On Sat, Aug 5, 2023 at 6:57 PM Yoann Congal <yoann.congal@xxxxxxxx> wrote: > > Exit on error when asking for value that has an invalid default value > and stdin has reached EOF. This happens in particular for hex/int > configs without an explicit default value. > > Previously, this case would loop: > * oldconfig prompts for the value but stdin has reached EOF > * It gets the global default value : an empty string > * This is not a valid hex/int value so it prompts again, hence the infinite loop. > > This case happens with a configuration like this (a hex config without a > valid default value): > config TEST_KCONFIG > hex "Test KConfig" > # default 0x0 > > And using: > make oldconfig < /dev/null > > This was discovered when working on Yocto bug[0] on a downstream > kconfig user (U-boot) > > [0]: https://bugzilla.yoctoproject.org/show_bug.cgi?id=14136 > > Signed-off-by: Yoann Congal <yoann.congal@xxxxxxxx> > --- > v1->v2: > * Improve coding style > * Put more info in the commit message > > scripts/kconfig/conf.c | 10 +++++++++- > 1 file changed, 9 insertions(+), 1 deletion(-) > > diff --git a/scripts/kconfig/conf.c b/scripts/kconfig/conf.c > index 7cf63261d951c..8f32cbbce4805 100644 > --- a/scripts/kconfig/conf.c > +++ b/scripts/kconfig/conf.c > @@ -377,8 +377,16 @@ static int conf_string(struct menu *menu) > line[strlen(line)-1] = 0; > def = line; > } > - if (def && sym_set_string_value(sym, def)) > + if (def && sym_set_string_value(sym, def)) { > return 0; > + } else { > + if (feof(stdin) && !sym_string_valid(sym, sym_get_string_value(sym))) { > + fprintf(stderr, > + "Symbol %s has invalid default value and stdin reached EOF\n", > + sym->name); > + exit(1); > + } > + } > } > } > > -- > 2.30.2 > It is strange (and consistent) to bail out only for particular types. I would change the code simply as follows: --- a/scripts/kconfig/conf.c +++ b/scripts/kconfig/conf.c @@ -76,8 +76,10 @@ static void strip(char *str) /* Helper function to facilitate fgets() by Jean Sacren. */ static void xfgets(char *str, int size, FILE *in) { - if (!fgets(str, size, in)) + if (!fgets(str, size, in)) { fprintf(stderr, "\nError in reading or end of file.\n"); + exit(1); + } if (!tty_stdio) printf("%s", str); yes "" | make config will succeed. make config < /dev/null will fail. People expecting the closed stdin to succeed may start complaining, but I believe they must fix their wrong scripts. -- Best Regards Masahiro Yamada
