Make context reference counted

Instead of only allowing one owner keeping a libinput context alive,
make context reference counted, replacing libinput_destroy() with
libinput_unref() while adding another function libinput_ref().

Even though there might not be any current use cases, it doesn't mean we
should hard code this usage model in the API. The old behaviour can be
emulated by never calling libinput_ref() while replacing
libinput_destroy() with libinput_unref().

Signed-off-by: Jonas Ådahl <jadahl@gmail.com>
Reviewed-by: Peter Hutterer <peter.hutterer@who-t.net>
Signed-off-by: Peter Hutterer <peter.hutterer@who-t.net>

diff --git a/src/libinput-private.h b/src/libinput-private.h
index f0bda1f..cfe6535 100644 (file)
--- a/src/libinput-private.h
+++ b/src/libinput-private.h
@@ -57,6 +57,7 @@ struct libinput {
        const struct libinput_interface *interface;
        const struct libinput_interface_backend *interface_backend;
        void *user_data;
+       int refcount;
 };
 
 typedef void (*libinput_seat_destroy_func) (struct libinput_seat *seat);

diff --git a/src/libinput.c b/src/libinput.c
index d4d5711..3aeca7d 100644 (file)
--- a/src/libinput.c
+++ b/src/libinput.c
@@ -502,6 +502,7 @@ libinput_init(struct libinput *libinput,
        libinput->interface = interface;
        libinput->interface_backend = interface_backend;
        libinput->user_data = user_data;
+       libinput->refcount = 1;
        list_init(&libinput->source_destroy_list);
        list_init(&libinput->seat_list);
 
@@ -530,15 +531,27 @@ libinput_drop_destroyed_sources(struct libinput *libinput)
        list_init(&libinput->source_destroy_list);
 }
 
-LIBINPUT_EXPORT void
-libinput_destroy(struct libinput *libinput)
+LIBINPUT_EXPORT struct libinput *
+libinput_ref(struct libinput *libinput)
+{
+       libinput->refcount++;
+       return libinput;
+}
+
+LIBINPUT_EXPORT struct libinput *
+libinput_unref(struct libinput *libinput)
 {
        struct libinput_event *event;
        struct libinput_device *device, *next_device;
        struct libinput_seat *seat, *next_seat;
 
        if (libinput == NULL)
-               return;
+               return NULL;
+
+       assert(libinput->refcount > 0);
+       libinput->refcount--;
+       if (libinput->refcount > 0)
+               return libinput;
 
        libinput_suspend(libinput);
 
@@ -562,6 +575,8 @@ libinput_destroy(struct libinput *libinput)
        libinput_drop_destroyed_sources(libinput);
        close(libinput->epoll_fd);
        free(libinput);
+
+       return NULL;
 }
 
 LIBINPUT_EXPORT void

diff --git a/src/libinput.h b/src/libinput.h
index 3503b76..72375f7 100644 (file)
--- a/src/libinput.h
+++ b/src/libinput.h
@@ -793,6 +793,9 @@ struct libinput_interface {
  * device are ignored. Such devices and those that failed to open
  * ignored until the next call to libinput_resume().
  *
+ * The reference count of the context is initialized to 1. See @ref
+ * libinput_unref.
+ *
  * @param interface The callback interface
  * @param user_data Caller-specific data passed to the various callback
  * interfaces.
@@ -818,6 +821,9 @@ libinput_udev_create_for_seat(const struct libinput_interface *interface,
  * The context is fully initialized but will not generate events until at
  * least one device has been added.
  *
+ * The reference count of the context is initialized to 1. See @ref
+ * libinput_unref.
+ *
  * @param interface The callback interface
  * @param user_data Caller-specific data passed to the various callback
  * interfaces.
@@ -967,13 +973,27 @@ libinput_suspend(struct libinput *libinput);
 /**
  * @ingroup base
  *
- * Destroy the libinput context. After this, object references associated with
- * the destroyed context are invalid and may not be interacted with.
+ * Add a reference to the context. A context is destroyed whenever the
+ * reference count reaches 0. See @ref libinput_unref.
+ *
+ * @param libinput A previously initialized valid libinput context
+ * @return The passed libinput context
+ */
+struct libinput *
+libinput_ref(struct libinput *libinput);
+
+/**
+ * @ingroup base
+ *
+ * Dereference the libinput context. After this, the context may have been
+ * destroyed, if the last reference was dereferenced. If so, the context is
+ * invalid and may not be interacted with.
  *
  * @param libinput A previously initialized libinput context
+ * @return NULL if context was destroyed otherwise the passed context
  */
-void
-libinput_destroy(struct libinput *libinput);
+struct libinput *
+libinput_unref(struct libinput *libinput);
 
