swaybar: allow identifiers for output and tray

This allows `bar output` and `bar tray_output` to specify an output
identifier. Output names should still work as well.

This parses the output identifier from the xdg_output description,
which wlroots currently sets to `make model serial (name)`. Since this
could change in the future, all identifier comparisons are guarded by
NULL-checks in case the description cannot be parsed to an identifier.

2 files changed, 30 insertions, 8 deletions

diff --git a/swaybar/bar.c b/swaybar/bar.c
index 7aed4dca..d36367fc 100644
--- a/swaybar/bar.c
+++ b/swaybar/bar.c
@@ -59,6 +59,7 @@ static void swaybar_output_free(struct swaybar_output *output) {
         free_workspaces(&output->workspaces);
         wl_list_remove(&output->link);
         free(output->name);
+        free(output->identifier);
         free(output);
 }
 
@@ -166,13 +167,15 @@ bool determine_bar_visibility(struct swaybar *bar, bool moving_layer) {
         return visible;
 }
 
-static bool bar_uses_output(struct swaybar *bar, const char *name) {
-        if (bar->config->all_outputs) {
+static bool bar_uses_output(struct swaybar_output *output) {
+        if (output->bar->config->all_outputs) {
                 return true;
         }
+        char *identifier = output->identifier;
         struct config_output *coutput;
-        wl_list_for_each(coutput, &bar->config->outputs, link) {
-                if (strcmp(coutput->name, name) == 0) {
+        wl_list_for_each(coutput, &output->bar->config->outputs, link) {
+                if (strcmp(coutput->name, output->name) == 0 ||
+                                (identifier && strcmp(coutput->name, identifier) == 0)) {
                         return true;
                 }
         }
@@ -233,7 +236,7 @@ static void xdg_output_handle_done(void *data,
         struct swaybar *bar = output->bar;
 
         assert(output->name != NULL);
-        if (!bar_uses_output(bar, output->name)) {
+        if (!bar_uses_output(output)) {
                 swaybar_output_free(output);
                 return;
         }
@@ -258,7 +261,22 @@ static void xdg_output_handle_name(void *data,
 
 static void xdg_output_handle_description(void *data,
                 struct zxdg_output_v1 *xdg_output, const char *description) {
-        // Who cares
+        // wlroots currently sets the description to `make model serial (name)`
+        // If this changes in the future, this will need to be modified.
+        struct swaybar_output *output = data;
+        free(output->identifier);
+        output->identifier = NULL;
+        char *paren = strrchr(description, '(');
+        if (paren) {
+                size_t length = paren - description;
+                output->identifier = malloc(length);
+                if (!output->identifier) {
+                        wlr_log(WLR_ERROR, "Failed to allocate output identifier");
+                        return;
+                }
+                strncpy(output->identifier, description, length);
+                output->identifier[length - 1] = '\0';
+        }
 }
 
 struct zxdg_output_v1_listener xdg_output_listener = {
diff --git a/swaybar/tray/tray.c b/swaybar/tray/tray.c
index 0c3517cb..d5d0c84e 100644
--- a/swaybar/tray/tray.c
+++ b/swaybar/tray/tray.c
@@ -101,13 +101,17 @@ void tray_in(int fd, short mask, void *data) {
 }
 
 static int cmp_output(const void *item, const void *cmp_to) {
-        return strcmp(item, cmp_to);
+        const struct swaybar_output *output = cmp_to;
+        if (output->identifier && strcmp(item, output->identifier) == 0) {
+                return 0;
+        }
+        return strcmp(item, output->name);
 }
 
 uint32_t render_tray(cairo_t *cairo, struct swaybar_output *output, double *x) {
         struct swaybar_config *config = output->bar->config;
         if (config->tray_outputs) {
-                if (list_seq_find(config->tray_outputs, cmp_output, output->name) == -1) {
+                if (list_seq_find(config->tray_outputs, cmp_output, output) == -1) {
                         return 0;
                 }
         } // else display on all