kconfig: Introduce IS_ENABLED(), IS_BUILTIN() and IS_MODULE()

Replace the config_is_*() macros with a variant that allows for grepping
for usage of CONFIG_* options in the code. Usage:

  if (IS_ENABLED(CONFIG_NUMA))

or

  #if IS_ENABLED(CONFIG_NUMA)

The IS_ENABLED() macro evaluates to 1 if the argument is set (to either 'y'
or 'm'), IS_BUILTIN() tests if the option is 'y' and IS_MODULE() test if
the option is 'm'. Only boolean and tristate options are supported.

Reviewed-by: Arnaud Lacombe <lacombar@gmail.com>
Acked-by: Randy Dunlap <rdunlap@xenotime.net>
Signed-off-by: Michal Marek <mmarek@suse.cz>

diff --git a/Makefile b/Makefile
index afb8e0d26f2c6134828d5d63e557799e8ef6e199..bd7629bb93da4982e981ee21754f6eb889727c45 100644 (file)
--- a/Makefile
+++ b/Makefile
@@ -360,7 +360,7 @@ CFLAGS_GCOV = -fprofile-arcs -ftest-coverage
 LINUXINCLUDE    := -I$(srctree)/arch/$(hdr-arch)/include \
                    -Iarch/$(hdr-arch)/include/generated -Iinclude \
                    $(if $(KBUILD_SRC), -I$(srctree)/include) \
-                   -include include/generated/autoconf.h
+                   -include $(srctree)/include/linux/kconfig.h
 
 KBUILD_CPPFLAGS := -D__KERNEL__
 

diff --git a/include/linux/kconfig.h b/include/linux/kconfig.h
new file mode 100644 (file)
index 0000000..067eda0
--- /dev/null
+++ b/include/linux/kconfig.h
@@ -0,0 +1,32 @@
+#ifndef __LINUX_KCONFIG_H
+#define __LINUX_KCONFIG_H
+
+#include <generated/autoconf.h>
+
+/*
+ * Helper macros to use CONFIG_ options in C expressions. Note that
+ * these only work with boolean and tristate options.
+ */
+
+/*
+ * IS_ENABLED(CONFIG_FOO) evaluates to 1 if CONFIG_FOO is set to 'y' or 'm',
+ * 0 otherwise.
+ *
+ */
+#define IS_ENABLED(option) \
+       (__enabled_ ## option || __enabled_ ## option ## _MODULE)
+
+/*
+ * IS_BUILTIN(CONFIG_FOO) evaluates to 1 if CONFIG_FOO is set to 'y', 0
+ * otherwise. For boolean options, this is equivalent to
+ * IS_ENABLED(CONFIG_FOO).
+ */
+#define IS_BUILTIN(option) __enabled_ ## option
+
+/*
+ * IS_MODULE(CONFIG_FOO) evaluates to 1 if CONFIG_FOO is set to 'm', 0
+ * otherwise.
+ */
+#define IS_MODULE(option) __enabled_ ## option ## _MODULE
+
+#endif /* __LINUX_KCONFIG_H */

diff --git a/scripts/kconfig/confdata.c b/scripts/kconfig/confdata.c
index df629ecb4fdff1830e7f078b43d4b34d9ef5f450..59b667cae5f33e4437e1beaa6bdfcdcb93bc8fcb 100644 (file)
--- a/scripts/kconfig/confdata.c
+++ b/scripts/kconfig/confdata.c
@@ -495,15 +495,25 @@ header_print_symbol(FILE *fp, struct symbol *sym, const char *value, void *arg)
 
                switch (*value) {
                case 'n':
-                       return;
+                       break;
                case 'm':
                        suffix = "_MODULE";
                        /* fall through */
                default:
-                       value = "1";
+                       fprintf(fp, "#define %s%s%s 1\n",
+                           CONFIG_, sym->name, suffix);
                }
-               fprintf(fp, "#define %s%s%s %s\n",
-                   CONFIG_, sym->name, suffix, value);
+               /*
+                * Generate the __enabled_CONFIG_* and
+                * __enabled_CONFIG_*_MODULE macros for use by the
+                * IS_{ENABLED,BUILTIN,MODULE} macros. The _MODULE variant is
+                * generated even for booleans so that the IS_ENABLED() macro
+                * works.
+                */
+               fprintf(fp, "#define __enabled_" CONFIG_ "%s %d\n",
+                               sym->name, (*value == 'y'));
+               fprintf(fp, "#define __enabled_" CONFIG_ "%s_MODULE %d\n",
+                               sym->name, (*value == 'm'));
                break;
        }
        case S_HEX: {
@@ -554,58 +564,6 @@ static struct conf_printer header_printer_cb =
        .print_comment = header_print_comment,
 };
 
-/*
- * Function-style header printer
- *
- * This printer is used to generate the config_is_xxx() function-style macros
- * in `include/generated/autoconf.h' 
- */
-static void
-header_function_print_symbol(FILE *fp, struct symbol *sym, const char *value, void *arg)
-{
-       int val = 0;
-       char c;
-       char *tmp, *d;
-
-       switch (sym->type) {
-       case S_BOOLEAN:
-       case S_TRISTATE:
-               break;
-       default:
-               return;
-       }
-       if (*value == 'm')
-               val = 2;
-       else if (*value == 'y')
-               val = 1;
-
-       d = strdup(CONFIG_);
-       tmp = d;
-       while ((c = *d)) {
-               *d = tolower(c);
-               d++;
-       }
-
-       fprintf(fp, "#define %sis_", tmp);
-       free(tmp);
-
-       d = strdup(sym->name);
-       tmp = d;
-       while ((c = *d)) {
-               *d = tolower(c);
-               d++;
-       }
-       fprintf(fp, "%s%s() %d\n", tmp, (val > 1) ? "_module" : "",
-                     val ? 1 : 0);
-       free(tmp);
-}
-
-static struct conf_printer header_function_printer_cb =
-{
-       .print_symbol = header_function_print_symbol,
-};
-
-
 /*
  * Tristate printer
  *
@@ -997,7 +955,6 @@ int conf_write_autoconf(void)
                conf_write_symbol(tristate, sym, &tristate_printer_cb, (void *)1);
 
                conf_write_symbol(out_h, sym, &header_printer_cb, NULL);
-               conf_write_symbol(out_h, sym, &header_function_printer_cb, NULL);
        }
        fclose(out);
        fclose(tristate);