libps (_proc_stat_free): Fix memory leak

The thread_waits field was never freed; this change adds the code to do
so if the corresponding flag is set.

Users are also warned of the consequences, namely, that they should not
free process proc_stats before all their associated thread ones are
gone, since the latter may reference the former's thread_waits field.
However, with the normal interface (ie.  ps_context_free), all
proc_stats are freed at once, so this is not an issue.

* libps/procstat.c (_proc_stat_free): Free ps->thread_waits if
PSTAT_THREAD_WAITS flag is set.
* libps/ps.h (_proc_stat_free): Document that thread proc_stats must be
freed before process proc_stat can be.

1 files changed, 2 insertions, 0 deletions

diff --git a/libps/procstat.c b/libps/procstat.c
index 33a01cc1..0717065c 100644
--- a/libps/procstat.c
+++ b/libps/procstat.c
@@ -1058,6 +1058,8 @@ _proc_stat_free (ps)
   MFREEMEM (PSTAT_ENV, env, ps->env_len, ps->env_vm_alloced, 0, char);
   MFREEMEM (PSTAT_TASK_EVENTS, task_events_info, ps->task_events_info_size,
 	    0, &ps->task_events_info_buf, char);
+  MFREEMEM (PSTAT_THREAD_WAITS, thread_waits, ps->thread_waits_len,
+	    ps->thread_waits_vm_alloced, 0, char);
 
   FREE (ps);
 }