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58 Commits

Author SHA1 Message Date
Simon Tatham
1a7e4ec8d4 New centralised version of local line editing.
This takes over from both the implementation in ldisc.c and the one in
term_get_userpass_input, which were imperfectly duplicating each
other's functionality. The new version should be more consistent
between the two already, and also, it means further improvements can
now be made in just one place.

In the course of this, I've restructured the inside of ldisc.c by
moving the input_queue bufchain to the other side of the translation
code in ldisc_send. Previously, ldisc_send received a string, an
optional 'dedicated key' indication (bodgily signalled by a negative
length) and an 'interactive' flag, translated that somehow into a
combination of raw backend output and specials, and saved the latter
in input_queue. Now it saves the original (string, dedicated flag,
interactive flag) data in input_queue, and doesn't do the translation
until the data is pulled back _out_ of the queue. That's because the
new line editing system expects to receive something much closer to
the original data format.

The term_get_userpass_input system is also substantially restructured.
Instead of ldisc.c handing each individual keystroke to terminal.c so
that it can do line editing on it, terminal.c now just gives the Ldisc
a pointer to its instance of the new TermLineEditor object - and then
ldisc.c can put keystrokes straight into that, in the same way it
would put them into its own TermLineEditor, without having to go via
terminal.c at all. So the term_get_userpass_input edifice is only
called back when the line editor actually delivers the answer to a
username or password prompt.

(I considered not _even_ having a separate TermLineEditor for password
prompts, and just letting ldisc.c use its own. But the problem is that
some of the behaviour differences between the two line editors are
deliberate, for example the use of ^D to signal 'abort this prompt',
and the use of Escape as an alternative line-clearing command. So
TermLineEditor has a flags word that allows ldisc and terminal to set
it up differently. Also this lets me give the two TermLineEditors a
different vtable of callback functions, which is a convenient way for
terminal.c to get notified when a prompt has been answered.)

The new line editor still passes all the tests I wrote for the old
one. But it already has a couple of important improvements, both in
the area of UTF-8 handling:

Firstly, when we display a UTF-8 character on the terminal, we check
with the terminal how many character cells it occupied, and then if
the user deletes it again from the editing buffer, we can emit the
right number of backspace-space-backspace sequences. (The old ldisc
line editor incorrectly assumed all Unicode characters had terminal
with 1, partly because its buffer was byte- rather than character-
oriented and so it was more than enough work just finding where the
character _start_ was.)

Secondly, terminal.c's userpass line editor would never emit a byte in
the 80-BF range to the terminal at all, which meant that nontrivial
UTF-8 characters always came out as U+FFFD blobs!
2023-03-04 13:55:50 +00:00
Simon Tatham
5ade8c0047 ldisc: fix unwanted double-action of ^U.
In ldisc's line editing mode, pressing ^U is supposed to erase the
current unsent line rather than inserting a literal ^U into the
buffer. In fact, when using a non-Telnet backend, it erases the
line *and* inserts ^U into the buffer!

This happens because it shares a case handler with three other
disruptive control characters (^C, ^\, ^Z), which all also clear the
line-editing buffer before doing their various actions. But in
non-Telnet mode, their actions become literal insertion of themselves,
so the combined effect is to erase the line and them self-insert.

I'm not 100% convinced that was what I actually meant to do with those
characters. But it _certainly_ wasn't what I meant to do with ^U, so
that one at least I should fix right now!
2022-12-21 15:16:21 +00:00
Simon Tatham
04c1617f20 Formatting: realign labels and case/default statements.
My aim has always been to have those back-dented by 2 spaces (half an
indent level) compared to the statements around them, so that in
particular switch statements have distinct alignment for the
statement, the cases and the interior code without consuming two whole
indent levels.

This patch sweeps up all the violations of that principle found by my
bulk-reindentation exercise.
2022-08-03 20:48:46 +01:00
Simon Tatham
65270b56f0 free_prompts: deal with a reference from an Ldisc.
In a GUI app, when interactive userpass input begins, the Ldisc
acquires a reference to a prompts_t. If something bad happens to the
SSH connection (e.g. unexpected server-side closure), then all the SSH
layers will be destroyed, including freeing that prompts_t. So the
Ldisc will have a stale reference to it, which it might potentially
use.

