s3-lib Add a way to allocate the task_id value in server_id

This safely allocates the task_id so that when we have multiple event
contexts, they can each have their own messaging context, particularly
for the imessaging subsystem under source4.

Andrew Bartlett

1 files changed, 42 insertions, 0 deletions

diff --git a/source3/lib/util.c b/source3/lib/util.c
index e43cfbbcb8..7913ce9ee7 100644
--- a/source3/lib/util.c
+++ b/source3/lib/util.c
@@ -2016,6 +2016,48 @@ struct server_id procid_self(void)
 	return pid_to_procid(getpid());
 }
 
+static struct idr_context *task_id_tree;
+
+static int free_task_id(struct server_id *server_id)
+{
+	idr_remove(task_id_tree, server_id->task_id);
+	return 0;
+}
+
+/* Return a server_id with a unique task_id element.  Free the
+ * returned pointer to de-allocate the task_id via a talloc destructor
+ * (ie, use talloc_free()) */
+struct server_id *new_server_id_task(TALLOC_CTX *mem_ctx)
+{
+	struct server_id *server_id;
+	int task_id;
+	if (!task_id_tree) {
+		task_id_tree = idr_init(NULL);
+		if (!task_id_tree) {
+			return NULL;
+		}
+	}
+
+	server_id = talloc(mem_ctx, struct server_id);
+
+	if (!server_id) {
+		return NULL;
+	}
+	*server_id = procid_self();
+
+	/* 0 is the default server_id, so we need to start with 1 */
+	task_id = idr_get_new_above(task_id_tree, server_id, 1, INT32_MAX);
+
+	if (task_id == -1) {
+		talloc_free(server_id);
+		return NULL;
+	}
+
+	talloc_set_destructor(server_id, free_task_id);
+	server_id->task_id = task_id;
+	return server_id;
+}
+
 bool procid_equal(const struct server_id *p1, const struct server_id *p2)
 {
 	if (p1->pid != p2->pid)