On Mon, Mar 02, 2026 at 10:18:12AM +0000, david.laight.linux@gmail.com wrote:
> From: David Laight <david.laight.linux@gmail.com>
>
> Output the characters before or after the pad - writing the pad takes more code.
>
> Include additional/changed tests
>
> Signed-off-by: David Laight <david.laight.linux@gmail.com>
Acked-by: Willy Tarreau <w@1wt.eu>
Willy
> ---
>
> Unchanged for v4.
>
> Changes for v3:
> - Formally part of patch 7.
>
> tools/include/nolibc/stdio.h | 6 +++++-
> tools/testing/selftests/nolibc/nolibc-test.c | 4 +++-
> 2 files changed, 8 insertions(+), 2 deletions(-)
>
> diff --git a/tools/include/nolibc/stdio.h b/tools/include/nolibc/stdio.h
> index ef8e7069d5cf..695676b44151 100644
> --- a/tools/include/nolibc/stdio.h
> +++ b/tools/include/nolibc/stdio.h
> @@ -544,7 +544,11 @@ int __nolibc_printf(__nolibc_printf_cb cb, void *state, const char *fmt, va_list
> /* Stop gcc back-merging this code into one of the conditionals above. */
> _NOLIBC_OPTIMIZER_HIDE_VAR(len);
>
> + /* Output the characters on the required side of any padding. */
> width -= len;
> + flags = _NOLIBC_PF_FLAGS_CONTAIN(flags, '-');
> + if (flags && cb(state, outstr, len) != 0)
> + return -1;
> while (width > 0) {
> /* Output pad in 16 byte blocks with the small block first. */
> int pad_len = ((width - 1) & 15) + 1;
> @@ -553,7 +557,7 @@ int __nolibc_printf(__nolibc_printf_cb cb, void *state, const char *fmt, va_list
> if (cb(state, " ", pad_len) != 0)
> return -1;
> }
> - if (cb(state, outstr, len) != 0)
> + if (!flags && cb(state, outstr, len) != 0)
> return -1;
> }
>
> diff --git a/tools/testing/selftests/nolibc/nolibc-test.c b/tools/testing/selftests/nolibc/nolibc-test.c
> index 4267c69ec37c..89ded1dd7318 100644
> --- a/tools/testing/selftests/nolibc/nolibc-test.c
> +++ b/tools/testing/selftests/nolibc/nolibc-test.c
> @@ -1845,9 +1845,11 @@ static int run_printf(int min, int max)
> CASE_TEST(truncation); EXPECT_VFPRINTF(1, "0123456789012345678901234", "%s", "0123456789012345678901234"); break;
> CASE_TEST(string_width); EXPECT_VFPRINTF(1, " 1", "%10s", "1"); break;
> CASE_TEST(number_width); EXPECT_VFPRINTF(1, " 1", "%10d", 1); break;
> + CASE_TEST(number_left); EXPECT_VFPRINTF(1, "|-5 |", "|%-8d|", -5); break;
> + CASE_TEST(string_align); EXPECT_VFPRINTF(1, "|foo |", "|%-8s|", "foo"); break;
> CASE_TEST(width_trunc); EXPECT_VFPRINTF(1, " 1", "%25d", 1); break;
> CASE_TEST(errno); errno = 22; EXPECT_VFPRINTF(is_nolibc, "errno=22", "%m"); break;
> - CASE_TEST(errno-neg); errno = -22; EXPECT_VFPRINTF(is_nolibc, " errno=-22", "%12m"); break;
> + CASE_TEST(errno-neg); errno = -22; EXPECT_VFPRINTF(is_nolibc, "errno=-22 ", "%-12m"); break;
> CASE_TEST(scanf); EXPECT_ZR(1, test_scanf()); break;
> CASE_TEST(printf_error); EXPECT_ZR(1, test_printf_error()); break;
> case __LINE__:
> --
> 2.39.5