To fix that, I've arranged a back-pointer so that prompts_t itself can
find the Ldisc's reference to it, and NULL it out on free. So now,
whichever of a prompts_t and an Ldisc is freed first, the link between
them should be cleanly broken.

(I'm not 100% sure this is absolutely necessary, in the sense of
whether a sequence of events can _actually_ happen that causes a stale
pointer dereference. But I don't want to take the chance!)
2021-09-16 13:55:10 +01:00
Simon Tatham
cd8a7181fd Complete rework of terminal userpass input system.
The system for handling seat_get_userpass_input has always been
structured differently between GUI PuTTY and CLI tools like Plink.

In the CLI tools, password input is read directly from the OS
terminal/console device by console_get_userpass_input; this means that
you need to ensure the same terminal input data _hasn't_ already been
consumed by the main event loop and sent on to the backend. This is
achieved by the backend_sendok() method, which tells the event loop
when the backend has finished issuing password prompts, and hence,
when it's safe to start passing standard input to backend_send().

But in the GUI tools, input generated by the terminal window has
always been sent straight to backend_send(), regardless of whether
backend_sendok() says it wants it. So the terminal-based
implementation of username and password prompts has to work by
consuming input data that had _already_ been passed to the backend -
hence, any backend that needs to do that must keep its input on a
bufchain, and pass that bufchain to seat_get_userpass_input.

It's awkward that these two totally different systems coexist in the
first place. And now that SSH proxying needs to present interactive
prompts of its own, it's clear which one should win: the CLI style is
the Right Thing. So this change reworks the GUI side of the mechanism
to be more similar: terminal data now goes into a queue in the Ldisc,
and is not sent on to the backend until the backend says it's ready
for it via backend_sendok(). So terminal-based userpass prompts can
now consume data directly from that queue during the connection setup
stage.

As a result, the 'bufchain *' parameter has vanished from all the
userpass_input functions (both the official implementations of the
Seat trait method, and term_get_userpass_input() to which some of
those implementations delegate). The only function that actually used
that bufchain, namely term_get_userpass_input(), now instead reads
from the ldisc's input queue via a couple of new Ldisc functions.

(Not _trivial_ functions, since input buffered by Ldisc can be a
mixture of raw bytes and session specials like SS_EOL! The input queue
inside Ldisc is a bufchain containing a fiddly binary encoding that
can represent an arbitrary interleaving of those things.)

This greatly simplifies the calls to seat_get_userpass_input in
backends, which now don't have to mess about with passing their own
user_input bufchain around, or toggling their want_user_input flag
back and forth to request data to put on to that bufchain.

But the flip side is that now there has to be some _other_ method for
notifying the terminal when there's more input to be consumed during
an interactive prompt, and for notifying the backend when prompt input
has finished so that it can proceed to the next stage of the protocol.
This is done by a pair of extra callbacks: when more data is put on to
Ldisc's input queue, it triggers a call to term_get_userpass_input,
and when term_get_userpass_input finishes, it calls a callback
function provided in the prompts_t.

Therefore, any use of a prompts_t which *might* be asynchronous must
fill in the latter callback when setting up the prompts_t. In SSH, the
callback is centralised into a common PPL helper function, which
reinvokes the same PPL's process_queue coroutine; in rlogin we have to
set it up ourselves.

I'm sorry for this large and sprawling patch: I tried fairly hard to
break it up into individually comprehensible sub-patches, but I just
couldn't tease out any part of it that would stand sensibly alone.
2021-09-14 13:19:33 +01:00
Simon Tatham
9f0e7d2915 Backends: notify ldisc when sendok becomes true. (NFC)
I've introduced a function ldisc_notify_sendok(), which backends
should call on their ldisc (if they have one) when anything changes
that might cause backend_sendok() to start returning true.

At the moment, the function does nothing. But in future, I'm going to
make ldisc start buffering typed-ahead input data not yet sent to the
backend, and then the effect of this function will be to trigger
flushing all that data into the backend.

