Unify the similar build rules.

This supports 'make build_config', which builds scripts/kconfig/conf
but does not invoke it.

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

scripts/kconfig/conf.c line 39 defines the default of input_mode as
oldaskconfig. Hence, 'make config' works in the same way even without
the --oldaskconfig option given. Note this in the help message.

This will be helpful to unify build rules in Makefile in the next
commit.

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

scripts/kconfig/conf supports -? option to show the help message.
This is not wired up to Makefile, so nobody would notice this, but
it also shows 'invalid option' message.

  $ ./scripts/kconfig/conf -?
  ./scripts/kconfig/conf: invalid option -- '?'
  Usage: ./scripts/kconfig/conf [-s] [option] <kconfig-file>
  [option] is _one_ of the following:
    --listnewconfig         List new options
    --helpnewconfig         List new options and help text
    --oldaskconfig          Start a new configuration using a line-oriented program
    ...

The reason is the '?' is missing in the short option list passed to
getopt_long().

While I fixed this issue, I also changed the option '?' to 'h'.
I prefer -h (or --help, if a long option is also desired).

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

conf_askvalue() is only called for oldconfig, syncconfig, and
oldaskconfig. If it is called for other cases, it is a bug.

So, the code after the switch statement is unreachable.

Remove the dead code, and clean up the switch statement.

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

Unify the outer two if-conditionals into one. This decreases the
indent level by one.

Also, change the if-else blocks:

    if (input_mode == listnewconfig) {
            ...
    } else if (input_mode == helpnewconfig) {
            ...
    } else {
            ...
    }

into the switch statement.

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

Use the saved returned value of sym_get_string_value() instead of
calling it twice.

Signed-off-by: Mickaël Salaün <mic@linux.microsoft.com>
Link: https://lore.kernel.org/r/20210215181511.2840674-2-mic@digikod.net
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>

Commit c0f975af1745 ("kconfig: Support building mconf with vendor
sysroot ncurses") introduces a bug when HOSTCC contains parameters:
the whole command line is treated as the program name (with spaces
in it). Therefore, we have to remove the quotes.

Fixes: c0f975af1745 ("kconfig: Support building mconf with vendor sysroot ncurses")
Signed-off-by: Enrico Weigelt, metux IT consult <info@metux.net>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>

Linux 5.10 is out. Remove the 'kvmconfig' and 'xenconfig' shorthands
as previously announced.

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

Changes the final fallback path in the ncurses locator for mconf
to support host compilers with a non-default sysroot.

This is similar to the hardcoded search for ncurses under
'/usr/include', but can support compilers that keep their default
header and library directories elsewhere.

For nconfig, do nothing because the only vendor compiler I'm aware
of with this layout (Apple Clang) ships an ncurses version that's too
old for nconfig anyway.

Signed-off-by: John Millikin <john@john-millikin.com>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>

$(error-if,...) is expanded to an empty string. Currently, it relies on
eval_clause() returning xstrdup("") when all attempts for expansion fail,
but the correct implementation is to make do_error_if() return xstrdup("").

Fixes: 1d6272e6fe43 ("kconfig: add 'info', 'warning-if', and 'error-if' built-in functions")
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>