From: Masahiro Yamada <yamada.masahiro@socionext.com>
Date: Mon, 28 May 2018 09:21:53 +0000 (+0900)
Subject: kconfig: add 'info', 'warning-if', and 'error-if' built-in functions
X-Git-Url: https://jxself.org/git/?p=carl9170fw.git;a=commitdiff_plain;h=715ca322b4f23a2b15adb34d0d829ae34c04dede

kconfig: add 'info', 'warning-if', and 'error-if' built-in functions

Syntax:
  $(info,<text>)
  $(warning-if,<condition>,<text>)
  $(error-if,<condition>,<text)

The 'info' function prints a message to stdout as in Make.

The 'warning-if' and 'error-if' are similar to 'warning' and 'error'
in Make, but take the condition parameter.  They are effective only
when the <condition> part is y.

Kconfig does not implement the lazy expansion as used in the 'if'
'and, 'or' functions in Make.  In other words, Kconfig does not
support conditional expansion.  The unconditional 'error' function
would always terminate the parsing, hence would be useless in Kconfig.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Christian Lamparter <chunkeey@gmail.com>
---

diff --git a/config/preprocess.c b/config/preprocess.c
index 56aa1f0..5ee58ee 100644
--- a/config/preprocess.c
+++ b/config/preprocess.c
@@ -106,6 +106,21 @@ struct function {
 	char *(*func)(int argc, char *argv[]);
 };
 
+static char *do_error_if(int argc, char *argv[])
+{
+	if (!strcmp(argv[0], "y"))
+		pperror("%s", argv[1]);
+
+	return NULL;
+}
+
+static char *do_info(int argc, char *argv[])
+{
+	printf("%s\n", argv[0]);
+
+	return xstrdup("");
+}
+
 static char *do_shell(int argc, char *argv[])
 {
 	FILE *p;
@@ -146,9 +161,21 @@ static char *do_shell(int argc, char *argv[])
 	return xstrdup(buf);
 }
 
+static char *do_warning_if(int argc, char *argv[])
+{
+	if (!strcmp(argv[0], "y"))
+		fprintf(stderr, "%s:%d: %s\n",
+			current_file->name, yylineno, argv[1]);
+
+	return xstrdup("");
+}
+
 static const struct function function_table[] = {
 	/* Name		MIN	MAX	Function */
+	{ "error-if",	2,	2,	do_error_if },
+	{ "info",	1,	1,	do_info },
 	{ "shell",	1,	1,	do_shell },
+	{ "warning-if",	2,	2,	do_warning_if },
 };
 
 #define FUNCTION_MAX_ARGS		16