Backends only have to call this function if sendok was previously
false: backends requiring no network connection stage (like pty and
serial) can safely return true from sendok, and in that case, they
don't also have to immediately call this function.
2021-09-14 11:23:20 +01:00
Simon Tatham
6b1154cc5b Remove ldisc.h.
It only had to be a header file because ldisc.c and ldiscucs.c had to
share the structure definition. But ldiscucs.c vanished a couple of
years ago in commit 71e42b04a5, so it's now fine to make the
Ldisc structure definition local to ldisc.c itself, the way it should
be.
2021-09-13 12:06:45 +01:00
Simon Tatham
cd3e917fd0 Remove assertion that len != 0 in ldisc_send.
A user reported another situation in which that assertion can fail: if
you paste text into the terminal that consists 100% of characters not
available in the CONF_line_codepage character set, then the
translation step generates the empty string as output, and that gets
passed to ldisc_send by term_paste without checking.

Previous bugs of this kind (see commits 4634cd47f7 and 43a63019f5)
were fixed by adding a check before calling ldisc_send. But in commit
4634cd47f7 I said that probably at some point the right fix would be
to remove the assertion in ldisc_send itself, so that passing len==0
becomes legal. (The assertion was there in the first place to catch
cases where len==0 was used with its obsolete special meaning of
signalling 'please update your status'.)

Well, I think it's finally time. The assertion is removed: it's now
legal again to call ldisc_send with an empty buffer, and its meaning
is no longer the archaic special thing, but the trivial one of sending
zero characters through the line discipline.
2020-06-14 10:17:20 +01:00
Simon Tatham
5d718ef64b Whitespace rationalisation of entire code base.
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.
2019-09-08 20:29:21 +01:00
Simon Tatham
e3a14e1ad6 Withdraw support for the DECEDM escape sequence.
Having decided that the terminal's local echo setting shouldn't be
allowed to propagate through to termios, I think the local edit
setting shouldn't either. Also, no other terminal emulator I know
seems to implement this sequence, and if you enable it, things get
very confused in general. I think it's generally better off absent; if
somebody turns out to have been using it, then we'll at least be able
to find out what it's good for.
2019-06-18 06:58:51 +01:00
Simon Tatham
e0a76971cc New array-growing macros: sgrowarray and sgrowarrayn.
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).
2019-02-28 20:15:38 +00:00
Simon Tatham
3214563d8e Convert a lot of 'int' variables to 'bool'.
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'!
2018-11-03 13:45:00 +00:00
Simon Tatham
1378bb049a Switch some Conf settings over to being bool.
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.
2018-11-03 13:45:00 +00:00
Simon Tatham
a6f1709c2f Adopt C99 <stdbool.h>'s true/false.
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.
2018-11-03 13:45:00 +00:00
Simon Tatham
b4c8fd9d86 New abstraction 'Seat', to pass to backends.
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.)
2018-10-11 19:58:42 +01:00
Simon Tatham
109df9f46b Remove frontend_keypress().
This was used by ldisc to communicate back to the front end that a key
had been pressed (or rather, that a keypress had caused a nonzero
amount of session input data). Its only nontrivial implementation was
in gtkwin.c, which used that notification to implement the Unix GUI's
"close window on keypress, if the session was already over" policy.

(Which in turn is Unix-specific, because the rationale is that
sometimes X servers don't have a functioning window manager, so it's
useful to have a way of telling any application to close without using
WM-provided facilities like a close button.)

But gtkwin.c doesn't need to be told by the ldisc that a keypress
happened - it's the one _sending_ those keypresses to ldisc in the
first place! So I've thrown away the three stub implementations of
frontend_keypress, removed the call to it in ldisc.c, and replaced it
with calls in gtkwin.c at all the points during keypress handling
that call ldisc_send.

A visible effect is that pterm's close-on-keypress behaviour will now
only trigger on an actual (input-generating) _keypress_, and not on
other input generation such as a paste action. I think that's an
improvement.
2018-10-11 18:14:05 +01:00
Simon Tatham
f4fbaa1bd9 Rework special-commands system to add an integer argument.
In order to list cross-certifiable host keys in the GUI specials menu,
the SSH backend has been inventing new values on the end of the
Telnet_Special enumeration, starting from the value TS_LOCALSTART.
This is inelegant, and also makes it awkward to break up special
handlers (e.g. to dispatch different specials to different SSH
layers), since if all you know about a special is that it's somewhere
in the TS_LOCALSTART+n space, you can't tell what _general kind_ of
thing it is. Also, if I ever need another open-ended set of specials
in future, I'll have to remember which TS_LOCALSTART+n codes are in
which set.

