[PATCH v2 nolibc 19/53] selftests/nolibc: reduce syscalls during space padding

From: Paul E. McKenney
Date: Mon Jun 12 2023 - 16:51:24 EST


From: Thomas Weißschuh <linux@xxxxxxxxxxxxxx>

Previously each space character used for alignment during test execution
was written in a single write() call.
This would make the output from strace fairly unreadable.
Coalesce all spaces into a single call to write().

Signed-off-by: Thomas Weißschuh <linux@xxxxxxxxxxxxxx>
Signed-off-by: Willy Tarreau <w@xxxxxx>
Signed-off-by: Paul E. McKenney <paulmck@xxxxxxxxxx>
---
tools/testing/selftests/nolibc/nolibc-test.c | 15 +++++++++++----
1 file changed, 11 insertions(+), 4 deletions(-)

diff --git a/tools/testing/selftests/nolibc/nolibc-test.c b/tools/testing/selftests/nolibc/nolibc-test.c
index 0e2ee513b273..d5d4dea63cd6 100644
--- a/tools/testing/selftests/nolibc/nolibc-test.c
+++ b/tools/testing/selftests/nolibc/nolibc-test.c
@@ -111,19 +111,26 @@ const char *errorname(int err)
}
}

+static void putcharn(char c, size_t n)
+{
+ char buf[64];
+
+ memset(buf, c, n);
+ buf[n] = '\0';
+ fputs(buf, stdout);
+}
+
static int pad_spc(int llen, int cnt, const char *fmt, ...)
{
va_list args;
- int len;
int ret;

- for (len = 0; len < cnt - llen; len++)
- putchar(' ');
+ putcharn(' ', cnt - llen);

va_start(args, fmt);
ret = vfprintf(stdout, fmt, args);
va_end(args);
- return ret < 0 ? ret : ret + len;
+ return ret < 0 ? ret : ret + cnt - llen;
}

/* The tests below are intended to be used by the macroes, which evaluate
--
2.40.1