From e6cb11d8825c740f6c50e2d04965e86281b83da9 Mon Sep 17 00:00:00 2001
From: Simon Ser <contact@emersion.fr>
Date: Thu, 1 Jul 2021 10:08:56 +0200
Subject: [PATCH] backend/libinput: stop using wlr_list internally

---
 backend/libinput/backend.c | 18 ++++++------------
 backend/libinput/events.c  | 18 ++++++++++++++----
 include/backend/libinput.h |  3 +--
 3 files changed, 21 insertions(+), 18 deletions(-)

diff --git a/backend/libinput/backend.c b/backend/libinput/backend.c
index d57f129f..a9595df2 100644
--- a/backend/libinput/backend.c
+++ b/backend/libinput/backend.c
@@ -110,9 +110,9 @@ static bool backend_start(struct wlr_backend *wlr_backend) {
 			no_devs = NULL;
 		}
 	}
-	if (!no_devs && backend->wlr_device_lists.length == 0) {
+	if (!no_devs && backend->wlr_device_lists.size == 0) {
 		handle_libinput_readable(libinput_fd, WL_EVENT_READABLE, backend);
-		if (backend->wlr_device_lists.length == 0) {
+		if (backend->wlr_device_lists.size == 0) {
 			wlr_log(WLR_ERROR, "libinput initialization failed, no input devices");
 			wlr_log(WLR_ERROR, "Set WLR_LIBINPUT_NO_DEVICES=1 to suppress this check");
 			return false;
@@ -141,8 +141,8 @@ static void backend_destroy(struct wlr_backend *wlr_backend) {
 	struct wlr_libinput_backend *backend =
 		get_libinput_backend_from_backend(wlr_backend);
 
-	for (size_t i = 0; i < backend->wlr_device_lists.length; i++) {
-		struct wl_list *wlr_devices = backend->wlr_device_lists.items[i];
+	struct wl_list *wlr_devices;
+	wl_array_for_each(wlr_devices, &backend->wlr_device_lists) {
 		struct wlr_input_device *wlr_dev, *next;
 		wl_list_for_each_safe(wlr_dev, next, wlr_devices, link) {
 			wlr_input_device_destroy(wlr_dev);
@@ -156,7 +156,7 @@ static void backend_destroy(struct wlr_backend *wlr_backend) {
 	wl_list_remove(&backend->session_destroy.link);
 	wl_list_remove(&backend->session_signal.link);
 
-	wlr_list_finish(&backend->wlr_device_lists);
+	wl_array_release(&backend->wlr_device_lists);
 	if (backend->input_event) {
 		wl_event_source_remove(backend->input_event);
 	}
@@ -211,10 +211,7 @@ struct wlr_backend *wlr_libinput_backend_create(struct wl_display *display,
 	}
 	wlr_backend_init(&backend->backend, &backend_impl);
 
-	if (!wlr_list_init(&backend->wlr_device_lists)) {
-		wlr_log(WLR_ERROR, "Allocation failed: %s", strerror(errno));
-		goto error_backend;
-	}
+	wl_array_init(&backend->wlr_device_lists);
 
 	backend->session = session;
 	backend->display = display;
@@ -229,9 +226,6 @@ struct wlr_backend *wlr_libinput_backend_create(struct wl_display *display,
 	wl_display_add_destroy_listener(display, &backend->display_destroy);
 
 	return &backend->backend;
-error_backend:
-	free(backend);
-	return NULL;
 }
 
 struct libinput_device *wlr_libinput_get_device_handle(
diff --git a/backend/libinput/events.c b/backend/libinput/events.c
index fa29ef93..e5778bc9 100644
--- a/backend/libinput/events.c
+++ b/backend/libinput/events.c
@@ -7,6 +7,7 @@
 #include <wlr/interfaces/wlr_input_device.h>
 #include <wlr/util/log.h>
 #include "backend/libinput.h"
+#include "util/array.h"
 #include "util/signal.h"
 
 static struct wlr_libinput_input_device *get_libinput_device_from_device(
@@ -183,8 +184,13 @@ static void handle_device_added(struct wlr_libinput_backend *backend,
 	}
 
 	if (!wl_list_empty(wlr_devices)) {
+		struct wl_list **dst = wl_array_add(&backend->wlr_device_lists, sizeof(wlr_devices));
+		if (!dst) {
+			goto fail;
+		}
+		*dst = wlr_devices;
+
 		libinput_device_set_user_data(libinput_dev, wlr_devices);
-		wlr_list_push(&backend->wlr_device_lists, wlr_devices);
 	} else {
 		free(wlr_devices);
 	}
@@ -213,11 +219,15 @@ static void handle_device_removed(struct wlr_libinput_backend *backend,
 	wl_list_for_each_safe(dev, tmp_dev, wlr_devices, link) {
 		wlr_input_device_destroy(dev);
 	}
-	for (size_t i = 0; i < backend->wlr_device_lists.length; i++) {
-		if (backend->wlr_device_lists.items[i] == wlr_devices) {
-			wlr_list_del(&backend->wlr_device_lists, i);
+	size_t i = 0;
+	struct wl_list *iter;
+	wl_array_for_each(iter, &backend->wlr_device_lists) {
+		if (iter == wlr_devices) {
+			array_remove_at(&backend->wlr_device_lists,
+				i * sizeof(struct wl_list *), sizeof(struct wl_list *));
 			break;
 		}
+		i++;
 	}
 	free(wlr_devices);
 }
diff --git a/include/backend/libinput.h b/include/backend/libinput.h
index 3e0b425c..2bfb1421 100644
--- a/include/backend/libinput.h
+++ b/include/backend/libinput.h
@@ -7,7 +7,6 @@
 #include <wlr/backend/libinput.h>
 #include <wlr/interfaces/wlr_input_device.h>
 #include <wlr/types/wlr_input_device.h>
-#include <wlr/types/wlr_list.h>
 
 struct wlr_libinput_backend {
 	struct wlr_backend backend;
@@ -22,7 +21,7 @@ struct wlr_libinput_backend {
 	struct wl_listener session_destroy;
 	struct wl_listener session_signal;
 
-	struct wlr_list wlr_device_lists; // list of struct wl_list
+	struct wl_array wlr_device_lists; // struct wl_list *
 };
 
 struct wlr_libinput_input_device {