[U-Boot] [PATCH v1 1/4] Kconfig: Enable usage of escape char '\' in string values

Masahiro Yamada
2015-05-07T12:41:15Z

Hi Stefan,

2015-05-07 21:13 GMT+09:00 Stefan Roese <sr@denx.de>:
> I might have missed something, but I failed to use the escape char '\'
> in strings. To pass a printf format string like "foo %d bar\n" via
> Kconfig to the code.
>
> Right now its not possible to use the escape character '\' in Kconfig
> string values correctly to e.g. set this string value "test output\n".
> The '\n' will be converted to 'n'.
>
> The current implementation removes some of the '\' chars from the input
> string in conf_set_sym_val(). Examples:
>
> '\' -> ''
> '\\' -> '\'
> '\\\' -> '\'
> '\\\\' -> '\\'
> ...
>
> And then doubles the backslash chars in the output string in
> sym_escape_string_value(). Example:
>
> '\' -> '' -> ''
> '\\' -> '\' -> '\\'
> '\\\' -> '\' -> '\\'
> '\\\\' -> '\\' -> '\\\\'
> ...
>
> As you see in these examples, its impossible to generate a single '\'
> charater in the output string as its needed for something like '\n'.
>
> This patch now changes this behavior to not drop some backslashes in
> conf_set_sym_val() and to not add new backslashes in the resulting
> output string. Removing the function sym_escape_string_value()
> completely as its not needed anymore.

Interesting.
I did not know this behavior of strings in Kconfig.

I want to see the reaction from linux-kconfig ML.

--
Best Regards
Masahiro Yamada