 /**
  * @ingroup base

diff --git a/src/udev-seat.c b/src/udev-seat.c
index 38a13b7..5b61dee 100644 (file)
--- a/src/udev-seat.c
+++ b/src/udev-seat.c
@@ -358,7 +358,7 @@ libinput_udev_create_for_seat(const struct libinput_interface *interface,
 
        if (udev_input_enable(&input->base) < 0) {
                udev_unref(udev);
-               libinput_destroy(&input->base);
+               libinput_unref(&input->base);
                free(input);
                return NULL;
        }

diff --git a/test/keyboard.c b/test/keyboard.c
index a518b66..83153bb 100644 (file)
--- a/test/keyboard.c
+++ b/test/keyboard.c
@@ -108,7 +108,7 @@ START_TEST(keyboard_seat_key_count)
 
        for (i = 0; i < num_devices; ++i)
                litest_delete_device(devices[i]);
-       libinput_destroy(libinput);
+       libinput_unref(libinput);
 }
 END_TEST
 

diff --git a/test/litest.c b/test/litest.c
index 0a9cc72..55ba678 100644 (file)
--- a/test/litest.c
+++ b/test/litest.c
@@ -573,7 +573,7 @@ litest_delete_device(struct litest_device *d)
 
        libinput_device_unref(d->libinput_device);
        if (d->owns_context)
-               libinput_destroy(d->libinput);
+               libinput_unref(d->libinput);
        libevdev_free(d->evdev);
        libevdev_uinput_destroy(d->uinput);
        memset(d,0, sizeof(*d));

diff --git a/test/log.c b/test/log.c
index a281820..fe67d68 100644 (file)
--- a/test/log.c
+++ b/test/log.c
@@ -86,7 +86,7 @@ START_TEST(log_handler_invoked)
        ck_assert_int_gt(log_handler_called, 0);
        log_handler_called = 0;
 
-       libinput_destroy(li);
+       libinput_unref(li);
        libinput_log_set_priority(pri);
 }
 END_TEST
@@ -106,7 +106,7 @@ START_TEST(log_userdata_NULL)
        ck_assert_int_gt(log_handler_called, 0);
        log_handler_called = 0;
 
-       libinput_destroy(li);
+       libinput_unref(li);
 
        libinput_log_set_priority(pri);
 }
@@ -127,7 +127,7 @@ START_TEST(log_userdata)
        ck_assert_int_gt(log_handler_called, 0);
        log_handler_called = 0;
 
-       libinput_destroy(li);
+       libinput_unref(li);
        libinput_log_set_priority(pri);
 }
 END_TEST
@@ -148,7 +148,7 @@ START_TEST(log_handler_NULL)
        log_handler_called = 0;
        libinput_log_set_handler(simple_log_handler, NULL);
 
-       libinput_destroy(li);
+       libinput_unref(li);
        libinput_log_set_priority(pri);
 }
 END_TEST
@@ -173,7 +173,7 @@ START_TEST(log_priority)
 
        log_handler_called = 0;
 
-       libinput_destroy(li);
+       libinput_unref(li);
        libinput_log_set_priority(pri);
 }
 END_TEST

diff --git a/test/misc.c b/test/misc.c
index 133bdb6..ad2e1f6 100644 (file)
--- a/test/misc.c
+++ b/test/misc.c
@@ -133,7 +133,7 @@ START_TEST(event_conversion_device_notify)
                libinput_event_destroy(event);
        }
 
-       libinput_destroy(li);
+       libinput_unref(li);
        libevdev_uinput_destroy(uinput);
 
        ck_assert_int_gt(device_added, 0);
@@ -194,7 +194,7 @@ START_TEST(event_conversion_pointer)
                libinput_event_destroy(event);
        }
 
