Remove global variable that makes dlopen unhappy

This isn't the best way to do this, but it is the easiest. There are some
limitations that are going to need to be addressed at some point with reloads
and when I (or someone else) work on that, then the API can be updated to
handle passing the private config data that the calendar tech modules need in
a better way as well.


git-svn-id: http://svn.digium.com/svn/asterisk/trunk@223016 f38db490-d61c-443f-a65b-d21fe96a405b

5 files changed, 71 insertions, 16 deletions

diff --git a/include/asterisk/calendar.h b/include/asterisk/calendar.h
index dd14f963a..29c67de17 100644
--- a/include/asterisk/calendar.h
+++ b/include/asterisk/calendar.h
@@ -60,8 +60,6 @@
  * to unregister that module's calendar type (usually done in module_unload())
  */
 
-extern struct ast_config *ast_calendar_config;
-
 struct ast_calendar;
 struct ast_calendar_event;
 
@@ -184,4 +182,16 @@ struct ast_calendar_event *ast_calendar_unref_event(struct ast_calendar_event *e
  */
 void ast_calendar_clear_events(struct ast_calendar *cal);
 
+/*! \brief Grab and lock pointer to the calendar config (read only)
+ *
+ * \note ast_calendar_config_release must be called when finished with the pointer
+ *
+ * \return the parsed calendar config
+ */
+const struct ast_config *ast_calendar_config_acquire(void);
+
+/*! \brief Release the calendar config
+ */
+void ast_calendar_config_release(void);
+
 #endif /* _ASTERISK_CALENDAR_H */
diff --git a/res/res_calendar.c b/res/res_calendar.c
index e916ac0f0..6ec7b424c 100644
--- a/res/res_calendar.c
+++ b/res/res_calendar.c
@@ -190,7 +190,25 @@ struct evententry {
 static AST_LIST_HEAD_STATIC(techs, ast_calendar_tech);
 AST_LIST_HEAD_NOLOCK(eventlist, evententry); /* define the type */
 
-struct ast_config *ast_calendar_config;
+static struct ast_config *calendar_config;
+AST_RWLOCK_DEFINE_STATIC(config_lock);
+
+const struct ast_config *ast_calendar_config_acquire(void)
+{
+	ast_rwlock_rdlock(&config_lock);
+
+	if (!calendar_config) {
+		ast_rwlock_unlock(&config_lock);
+		return NULL;
+	}
+
+	return calendar_config;
+}
+
+void ast_calendar_config_release(void)
+{
+	ast_rwlock_unlock(&config_lock);
+}
 
 static struct ast_calendar *unref_calendar(struct ast_calendar *cal)
 {
@@ -390,29 +408,33 @@ static int load_tech_calendars(struct ast_calendar_tech *tech)
 	const char *cat = NULL;
 	const char *val;
 
-	if (!ast_calendar_config) {
+	if (!calendar_config) {
 		ast_log(LOG_WARNING, "Calendar support disabled, not loading %s calendar module\n", tech->type);
 		return -1;
 	}
 
-	while ((cat = ast_category_browse(ast_calendar_config, cat))) {
+	ast_rwlock_wrlock(&config_lock);
+	while ((cat = ast_category_browse(calendar_config, cat))) {
 		if (!strcasecmp(cat, "general")) {
 			continue;
 		}
 
-		if (!(val = ast_variable_retrieve(ast_calendar_config, cat, "type")) || strcasecmp(val, tech->type)) {
+		if (!(val = ast_variable_retrieve(calendar_config, cat, "type")) || strcasecmp(val, tech->type)) {
 			continue;
 		}
 
 		/* A serious error occurred loading calendars from this tech and it should be disabled */
-		if (!(cal = build_calendar(ast_calendar_config, cat, tech))) {
+		if (!(cal = build_calendar(calendar_config, cat, tech))) {
 			ast_calendar_unregister(tech);
+			ast_rwlock_unlock(&config_lock);
 			return -1;
 		}
 
 		cal = unref_calendar(cal);
 	}
 
+	ast_rwlock_unlock(&config_lock);
+
 	return 0;
 }
 
@@ -862,11 +884,13 @@ static int load_config(void *data)
 		return 0;
 	}
 
-	if (ast_calendar_config) {
-		ast_config_destroy(ast_calendar_config);
+	ast_rwlock_wrlock(&config_lock);
+	if (calendar_config) {
+		ast_config_destroy(calendar_config);
 	}
 
