Caused an embarrassing failure just now trying to run the test program
from a command prompt - I had Return still held down by the time it
started up, and my release of it immediately terminated input :-)
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
I've written my own analogue of OpenSSH's ssh-askpass. At the moment,
it's contained inside Pageant proper, though it could easily be
compiled into a standalone binary as well or instead.
Unlike OpenSSH's version, I don't use a GTK edit box; instead I just
process key events myself and append them to a buffer. The big
advantage of doing this is that I can arrange for ^W and ^U to
function as they do in terminal line editing, i.e. delete a word or
delete the whole line.
^W in particular is really valuable when typing a multiple-word
passphrase unseen. If you feel yourself making the kind of typo in
which you're not sure if you pressed six keys or just five, you can
hit ^W and restart just that word, without either having to go right
back to the beginning or carry on and see if you feel lucky.
A delete-word function would of course be an information leak in even
an obscured edit box (displaying a blob per character), so instead I
give a visual acknowledgment of keypresses by a more ad-hoc means: I
display three lights in the box, and every meaningful keypress turns
off the currently active one and instead turns on a randomly selected
one of the others. (So the lit light doesn't even indicate _mod 3_ how
many keys have been pressed.)
