Re: [Tarantool-patches] [PATCH luajit v2 2/7] core: introduce write buffer module

[Sergey Kaplun <skaplun@tarantool.org>]

Hi!

Thanks for the review!

On 26.12.20, Sergey Ostanevich wrote:
> Hi! 
> 
> Thanks for the patch!
> 
> Just one problem and LGTM otherwise.
> 
> Sergos
> 
> > --- a/src/lj_wbuf.h
> > +++ b/src/lj_wbuf.h
> > @@ -31,32 +31,32 @@
> > #define STREAM_ERR_IO 0x1
> > #define STREAM_STOP   0x2
> > 
> > +/*
> > +** Buffer writer which is called on the buffer flush.
> > +** Should return amount of written bytes on success or zero in case of error.
> > +** *data should contain a buffer of at least the initial size.
> 
> Does it mean the writer’s provider should preserve the ‘initial size’ is some way?

Yes, inside `ctx`, for example.

> Should it create two or more buffers of the same size during initialization?

If necessary, but it is not required. This is the user's responsibility.

> 
> > +** If *data == NULL stream stops.
> > +*/
> > typedef size_t (*lj_wbuf_writer)(const void **data, size_t len, void *opt);
> > 
> > /* Write buffer. */
> > struct lj_wbuf {
> > -  /*
> > -  ** Buffer writer which will called at buffer write.
> > -  ** Should return amount of written bytes on success or zero in case of error.
> > -  ** *data should contain new buffer of size greater or equal to len.
> > -  ** If *data == NULL stream stops.
> > -  */
> >   lj_wbuf_writer writer;
> >   /* Context for writer function. */
> >   void *ctx;
> >   /* Buffer size. */
> >   size_t size;
> > -  /* Saved errno in case of error. */
> > -  int saved_errno;
> >   /* Start of buffer. */
> >   uint8_t *buf;
> >   /* Current position in buffer. */
> >   uint8_t *pos;
> > +  /* Saved errno in case of error. */
> > +  int saved_errno;
> >   /* Internal flags. */
> >   volatile uint8_t flags;
> > };
> > 
> > -/* Init buffer. */
> > +/* Initialize the buffer. */
> > void lj_wbuf_init(struct lj_wbuf *buf, lj_wbuf_writer writer, void *ctx,
> > 		  uint8_t *mem, size_t size);
> > 
> > ===================================================================
> > 
> > -- 
> > Best regards,
> > Sergey Kaplun
> 

-- 
Best regards,
Sergey Kaplun