swaybar: explicitly check return value of getdelim

This prevents an signed-to-unsigned conversion error on buffer_index if
getdelim fails and returns -1, which caused swaybar to try to search the
header for the array and immediately failing

1 files changed, 7 insertions, 3 deletions

diff --git a/swaybar/status_line.c b/swaybar/status_line.c
index 401bf6f6..48b43248 100644
--- a/swaybar/status_line.c
+++ b/swaybar/status_line.c
@@ -67,9 +67,13 @@ bool status_handle_readable(struct status_line *status) {
 
                         wl_list_init(&status->blocks);
                         status->tokener = json_tokener_new();
-                        status->buffer_index = getdelim(&status->buffer,
-                                        &status->buffer_size, EOF, status->read);
-                        return i3bar_handle_readable(status);
+                        read_bytes = getdelim(&status->buffer, &status->buffer_size, EOF, status->read);
+                        if (read_bytes > 0) {
+                                status->buffer_index = read_bytes;
+                                return i3bar_handle_readable(status);
+                        } else {
+                                return false;
+                        }
                 }
 
                 wlr_log(WLR_DEBUG, "Using text protocol.");