-	ast_calendar_config = tmpcfg;
+	calendar_config = tmpcfg;
+	ast_rwlock_unlock(&config_lock);
 
 	return 0;
 }
diff --git a/res/res_calendar_caldav.c b/res/res_calendar_caldav.c
index 64f8f2aa1..2b3f5a334 100644
--- a/res/res_calendar_caldav.c
+++ b/res/res_calendar_caldav.c
@@ -536,11 +536,12 @@ static int verify_cert(void *userdata, int failures, const ne_ssl_certificate *c
 static void *caldav_load_calendar(void *void_data)
 {
 	struct caldav_pvt *pvt;
+	const struct ast_config *cfg;
 	struct ast_variable *v;
 	struct ast_calendar *cal = void_data;
 	ast_mutex_t refreshlock;
 
-	if (!(cal && ast_calendar_config)) {
+	if (!(cal && (cfg = ast_calendar_config_acquire()))) {
 		ast_log(LOG_ERROR, "You must enable calendar support for res_caldav to load\n");
 		return NULL;
 	}
@@ -551,11 +552,13 @@ static void *caldav_load_calendar(void *void_data)
 		} else {
 			ast_log(LOG_WARNING, "Could not lock calendar, aborting!\n");
 		}
+		ast_calendar_config_release();
 		return NULL;
 	}
 
 	if (!(pvt = ao2_alloc(sizeof(*pvt), caldav_destructor))) {
 		ast_log(LOG_ERROR, "Could not allocate caldav_pvt structure for calendar: %s\n", cal->name);
+		ast_calendar_config_release();
 		return NULL;
 	}
 
@@ -565,6 +568,7 @@ static void *caldav_load_calendar(void *void_data)
 		ast_log(LOG_ERROR, "Could not allocate space for fetching events for calendar: %s\n", cal->name);
 		pvt = unref_caldav(pvt);
 		ao2_unlock(cal);
+		ast_calendar_config_release();
 		return NULL;
 	}
 
@@ -572,10 +576,11 @@ static void *caldav_load_calendar(void *void_data)
 		ast_log(LOG_ERROR, "Couldn't allocate string field space for calendar: %s\n", cal->name);
 		pvt = unref_caldav(pvt);
 		ao2_unlock(cal);
+		ast_calendar_config_release();
 		return NULL;
 	}
 
-	for (v = ast_variable_browse(ast_calendar_config, cal->name); v; v = v->next) {
+	for (v = ast_variable_browse(cfg, cal->name); v; v = v->next) {
 		if (!strcasecmp(v->name, "url")) {
 			ast_string_field_set(pvt, url, v->value);
 		} else if (!strcasecmp(v->name, "user")) {
@@ -585,6 +590,8 @@ static void *caldav_load_calendar(void *void_data)
 		}
 	}
 
+	ast_calendar_config_release();
+
 	if (ast_strlen_zero(pvt->url)) {
 		ast_log(LOG_WARNING, "No URL was specified for CalDAV calendar '%s' - skipping.\n", cal->name);
 		pvt = unref_caldav(pvt);
diff --git a/res/res_calendar_exchange.c b/res/res_calendar_exchange.c
index 0b4e661e2..05a42633a 100644
--- a/res/res_calendar_exchange.c
+++ b/res/res_calendar_exchange.c
@@ -619,11 +619,12 @@ static int update_exchangecal(struct exchangecal_pvt *pvt)
 static void *exchangecal_load_calendar(void *void_data)
 {
 	struct exchangecal_pvt *pvt;
+	const struct ast_config *cfg;
 	struct ast_variable *v;
 	struct ast_calendar *cal = void_data;
 	ast_mutex_t refreshlock;
 
-	if (!(cal && ast_calendar_config)) {
+	if (!(cal && (cfg = ast_calendar_config_acquire()))) {
 		ast_log(LOG_ERROR, "You must enable calendar support for res_exchangecal to load\n");
 		return NULL;
 	}
@@ -634,11 +635,13 @@ static void *exchangecal_load_calendar(void *void_data)
 		} else {
 			ast_log(LOG_WARNING, "Could not lock calendar, aborting!\n");
 		}
+		ast_calendar_config_release();
 		return NULL;
 	}
 
 	if (!(pvt = ao2_alloc(sizeof(*pvt), exchangecal_destructor))) {
 		ast_log(LOG_ERROR, "Could not allocate exchangecal_pvt structure for calendar: %s\n", cal->name);
+		ast_calendar_config_release();
 		return NULL;
 	}
 
