recognize dock windows (and support matching them)

src/match.c

@@ -14,6 +14,17 @@
 
 #include "all.h"
 
+/*
+ * Initializes the Match data structure. This function is necessary because the
+ * members representing boolean values (like dock) need to be initialized with
+ * -1 instead of 0.
+ *
+ */
+void match_init(Match *match) {
+    memset(match, 0, sizeof(Match));
+    match->dock = -1;
+}
+
 /*
  * Check if a match is empty. This is necessary while parsing commands to see
  * whether the user specified a match at all.
@@ -30,6 +41,7 @@ bool match_is_empty(Match *match) {
             match->instance == NULL &&
             match->id == XCB_NONE &&
             match->con_id == NULL &&
+            match->dock == -1 &&
             match->floating == M_ANY);
 }
 
@@ -54,6 +66,12 @@ bool match_matches_window(Match *match, i3Window *window) {
         return true;
     }
 
+    LOG("match->dock = %d, window->dock = %d\n", match->dock, window->dock);
+    if (match->dock != -1 && window->dock == match->dock) {
+        LOG("match made by dock\n");
+        return true;
+    }
+
     LOG("window %d (%s) could not be matched\n", window->id, window->class_class);
 
     return false;