swaybar/bg: Fix crash on DPMS off

When turning off displays via DPMS, swaybar and swaybg still tried to
render, but did not get a valid buffer, causing them to crash.

1 files changed, 3 insertions, 0 deletions

diff --git a/swaybg/main.c b/swaybg/main.c
index 1796b245..f8e7e7ef 100644
--- a/swaybg/main.c
+++ b/swaybg/main.c
@@ -68,6 +68,9 @@ static void render_frame(struct swaybg_state *state) {
                 buffer_height = state->height * state->scale;
         state->current_buffer = get_next_buffer(state->shm,
                         state->buffers, buffer_width, buffer_height);
+        if (!state->current_buffer) {
+                return;
+        }
         cairo_t *cairo = state->current_buffer->cairo;
         if (state->args->mode == BACKGROUND_MODE_SOLID_COLOR) {
                 cairo_set_source_u32(cairo, state->context.color);