@@ -648,6 +651,7 @@ static void *exchangecal_load_calendar(void *void_data)
 		ast_log(LOG_ERROR, "Could not allocate space for fetching events for calendar: %s\n", cal->name);
 		pvt = unref_exchangecal(pvt);
 		ao2_unlock(cal);
+		ast_calendar_config_release();
 		return NULL;
 	}
 
@@ -655,10 +659,11 @@ static void *exchangecal_load_calendar(void *void_data)
 		ast_log(LOG_ERROR, "Couldn't allocate string field space for calendar: %s\n", cal->name);
 		pvt = unref_exchangecal(pvt);
 		ao2_unlock(cal);
+		ast_calendar_config_release();
 		return NULL;
 	}
 
-	for (v = ast_variable_browse(ast_calendar_config, cal->name); v; v = v->next) {
+	for (v = ast_variable_browse(cfg, cal->name); v; v = v->next) {
 		if (!strcasecmp(v->name, "url")) {
 			ast_string_field_set(pvt, url, v->value);
 		} else if (!strcasecmp(v->name, "user")) {
@@ -668,6 +673,8 @@ static void *exchangecal_load_calendar(void *void_data)
 		}
 	}
 
+	ast_calendar_config_release();
+
 	if (ast_strlen_zero(pvt->url)) {
 		ast_log(LOG_WARNING, "No URL was specified for Exchange calendar '%s' - skipping.\n", cal->name);
 		pvt = unref_exchangecal(pvt);
diff --git a/res/res_calendar_icalendar.c b/res/res_calendar_icalendar.c
index 86024b27a..97c3253ab 100644
--- a/res/res_calendar_icalendar.c
+++ b/res/res_calendar_icalendar.c
@@ -324,11 +324,12 @@ static void icalendar_add_event(icalcomponent *comp, struct icaltime_span *span,
 static void *ical_load_calendar(void *void_data)
 {
 	struct icalendar_pvt *pvt;
+	const struct ast_config *cfg;
 	struct ast_variable *v;
 	struct ast_calendar *cal = void_data;
 	ast_mutex_t refreshlock;
 
-	if (!(cal && ast_calendar_config)) {
+	if (!(cal && (cfg = ast_calendar_config_acquire()))) {
 		ast_log(LOG_ERROR, "You must enable calendar support for res_icalendar to load\n");
 		return NULL;
 	}
@@ -338,11 +339,13 @@ static void *ical_load_calendar(void *void_data)
 		} else {
 			ast_log(LOG_WARNING, "Could not lock calendar, aborting!\n");
 		}
+		ast_calendar_config_release();
 		return NULL;
 	}
 
 	if (!(pvt = ao2_alloc(sizeof(*pvt), icalendar_destructor))) {
 		ast_log(LOG_ERROR, "Could not allocate icalendar_pvt structure for calendar: %s\n", cal->name);
+		ast_calendar_config_release();
 		return NULL;
 	}
 
@@ -352,6 +355,7 @@ static void *ical_load_calendar(void *void_data)
 		ast_log(LOG_ERROR, "Could not allocate space for fetching events for calendar: %s\n", cal->name);
 		pvt = unref_icalendar(pvt);
 		ao2_unlock(cal);
+		ast_calendar_config_release();
 		return NULL;
 	}
 
@@ -359,10 +363,11 @@ static void *ical_load_calendar(void *void_data)
 		ast_log(LOG_ERROR, "Couldn't allocate string field space for calendar: %s\n", cal->name);
 		pvt = unref_icalendar(pvt);
 		ao2_unlock(cal);
+		ast_calendar_config_release();
 		return NULL;
 	}
 
-	for (v = ast_variable_browse(ast_calendar_config, cal->name); v; v = v->next) {
+	for (v = ast_variable_browse(cfg, cal->name); v; v = v->next) {
 		if (!strcasecmp(v->name, "url")) {
 			ast_string_field_set(pvt, url, v->value);
 		} else if (!strcasecmp(v->name, "user")) {
@@ -372,6 +377,8 @@ static void *ical_load_calendar(void *void_data)
 		}
 	}
 
+	ast_calendar_config_release();
+
 	if (ast_strlen_zero(pvt->url)) {
 		ast_log(LOG_WARNING, "No URL was specified for iCalendar '%s' - skipping.\n", cal->name);
 		pvt = unref_icalendar(pvt);