Handle NULL from output_get_active_workspace

This modifies the places where output_get_active_workspace is called to
handle a NULL result. Some places already handled it and did not need a
change, some just have guard off code blocks, others return errors, and
some have sway_asserts since the case should never happen. A lot of this
is probably just safety precautions since they probably will never be
called when `output_get_active_workspace` is not fully configured with a
workspace.

10 files changed, 50 insertions, 3 deletions

diff --git a/sway/commands/focus.c b/sway/commands/focus.c
index 79b2f551..25df5130 100644
--- a/sway/commands/focus.c
+++ b/sway/commands/focus.c
@@ -37,6 +37,9 @@ static struct sway_node *get_node_in_output_direction(
                 struct sway_output *output, enum wlr_direction dir) {
         struct sway_seat *seat = config->handler_context.seat;
         struct sway_workspace *ws = output_get_active_workspace(output);
+        if (!sway_assert(ws, "Expected output to have a workspace")) {
+                return NULL;
+        }
         if (ws->fullscreen) {
                 return seat_get_focus_inactive(seat, &ws->fullscreen->node);
         }
diff --git a/sway/commands/move.c b/sway/commands/move.c
index 16f8cdb6..d4fb9022 100644
--- a/sway/commands/move.c
+++ b/sway/commands/move.c
@@ -283,6 +283,9 @@ static bool container_move_in_direction(struct sway_container *container,
                         return false;
                 }
                 struct sway_workspace *ws = output_get_active_workspace(new_output);
+                if (!sway_assert(ws, "Expected output to have a workspace")) {
+                        return false;
+                }
                 container_move_to_workspace(container, ws);
                 return true;
         }
@@ -360,6 +363,9 @@ static bool container_move_in_direction(struct sway_container *container,
                 output_get_in_direction(container->workspace->output, move_dir);
         if (output) {
                 struct sway_workspace *ws = output_get_active_workspace(output);
+                if (!sway_assert(ws, "Expected output to have a workspace")) {
+                        return false;
+                }
                 container_move_to_workspace_from_direction(container, ws, move_dir);
                 return true;
         }
@@ -525,6 +531,10 @@ static struct cmd_results *cmd_move_container(int argc, char **argv) {
         case N_OUTPUT: {
                         struct sway_output *output = destination->sway_output;
                         struct sway_workspace *ws = output_get_active_workspace(output);
+                        if (!sway_assert(ws, "Expected output to have a workspace")) {
+                                return cmd_results_new(CMD_FAILURE,
+                                                "Expected output to have a workspace");
+                        }
                         container_move_to_workspace(container, ws);
                 }
                 break;
@@ -538,7 +548,11 @@ static struct cmd_results *cmd_move_container(int argc, char **argv) {
         // restore focus on destination output back to its last active workspace
         struct sway_workspace *new_workspace =
                 output_get_active_workspace(new_output);
-        if (new_output_last_ws && new_output_last_ws != new_workspace) {
+        if (!sway_assert(new_workspace, "Expected output to have a workspace")) {
+                return cmd_results_new(CMD_FAILURE,
+                                "Expected output to have a workspace");
+        }
+        if (new_output_last_ws != new_workspace) {
                 struct sway_node *new_output_last_focus =
                         seat_get_focus_inactive(seat, &new_output_last_ws->node);
                 seat_set_raw_focus(seat, new_output_last_focus);
@@ -585,6 +599,9 @@ static void workspace_move_to_output(struct sway_workspace *workspace,
         workspace_detach(workspace);
         struct sway_workspace *new_output_old_ws =
                 output_get_active_workspace(output);
+        if (!sway_assert(new_output_old_ws, "Expected output to have a workspace")) {
+                return;
+        }
 
         output_add_workspace(output, workspace);
 
diff --git a/sway/commands/sticky.c b/sway/commands/sticky.c
index 5b70199c..9df1fe09 100644
--- a/sway/commands/sticky.c
+++ b/sway/commands/sticky.c
@@ -9,6 +9,7 @@
 #include "sway/tree/view.h"
 #include "sway/tree/workspace.h"
 #include "list.h"
+#include "log.h"
 #include "util.h"
 
