MT#62053 generalise config loading

Switch from specialised handling of config sections (used to load
signalling templates) to a more general approach using a callback
mechanism. This allows us to add more information to the config file
while keeping the details of the underlying GKeyFile hidden. Use a typed
hash table for type safety.

Change-Id: I71ddfda0202b47df363bcc5acf1725078774f8f1

daemon/call_interfaces.c

@@ -4188,14 +4188,14 @@ void call_interfaces_free(void) {
 	t_hash_table_destroy(rtpe_signalling_templates);
 }
 
-static void parse_templates(GHashTable *templates) {
+static void parse_templates(charp_ht templates) {
-	if (!templates)
+	if (!t_hash_table_is_set(templates))
 		return;
 
-	GHashTableIter iter;
+	charp_ht_iter iter;
-	g_hash_table_iter_init(&iter, templates);
+	t_hash_table_iter_init(&iter, templates);
-	void *keyp, *valuep;
+	char *keyp, *valuep;
-	while (g_hash_table_iter_next(&iter, &keyp, &valuep)) {
+	while (t_hash_table_iter_next(&iter, &keyp, &valuep)) {
 		char *key = keyp;
 		char *value = valuep;
 		t_hash_table_insert(rtpe_signalling_templates, str_dup(STR_PTR(key)), str_dup(STR_PTR(value)));
@@ -4215,7 +4215,7 @@ static void parse_templates(GHashTable *templates) {
 		rtpe_default_signalling_templates[OP_OTHER] = *tmpl;
 }
 
-int call_interfaces_init(GHashTable *templates) {
+int call_interfaces_init(charp_ht templates) {
 	int errcode;
 	PCRE2_SIZE erroff;
 

daemon/main.c

@@ -492,7 +492,7 @@ static void release_listeners(GQueue *q) {
 }
 
 
-static void options(int *argc, char ***argv, GHashTable *templates) {
+static void options(int *argc, char ***argv, charp_ht templates) {
 	g_autoptr(char_p) if_a = NULL;
 	g_autoptr(char_p) ks_a = NULL;
 	long int_keyspace_db;
@@ -730,7 +730,17 @@ static void options(int *argc, char ***argv, GHashTable *templates) {
 
 	config_load_ext(argc, argv, e, " - next-generation media proxy",
 			"/etc/rtpengine/rtpengine.conf", "rtpengine", &rtpe_config.common,
-			&templates_section, templates);
+			(struct rtpenging_config_callback []) {
+				{
+					.type = RCC_SECTION_KEYS,
+					.arg.ht = templates,
+					.section_keys = {
+						.name = &templates_section,
+						.callback = add_c_str_to_ht,
+					},
+				},
+				{ 0 },
+			});
 
 	// default values, if not configured
 	if (rtpe_config.rec_method == NULL)
@@ -1319,7 +1329,7 @@ fallback:
 }
 
 
-static void init_everything(GHashTable *templates) {
+static void init_everything(charp_ht templates) {
 	bufferpool_init();
 	gettimeofday(&rtpe_now, NULL);
 	log_init(rtpe_common_config_ptr->log_name);
@@ -1585,7 +1595,7 @@ static void uring_poller_loop(void *ptr) {
 int main(int argc, char **argv) {
 	early_init();
 	{
-		g_autoptr(GHashTable) templates = g_hash_table_new_full(g_str_hash, g_str_equal, g_free, g_free);
+		g_auto(charp_ht) templates = charp_ht_new();
 		options(&argc, &argv, templates);
 		init_everything(templates);
 	}

include/call_interfaces.h

@@ -323,7 +323,7 @@ void call_unlock_release(call_t *c);
 G_DEFINE_AUTO_CLEANUP_CLEAR_FUNC(sdp_ng_flags, call_ng_free_flags)
 G_DEFINE_AUTOPTR_CLEANUP_FUNC(call_t, call_unlock_release)
 
-int call_interfaces_init(GHashTable *);
+int call_interfaces_init(charp_ht);
 void call_interfaces_free(void);
 void call_interfaces_timer(void);
 

lib/auxlib.c

@@ -155,20 +155,26 @@ void config_load_free(struct rtpengine_common_config *cconfig) {
 	g_free(cconfig->pidfile);
 }
 
