From 744511ffe254e98044ac46e10938724c2f6c6b5f Mon Sep 17 00:00:00 2001
From: Moritz Grimm <mgrimm@mrsserver.net>
Date: Tue, 9 Jun 2015 23:02:45 +0200
Subject: [PATCH] Expose "configuration stashing" API

---
 src/cfg.c         | 35 +++++++++++++++++++++++++++++------
 src/cfg.h         |  4 ++++
 src/cfg_private.h |  1 +
 tests/check_cfg.c | 20 ++++++++++++++++++++
 4 files changed, 54 insertions(+), 6 deletions(-)

diff --git a/src/cfg.c b/src/cfg.c
index 91d0128..acc302e 100644
--- a/src/cfg.c
+++ b/src/cfg.c
@@ -63,6 +63,8 @@ _cfg_reset(struct cfg *c)
 static void
 _cfg_copy(struct cfg *dst, struct cfg *src)
 {
+	dst->_master_cfg = src->_master_cfg;
+
 	memcpy(&dst->program, &src->program, sizeof(dst->program));
 
 	memcpy(&dst->server, &src->server, sizeof(dst->server));
@@ -121,6 +123,7 @@ int
 cfg_init(void)
 {
 	_cfg_reset(&cfg);
+	cfg._master_cfg = 1;
 	return (0);
 }
 
@@ -130,18 +133,38 @@ cfg_exit(void)
 	_cfg_reset(&cfg);
 }
 
+void
+cfg_save(void)
+{
+	_cfg_reset(&cfg_tmp);
+	_cfg_copy(&cfg_tmp, &cfg);
+}
+
+void
+cfg_pop(void)
+{
+	if (!cfg_tmp._master_cfg)
+		return;
+	_cfg_reset(&cfg);
+	_cfg_copy(&cfg, &cfg_tmp);
+	_cfg_reset(&cfg_tmp);
+}
+
+void
+cfg_clear(void)
+{
+	_cfg_reset(&cfg_tmp);
+}
+
 int
 cfg_reload(void)
 {
-	_cfg_copy(&cfg_tmp, &cfg);
+	cfg_save();
 	if (0 > _cfg_load()) {
-		/* roll back */
-		_cfg_reset(&cfg);
-		_cfg_copy(&cfg, &cfg_tmp);
-		_cfg_reset(&cfg_tmp);
+		cfg_pop();
 		return (-1);
 	}
-	_cfg_reset(&cfg_tmp);
+	cfg_clear();
 
 	return (0);
 }
diff --git a/src/cfg.h b/src/cfg.h
index 8c03ca2..57795a1 100644
--- a/src/cfg.h
+++ b/src/cfg.h
@@ -65,6 +65,10 @@ enum cfg_stream_format {
 int	cfg_init(void);
 void	cfg_exit(void);
 
+void	cfg_save(void);
+void	cfg_pop(void);
+void	cfg_clear(void);
+
 int	cfg_reload(void);
 
 int	cfg_stream_str2fmt(const char *, enum cfg_stream_format *);
diff --git a/src/cfg_private.h b/src/cfg_private.h
index 31b759f..eb1dd2a 100644
--- a/src/cfg_private.h
+++ b/src/cfg_private.h
@@ -31,6 +31,7 @@
 #define DEFAULT_USER		"source"
 
 struct cfg {
+	int				 _master_cfg;
 	struct program {
 		char			 name[PATH_MAX];
 		enum cfg_config_type	 config_type;
diff --git a/tests/check_cfg.c b/tests/check_cfg.c
index b5dfd76..d4abc57 100644
--- a/tests/check_cfg.c
+++ b/tests/check_cfg.c
@@ -100,6 +100,25 @@ Suite * cfg_suite(void);
 void	setup_checked(void);
 void	teardown_checked(void);
 
+START_TEST(test_stash)
+{
+	ck_assert_ptr_eq(cfg_get_stream_name(), NULL);
+	ck_assert_int_eq(cfg_set_stream_name("test_stash", NULL), 0);
+	ck_assert_str_eq(cfg_get_stream_name(), "test_stash");
+	cfg_save();
+	ck_assert_int_eq(cfg_set_stream_name("test_stash2", NULL), 0);
+	ck_assert_str_eq(cfg_get_stream_name(), "test_stash2");
+	cfg_pop();
+	ck_assert_str_eq(cfg_get_stream_name(), "test_stash");
+	cfg_pop();
+	ck_assert_str_eq(cfg_get_stream_name(), "test_stash");
+	cfg_save();
+	cfg_clear();
+	cfg_pop();
+	ck_assert_str_eq(cfg_get_stream_name(), "test_stash");
+}
+END_TEST
+
 START_TEST(test_stream_str2fmt)
 {
 	enum cfg_stream_format	fmt;
@@ -729,6 +748,7 @@ cfg_suite(void)
 
 	tc_core = tcase_create("Core");
 	tcase_add_checked_fixture(tc_core, setup_checked, teardown_checked);
+	tcase_add_test(tc_core, test_stash);
 	tcase_add_test(tc_core, test_stream_str2fmt);
 	tcase_add_test(tc_core, test_stream_fmt2str);
 	tcase_add_test(tc_core, test_file_check);