 struct cmd_results *cmd_sticky(int argc, char **argv) {
@@ -29,6 +30,11 @@ struct cmd_results *cmd_sticky(int argc, char **argv) {
                 // move container to active workspace
                 struct sway_workspace *active_workspace =
                         output_get_active_workspace(container->workspace->output);
+                if (!sway_assert(active_workspace,
+                                        "Expected output to have a workspace")) {
+                        return cmd_results_new(CMD_FAILURE,
+                                        "Expected output to have a workspace");
+                }
                 if (container->workspace != active_workspace) {
                         struct sway_workspace *old_workspace = container->workspace;
                         container_detach(container);
diff --git a/sway/commands/swap.c b/sway/commands/swap.c
index 0e2c2d10..b978af16 100644
--- a/sway/commands/swap.c
+++ b/sway/commands/swap.c
@@ -118,6 +118,10 @@ static void container_swap(struct sway_container *con1,
                 output_get_active_workspace(con1->workspace->output);
         struct sway_workspace *vis2 =
                 output_get_active_workspace(con2->workspace->output);
+        if (!sway_assert(vis1 && vis2, "con1 or con2 are on an output without a"
+                                "workspace. This should not happen")) {
+                return;
+        }
 
         char *stored_prev_name = NULL;
         if (seat->prev_workspace_name) {
diff --git a/sway/commands/titlebar_border_thickness.c b/sway/commands/titlebar_border_thickness.c
index 3c5e9ba1..7c27c163 100644
--- a/sway/commands/titlebar_border_thickness.c
+++ b/sway/commands/titlebar_border_thickness.c
@@ -21,7 +21,12 @@ struct cmd_results *cmd_titlebar_border_thickness(int argc, char **argv) {
 
         for (int i = 0; i < root->outputs->length; ++i) {
                 struct sway_output *output = root->outputs->items[i];
-                arrange_workspace(output_get_active_workspace(output));
+                struct sway_workspace *ws = output_get_active_workspace(output);
+                if (!sway_assert(ws, "Expected output to have a workspace")) {
+                        return cmd_results_new(CMD_FAILURE,
+                                        "Expected output to have a workspace");
+                }
+                arrange_workspace(ws);
                 output_damage_whole(output);
         }
 
diff --git a/sway/desktop/output.c b/sway/desktop/output.c
index 61beb7af..d7d3fc07 100644
--- a/sway/desktop/output.c
+++ b/sway/desktop/output.c
@@ -251,6 +251,9 @@ static void output_for_each_surface(struct sway_output *output,
         };
 
         struct sway_workspace *workspace = output_get_active_workspace(output);
+        if (!workspace) {
+                return;
+        }
         struct sway_container *fullscreen_con = root->fullscreen_global;
         if (fullscreen_con && container_is_scratchpad_hidden(fullscreen_con)) {
                 fullscreen_con = NULL;
diff --git a/sway/input/cursor.c b/sway/input/cursor.c
index 170532be..3236c74a 100644
--- a/sway/input/cursor.c
+++ b/sway/input/cursor.c
@@ -104,6 +104,9 @@ struct sway_node *node_at_coords(
 
         // find the focused workspace on the output for this seat
         struct sway_workspace *ws = output_get_active_workspace(output);
+        if (!ws) {
+                return NULL;
+        }
 
         if ((*surface = layer_surface_at(output,
                                 &output->layers[ZWLR_LAYER_SHELL_V1_LAYER_OVERLAY],
diff --git a/sway/ipc-json.c b/sway/ipc-json.c
index 6d36c727..a2ab2bba 100644
--- a/sway/ipc-json.c
+++ b/sway/ipc-json.c
@@ -198,6 +198,9 @@ static void ipc_json_describe_output(struct sway_output *output,
                         ipc_json_output_transform_description(wlr_output->transform)));
 
         struct sway_workspace *ws = output_get_active_workspace(output);
+        if (!sway_assert(ws, "Expected output to have a workspace")) {
+                return;
+        }
         json_object_object_add(object, "current_workspace",
                         json_object_new_string(ws->name));
 
diff --git a/sway/tree/container.c b/sway/tree/container.c
index 9358dad7..933907f4 100644
--- a/sway/tree/container.c
+++ b/sway/tree/container.c
@@ -831,7 +831,7 @@ void container_floating_move_to(struct sway_container *con,
         }
         struct sway_workspace *new_workspace =
                 output_get_active_workspace(new_output);
-        if (old_workspace != new_workspace) {
+        if (new_workspace && old_workspace != new_workspace) {
                 container_detach(con);
                 workspace_add_floating(new_workspace, con);
                 arrange_workspace(old_workspace);
diff --git a/sway/tree/output.c b/sway/tree/output.c
index 146bc423..e0a66e0b 100644
--- a/sway/tree/output.c
+++ b/sway/tree/output.c
@@ -143,6 +143,9 @@ void output_enable(struct sway_output *output, struct output_config *oc) {
 static void evacuate_sticky(struct sway_workspace *old_ws,
                 struct sway_output *new_output) {
         struct sway_workspace *new_ws = output_get_active_workspace(new_output);
+        if (!sway_assert(new_ws, "New output does not have a workspace")) {
+                return;
+        }
         while (old_ws->floating->length) {
                 struct sway_container *sticky = old_ws->floating->items[0];
                 container_detach(sticky);