Merge pull request #1835 from ascent12/swaybar_status_err

Swaybar fix

2 files changed, 38 insertions, 22 deletions

diff --git a/swaybar/bar.c b/swaybar/bar.c
index d51c4ec7..669cb11a 100644
--- a/swaybar/bar.c
+++ b/swaybar/bar.c
@@ -401,24 +401,28 @@ void bar_setup(struct swaybar *bar,
         render_all_frames(bar);
 }
 
-static void display_in(int fd, short mask, void *_bar) {
-        struct swaybar *bar = (struct swaybar *)_bar;
+static void display_in(int fd, short mask, void *data) {
+        struct swaybar *bar = data;
         if (wl_display_dispatch(bar->display) == -1) {
                 bar_teardown(bar);
                 exit(0);
         }
 }
 
-static void ipc_in(int fd, short mask, void *_bar) {
-        struct swaybar *bar = (struct swaybar *)_bar;
+static void ipc_in(int fd, short mask, void *data) {
+        struct swaybar *bar = data;
         if (handle_ipc_readable(bar)) {
                 render_all_frames(bar);
         }
 }
 
-static void status_in(int fd, short mask, void *_bar) {
-        struct swaybar *bar = (struct swaybar *)_bar;
-        if (status_handle_readable(bar->status)) {
+static void status_in(int fd, short mask, void *data) {
+        struct swaybar *bar = data;
+        if (mask & (POLLHUP | POLLERR)) {
+                status_error(bar->status, "[error reading from status command]");
+                render_all_frames(bar);
+                remove_event(fd);
+        } else if (status_handle_readable(bar->status)) {
                 render_all_frames(bar);
         }
 }
diff --git a/swaybar/event_loop.c b/swaybar/event_loop.c
index 748372ed..bc4053be 100644
--- a/swaybar/event_loop.c
+++ b/swaybar/event_loop.c
@@ -72,24 +72,18 @@ void add_event(int fd, short mask,
 }
 
 bool remove_event(int fd) {
-        int index = -1;
+        /*
+         * Instead of removing events immediately, we mark them for deletion
+         * and clean them up later. This is so we can call remove_event inside
+         * an event callback safely.
+         */
         for (int i = 0; i < event_loop.fds.length; ++i) {
                 if (event_loop.fds.items[i].fd == fd) {
-                        index = i;
+                        event_loop.fds.items[i].fd = -1;
+                        return true;
                 }
         }
-        if (index != -1) {
-                free(event_loop.items->items[index]);
-
-                --event_loop.fds.length;
-                memmove(&event_loop.fds.items[index], &event_loop.fds.items[index + 1],
-                                sizeof(struct pollfd) * event_loop.fds.length - index);
-
-                list_del(event_loop.items, index);
-                return true;
-        } else {
-                return false;
-        }
+        return false;
 }
 
 static int timer_item_timer_cmp(const void *_timer_item, const void *_timer) {
@@ -118,11 +112,29 @@ void event_loop_poll() {
                 struct pollfd pfd = event_loop.fds.items[i];
                 struct event_item *item = (struct event_item *)event_loop.items->items[i];
 
-                if (pfd.revents & pfd.events) {
+                // Always send these events
+                unsigned events = pfd.events | POLLHUP | POLLERR;
+
+                if (pfd.revents & events) {
                         item->cb(pfd.fd, pfd.revents, item->data);
                 }
         }
 
+        // Cleanup removed events
+        int end = 0;
+        int length = event_loop.fds.length;
+        for (int i = 0; i < length; ++i) {
+                if (event_loop.fds.items[i].fd == -1) {
+                        free(event_loop.items->items[i]);
+                        list_del(event_loop.items, i);
+                        --event_loop.fds.length;
+                } else if (end != i) {
+                        event_loop.fds.items[end++] = event_loop.fds.items[i];
+                } else {
+                        end = i + 1;
+                }
+        }
+
         // check timers
         // not tested, but seems to work
         for (int i = 0; i < event_loop.timers->length; ++i) {