libei: switch to a single ei_new() function

The main reason for having different functions to create the initial context
was so we can nest the ei struct inside the context-specific struct. That
shouldn't leak into the API though and our use-case is probably one where we
create one context, then iterate through possible backends until one succeds -
having different contexts here doesn't help then.

Signed-off-by: Peter Hutterer <peter.hutterer@who-t.net>

src/libei-private.h

@@ -29,8 +29,8 @@
 #include "util-list.h"
 #include "util-sources.h"
 
-struct ei_backend {
-	void (*destroy)(struct ei *ei);
+struct ei_backend_interface {
+	void (*destroy)(struct ei *ei, void *backend);
 };
 
 enum ei_state {
@@ -46,7 +46,8 @@ struct ei {
 	struct logger *logger;
 	struct sink *sink;
 	struct source *source;
-	struct ei_backend backend;
+	struct ei_backend_interface backend_interface;
+	void *backend;
 	enum ei_state state;
 	struct list event_queue;
 	struct list devices;

src/libei-socket.c

@@ -35,51 +35,53 @@
 #include "util-macros.h"
 #include "util-sources.h"
 #include "util-strings.h"
+#include "util-object.h"
 
 #include "libei.h"
 #include "libei-private.h"
 
 struct ei_socket {
-	struct ei base;
+	struct object object;
 	struct source *connection;
 };
 
 static inline struct ei_socket *
 ei_socket(struct ei *ei)
 {
-	return container_of(ei, struct ei_socket, base);
+	return ei->backend;
 }
 
+static inline void
+ei_socket_destroy(struct ei_socket *socket)
+{
+	socket->connection = source_unref(socket->connection);
+}
+
+OBJECT_IMPLEMENT_CREATE(ei_socket);
+static
+OBJECT_IMPLEMENT_UNREF(ei_socket);
+
 static void
-socket_destroy(struct ei *ei)
+interface_socket_destroy(struct ei *ei, void *backend)
 {
+	struct ei_socket *socket = backend;
+	ei_socket_unref(socket);
 }
 
-const struct ei_backend backend = {
-	.destroy = socket_destroy,
+static const struct ei_backend_interface interface = {
+	.destroy = interface_socket_destroy,
 };
 
-_public_ struct ei *
-ei_socket_new_context(void *user_data)
-{
-	struct ei_socket *ctx = xalloc(sizeof *ctx);
-
-	ei_init_object(&ctx->base, NULL);
-
-	ctx->base.user_data = user_data;
-	ctx->base.backend = backend;
-
-	return &ctx->base;
-}
-
 _public_ int
 ei_socket_init(struct ei *ei, const char *socketpath)
 {
 	assert(ei);
+	assert(!ei->backend);
 
-	int rc = ei_init(ei);
-	if (rc)
-		return -rc;
+	struct ei_socket *ei_socket = ei_socket_create(&ei->object);
+
+	ei->backend = ei_socket;
+	ei->backend_interface = interface;
 
 	if (!socketpath)
 		socketpath = getenv("LIBEI_SOCKET");

src/libei.c

@@ -114,13 +114,14 @@ static void
 ei_destroy(struct ei *ei)
 {
 	ei->logger = logger_unref(ei->logger);
-	if (ei->backend.destroy)
-		ei->backend.destroy(ei);
+	if (ei->backend_interface.destroy)
+		ei->backend_interface.destroy(ei, ei->backend);
+	ei->backend = NULL;
 	sink_unref(ei->sink);
 	free(ei->name);
 }
 
-OBJECT_IMPLEMENT_INIT(ei);
+OBJECT_IMPLEMENT_CREATE(ei);
 _public_
 OBJECT_IMPLEMENT_REF(ei);
 _public_
@@ -130,10 +131,11 @@ _public_
 OBJECT_IMPLEMENT_SETTER(ei, user_data, void *);
 OBJECT_IMPLEMENT_GETTER(ei, user_data, void *);
 
-int
-ei_init(struct ei *ei)
+_public_ struct ei *
+ei_new(void *user_data)
 {
-	ei_init_object(ei, NULL);
+	_cleanup_ei_ struct ei *ei = ei_create(NULL);
+
 	ei->state = EI_STATE_NEW;
 	list_init(&ei->event_queue);
 	list_init(&ei->devices);
@@ -142,9 +144,12 @@ ei_init(struct ei *ei)
 	logger_set_priority(ei->logger, LOGGER_DEBUG);
 	ei->sink = sink_new();
 	if (!ei->sink)
-		return -EMFILE;
+		return NULL;
 
-	return 0;
+	ei->user_data = user_data;
+	ei->backend = NULL;
+
+	return steal(&ei);
 }
 
 _public_ int
@@ -716,9 +721,7 @@ static MunitResult
 test_init_unref(const MunitParameter params[], void *user_data)
 {
 	/* need to alloc here so unref can free */
-	struct ei *ei = xalloc(sizeof(*ei));
-
-	ei_init(ei);
+	struct ei *ei = ei_new(NULL);
 
 	munit_assert_int(ei->state, ==, EI_STATE_NEW);
 	munit_assert(list_empty(&ei->event_queue));

src/libei.h

@@ -108,9 +108,9 @@ ei_new(void *user_data);
 void
 ei_configure_name(struct ei * ei, const char *name);
 
-struct ei *
-ei_socket_new_context(void *user_data);
-
+/**
+ * Initialize the ei context with a named socket as backend.
+ */
 int
 ei_socket_init(struct ei *ei, const char *socketpath);
 

tools/ei-socket-client.c

@@ -38,7 +38,7 @@
 int main(int argc, char **argv)
 {
 	const char SOCKETNAME[] = "eis.socket";
-	struct ei *ei = ei_socket_new_context(NULL);
+	struct ei *ei = ei_new(NULL);
 	assert(ei);
 
 	ei_configure_name(ei, "ei-socket-client-demo");