Hi Stefan,
2015-05-15 16:13 GMT+09:00 Stefan Roese sr@denx.de:
Hi Masahiro,
On 13.05.2015 03:34, Masahiro Yamada wrote:
Hi, Simon, Stefan,
2015-05-12 7:41 GMT+09:00 Simon Glass sjg@chromium.org:
Hi Stefan,
On 11 May 2015 at 07:27, Stefan Roese mail@roese.nl wrote:
Hi Simon, Hi Masahiro,
On 11.05.2015 09:58, Stefan Roese wrote:
On 10.05.2015 16:48, Simon Glass wrote:
On 7 May 2015 at 06:13, Stefan Roese sr@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@denx.de > Cc: Masahiro Yamada yamada.masahiro@socionext.com > Cc: Simon Glass sjg@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.
I could easily change the default string in the Kconfig file to "Autoboot in %d seconds\n". This works. But its a different syntax regarding using the escape character backslash compared to editing the .config file or editing the string in "make menuconfig etc...". So I hesitate to "fix" it this way.
Unfortunately fixing this issue in the code is not that easy. At least not for me. As the default values of the "string values" are set in the conf_parse() function (in scripts/kconfig/zconf.y). And I really have absolutely no experience with yacc / bison. Perhaps one of you guys has a quick fix to make this default value of strings compatible again so that this additional '' is not needed in the Kconfig file?
Well I am familiar with those tools but I think Masahiro probably knows a lot more here.
I am not so familiar with Bison, and I am getting a bit busy these days. So, I cannot find time to take a close look. Sorry.
If Simon (or someone else) could follow it up, that'd be nice.
BTW, if you have already figured out that conf_parse() is the cause of the problem, you do not have to invoke Bison.
Bison does not touch the C part. conf_parse() is just copied verbatim from zconf.y to zconf.tab.c_shipped.
You can modify conf_parse() exactly in the same way in both of them.
Thanks. Did it and found that zconfparse() is responsible for this default value configuration / parsing. I must be missing something, but I fail to see where this function is really implemented:
$ git grep zconfparse scripts/kconfig/lkc.h:int zconfparse(void); scripts/kconfig/zconf.tab.c_shipped:#define yyparse zconfparse scripts/kconfig/zconf.tab.c_shipped: zconfparse(); scripts/kconfig/zconf.y: zconfparse();
Bison converts zconf.y into zconf.tab.c_shipped
You will notice the following part.
/* Substitute the variable and function names. */ #define yyparse zconfparse #define yylex zconflex
I think zconfparse was taken from the basename of zconf.y
And then, you will also notice the following part:
/*----------. | yyparse. | `----------*/
#ifdef YYPARSE_PARAM #if (defined __STDC__ || defined __C99__FUNC__ \ || defined __cplusplus || defined _MSC_VER) int yyparse (void *YYPARSE_PARAM) #else int yyparse (YYPARSE_PARAM) void *YYPARSE_PARAM; #endif #else /* ! YYPARSE_PARAM */ #if (defined __STDC__ || defined __C99__FUNC__ \ || defined __cplusplus || defined _MSC_VER) int yyparse (void) #else int yyparse ()
#endif #endif { int yystate; /* Number of tokens to shift before error messages enabled. */
"yyparse" is replaced with "zconfparse" by the prepreocessor, so this is the implementation of zconfparse(), and it is the parser generated by Bison.
I think it is almost impossible to read the generated parser directly. Instead, you should read zconf.y, but you need to understand Bison grammer for that...