From 24da58b43f922ab7aa378d864a83b10746076ac8 Mon Sep 17 00:00:00 2001
From: Olivier Matz <zer0@droids-corp.org>
Date: Thu, 7 Mar 2019 19:14:32 +0100
Subject: [PATCH] support exit callback registration

---
 include/ecoli_init.h | 18 +++++++++++++++++-
 src/ecoli_init.c     | 12 +++++++++++-
 test/test.c          |  2 ++
 3 files changed, 30 insertions(+), 2 deletions(-)

diff --git a/include/ecoli_init.h b/include/ecoli_init.h
index 4e8bc1e..80a0c01 100644
--- a/include/ecoli_init.h
+++ b/include/ecoli_init.h
@@ -14,6 +14,11 @@
 #include <ecoli_log.h>
 #include <ecoli_node.h>
 
+/**
+ * Register initialization and exit callbacks. These callbacks are
+ * ordered by priority: for initialization, the lowest priority is called
+ * first. For exit, the callbacks are invoked in reverse order.
+ */
 #define EC_INIT_REGISTER(t)						\
 	static void ec_init_init_##t(void);				\
 	static void __attribute__((constructor, used))			\
@@ -27,6 +32,11 @@
  */
 typedef int (ec_init_t)(void);
 
+/**
+ * Type of exit function.
+ */
+typedef void (ec_exit_t)(void);
+
 TAILQ_HEAD(ec_init_list, ec_init);
 
 /**
@@ -35,6 +45,7 @@ TAILQ_HEAD(ec_init_list, ec_init);
 struct ec_init {
 	TAILQ_ENTRY(ec_init) next;  /**< Next in list. */
 	ec_init_t *init;            /**< Init function. */
+	ec_exit_t *exit;            /**< Exit function. */
 	unsigned int priority;      /**< Priority (0=first, 99=last) */
 };
 
@@ -47,7 +58,7 @@ struct ec_init {
 void ec_init_register(struct ec_init *test);
 
 /**
- * Initialize ecoli library
+ * Initialize ecoli library.
  *
  * Must be called before any other function from libecoli, except
  * ec_malloc_register().
@@ -57,4 +68,9 @@ void ec_init_register(struct ec_init *test);
  */
 int ec_init(void);
 
+/**
+ * Uninitialize ecoli library.
+ */
+void ec_exit(void);
+
 #endif
diff --git a/src/ecoli_init.c b/src/ecoli_init.c
index fd5c0c3..a1c86e6 100644
--- a/src/ecoli_init.c
+++ b/src/ecoli_init.c
@@ -38,9 +38,19 @@ int ec_init(void)
 	struct ec_init *init;
 
 	TAILQ_FOREACH(init, &init_list, next) {
-		if (init->init() < 0)
+		if (init->init != NULL && init->init() < 0)
 			return -1;
 	}
 
 	return 0;
 }
+
+void ec_exit(void)
+{
+	struct ec_init *init;
+
+	TAILQ_FOREACH_REVERSE(init, &init_list, ec_init_list, next) {
+		if (init->exit != NULL)
+			init->exit();
+	}
+}
diff --git a/test/test.c b/test/test.c
index c874af9..d60adfc 100644
--- a/test/test.c
+++ b/test/test.c
@@ -390,6 +390,8 @@ int main(int argc, char **argv)
 			ret |= ec_test_one(argv[i]);
 	}
 
+	ec_exit();
+
 	leaks = debug_alloc_dump_leaks();
 
 	if (alloc_fail_proba == 0 && ret != 0) {
-- 
2.20.1