Only mark a window if only one window is matched

We only support unique marks, so looping over all matched windows must be prevented.
If more than one window is matched, we reject it with an error message.

fixes #1614

diff --git a/src/commands.c b/src/commands.c
index dc60e974f796ad4b244c15d5a8b427be211f53af..79071d6bb5f451dbae214fcb6fd2a53dbde7813f 100644 (file)
--- a/src/commands.c
+++ b/src/commands.c
@@ -1043,32 +1043,34 @@ void cmd_workspace_name(I3_CMD, char *name) {
 void cmd_mark(I3_CMD, char *mark, char *toggle) {
     HANDLE_EMPTY_MATCH;
 
-    owindow *current;
-    TAILQ_FOREACH(current, &owindows, owindows) {
-        DLOG("matching: %p / %s\n", current->con, current->con->name);
-        current->con->mark_changed = true;
-        if (toggle != NULL && current->con->mark && strcmp(current->con->mark, mark) == 0) {
-            DLOG("removing window mark %s\n", mark);
-            FREE(current->con->mark);
-        } else {
-            DLOG("marking window with str %s\n", mark);
-            FREE(current->con->mark);
-            current->con->mark = sstrdup(mark);
-        }
+    owindow *current = TAILQ_FIRST(&owindows);
+    if (current == NULL) {
+        ysuccess(false);
+        return;
+    }
+
+    /* Marks must be unique, i.e., no two windows must have the same mark. */
+    if (current != TAILQ_LAST(&owindows, owindows_head)) {
+        yerror("A mark must not be put onto more than one window");
+        return;
+    }
+
+    DLOG("matching: %p / %s\n", current->con, current->con->name);
+    current->con->mark_changed = true;
+    if (toggle != NULL && current->con->mark && strcmp(current->con->mark, mark) == 0) {
+        DLOG("removing window mark %s\n", mark);
+        FREE(current->con->mark);
+    } else {
+        DLOG("marking window with str %s\n", mark);
+        FREE(current->con->mark);
+        current->con->mark = sstrdup(mark);
     }
 
     DLOG("Clearing all non-matched windows with this mark\n");
     Con *con;
     TAILQ_FOREACH(con, &all_cons, all_cons) {
-        /* Skip matched windows, we took care of them already. */
-        bool matched = false;
-        TAILQ_FOREACH(current, &owindows, owindows) {
-            if (current->con == con) {
-                matched = true;
-                break;
-            }
-        }
-        if (matched)
+        /* Skip matched window, we took care of it already. */
+        if (current->con == con)
             continue;
 
         if (con->mark && strcmp(con->mark, mark) == 0) {