Prevent possible null pointer dereference

Neither of these functions should ever be called with dc == NULL.
But it's easy to prevent the potential crash.

Signed-off-by: Dirk Hohndel <dirk@hohndel.org>
This commit is contained in:
Dirk Hohndel 2015-06-21 21:38:12 -07:00
parent 52ee5f28c2
commit 18d52ec86e

17
dive.c
View file

@ -728,6 +728,8 @@ void per_cylinder_mean_depth(struct dive *dive, struct divecomputer *dc, int *me
for (i = 0; i < MAX_CYLINDERS; i++)
mean[i] = duration[i] = 0;
if (!dc)
return;
struct event *ev = get_next_event(dc->events, "gaschange");
if (!ev || (dc && dc->sample && ev->time.seconds == dc->sample[0].time.seconds && get_next_event(ev->next, "gaschange") == NULL)) {
// we have either no gas change or only one gas change and that's setting an explicit first cylinder
@ -861,13 +863,14 @@ static int same_rounded_pressure(pressure_t a, pressure_t b)
* first cylinder - in which case cylinder 0 is indeed the first cylinder */
int explicit_first_cylinder(struct dive *dive, struct divecomputer *dc)
{
struct event *ev = get_next_event(dc->events, "gaschange");
if (ev && dc && dc->sample && ev->time.seconds == dc->sample[0].time.seconds)
return get_cylinder_index(dive, ev);
else if (dc->divemode == CCR)
return MAX(get_cylinder_idx_by_use(dive, DILUENT), 0);
else
return 0;
if (dc) {
struct event *ev = get_next_event(dc->events, "gaschange");
if (ev && dc->sample && ev->time.seconds == dc->sample[0].time.seconds)
return get_cylinder_index(dive, ev);
else if (dc->divemode == CCR)
return MAX(get_cylinder_idx_by_use(dive, DILUENT), 0);
}
return 0;
}
/* this gets called when the dive mode has changed (so OC vs. CC)