path: root/scripts/kconfig/zconf.l
diff options
authorMasahiro Yamada <yamada.masahiro@socionext.com>2018-05-28 18:21:49 +0900
committerMasahiro Yamada <yamada.masahiro@socionext.com>2018-05-29 03:31:19 +0900
commit9ced3bddec080e974e910bf887715540a8d9d96b (patch)
tree4bb735afdabb6e4b9dd6f2d607a596fde7b37301 /scripts/kconfig/zconf.l
parentkconfig: begin PARAM state only when seeing a command keyword (diff)
kconfig: support user-defined function and recursively expanded variable
Now, we got a basic ability to test compiler capability in Kconfig. config CC_HAS_STACKPROTECTOR def_bool $(shell,($(CC) -Werror -fstack-protector -E -x c /dev/null -o /dev/null 2>/dev/null) && echo y || echo n) This works, but it is ugly to repeat this long boilerplate. We want to describe like this: config CC_HAS_STACKPROTECTOR bool default $(cc-option,-fstack-protector) It is straight-forward to add a new function, but I do not like to hard-code specialized functions like that. Hence, here is another feature, user-defined function. This works as a textual shorthand with parameterization. A user-defined function is defined by using the = operator, and can be referenced in the same way as built-in functions. A user-defined function in Make is referenced like $(call my-func,arg1,arg2), but I omitted the 'call' to make the syntax shorter. The definition of a user-defined function contains $(1), $(2), etc. in its body to reference the parameters. It is grammatically valid to pass more or fewer arguments when calling it. We already exploit this feature in our makefiles; scripts/Kbuild.include defines cc-option which takes two arguments at most, but most of the callers pass only one argument. By the way, a variable is supported as a subset of this feature since a variable is "a user-defined function with zero argument". In this context, I mean "variable" as recursively expanded variable. I will add a different flavored variable in the next commit. The code above can be written as follows: [Example Code] success = $(shell,($(1)) >/dev/null 2>&1 && echo y || echo n) cc-option = $(success,$(CC) -Werror $(1) -E -x c /dev/null -o /dev/null) config CC_HAS_STACKPROTECTOR def_bool $(cc-option,-fstack-protector) [Result] $ make -s alldefconfig && tail -n 1 .config CONFIG_CC_HAS_STACKPROTECTOR=y Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Diffstat (limited to 'scripts/kconfig/zconf.l')
1 files changed, 15 insertions, 2 deletions
diff --git a/scripts/kconfig/zconf.l b/scripts/kconfig/zconf.l
index 9a147977dc3f..dd08f7a38ccd 100644
--- a/scripts/kconfig/zconf.l
+++ b/scripts/kconfig/zconf.l
@@ -1,12 +1,13 @@
%option nostdinit noyywrap never-interactive full ecs
%option 8bit nodefault yylineno
* Copyright (C) 2002 Roman Zippel <zippel@linux-m68k.org>
* Released under the terms of the GNU GPL v2.0.
+#include <assert.h>
#include <limits.h>
#include <stdio.h>
#include <stdlib.h>
@@ -111,8 +112,10 @@ n [A-Za-z0-9_-]
alloc_string(yytext, yyleng);
yylval.string = text;
- return T_WORD;
+ return T_VARIABLE;
+ "=" { BEGIN(ASSIGN_VAL); return T_ASSIGN; }
+ [[:blank:]]+
. warn_ignored_character(*yytext);
\n {
@@ -120,6 +123,16 @@ n [A-Za-z0-9_-]
+ [^[:blank:]\n]+.* {
+ alloc_string(yytext, yyleng);
+ yylval.string = text;
+ return T_ASSIGN_VAL;
+ }
+ \n { BEGIN(INITIAL); return T_EOL; }
+ .
"&&" return T_AND;
"||" return T_OR;