So here's a revamp that causes every special to take an extra integer
argument. For all previously numbered specials, this argument is
passed as zero and ignored, but there's a new main special code for
SSH host key cross-certification, in which the integer argument is an
index into the backend's list of available keys. TS_LOCALSTART is now
a thing of the past: if I need any other open-ended sets of specials
in future, I can add a new top-level code with a nicely separated
space of arguments.

While I'm at it, I've removed the legacy misnomer 'Telnet_Special'
from the code completely; the enum is now SessionSpecialCode, the
struct containing full details of a menu entry is SessionSpecial, and
the enum values now start SS_ rather than TS_.
2018-09-24 09:43:39 +01:00
Simon Tatham
8dfb2a1186 Introduce a typedef for frontend handles.
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.
2018-09-19 22:10:58 +01:00
Simon Tatham
eefebaaa9e Turn Backend into a sensible classoid.
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.
2018-09-19 22:10:58 +01:00
Simon Tatham
e72e8ebe59 Expose the Ldisc structure tag throughout the code.
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.
2018-09-19 22:10:57 +01:00
Simon Tatham
7babe66a83 Make lots of generic data parameters into 'void *'.
This is a cleanup I started to notice a need for during the BinarySink
work. It removes a lot of faffing about casting things to char * or
unsigned char * so that some API will accept them, even though lots of
such APIs really take a plain 'block of raw binary data' argument and
don't care what C thinks the signedness of that data might be - they
may well reinterpret it back and forth internally.

So I've tried to arrange for all the function call APIs that ought to
have a void * (or const void *) to have one, and those that need to do
pointer arithmetic on the parameter internally can cast it back at the
top of the function. That saves endless ad-hoc casts at the call
sites.
2018-05-26 09:22:43 +01:00
Simon Tatham
89da2ddf56 Giant const-correctness patch of doom!
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
2015-05-15 12:47:44 +01:00
Simon Tatham
c269dd0135 Move echo/edit state change functionality out of ldisc_send.
I'm not actually sure why we've always had back ends notify ldisc of
changes to echo/edit settings by giving ldisc_send(ldisc,NULL,0,0) a
special meaning, instead of by having a separate dedicated notify
function with its own prototype and parameter set. Coverity's recent
observation that the two kinds of call don't even have the same
requirements on the ldisc (particularly, whether ldisc->term can be
NULL) makes me realise that it's really high time I separated the two
conceptually different operations into actually different functions.

While I'm here, I've renamed the confusing ldisc_update() function
which that special operation ends up feeding to, because it's not
actually a function applying to an ldisc - it applies to a front end.
So ldisc_send(ldisc,NULL,0,0) is now ldisc_echoedit_update(ldisc), and
that in turn figures out the current echo/edit settings before passing
them on to frontend_echoedit_update(). I think that should be clearer.
2014-11-22 16:18:00 +00:00
Simon Tatham
068b67d2f6 Clarify when ldisc->term may be NULL.
Namely, any ldisc that you send actual data through should have a
terminal attached, because the ldisc editing/echoing system is
designed entirely for use with a terminal. The only time you can have
an ldisc with no terminal is when it's only ever used by the backend
to report changes to the front end in edit/echo status, e.g. by Unix
Plink.

Coverity spotted an oddity in ldisc_send which after a while I decided
would never have actually caused a problem, but OTOH I agree that it
was confusing, so now hopefully it's less so.
2014-11-22 15:25:38 +00:00
Simon Tatham
4db5c2899f Make calling term_nopaste() a cross-platform feature.
It was one of those things that went in ages ago on Windows and never
got replicated in the Unix front end. And it needn't be: ldisc.c is a
perfect place to put it, since it knows which of the data it's sending
is based on a keystroke and which is automatically generated, and it
also has access to the terminal context. So now a keypress can
interrupt a runaway paste on all platforms.

[originally from svn r10025]
2013-08-17 16:06:40 +00:00
Simon Tatham
a1f3b7a358 Post-release destabilisation! Completely remove the struct type
'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]
2011-07-14 18:52:21 +00:00
Simon Tatham
7531c7d3d4 Cast incoming characters to unsigned char to avoid accidental sign
extension. Since ldisc_send() uses bit 8 as an internal flag, we
shouldn't be setting it except when we really want to.

