Re: [PATCH 02/12] net: add function to pretty print IPv4

[Stephen Hemminger <stephen@networkplumber.org>]

On Wed, 15 Dec 2021 01:06:14 +0000
"Ananyev, Konstantin" <konstantin.ananyev@intel.com> wrote:

> > -----Original Message-----
> > From: Morten Brørup <mb@smartsharesystems.com>
> > Sent: Tuesday, December 14, 2021 5:31 PM
> > To: Randles, Ronan <ronan.randles@intel.com>; dev@dpdk.org
> > Cc: Van Haaren, Harry <harry.van.haaren@intel.com>
> > Subject: RE: [PATCH 02/12] net: add function to pretty print IPv4
> >   
> > > From: Ronan Randles [mailto:ronan.randles@intel.com]
> > > Sent: Tuesday, 14 December 2021 15.13
> > >
> > > This function accepts an uint32_t representation of an IP address and
> > > produces a string representation stored in a char * buffer. Realavent
> > > unit tests also included.
> > >
> > > Signed-off-by: Ronan Randles <ronan.randles@intel.com>  
> > 
> > [snip]
> >   
> > > diff --git a/lib/net/rte_ip.h b/lib/net/rte_ip.h
> > > index 188054fda4..e46f0b41ba 100644
> > > --- a/lib/net/rte_ip.h
> > > +++ b/lib/net/rte_ip.h
> > > @@ -444,6 +444,26 @@ __rte_experimental
> > >  int32_t
> > >  rte_ip_parse_addr(const char *src_ip, uint32_t *output_addr);
> > >
> > > +
> > > +/**
> > > + * Print IP address from 32 bit int into char * buffer.
> > > + *
> > > + * @param ip_addr
> > > + *   ip address to be printed.
> > > + * @param buffer
> > > + *   The buffer the string will be saved into.
> > > + * @param buffer_size
> > > + *   size of buffer to be used.
> > > + *
> > > + * @retval 0
> > > + *   Success.
> > > + * @retval -1
> > > + *   Failure due to invalid input arguments.
> > > + */
> > > +__rte_experimental
> > > +int32_t
> > > +rte_ip_print_addr(uint32_t ip_addr, char *buffer, uint32_t
> > > buffer_size);
> > > +  
> > 
> > In continuation of my email reply about the IPv4 parse function...
> > 
> > I have a few suggestions to the IPv4 print function too:
> > 
> > The return value should be the number of characters written to the output string, and still -1 on error. With this modification, you could
> > use the return type ssize_t instead of int32_t.
> > 
> > Furthermore, I would prefer having the parameters in the same order as snprintf(): char *str, size_t size, const uint32_t ip_addr. Please
> > also notice the suggested changed type for the size, and the const added to the ip_addr.
> >   
> Honestly, I don't understand why we need to introduce such functions
> inside DPDK at all.
> What's wrong with existing standard ones: inet_ntop() and inet_pton()?

Agreed, I see no added value in reinventing here