weston-log: Add a advertised list of debug scopes

This introduces a new list that is being checked up when advertising
or when the client attempts to bind a debug scope.

This would allow for a way in which the frontend can determine which
debug scopes the weston-debug protocol can advertise or the client
using the protocol can bind to.

Signed-off-by: Marius Vlad <marius.vlad@collabora.com>

frontend/main.c

@@ -4438,6 +4438,22 @@ weston_log_setup_scopes(struct weston_log_context *log_ctx,
 	free(tokenize);
 }
 
+static void
+weston_log_print_all_advertised_scopes(struct weston_compositor *ec)
+{
+	struct weston_log_scope *nscope = NULL;
+
+	weston_log("Currently advertised debug scopes:\n");
+
+	while ((nscope = weston_log_scopes_iterate(ec->weston_log_ctx, nscope))) {
+		const char *name = weston_log_scope_get_name(nscope);
+		const char *desc = weston_log_scope_get_description(nscope);
+
+		if (weston_log_scope_to_be_advertised(ec->weston_log_ctx, name)) 
+			weston_log_continue(STAMP_SPACE "'%s' - %s", name, desc);
+	}
+}
+
 static void
 flight_rec_key_binding_handler(struct weston_keyboard *keyboard,
 			       const struct timespec *time, uint32_t key,
@@ -4814,6 +4830,9 @@ wet_main(int argc, char *argv[], const struct weston_testsuite_data *test_data)
 
 	load_additional_modules(wet);
 
+	if (debug_protocol)
+		weston_log_print_all_advertised_scopes(wet.compositor);
+
 	section = weston_config_get_section(config, "keyboard", NULL, NULL);
 	weston_config_section_get_bool(section, "numlock-on", &numlock_on, false);
 	if (numlock_on) {

include/libweston/libweston.h

@@ -1401,6 +1401,7 @@ struct weston_compositor {
 	struct weston_log_scope *debug_scene;
 	struct weston_log_scope *timeline;
 	struct weston_log_scope *libseat_debug;
+	struct weston_log_filtered *advertised_log_scopes;
 
 	struct content_protection *content_protection;
 

include/libweston/weston-log.h

@@ -146,6 +146,12 @@ struct weston_log_scope *
 weston_log_scopes_iterate(struct weston_log_context *log_ctx,
                           struct weston_log_scope *nscope);
 
+void
+weston_add_scope_to_advertised_list(struct weston_log_context *ctx,
+				      const char *name);
+bool
+weston_log_scope_to_be_advertised(struct weston_log_context *ctx, const char *name);
+
 #ifdef  __cplusplus
 }
 #endif

libweston/weston-log-wayland.c

@@ -244,6 +244,10 @@ weston_debug_subscribe(struct wl_client *client,
 	log_ctx = wl_resource_get_user_data(global_resource);
 	version = wl_resource_get_version(global_resource);
 
+	/* verify that we can actually bind to this scope name */
+	if (!weston_log_scope_to_be_advertised(log_ctx, name))
+		goto fail;
+
 	stream_resource = wl_resource_create(client,
 					&weston_debug_stream_v1_interface,
 					version, new_stream_id);

libweston/weston-log.c

@@ -69,6 +69,7 @@ struct weston_log_context {
 	struct wl_listener compositor_destroy_listener;
 	struct wl_list scope_list; /**< weston_log_scope::compositor_link */
 	struct wl_list pending_subscription_list; /**< weston_log_subscription::source_link */
+	struct wl_list advertised_debug_list; /** weston_debug_scope_advertised::link */
 };
 
 /** weston-log message scope
@@ -118,6 +119,15 @@ struct weston_log_subscription {
 	void *data;
 };
 
+struct weston_debug_scope_advertised {
+	const char *name;
+	struct wl_list link; /** weston_log_context::advertised_debug_list */
+};
+
+static void
+weston_destroy_scopes_from_advertised_list(struct weston_log_context *ctx);
+
+
 static struct weston_log_subscription *
 find_pending_subscription(struct weston_log_context *log_ctx,
 			  const char *scope_name)
@@ -372,8 +382,10 @@ weston_debug_protocol_advertise_scopes(struct weston_log_context *log_ctx,
 				       struct wl_resource *res)
 {
 	struct weston_log_scope *scope;
+
 	wl_list_for_each(scope, &log_ctx->scope_list, compositor_link)
-		weston_debug_v1_send_available(res, scope->name, scope->desc);
+		if (weston_log_scope_to_be_advertised(log_ctx, scope->name))
+			weston_debug_v1_send_available(res, scope->name, scope->desc);
 }
 
 /** Disable debug-protocol
@@ -413,6 +425,7 @@ weston_log_ctx_create(void)
 	wl_list_init(&log_ctx->scope_list);
 	wl_list_init(&log_ctx->pending_subscription_list);
 	wl_list_init(&log_ctx->compositor_destroy_listener.link);
+	wl_list_init(&log_ctx->advertised_debug_list);
 
 	return log_ctx;
 }
@@ -449,6 +462,8 @@ weston_log_ctx_destroy(struct weston_log_context *log_ctx)
 		weston_log_subscription_destroy_pending(pending_sub);
 	}
 
+	weston_destroy_scopes_from_advertised_list(log_ctx);
+
 	/* pending_subscription_list should be empty at this point */
 
 	free(log_ctx);
@@ -522,6 +537,22 @@ weston_compositor_is_debug_protocol_enabled(struct weston_compositor *wc)
 	return wc->weston_log_ctx->global != NULL;
 }
 
+WL_EXPORT bool
+weston_log_scope_to_be_advertised(struct weston_log_context *ctx, const char *name)
+{
+	struct weston_debug_scope_advertised *entry;
+
+	if (wl_list_empty(&ctx->advertised_debug_list))
+		return true;
+
+	wl_list_for_each(entry, &ctx->advertised_debug_list, link) {
+		if (!strcmp(entry->name, name))
+			return true;
+	}
+
+	return false;
+}
+
 /** Register a new stream name, creating a log scope.
  *
  * @param log_ctx The weston_log_context where to add.
@@ -670,6 +701,33 @@ weston_compositor_add_log_scope(struct weston_compositor *compositor,
 	return scope;
 }
 
+WL_EXPORT void
+weston_add_scope_to_advertised_list(struct weston_log_context *ctx, const char *name)
+{
+	struct weston_debug_scope_advertised *advertised_scope;
+
+	if (!name || !*name)
+		return;
+
+	advertised_scope = zalloc(sizeof(*advertised_scope));
+	advertised_scope->name = strdup(name);
+
+	wl_list_insert(&ctx->advertised_debug_list, &advertised_scope->link);
+}
+
+static void
+weston_destroy_scopes_from_advertised_list(struct weston_log_context *ctx)
+{
+	struct weston_debug_scope_advertised *entry, *tmp_entry;
+
+	wl_list_for_each_safe(entry, tmp_entry, &ctx->advertised_debug_list, link) {
+		free((char *) entry->name);
+		wl_list_remove(&entry->link);
+		free(entry);
+	}
+
+}
+
 /** Destroy a log scope
  *
  * @param scope The log scope to destroy; may be NULL.