[originally from svn r8989]
2010-09-09 14:32:25 +00:00
Simon Tatham
fb7dd5a255 At last! After much delay, much faffing back and forth, and much
enhancement and fiddling, I have now massaged Arabeyes' first patch
into a form I'm happy to check in. Phew.

[originally from svn r4236]
2004-05-22 10:36:50 +00:00
Simon Tatham
09f7a8edbf Fix from yesterday's frontend-handle upheaval: ldisc calls
from_backend(), and must now pass its frontend handle rather than
its terminal handle.

[originally from svn r3106]
2003-04-12 09:19:09 +00:00
Simon Tatham
d36a4c3685 Introduced wrapper macros snew(), snewn() and sresize() for the
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]
2003-03-29 16:14:26 +00:00
Simon Tatham
73203bce79 Never pass a `char' to a ctype function. I had relied on gcc -Wall
letting me know about instances of this, but it turns out that my
ctype.h explicitly casts input values to `int' to evade the
`subscript has type char' warning, so it had been carefully not
letting me know! Found them all by compiling with a doctored
ctype.h, and hopefully fixed them all too.

[originally from svn r2927]
2003-03-11 09:30:31 +00:00
Simon Tatham
6aa4211f6e Remove all `enum'-typed variables from the Config structure.
Everything in there which is integral is now an actual int, which
means my forthcoming revamp of the config box will be able to work
with `int *' pointers without fear of doom.

[originally from svn r2733]
2003-01-27 18:02:24 +00:00
Ben Harris
694aafa071 Add the ability to close sessions. This adds *_free() functions to most
areas of the code.  Not all back-ends have been tested, but Telnet and SSH
behave reasonably.

Incidentally, almost all of this patch was written through Mac PuTTY,
admittedly over a Telnet connection.

[originally from svn r2615]
2003-01-15 23:30:21 +00:00
Ben Harris
d60ea36673 Add a Config * argument to ldisc_create(), and use it in place of the global
cfg throughout ldisc.c.  Not tested other than on Mac, but all other ports
just pass &cfg as this argument for now.

[originally from svn r2250]
2002-11-23 20:02:38 +00:00
Simon Tatham
948f95d5e8 Reorganised the Unicode layer somewhat: moved luni_send and
lpage_send out into the line discipline, making them _clients_ of
the Unicode layer rather than part of it. This means they can access
ldisc->term, which in turn means I've been able to remove the
temporary global variable `term'. We're slowly getting there.

[originally from svn r2143]
2002-10-26 11:08:59 +00:00
Simon Tatham
0b2523eeda Line discipline module now uses dynamically allocated data. Also
fixed one or two other minor problems.

[originally from svn r2141]
2002-10-26 10:16:19 +00:00
Simon Tatham
72ff571148 Major destabilisation, phase 2. This time it's the backends' turn:
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]
2002-10-25 11:30:33 +00:00
Simon Tatham
6e549a6db3 Oops - repercussions of the close-on-exit stuff which I forgot to
check in. I must stop doing my Unix checkins in the Unix subdir :-(

[originally from svn r2125]
2002-10-24 14:12:55 +00:00
Simon Tatham
0a80c983e2 Major destabilisation, phase 1. In this phase I've moved (I think)
all the global and function-static variables out of terminal.c into
a dynamically allocated data structure. Note that this does not yet
confer the ability to run more than one of them in the same process,
because other things (the line discipline, the back end) are still
global, and also in particular the address of the dynamically
allocated terminal-data structure is held in a global variable
`term'. But what I've got here represents a reasonable stopping
point at which to check things in. In _theory_ this should all still
work happily, on both Unix and Windows. In practice, who knows?

[originally from svn r2115]
2002-10-22 16:11:33 +00:00
Simon Tatham
6d0e9b205d First phase of porting. pterm now compiles and runs under Linux+gtk.
The current pty.c backend is temporarily a loopback device for
terminal emulator testing, the display handling is only just enough
to show that terminal.c is functioning, the keyboard handling is
laughable, and most features are absent. Next step: bring output and
input up to a plausibly working state, and put a real pty on the
back to create a vaguely usable prototype. Oh, and a scrollbar would
be nice too.
In _theory_ the Windows builds should still work fine after this...

