From f75be76ee145f7fd838a9a866e9aecdf88e36ed3 Mon Sep 17 00:00:00 2001
From: Enno Rehling <enno.rehling@gmail.com>
Date: Sun, 11 Sep 2016 12:15:53 +0200
Subject: [PATCH] created a new configuration caching API (config_changed).
 applied this to some rules.

---
 src/kernel/config.c      | 24 ++++++++++++++++++++++--
 src/kernel/config.h      |  1 +
 src/kernel/config.test.c | 23 +++++++++++++++++++++++
 3 files changed, 46 insertions(+), 2 deletions(-)

diff --git a/src/kernel/config.c b/src/kernel/config.c
index 89d816f0f..481a68220 100644
--- a/src/kernel/config.c
+++ b/src/kernel/config.c
@@ -887,14 +887,23 @@ int rule_blessed_harvest(void)
 
 int rule_alliance_limit(void)
 {
-    int rule = config_get_int("rules.limit.alliance", 0);
+    static int cache_token;
+    static int rule = 0;
+
+    if (config_changed(&cache_token)) {
+        rule = config_get_int("rules.limit.alliance", 0);
+    }
     assert(rule >= 0);
     return rule;
 }
 
 int rule_faction_limit(void)
 {
-    int rule = config_get_int("rules.limit.faction", 0);
+    static int cache_token;
+    static int rule = 0;
+    if (config_changed(&cache_token)) {
+        rule = config_get_int("rules.limit.faction", 0);
+    }
     assert(rule >= 0);
     return rule;
 }
@@ -1053,8 +1062,19 @@ bool markets_module(void)
 }
 
 static struct param *configuration;
+static int config_cache_key = 1;
+
+bool config_changed(int *cache_key) {
+    assert(cache_key);
+    if (config_cache_key != *cache_key) {
+        *cache_key = config_cache_key;
+        return true;
+    }
+    return false;
+}
 
 void config_set(const char *key, const char *value) {
+    ++config_cache_key;
     set_param(&configuration, key, value);
 }
 
diff --git a/src/kernel/config.h b/src/kernel/config.h
index 081a96e61..8e0bd72e5 100644
--- a/src/kernel/config.h
+++ b/src/kernel/config.h
@@ -184,6 +184,7 @@ struct param;
     int config_get_int(const char *key, int def);
     double config_get_flt(const char *key, double def);
     bool config_token(const char *key, const char *tok);
+    bool config_changed(int *cache_key);
 
     char * join_path(const char *p1, const char *p2, char *dst, size_t len);
     bool ExpensiveMigrants(void);
diff --git a/src/kernel/config.test.c b/src/kernel/config.test.c
index 6bc193bbf..a5bad30c7 100644
--- a/src/kernel/config.test.c
+++ b/src/kernel/config.test.c
@@ -190,9 +190,31 @@ static void test_default_order(CuTest *tc) {
     test_cleanup();
 }
 
+static void test_config_cache(CuTest *tc) {
+    int key = 0;
+
+    test_setup();
+    CuAssertTrue(tc, config_changed(&key));
+    config_set("hodor", "0");
+    CuAssertTrue(tc, config_changed(&key));
+    CuAssertTrue(tc, !config_changed(&key));
+    test_cleanup();
+}
+
+static void test_rules(CuTest *tc) {
+    CuAssertIntEquals(tc, 0, rule_alliance_limit());
+    config_set("rules.limit.alliance", "1");
+    CuAssertIntEquals(tc, 1, rule_alliance_limit());
+
+    CuAssertIntEquals(tc, 0, rule_faction_limit());
+    config_set("rules.limit.faction", "1000");
+    CuAssertIntEquals(tc, 1000, rule_faction_limit());
+}
+
 CuSuite *get_config_suite(void)
 {
     CuSuite *suite = CuSuiteNew();
+    SUITE_ADD_TEST(suite, test_config_cache);
     SUITE_ADD_TEST(suite, test_get_set_param);
     SUITE_ADD_TEST(suite, test_param_int);
     SUITE_ADD_TEST(suite, test_param_flt);
@@ -200,5 +222,6 @@ CuSuite *get_config_suite(void)
     SUITE_ADD_TEST(suite, test_getunit);
     SUITE_ADD_TEST(suite, test_read_unitid);
     SUITE_ADD_TEST(suite, test_default_order);
+    SUITE_ADD_TEST(suite, test_rules);
     return suite;
 }