And one for me, for the much changed keyboard stuff.

Each leading tab is converted to two tabs, and any leading four spaces
is converted to one tab.  The intended tab size (for keeping most lines
within 80 columns) is now four.

In the tiny version, do_prompt() will now have an extra NULL
parameter, which will cost maybe twenty extra bytes of code.
That is acceptable when it saves thirty lines in the source.

The basic idea is that the cursor is always off, except when it needs
to be on: when waiting for text input, and in a few other cases: when
something was searched and found in the help viewer, and in the file
browser when option -g is in effect.

This fixes https://savannah.gnu.org/bugs/?51923

.
Reported-by: Mike Frysinger <vapier@gentoo.org>

Without them, nano still compiles for me, with everything enabled,
even when using --enable-debug, --enable-utf8, and --with-slang.

Include the shortcut for 'Uncut' into most menus, and add an uncut
function for the status bar, so that it becomes possible to paste
the first line of the cutbuffer at any text-input prompt.

This fulfills https://savannah.gnu.org/bugs/?48501

.
Requested-by: Benno Schulenberg <bensberg@telfort.nl>
Signed-off-by: Rishabh Dave <rishabhddave@gmail.com>

This matches the style in the rest of the code.

Add missing spaces, remove excess spaces, and
replace groups of indentation spaces with tabs.

Also, trim some comments and avoid an unused-variable warning.

The bottomwin has just been refreshed by update_the_statusbar(),
and it should not be the responsibility of the prompt routines
to keep the edit window up to date, as they don't write anything
there.

Allow the user to search in a help text with ^W and M-W.

Achieve this by not writing the help text directly to the screen
but first writing it to a temporary file and then opening this file
in a new buffer, and treating it specially: the normal file-reading
feedback is suppressed, the titlebar shows the headline of the text,
the cursor is hidden, and the menu is limited to just the up and down
movements and searching.

This fulfills https://savannah.gnu.org/bugs/?28994

.
Signed-off-by: Rishabh Dave <rishabhddave@gmail.com>

And in the bargain avoid a duplicate call of strlenpt(prompt).

The interval 2013-2017 for the Free Software Foundation is valid
because in those years there were releases with changes by either
Chris or David, and the GNU maintainers guide advises to mention
a new year in all files of a package, not just in the ones that
actually changed, and be done with it for the rest of the year.

Verify at startup that the number is not too small.

Rename some variables in the process, and remove two cluttering asserts.

These improvements will eventually make do_home() and do_end() take
parameters.  Since the global function lists can hold only functions
without parameters, preemptively add do_home_void() and do_end_void(),
and make the global function lists use them.

Most of these variables are freed moments later -- reallocating
them is thus a waste of time.

The conditionalizing saved negligible amounts of space, of memory, and
of speed.

This disallows entering a verbatim ^J (0x0A) when typing text or
search terms, and disallows a verbatim ^@ (0x00) when typing a
filename.  Nano beeps when the disallowed code is attempted.

This addresses https://savannah.gnu.org/bugs/?49897.

A KEY_WINCH does not need to be separately treated since the basic
action for anything that is not recognized at the yes-no prompt is:
to continue.

Also at the yes-no prompt, a 0x0A byte should be displayed as a ^J
instead of splitting the prompt bar in two and spreading it over
two lines.

This fixes https://savannah.gnu.org/bugs/?49934.

And certainly don't return zero when the key wouldn't have been found,
because that would have meant jumping a word to the right.

Also, swap the logic around, to use less braces.

And which normally is just some ten or twenty characters long, and
never gets wildly overallocated.

But do it correctly this time: don't switch it on when replacing.

None of the prompts offer a total-refresh shortcut -- only the
edit window, the help viewer, and the file browser provide this.

There is no need for that -- it just causes flicker.

This fixes https://savannah.gnu.org/bugs/?49742.