s3: Add "share_mode_stale_server"

This is a helper routine that prunes a dead share mode entry on demand. This
prepares for removing the serverids_exist call in parse_share_modes.

Signed-off-by: Jeremy Allison <jra@samba.org>

2 files changed, 33 insertions, 0 deletions

diff --git a/source3/locking/locking.c b/source3/locking/locking.c
index b9afd2392c..df21104028 100644
--- a/source3/locking/locking.c
+++ b/source3/locking/locking.c
@@ -625,6 +625,38 @@ bool is_deferred_open_entry(const struct share_mode_entry *e)
 	return (e->op_type == DEFERRED_OPEN_ENTRY);
 }
 
+/*
+ * In case d->share_modes[i] conflicts with something or otherwise is
+ * being used, we need to make sure the corresponding process still
+ * exists. This routine checks it and potentially removes the entry
+ * from d->share_modes. Modifies d->num_share_modes, watch out in
+ * routines iterating over that array.
+ */
+bool share_mode_stale_pid(struct share_mode_data *d, unsigned i)
+{
+	struct share_mode_entry *e;
+
+	if (i > d->num_share_modes) {
+		DEBUG(1, ("Asking for index %u, only %u around\n",
+			  i, (unsigned)d->num_share_modes));
+		return false;
+	}
+	e = &d->share_modes[i];
+	if (serverid_exists(&e->pid)) {
+		DEBUG(10, ("PID %s (index %u out of %u) still exists\n",
+			   procid_str_static(&e->pid), i,
+			   (unsigned)d->num_share_modes));
+		return false;
+	}
+	DEBUG(10, ("PID %s (index %u out of %u) does not exist anymore\n",
+		   procid_str_static(&e->pid), i,
+		   (unsigned)d->num_share_modes));
+	*e = d->share_modes[d->num_share_modes-1];
+	d->num_share_modes -= 1;
+	d->modified = true;
+	return true;
+}
+
 /*******************************************************************
  Fill a share mode entry.
 ********************************************************************/
diff --git a/source3/locking/proto.h b/source3/locking/proto.h
index 54badd9149..f6a6f2ee12 100644
--- a/source3/locking/proto.h
+++ b/source3/locking/proto.h
@@ -168,6 +168,7 @@ void get_file_infos(struct file_id id,
 		    struct timespec *write_time);
 bool is_valid_share_mode_entry(const struct share_mode_entry *e);
 bool is_deferred_open_entry(const struct share_mode_entry *e);
+bool share_mode_stale_pid(struct share_mode_data *d, unsigned i);
 void set_share_mode(struct share_mode_lock *lck, files_struct *fsp,
 		    uid_t uid, uint64_t mid, uint16 op_type);
 void add_deferred_open(struct share_mode_lock *lck, uint64_t mid,