kconfig: fix infinite loop when expanding a macro at the end of file

A macro placed at the end of a file with no newline causes an infinite
loop.

[Test Kconfig]
  $(info,hello)
  \ No newline at end of file

I realized that flex-provided input() returns 0 instead of EOF when it
reaches the end of a file.

Fixes: 104daea149 ("kconfig: reference environment variables directly and remove 'option env='")
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
This commit is contained in:
Masahiro Yamada 2024-02-03 00:57:59 +09:00
parent fee9b6d14a
commit af8bbce920

View File

@ -303,8 +303,11 @@ static char *expand_token(const char *in, size_t n)
new_string();
append_string(in, n);
/* get the whole line because we do not know the end of token. */
while ((c = input()) != EOF) {
/*
* get the whole line because we do not know the end of token.
* input() returns 0 (not EOF!) when it reachs the end of file.
*/
while ((c = input()) != 0) {
if (c == '\n') {
unput(c);
break;