static ssize_t flush_buf(VirtIOSerialPort *port, const uint8_t *buf, ssize_t len) { VirtConsole *vcon = VIRTIO_CONSOLE(port); ssize_t ret; if (!vcon->chr) { /* If there's no backend, we can just say we consumed all data. */ return len; } ret = qemu_chr_fe_write(vcon->chr, buf, len); trace_virtio_console_flush_buf(port->id, len, ret); if (ret < len) { VirtIOSerialPortClass *k = VIRTIO_SERIAL_PORT_GET_CLASS(port); /* * Ideally we'd get a better error code than just -1, but * that's what the chardev interface gives us right now. If * we had a finer-grained message, like -EPIPE, we could close * this connection. if (ret < 0) ret = 0; if (!k->is_console) { virtio_serial_throttle_port(port, true); if (!vcon->watch) { vcon->watch = qemu_chr_fe_add_watch(vcon->chr, G_IO_OUT|G_IO_HUP, chr_write_unblocked, vcon); } } } return ret; }