Surface lock解析

status_t Surface::lock(
        ANativeWindow_Buffer* outBuffer, ARect* inOutDirtyBounds)
{

    ANativeWindowBuffer* out;
    int fenceFd = -1;
    status_t err = dequeueBuffer(&out, &fenceFd);


   outBuffer->width  = backBuffer->width;
            outBuffer->height = backBuffer->height;
            outBuffer->stride = backBuffer->stride;
            outBuffer->format = backBuffer->format;
            outBuffer->bits   = vaddr;

}

首先需要出队一个buffer ，

将外部传入的outBuffer的 bits 设置为vaddr ，也就是buffer的 地址 ，外部可以直接往这里写入数据。