-       libinput_destroy(li);
+       libinput_unref(li);
        libevdev_uinput_destroy(uinput);
 
        ck_assert_int_gt(motion, 0);
@@ -254,7 +254,7 @@ START_TEST(event_conversion_pointer_abs)
                libinput_event_destroy(event);
        }
 
-       libinput_destroy(li);
+       libinput_unref(li);
        libevdev_uinput_destroy(uinput);
 
        ck_assert_int_gt(motion, 0);
@@ -304,7 +304,7 @@ START_TEST(event_conversion_key)
                libinput_event_destroy(event);
        }
 
-       libinput_destroy(li);
+       libinput_unref(li);
        libevdev_uinput_destroy(uinput);
 
        ck_assert_int_gt(key, 0);
@@ -364,7 +364,7 @@ START_TEST(event_conversion_touch)
                libinput_event_destroy(event);
        }
 
-       libinput_destroy(li);
+       libinput_unref(li);
        libevdev_uinput_destroy(uinput);
 
        ck_assert_int_gt(touch, 0);

diff --git a/test/path.c b/test/path.c
index 24f60e0..99b474e 100644 (file)
--- a/test/path.c
+++ b/test/path.c
@@ -65,7 +65,7 @@ START_TEST(path_create_NULL)
        ck_assert(li == NULL);
        li = libinput_path_create_context(&simple_interface, NULL);
        ck_assert(li != NULL);
-       libinput_destroy(li);
+       libinput_unref(li);
 
        ck_assert_int_eq(open_func_count, 0);
        ck_assert_int_eq(close_func_count, 0);
@@ -92,7 +92,7 @@ START_TEST(path_create_invalid)
        ck_assert_int_eq(open_func_count, 0);
        ck_assert_int_eq(close_func_count, 0);
 
-       libinput_destroy(li);
+       libinput_unref(li);
        ck_assert_int_eq(close_func_count, 0);
 
        open_func_count = 0;
@@ -126,7 +126,7 @@ START_TEST(path_create_destroy)
        ck_assert_int_eq(open_func_count, 1);
 
        libevdev_uinput_destroy(uinput);
-       libinput_destroy(li);
+       libinput_unref(li);
        ck_assert_int_eq(close_func_count, 1);
 
        open_func_count = 0;
@@ -372,7 +372,7 @@ START_TEST(path_suspend)
        libinput_resume(li);
 
        libevdev_uinput_destroy(uinput);
-       libinput_destroy(li);
+       libinput_unref(li);
 
        open_func_count = 0;
        close_func_count = 0;
@@ -406,7 +406,7 @@ START_TEST(path_double_suspend)
        libinput_resume(li);
 
        libevdev_uinput_destroy(uinput);
-       libinput_destroy(li);
+       libinput_unref(li);
 
        open_func_count = 0;
        close_func_count = 0;
@@ -440,7 +440,7 @@ START_TEST(path_double_resume)
        libinput_resume(li);
 
        libevdev_uinput_destroy(uinput);
-       libinput_destroy(li);
+       libinput_unref(li);
 
        open_func_count = 0;
        close_func_count = 0;
@@ -523,7 +523,7 @@ START_TEST(path_add_device_suspend_resume)
 
        libevdev_uinput_destroy(uinput1);
        libevdev_uinput_destroy(uinput2);
-       libinput_destroy(li);
+       libinput_unref(li);
 
        open_func_count = 0;
        close_func_count = 0;
@@ -614,7 +614,7 @@ START_TEST(path_add_device_suspend_resume_fail)
        ck_assert_int_eq(nevents, 2);
 
        libevdev_uinput_destroy(uinput2);
-       libinput_destroy(li);
+       libinput_unref(li);
 
        open_func_count = 0;
        close_func_count = 0;
@@ -704,7 +704,7 @@ START_TEST(path_add_device_suspend_resume_remove_device)
        ck_assert_int_eq(nevents, 1);
 
        libevdev_uinput_destroy(uinput1);
-       libinput_destroy(li);
+       libinput_unref(li);
 
        open_func_count = 0;
        close_func_count = 0;
@@ -790,7 +790,7 @@ START_TEST(path_seat_recycle)
 
        ck_assert(found == 1);
 
