The compiler has two sets of complaints. Firstly, `t->tm_gmtoffset` is
a `long int`, but it is being passed to `abs`, which leads to warnings
such as:
ulogd_output_JSON.c:308:34: warning: absolute value function `abs` given an argument of type `long int` but has parameter of type `int` which may cause truncation of value
Secondly, it can't verify that the hour value derived from the offset
will in fact fit into `%02d`, thus:
ulogd_output_JSON.c:306:37: warning: `%02d` directive output may be truncated writing between 2 and 6 bytes into a region of size 5
To remedy these, we now mod the offset by 86,400 and assign it to an `int`
before deriving the hour and minute values.
We also change the format-specifier for the hour value to `%+03d` which
causes a sign to be printed even if the value is positive, thus allowing
us not to specify the sign explicitly and to drop the `abs` call for the
hour value.
Signed-off-by: Jeremy Sowden <jeremy@xxxxxxxxxx>
---
output/ulogd_output_JSON.c | 9 +++++----
1 file changed, 5 insertions(+), 4 deletions(-)
diff --git a/output/ulogd_output_JSON.c b/output/ulogd_output_JSON.c
index 6edfa902efaf..f5c065dd062a 100644
--- a/output/ulogd_output_JSON.c
+++ b/output/ulogd_output_JSON.c
@@ -302,11 +302,12 @@ static int json_interp(struct ulogd_pluginstance *upi)
now = time(NULL);
t = localtime_r(&now, &result);
if (unlikely(*opi->cached_tz = '\0' || t->tm_gmtoff != opi->cached_gmtoff)) {
+ int gmtoff = t->tm_gmtoff % 86400;
+ int gmtoff_h = gmtoff / 3600;
+ int gmtoff_m = abs(gmtoff) / 60 % 60;
+
snprintf(opi->cached_tz, sizeof(opi->cached_tz),
- "%c%02d%02d",
- t->tm_gmtoff > 0 ? '+' : '-',
- abs(t->tm_gmtoff) / 60 / 60,
- abs(t->tm_gmtoff) / 60 % 60);
+ "%+03d%02d", gmtoff_h, gmtoff_m);
}
if (pp_is_valid(inp, opi->usec_idx)) {
--
2.33.0