-static void load_templates(GKeyFile *kf, const char *template_section, GHashTable *templates) {
+static void section_keys_callback(GKeyFile *kf,
-	size_t length;
+		const char *section_name,
+		void (*callback)(const char *key, char *value, union rtpenging_config_callback_arg),
+		union rtpenging_config_callback_arg arg)
+{
+	if (!section_name)
+		return;
+
 	g_autoptr(GError) err = NULL;
-	g_autoptr(char_p) keys = g_key_file_get_keys(kf, template_section, &length, &err);
+	g_autoptr(char_p) keys = g_key_file_get_keys(kf, section_name, NULL, &err);
 	if (err)
-		die("Failed to load templates from given config file section '%s': %s", template_section, err->message);
+		die("Failed to load keys from given config file section '%s': %s", section_name, err->message);
 	if (!keys)
 		return; // empty config section
 
 	for (char **key = keys; *key; key++) {
-		char *val = g_key_file_get_string(kf, template_section, *key, &err);
+		char *val = g_key_file_get_string(kf, section_name, *key, &err);
 		if (err)
-			die("Failed to read template value '%s' from config file: %s", *key, err->message);
+			die("Failed to read config value '%s' (section '%s') from config file: %s", *key, section_name, err->message);
-		g_hash_table_insert(templates, g_strdup(*key), val); // hash table takes ownership of both
+		callback(*key, val, arg);
 	}
 }
 
@@ -179,7 +185,7 @@ G_DEFINE_AUTOPTR_CLEANUP_FUNC(char_p_shallow, g_free)
 void config_load_ext(int *argc, char ***argv, GOptionEntry *app_entries, const char *description,
 		char *default_config, char *default_section,
 		struct rtpengine_common_config *cconfig,
-		char * const *template_section, GHashTable *templates)
+		const struct rtpenging_config_callback *callbacks)
 {
 	g_autoptr(GOptionContext) c = NULL;
 	g_autoptr(GError) er = NULL;
@@ -380,8 +386,17 @@ void config_load_ext(int *argc, char ***argv, GOptionEntry *app_entries, const c
 		}
 	}
 
-	if (template_section && *template_section && templates)
+	for (const struct rtpenging_config_callback *cb = callbacks; cb; cb++) {
-		load_templates(kf, *template_section, templates);
+		switch (cb->type) {
+			case RCC_END:
+				break;
+
+			case RCC_SECTION_KEYS:
+				section_keys_callback(kf, *cb->section_keys.name, cb->section_keys.callback, cb->arg);
+				continue;
+		}
+		break;
+	}
 
 out:
 	// default common values, if not configured

lib/auxlib.h

@@ -49,6 +49,30 @@ struct rtpengine_common_config {
 
 extern struct rtpengine_common_config *rtpe_common_config_ptr;
 
+INLINE unsigned int c_str_hash(const char *s);
+INLINE gboolean c_str_equal(const char *a, const char *b);
+
+TYPED_GHASHTABLE(charp_ht, char, char, c_str_hash, c_str_equal, g_free, g_free)
+
+union rtpenging_config_callback_arg {
+	charp_ht ht;
+} __attribute__((__transparent_union__));
+
+struct rtpenging_config_callback {
+	enum {
+		RCC_END = 0,
+		RCC_SECTION_KEYS,
+	} type;
+	union rtpenging_config_callback_arg arg;
+	union {
+		struct {
+			char * const *name;
+			void (*callback)(const char *key, char *value,
+					union rtpenging_config_callback_arg);
+		} section_keys;
+	};
+};
+
 
 
 /*** GLOBALS ***/
@@ -69,12 +93,12 @@ void config_load_free(struct rtpengine_common_config *);
 void config_load_ext(int *argc, char ***argv, GOptionEntry *entries, const char *description,
 		char *default_config, char *default_section,
 		struct rtpengine_common_config *,
-		char * const *template_section, GHashTable *templates);
+		const struct rtpenging_config_callback *);
 INLINE void config_load(int *argc, char ***argv, GOptionEntry *entries, const char *description,
 		char *default_config, char *default_section,
 		struct rtpengine_common_config *cc)
 {
-	config_load_ext(argc, argv, entries, description, default_config, default_section, cc, NULL, NULL);
+	config_load_ext(argc, argv, entries, description, default_config, default_section, cc, NULL);
 }
 
 char *get_thread_buf(void);
@@ -113,7 +137,9 @@ INLINE unsigned int c_str_hash(const char *s) {
 INLINE gboolean c_str_equal(const char *a, const char *b) {
 	return g_str_equal(a, b);
 }
-
+INLINE void add_c_str_to_ht(const char *key, char *value, charp_ht ht) {
+	t_hash_table_insert(ht, g_strdup(key), value); // hash table takes ownership of both
+}
 
 /*** MUTEX ABSTRACTION ***/
 

t/test-stats.c

@@ -74,7 +74,7 @@ int main(void) {
 	rtpe_ssl_init();
 	call_init();
 	statistics_init();
-	call_interfaces_init(NULL);
+	call_interfaces_init(charp_ht_null());
 	ice_init();
 	control_ng_init();
 	dtls_init();