-       libinput_destroy(li);
+       libinput_unref(li);
 
        libevdev_uinput_destroy(uinput);
 }

diff --git a/test/pointer.c b/test/pointer.c
index 346e59b..7d5668f 100644 (file)
--- a/test/pointer.c
+++ b/test/pointer.c
@@ -292,7 +292,7 @@ START_TEST(pointer_seat_button_count)
 
        for (i = 0; i < num_devices; ++i)
                litest_delete_device(devices[i]);
-       libinput_destroy(libinput);
+       libinput_unref(libinput);
 }
 END_TEST
 

diff --git a/test/udev.c b/test/udev.c
index 6af2cb0..09c2a94 100644 (file)
--- a/test/udev.c
+++ b/test/udev.c
@@ -97,7 +97,7 @@ START_TEST(udev_create_seat0)
        ck_assert(event != NULL);
 
        libinput_event_destroy(event);
-       libinput_destroy(li);
+       libinput_unref(li);
        udev_unref(udev);
 }
 END_TEST
@@ -124,7 +124,7 @@ START_TEST(udev_create_empty_seat)
        ck_assert(event == NULL);
 
        libinput_event_destroy(event);
-       libinput_destroy(li);
+       libinput_unref(li);
        udev_unref(udev);
 }
 END_TEST
@@ -169,7 +169,7 @@ START_TEST(udev_added_seat_default)
 
        ck_assert(default_seat_found);
 
-       libinput_destroy(li);
+       libinput_unref(li);
        udev_unref(udev);
 }
 END_TEST
@@ -200,7 +200,7 @@ START_TEST(udev_double_suspend)
        libinput_resume(li);
 
        libinput_event_destroy(event);
-       libinput_destroy(li);
+       libinput_unref(li);
        udev_unref(udev);
 }
 END_TEST
@@ -231,7 +231,7 @@ START_TEST(udev_double_resume)
        libinput_resume(li);
 
        libinput_event_destroy(event);
-       libinput_destroy(li);
+       libinput_unref(li);
        udev_unref(udev);
 }
 END_TEST
@@ -289,7 +289,7 @@ START_TEST(udev_suspend_resume)
        process_events_count_devices(li, &num_devices);
        ck_assert_int_gt(num_devices, 0);
 
-       libinput_destroy(li);
+       libinput_unref(li);
        udev_unref(udev);
 }
 END_TEST
@@ -322,7 +322,7 @@ START_TEST(udev_device_sysname)
                libinput_event_destroy(ev);
        }
 
-       libinput_destroy(li);
+       libinput_unref(li);
        udev_unref(udev);
 }
 END_TEST
@@ -396,7 +396,7 @@ START_TEST(udev_seat_recycle)
 
        ck_assert(found == 1);
 
-       libinput_destroy(li);
+       libinput_unref(li);
        udev_unref(udev);
 }
 END_TEST

diff --git a/tools/event-debug.c b/tools/event-debug.c
index 34acfce..95e7628 100644 (file)
--- a/tools/event-debug.c
+++ b/tools/event-debug.c
@@ -163,7 +163,7 @@ open_device(struct libinput **li, const char *path)
        device = libinput_path_add_device(*li, path);
        if (!device) {
                fprintf(stderr, "Failed to initialized device %s\n", path);
-               libinput_destroy(*li);
+               libinput_unref(*li);
                return 1;
        }
 
@@ -478,7 +478,7 @@ main(int argc, char **argv)
 
        mainloop(li);
 
-       libinput_destroy(li);
+       libinput_unref(li);
        if (udev)
                udev_unref(udev);
 

diff --git a/tools/event-gui.c b/tools/event-gui.c
index 9554093..9c39c21 100644 (file)
--- a/tools/event-gui.c
+++ b/tools/event-gui.c
@@ -467,7 +467,7 @@ main(int argc, char *argv[])
 
        gtk_main();
 
-       libinput_destroy(li);
+       libinput_unref(li);
        udev_unref(udev);
 
        return 0;