suggest that
this compression averages about 1/4 of the previous (32 bits per
character cell) data size in typical output, which means this is an
improvement even without counting the new ability to extend the
information stored in each character cell.
Another beneficial side effect is that the insane format in which
Unicode was passed to front ends through do_text() has now been
rendered sane.
Testing is incomplete; this _may_ still have instabilities. Windows
and Unix front ends both seem to work as far as I've looked, but I
haven't yet looked very hard. The Mac front end I've edited (it
seemed obvious how to change it) but I can't compile or test it.
As an immediate functional effect, the terminal emulator now
supports full 32-bit Unicode to whatever extent the host platform
allows it to. For example, if you output a 4-or-more-byte UTF-8
character in Unix pterm, it will not display it properly, but it
will correctly paste it back out in a UTF8_STRING selection. Windows
is more restricted, sadly.
[originally from svn r4609]
being able to be a PuTTY as well as a pterm. In the process I've
also moved icky things like actually reading from the pty fd and
printing the `terminated on signal' messages into pty.c where they
obviously should have been in the first place. Also there's been one
interesting repercussion in the terminal code: terminal.c's
from_backend now calls term_out() directly rather than expecting the
front end to call it afterwards. This has had the entertaining side
effect of fixing a Windows-specific bug whereby activity in a port
forwarding through a PuTTY with a blinking cursor caused the cursor
to blink to ON (!!!!). So, a surprisingly far-reaching checkin as it
turns out...
[originally from svn r3017]
malloc functions, which automatically cast to the same type they're
allocating the size of. Should prevent any future errors involving
mallocing the size of the wrong structure type, and will also make
life easier if we ever need to turn the PuTTY core code from real C
into C++-friendly C. I haven't touched the Mac frontend in this
checkin because I couldn't compile or test it.
[originally from svn r3014]
a marker which defines everything before it as `permanent'
scrollback and everything after it as `temporary'; only temporary
scrollback lines are returned to the main screen when the window
height is increased. Screen clears mark the lines pushed into the
scrollback as permanent; so lines explicitly cleared off the screen
by ESC[2J are never returned to it by mistake. This patch also fixes
the incorrect state the primary screen is left in when the window is
resized while the alternate screen is active.
[originally from svn r2923]
clears, and also to temporarily push the primary screen contents
into the scrollback while the alternate screen is active and bring
it back afterwards.
[originally from svn r2910]
combining adjacent ones for the same region, and runs them all in do_paint.
I'm not sure it's entirely right, but it works on my Mac in every case I've
tested.
[originally from svn r2763]
just done this the very simple way - bundle all the globals into a
data structure and pass pointers around. One particularly ugly wart
is that wc_to_mb now takes a pointer to this structure as an
argument (optional, may be NULL, and unused in any Unicode layer
that's even marginally less of a mess than the Windows one). I do
need to do this properly at some point, but for now this should just
about be adequate. As usual, the Mac port has not been updated.
[originally from svn r2592]
and term_reconfig() now passes in a new structure which is copied
over the top. This means that the old and new structures can be
compared, and the _current_ as well as default states of auto wrap
mode, DEC origin mode, BCE, blinking text and character classes can
be conveniently reconfigured in mid-session without requiring a
terminal reset.
[originally from svn r2557]
ignore when breaking text into runs for display, and implement setting this
on Mac (other ports just use 0xffffffff).
We don't use DeviceLoop for this any more because Apple Technical Q&A
QA1024 says we shouldn't. Unlike their example, we don't depend on the
Display Manager's being present either.
[originally from svn r2264]
absent, and also (I think) all the frontend request functions (such
as request_resize) take a context pointer, so that multiple windows
can be handled sensibly. I wouldn't swear to this, but I _think_
that only leaves the Unicode stuff as the last stubborn holdout.
[originally from svn r2147]
each backend now stores all its internal variables in a big struct,
and each backend function gets a pointer to this struct passed to
it. This still isn't the end of the work - lots of subsidiary things
still use globals, notably all the cipher and compressor modules and
the X11 forwarding authentication stuff. But ssh.c itself has now
been transformed, and that was the really painful bit, so from here
on it all ought to be a sequence of much smaller and simpler pieces
of work.
[originally from svn r2127]
Simon Tatham
Ben Harris
Jacob Nevins