Just trivial cleanups.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>

Previously, optional bool choices met the following conditions
simultaneously:

 - sym_is_choice(sym)
 - sym_is_changeable(sym)
 - type == S_BOOLEAN

It no longer occurs since 6a1215888e23 ("kconfig: remove 'optional'
property support"). Remove the dead code.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>

This code previously displayed child symbols of the selected choice
member.

Since commit 7e3465f63a0a ("kconfig: do not reparent the menu inside
a choice block"), choice members never have child symbols, therefore
this is dead code.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>

The struct list_head is often embedded in other structures, while other
code is used in C functions.

By separating struct list_head into its own header, other headers are no
longer required to include the entire list.h.

This is similar to the kernel space, where struct list_head is defined
in <linux/types.h> instead of <linux/list.h>.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>

Separate out the duplicated code to mnconf-common.c.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>

A little more janitorial work after commit cf8e8658100d ("arch: Remove
Itanium (IA-64) architecture").

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Nicolas Schier <nicolas@fjasle.eu>

Menuconfig has a feature where you can "press the key in the (#) prefix
to jump directly to that location. You will be returned to the current
search results after exiting this new menu."

This commit adds this feature to nconfig, with almost identical code.

Signed-off-by: Jesse Taube <Mr.Bossman075@gmail.com>
Acked-by: Randy Dunlap <rdunlap@infradead.org>
Tested-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>

Make nconfig accept jk keybindings for movement in addition to arrow
keys.

Signed-off-by: Isak Ellmer <isak01@gmail.com>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>

If the user selects the very first entry in a page and performs a
search-up operation, or selects the very last entry in a page and
performs a search-down operation that will not succeed (e.g., via
[/]asdfzzz[Up Arrow]), nconf will never terminate searching the page.

The reason is that in this case, the starting point will be set to -1
or n, which is then translated into (n - 1) (i.e., the last entry of
the page) or 0 (i.e., the first entry of the page) and finally the
search begins. This continues to work fine until the index reaches 0 or
(n - 1), at which point it will be decremented to -1 or incremented to
n, but not checked against the starting point right away. Instead, it's
wrapped around to the bottom or top again, after which the starting
point check occurs... and naturally fails.

My original implementation added another check for -1 before wrapping
the running index variable around, but Masahiro Yamada pointed out that
the actual issue is that the comparison point (starting point) exceeds
bounds (i.e., the [0,n-1] interval) in the first place and that,
instead, the starting point should be fixed.

This has the welcome side-effect of also fixing the case where the
starting point was n while searching down, which also lead to an
infinite loop.

OTOH, this code is now essentially all his work.

Amazingly, nobody seems to have been hit by this for 11 years - or at
the very least nobody bothered to debug and fix this.

Signed-off-by: Mihai Moldovan <ionic@ionic.de>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>

This helper is the same as the sample code in the NCURSES HOWTO [1],
but it is over-engineering to be used for nconf.

I do not see any good reason to use the 'float' type just for the
division by 2.

All the call-sites pass a non-NULL pointer to the first argument,
so 'if (win == NULL) win = stdscr;' is dead code.

'if (startx != 0) x = startx;' is dead code because 'x' will be
overridden some lines below, by 'x = startx + (int)temp;'.

All the call-sites pass a non-zero value to the second argument,
so 'if (starty != 0)' is always true.

getyx(win, y, x) is also dead-code because both 'y' and 'x' are
overridden.

All the call-sites pass 0 to the third parameter, so 'startx' can
be removed.

All the call-sites pass a non-zero value to the fourth parameter,
so 'if (width == 0) width = 80;' is dead code.

The window will be refreshed later, so there is no need to call
refresh() in this function.

Change the type of the last parameter from 'chtype' to 'int' to be
aligned with the prototype, 'int wattrset(WINDOW *win, int attrs);'

I also slightly cleaned up the indentation style.

[1]: https://tldp.org/HOWTO/NCURSES-Programming-HOWTO/color.html

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>