Impliment i3-style marks

This commit adds three commands to sway: `show_marks`, `mark` and
`unmark`. Marks are displayed right-aligned in the window border as i3
does. Marks may be found using criteria.

Fixes #1007

1 files changed, 31 insertions, 0 deletions

diff --git a/sway/commands/unmark.c b/sway/commands/unmark.c
new file mode 100644
index 00000000..34a2ae44
--- /dev/null
+++ b/sway/commands/unmark.c
@@ -0,0 +1,31 @@
+#include <string.h>
+#include <strings.h>
+#include "sway/commands.h"
+#include "list.h"
+#include "stringop.h"
+
+struct cmd_results *cmd_unmark(int argc, char **argv) {
+        swayc_t *view = get_focused_container(&root_container);
+
+        if (view->marks) {
+                if (argc) {
+                        char *mark = join_args(argv, argc);
+                        int index;
+                        if ((index = list_seq_find(view->marks, (int (*)(const void *, const void *))strcmp, mark)) != -1) {
+                                free(view->marks->items[index]);
+                                list_del(view->marks, index);
+
+                                if (view->marks->length == 0) {
+                                        list_free(view->marks);
+                                        view->marks = NULL;
+                                }
+                        }
+                        free(mark);
+                } else {
+                        list_foreach(view->marks, free);
+                        list_free(view->marks);
+                        view->marks = NULL;
+                }
+        }
+        return cmd_results_new(CMD_SUCCESS, NULL, NULL);
+}