[originally from svn r2010]
2002-10-09 18:09:42 +00:00
Simon Tatham
726f9dde7e Add a configurable option to make Return in Telnet send an ordinary
^M instead of the Telnet New Line code. Unix-type telnetds don't
care one way or the other; RDB claims some telnetds prefer Telnet
NL; and now someone has found one that can't deal with Telnet NL and
prefers ^M. Sigh.

[originally from svn r1520]
2001-12-29 17:21:26 +00:00
Simon Tatham
830c1ea580 Now that we can configure whether ^C and friends generate Telnet IP
and friends, we should honour the user's choice even in line editing
mode. In particular, Telnet talkers don't like us randomly spraying
Telnet IP whenever the user accidentally hits ^C, so this is not a
helpful default.

[originally from svn r1316]
2001-10-24 11:50:07 +00:00
Simon Tatham
39c3f9b8bc Fix pasting of newlines in local line editing mode. Possibly not a
very _good_ fix; something might want doing after the release.

[originally from svn r1277]
2001-09-19 20:07:15 +00:00
Simon Tatham
38b6d276d2 RDB: fix various UTF-8 glitches.
[originally from svn r1138]
2001-05-19 15:21:05 +00:00
Simon Tatham
26f1085038 RDB's Unicode patch. Fonts are now used in Unicode mode where
possible and we have a single unified means of trying to display any
Unicode code point. Instead of the various ad-hoc translation modes
we had before, we now have a single `codepage' option which allows
us to treat the incoming (and outgoing) text as any given character
set, and locally we map that to Unicode and back.

[originally from svn r1110]
2001-05-10 08:34:20 +00:00
Simon Tatham
e001f1533e From RDB: a patch to allow special keys (^C, ^Z, Delete, Return) to
send Telnet special sequences (Interrupt Process, Suspend, Erase
Char, End Of Line) instead of their ASCII equivalents. In particular
Return -> Telnet End Of Line is _always_ enabled irrespective of the
configuration, while the others are optional. Also in this patch, an
entertainingly ghastly use of `switch' to allow literal ^M^J to do
the same thing as magic-^M (the Return key) when in Raw protocol.

[originally from svn r1109]
2001-05-09 15:12:26 +00:00
Simon Tatham
3730ada5ce Run entire source base through GNU indent to tidy up the varying
coding styles of the various contributors! Woohoo!

[originally from svn r1098]
2001-05-06 14:35:20 +00:00
Simon Tatham
7a79df8fe6 Rethink the whole line discipline architecture. Instead of having
multiple switchable line disciplines, we now have a single unified
one which changes its behaviour based on option settings. Each
option setting can be suggested by the back end and/or the terminal
handler, and can be forcibly overridden by the configuration. Local
echo and local line editing are separate, independently switchable,
options.

[originally from svn r895]
2001-01-24 14:08:20 +00:00
Simon Tatham
bbbda4110b Created a shiny new abstraction for the socket handling. Has many
advantages:
 - protocol modules can call sk_write() without having to worry
   about writes blocking, because blocking writes are handled in the
   abstraction layer and retried later.
 - `Lost connection while sending' is a thing of the past.
 - <winsock.h> is no longer needed in most modules, because
   "putty.h" doesn't have to declare `SOCKET' variables any more,
   only the abstracted `Socket' type.
 - select()-equivalent between multiple sockets will now be handled
   sensibly, which opens the way for things like SSH port
   forwarding.

[originally from svn r744]
2000-10-23 10:32:37 +00:00
Simon Tatham
e32603347c Introduce a sane interface function, from_backend(), for backends to
use when they have data from the network. Replaces the utterly daft
inbuf / inbuf_head / term_out() interface, which only made sense
when feeding to terminal.c. (terminal.c now implements
from_backend() as a small function that gateways to the old
interface.)

As a side effect, from_backend() also has an `is_stderr' parameter,
so scp can once again separate the server's pronouncements on stderr
from the actual protocol progress on stdout.

[originally from svn r729]
2000-10-20 13:51:46 +00:00