add scroll button option

This commit introduces a scroll_button option, which is intended to be
used with scroll_method. Now user can edit his sway config and add an
scroll_button option to device section.

1 files changed, 31 insertions, 0 deletions

diff --git a/sway/commands/input/scroll_button.c b/sway/commands/input/scroll_button.c
new file mode 100644
index 00000000..a9d697cf
--- /dev/null
+++ b/sway/commands/input/scroll_button.c
@@ -0,0 +1,31 @@
+#include <string.h>
+#include <strings.h>
+#include "sway/config.h"
+#include "sway/commands.h"
+#include "sway/input/input-manager.h"
+
+struct cmd_results *input_cmd_scroll_button(int argc, char **argv) {
+	struct cmd_results *error = NULL;
+	if ((error = checkarg(argc, "scroll_button", EXPECTED_AT_LEAST, 1))) {
+		return error;
+	}
+	struct input_config *current_input_config =
+		config->handler_context.input_config;
+	if (!current_input_config) {
+		return cmd_results_new(CMD_FAILURE, "scroll_button",
+			"No input device defined.");
+	}
+	struct input_config *new_config =
+		new_input_config(current_input_config->identifier);
+
+	int scroll_button = atoi(argv[0]);
+	if (scroll_button < 1 || scroll_button > 10) {
+		free_input_config(new_config);
+		return cmd_results_new(CMD_INVALID, "scroll_button",
+				"Input out of range [1, 10]");
+	}
+	new_config->scroll_button = scroll_button;
+
+	apply_input_config(new_config);
+	return cmd_results_new(CMD_SUCCESS, NULL, NULL);
+}