ESP_EVENT_LOG_SZ
esp->esp_event_cur = (idx + 1) & (ESP_EVENT_LOG_SZ - 1);
esp->esp_event_cur = (idx + 1) & (ESP_EVENT_LOG_SZ - 1);
idx = (idx + 1) & (ESP_EVENT_LOG_SZ - 1);
struct esp_event_ent esp_event_log[ESP_EVENT_LOG_SZ];