On Fri, Apr 13, 2018 at 7:06 AM, Masahiro Yamada <yamada.masahiro@xxxxxxxxxxxxx> wrote: > This commit adds a new concept 'function' to do more text processing > in Kconfig. > > A function call looks like this: > > $(function arg1, arg2, arg3, ...) > > This commit adds the basic infrastructure to expand functions. > Change the text expansion helpers to take arguments. > > Signed-off-by: Masahiro Yamada <yamada.masahiro@xxxxxxxxxxxxx> > --- > > Changes in v3: > - Split base infrastructure and 'shell' function > into separate patches. > > Changes in v2: > - Use 'shell' for getting stdout from the comment. > It was 'shell-stdout' in the previous version. > - Symplify the implementation since the expansion has been moved to > lexer. > > scripts/kconfig/preprocess.c | 142 +++++++++++++++++++++++++++++++++++++++---- > 1 file changed, 130 insertions(+), 12 deletions(-) > > diff --git a/scripts/kconfig/preprocess.c b/scripts/kconfig/preprocess.c > index fa4abc8..e77cf7c 100644 > --- a/scripts/kconfig/preprocess.c > +++ b/scripts/kconfig/preprocess.c > @@ -8,6 +8,10 @@ > > #include "list.h" > > +#define ARRAY_SIZE(arr) (sizeof(arr) / sizeof((arr)[0])) > + > +static char *expand_string_with_args(const char *in, int argc, char *argv[]); > + > /* > * Environment variables > */ > @@ -74,9 +78,47 @@ void env_write_dep(FILE *f, const char *autoconfig_name) > } > } > > -static char *eval_clause(const char *in) > +/* > + * Built-in Functions > + */ > +struct function { > + char *name; > + char *(*func)(int argc, char *argv[]); > +}; > + > +static const struct function function_table[] = { > +}; > + > +static char *function_call(const char *name, int argc, char *argv[]) > { > - char *res, *name; > + const struct function *f; > + int i; > + > + for (i = 0; i < ARRAY_SIZE(function_table); i++) { > + f = &function_table[i]; > + if (!strcmp(f->name, name)) > + return f->func(argc, argv); > + } > + > + return NULL; > +} > + > +#define FUNCTION_MAX_ARGS 16 > + > +/* > + * Evaluate a clause with arguments. argc/argv are arguments from the upper > + * function call. > + * > + * Returned string must be freed when done > + */ > +static char *eval_clause(const char *in, int argc, char *argv[]) > +{ > + char *tmp, *prev, *p, *res, *name; > + char delim = ' '; > + int new_argc = 0; > + char *new_argv[FUNCTION_MAX_ARGS]; > + int nest = 0; > + int i; > > /* > * Returns an empty string because '$()' should be evaluated > @@ -85,10 +127,73 @@ static char *eval_clause(const char *in) > if (!*in) > return xstrdup(""); > > - name = expand_string(in); > + tmp = xstrdup(in); > + > + prev = p = tmp; > > - res = env_expand(name); > + /* > + * Split into tokens > + * The function name and the first argument are separated by a space. > + * Arguments are separated by a comma. > + * For example, if the function call is like this: > + * $(foo abc,$(x),$(y)) > + * > + * The input string for this helper should be: > + * foo abc,$(x),$(y) > + * > + * and split into: > + * new_argv[0]: foo > + * new_argv[1]: abc > + * new_argv[2]: $(x) > + * new_argv[3]: $(y) > + */ > + while (*p) { > + if (nest == 0 && *p == delim) { > + *p = 0; > + new_argv[new_argc++] = prev; Erroring out would be nicer than overflowing the array. Cheers, Ulf -- To unsubscribe from this list: send the line "unsubscribe linux-kbuild" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html