Re: [PATCH 08/30] kconfig: add built-in function support

From: Masahiro Yamada
Date: Sun Apr 15 2018 - 11:13:02 EST


2018-04-15 16:57 GMT+09:00 Ulf Magnusson <ulfalizer@xxxxxxxxx>:
> 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.


OK, will do.





--
Best Regards
Masahiro Yamada