Allow multiple outputs for workspace output

`i3 4.16` allows users to list multiple outputs for a workspace and the
first available will be used. The syntax is as follows:
`workspace <workspace> output <outputs...>`

Additionally when the workspace is created, the outputs get added to the
output priority list in the order specified. This ensures that if a higher
output gets connected, the workspace will move to the higher output. This
works the same way as if the user had a workspace on an output, disconnected
the output, and then later reconnected the output.

1 files changed, 44 insertions, 17 deletions

diff --git a/sway/tree/workspace.c b/sway/tree/workspace.c
index 93ce50de..4be63311 100644
--- a/sway/tree/workspace.c
+++ b/sway/tree/workspace.c
@@ -33,14 +33,15 @@ struct workspace_config *workspace_find_config(const char *ws_name) {
 struct sway_output *workspace_get_initial_output(const char *name) {
         // Check workspace configs for a workspace<->output pair
         struct workspace_config *wsc = workspace_find_config(name);
-        if (wsc && wsc->output) {
-                struct sway_output *output = output_by_name(wsc->output);
-                if (!output) {
-                        output = output_by_identifier(wsc->output);
-                }
-                
-                if (output) {
-                        return output;
+        if (wsc) {
+                for (int i = 0; i < wsc->outputs->length; i++) {
+                        struct sway_output *output = output_by_name(wsc->outputs->items[i]);
+                        if (!output) {
+                                output = output_by_identifier(wsc->outputs->items[i]);
+                        }
+                        if (output) {
+                                return output;
+                        }
                 }
         }
         // Otherwise put it on the focused output
@@ -85,7 +86,6 @@ struct sway_workspace *workspace_create(struct sway_output *output,
         ws->floating = create_list();
         ws->tiling = create_list();
         ws->output_priority = create_list();
-        workspace_output_add_priority(ws, output);
 
         ws->gaps_outer = config->gaps_outer;
         ws->gaps_inner = config->gaps_inner;
@@ -110,9 +110,17 @@ struct sway_workspace *workspace_create(struct sway_output *output,
                         // Since default outer gaps can be smaller than the negation of
                         // workspace specific inner gaps, check outer gaps again
                         prevent_invalid_outer_gaps(ws);
+
+                        // Add output priorities
+                        for (int i = 0; i < wsc->outputs->length; ++i) {
+                                list_add(ws->output_priority, strdup(wsc->outputs->items[i]));
+                        }
                 }
         }
 
+        // If not already added, add the output to the lowest priority
+        workspace_output_add_priority(ws, output);
+
         output_add_workspace(output, ws);
         output_sort_workspaces(output);
 
@@ -134,8 +142,7 @@ void workspace_destroy(struct sway_workspace *workspace) {
 
         free(workspace->name);
         free(workspace->representation);
-        list_foreach(workspace->output_priority, free);
-        list_free(workspace->output_priority);
+        free_flat_list(workspace->output_priority);
         list_free(workspace->floating);
         list_free(workspace->tiling);
         list_free(workspace->current.floating);
@@ -177,8 +184,19 @@ static bool workspace_valid_on_output(const char *output_name,
         char identifier[128];
         struct sway_output *output = output_by_name(output_name);
         output_get_identifier(identifier, sizeof(identifier), output);
-                
-        return !wsc || !wsc->output || strcmp(wsc->output, output_name) == 0 || strcasecmp(identifier, output_name) == 0;
+
+        if (!wsc) {
+                return true;
+        }
+
+        for (int i = 0; i < wsc->outputs->length; i++) {
+                if (strcmp(wsc->outputs->items[i], output_name) == 0 ||
+                                strcmp(wsc->outputs->items[i], identifier) == 0) {
+                        return true;
+                }
+        }
+
+        return false;
 }
 
 static void workspace_name_from_binding(const struct sway_binding * binding,
@@ -281,10 +299,19 @@ char *workspace_next_name(const char *output_name) {
         for (int i = 0; i < config->workspace_configs->length; ++i) {
                 // Unlike with bindings, this does not guarantee order
                 const struct workspace_config *wsc = config->workspace_configs->items[i];
-                if (wsc->output && strcmp(wsc->output, output_name) == 0
-                                && workspace_by_name(wsc->workspace) == NULL) {
-                        free(target);
-                        target = strdup(wsc->workspace);
+                if (workspace_by_name(wsc->workspace)) {
+                        continue;
+                }
+                bool found = false;
+                for (int j = 0; j < wsc->outputs->length; ++j) {
+                        if (strcmp(wsc->outputs->items[j], output_name) == 0) {
+                                found = true;
+                                free(target);
+                                target = strdup(wsc->workspace);
+                                break;
+                        }
+                }
+                if (found) {
                         break;
                 }
         }