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

[Stefan Roese]

Hi Simon,

On 10.05.2015 16:48, Simon Glass wrote:
> On 7 May 2015 at 06:13, Stefan Roese <sr at denx.de> wrote:
>> 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.
>>
>> Signed-off-by: Stefan Roese <sr at denx.de>
>> Cc: Masahiro Yamada <yamada.masahiro at socionext.com>
>> Cc: Simon Glass <sjg at chromium.org>
>> ---
>>
>>   scripts/kconfig/confdata.c | 20 +++++++++-----------
>>   scripts/kconfig/symbol.c   | 43 -------------------------------------------
>>   2 files changed, 9 insertions(+), 54 deletions(-)
>
> This looks right to me. But I do see one problem - the default string
> for CONFIG_AUTOBOOT_PROMPT appears as:
>
> "Autoboot in %d secondsn"
>
> so something is still removing the \ in the Kconfig default;

Right. Thanks for spotting. I'll fix this in v3.

Thanks,
Stefan