That's not a failure outcome. The user asked for some information; we
printed it; nothing went wrong. Mission successful, so exit(0)!
I noticed this because it was sitting right next to some of the
usage() calls modified in the previous commit. Those also had the
misfeature of exiting with failure after successfully printing the
help, possibly due to confusion arising from the way that usage() was
_sometimes_ printed on error as well. But pgp_fingerprints() has no
such excuse. That one's just silly.
Converting a CmdlineArg straight to a Filename allows us to make the
filename out of the wide-character version of the string on Windows.
So now filenames specified on the command line should generally be
able to handle pathnames containing Unicode characters not in the
system code page.
This change also involves making some char pointers _into_ Filename
structs where they weren't previously: for example, the
'openssh_config_file' variable in Windows Pageant's WinMain().
This begins the process of enabling our Windows applications to handle
Unicode characters on their command lines which don't fit in the
system code page.
Instead of passing plain strings to cmdline_process_param, we now pass
a partially opaque and platform-specific thing called a CmdlineArg.
This has a method that extracts the argument word as a default-encoded
string, and another one that tries to extract it as UTF-8 (though it
may fail if the UTF-8 isn't available).
On Windows, the command line is now constructed by calling
split_into_argv_w on the Unicode command line returned by
GetCommandLineW(), and the UTF-8 method returns text converted
directly from that wide-character form, not going via the system code
page. So it _can_ include UTF-8 characters that wouldn't have
round-tripped via CP_ACP.
This commit introduces the abstraction and switches over the
cross-platform and Windows argv-handling code to use it, with minimal
functional change. Nothing yet tries to call cmdline_arg_get_utf8().
I say 'cross-platform and Windows' because on the Unix side there's
still a lot of use of plain old argv which I haven't converted. That
would be a much larger project, and isn't currently needed: the
_current_ aim of this abstraction is to get the right things to happen
relating to Unicode on Windows, so for code that doesn't run on
Windows anyway, it's not adding value. (Also there's a tension with
GTK, which wants to talk to standard argv and extract arguments _it_
knows about, so at the very least we'd have to let it munge argv
before importing it into this new system.)
message_box() previously differed from the real MessageBox API
function in that it permitted the user to provide a help context to be
used for a Help button in the dialog box.
Now it adds a second unusual ability: you can specify that the text
and caption strings are in UTF-8 rather than the system code page.
In the Windows API, there are two places you can get a command line in
the form of a single unsplit string. One is via the command-line
parameter to WinMain(); the other is by calling GetCommandLine(). But
the two have different semantics: the WinMain command line string is
only the part after the program name, whereas GetCommandLine() returns
the full command line _including_ the program name.
PuTTY has never yet had to parse the full output of GetCommandLine,
but I have plans that will involve it beginning to do so. So I need to
make sure the utility function split_into_argv() can handle it.
This is not trivial because the quoting convention is different for
the program name than for everything else. In the program's normal
arguments, parsed by the C library startup code, the convention is
that backslashes are special when they appear before a double quote,
because that's how you write a literal double quote. But in the
program name, backslashes are _never_ special, because that's how
CreateProcess parses the program name at the start of the command
line, and the C library must follow suit in order to correctly
identify where the program name ends and the arguments begin.
In particular, consider a command line such as this:
"C:\Program Files\Foo\"foo.exe "hello \"world\""
The \" in the middle of the program name must be treated as a literal
backslash, followed by a non-literal double quote which matches the
one at the start of the string and causes the space in 'Program Files'
to be treated as part of the pathname. But the same \" when it appears
in the subsequent argument is treated as an escaped double quote, and
turns into a literal " in the argument string.
This commit adds support for this special initial-word handling in
split_into_argv(), via an extra boolean argument indicating whether to
turn that mode on. However, all existing call sites set the flag to
false, because the new mode isn't needed _yet_. So there should be no
functional change.
This makes pterm.exe support the same (very small) subset of the
standard option collection that Unix pterm does. Namely, -load (which
won't do anything useful with a hostname to connect to, but is still
useful if you have a saved session containing configuration like
colours or default size or what have you), and also -sessionlog.
To make this work, I've had to move the 'tooltype' definition out of
window.c into {putty,pterm}.c, so that it can be defined differently
in the two.
save_screenshot() returns a dynamically allocated error message in
case of failure, and Coverity complained of a memory leak when it was
ignored in putty.c.
The memory leak is trivial, because we were about to terminate the
process with an error anyway. But it's a good point that I forgot to
report the error!
Not critical enough to fix on 0.77 (where Coverity found it), but we
might as well make it look sensible on main.
In the course of polishing up this dialog box, I'm going to want it to
actually do cryptographic things (such as checking validity of a
public key blob and printing its fingerprint), which means it will
need to link against SSH utility functions.
So I've moved the dialog-box setup and handling code out of config.c
into a new file in the ssh subdirectory and in the ssh library, where
those facilities will be conveniently available.
This also means that dialog-box setup code _won't_ be linked into
PuTTYtel or pterm (on either platform), so I've added a stub source
file to provide its entry-point function in those tools. Also,
provided a const bool to indicate whether that dialog is available,
which we use to decide whether to recognise that command-line option.
This causes PuTTY to bring up just the host CA configuration dialog
box, and shut down once that box is dismissed.
I can imagine it potentially being useful to users, but in the first
instance, I expect it to be useful to _me_, because it will greatly
streamline testing changes to the UI of that dialog!
Using a new screenshot-taking module I just added in windows/utils,
these new options allow me to start up one of the tools with
demonstration window contents and automatically save a .BMP screenshot
to disk. This will allow me to keep essentially the same set of demo
images and update them easily to keep pace with the current appearance
of the real tools as PuTTY - and Windows itself - both evolve.
This prepares the ground for a second essentially similarly-shaped
program reusing most of window.c but handling its command line and
startup differently. A couple of large parts of WinMain() to do with
backend selection and command-line handling are now subfunctions in a
separate file putty.c.
Also, our custom AppUserModelId is defined in that file, so that it
can vary with the client application.
