Fix scratchpad fullscreen behavior and crash

When setting fullscreen on a hidden scratchpad container, there was a
check to see if there was an existing fullscreen container on the
workspace so it could be fullscreen disabled first. Since the workspace
is NULL, it would cause a SIGSEGV. This adds a NULL check to avoid the
crash.

This also changes the behavior of how fullscreen is handled when adding
a container to the scratchpad or changing visibility of a scratchpad
container to match i3's. The behavior is as follows:
- When adding a container to the scratchpad or hiding a container back
  into the scratchpad, there is an implicit fullscreen disable
- When setting fullscreen on a container that is hidden in the
  scratchpad, it will be fullscreen when shown (and fullscreen disabled
  when hidden as stated above)
- When setting fullscreen global on a container that is hidden in the
  scratchpad, it will be shown immediately as fullscreen global. The
  container is not moved to a workspace and remains in the
  scratchpad. The container will be visible until fullscreen disabled
  or killed. Since the container is in the scratchpad, running
  `scratchpad show` or `move container to scratchpad` will have no
  effect

This also changes `container_replace` to transfer fullscreen and
scratchpad status.

6 files changed, 32 insertions, 2 deletions

diff --git a/sway/commands/floating.c b/sway/commands/floating.c
index 5df9b1bf..ce123345 100644
--- a/sway/commands/floating.c
+++ b/sway/commands/floating.c
@@ -32,6 +32,11 @@ struct cmd_results *cmd_floating(int argc, char **argv) {
                 seat_set_focus_container(config->handler_context.seat, container);
         }
 
+        if (container_is_scratchpad_hidden(container)) {
+                return cmd_results_new(CMD_INVALID,
+                                "Can't change floating on hidden scratchpad container");
+        }
+
         // If the container is in a floating split container,
         // operate on the split container instead of the child.
         if (container_is_floating_or_child(container)) {
diff --git a/sway/commands/focus.c b/sway/commands/focus.c
index 14e90955..8baa616d 100644
--- a/sway/commands/focus.c
+++ b/sway/commands/focus.c
@@ -182,6 +182,10 @@ static struct sway_node *node_get_in_direction_floating(
         double closest_distance = DBL_MAX;
         struct sway_container *closest_con = NULL;
 
+        if (!con->workspace) {
+                return NULL;
+        }
+
         for (int i = 0; i < con->workspace->floating->length; i++) {
                 struct sway_container *floater = con->workspace->floating->items[i];
                 if (floater == con) {
diff --git a/sway/commands/fullscreen.c b/sway/commands/fullscreen.c
index 52248ce4..a268ba03 100644
--- a/sway/commands/fullscreen.c
+++ b/sway/commands/fullscreen.c
@@ -26,6 +26,13 @@ struct cmd_results *cmd_fullscreen(int argc, char **argv) {
                                 "Can't fullscreen an empty workspace");
         }
 
+        // If in the scratchpad, operate on the highest container
+        if (container && !container->workspace) {
+                while (container->parent) {
+                        container = container->parent;
+                }
+        }
+
         bool is_fullscreen = container &&
                 container->fullscreen_mode != FULLSCREEN_NONE;
         bool global = false;
diff --git a/sway/commands/layout.c b/sway/commands/layout.c
index 7d61c3be..32f8fb52 100644
--- a/sway/commands/layout.c
+++ b/sway/commands/layout.c
@@ -147,7 +147,11 @@ struct cmd_results *cmd_layout(int argc, char **argv) {
                         workspace->layout = new_layout;
                         workspace_update_representation(workspace);
                 }
-                arrange_workspace(workspace);
+                if (root->fullscreen_global) {
+                        arrange_root();
+                } else {
+                        arrange_workspace(workspace);
+                }
         }
 
         return cmd_results_new(CMD_SUCCESS, NULL);
diff --git a/sway/commands/move.c b/sway/commands/move.c
index f642f023..4ebc949b 100644
--- a/sway/commands/move.c
+++ b/sway/commands/move.c
@@ -395,6 +395,11 @@ static struct cmd_results *cmd_move_container(int argc, char **argv) {
                 container = workspace_wrap_children(workspace);
         }
 
+        if (container->fullscreen_mode == FULLSCREEN_GLOBAL) {
+                return cmd_results_new(CMD_FAILURE,
+                                "Can't move fullscreen global container");
+        }
+
         bool no_auto_back_and_forth = false;
         while (strcasecmp(argv[0], "--no-auto-back-and-forth") == 0) {
                 no_auto_back_and_forth = true;
@@ -646,6 +651,10 @@ static struct cmd_results *cmd_move_workspace(int argc, char **argv) {
         }
 
         struct sway_workspace *workspace = config->handler_context.workspace;
+        if (!workspace) {
+                return cmd_results_new(CMD_FAILURE, "No workspace to move");
+        }
+
         struct sway_output *old_output = workspace->output;
         int center_x = workspace->width / 2 + workspace->x,
                 center_y = workspace->height / 2 + workspace->y;
diff --git a/sway/commands/split.c b/sway/commands/split.c
index e9670722..8702f39e 100644
--- a/sway/commands/split.c
+++ b/sway/commands/split.c
@@ -13,7 +13,8 @@ static struct cmd_results *do_split(int layout) {
         struct sway_container *con = config->handler_context.container;
         struct sway_workspace *ws = config->handler_context.workspace;
         if (con) {
-                if (container_is_scratchpad_hidden(con)) {
+                if (container_is_scratchpad_hidden(con) &&
+                                con->fullscreen_mode != FULLSCREEN_GLOBAL) {
                         return cmd_results_new(CMD_FAILURE,
                                         "Cannot split a hidden scratchpad container");
                 }