Re: [nft PATCH 2/2] src: get rid of printf

[Eric Leblond <eric@regit.org>]

Hi,

On Mon, 2017-09-04 at 00:34 +0200, Pablo Neira Ayuso wrote:
> On Mon, Sep 04, 2017 at 12:03:56AM +0200, Eric Leblond wrote:
> > This patch introduces the nft_print_to_output_ctx function that has
> > to be used instead of printf to output information that where
> > previously send to stdout. This function accumulate the output in
> > a buffer that can be fetched by the user with the
> > nft_ctx_get_output()
> > function.
> > 
> > This modification will allow the libnftables library to provide an
> > easy way to the users to get the output data and display them like
> > they want.
> > 
> > Signed-off-by: Eric Leblond <eric@regit.org>
> > ---
> >  include/datatype.h   |   5 +-
> >  include/expression.h |   2 +-
> >  include/nftables.h   |   5 ++
> >  src/cli.c            |   1 +
> >  src/ct.c             |  21 ++---
> >  src/datatype.c       |  66 ++++++++-------
> >  src/expression.c     |  79 ++++++++++--------
> >  src/exthdr.c         |  16 ++--
> >  src/fib.c            |  23 +++---
> >  src/hash.c           |  10 +--
> >  src/main.c           |  45 ++++++++++
> >  src/meta.c           |  32 +++++---
> >  src/numgen.c         |   8 +-
> >  src/payload.c        |   9 +-
> >  src/rule.c           | 228 +++++++++++++++++++++++++++++--------
> > --------------
> >  src/statement.c      | 145 +++++++++++++++++---------------
> >  16 files changed, 408 insertions(+), 287 deletions(-)
> > 
> > diff --git a/include/datatype.h b/include/datatype.h
> > index 2e34591..e9f6079 100644
> > --- a/include/datatype.h
> > +++ b/include/datatype.h
> > @@ -209,7 +209,8 @@ extern void symbolic_constant_print(const
> > struct symbol_table *tbl,
> >  				    struct output_ctx *octx);
> >  extern void symbol_table_print(const struct symbol_table *tbl,
> >  			       const struct datatype *dtype,
> > -			       enum byteorder byteorder);
> > +			       enum byteorder byteorder,
> > +			       struct output_ctx *octx);
> >  
> >  extern struct symbol_table *rt_symbol_table_init(const char
> > *filename);
> >  extern void rt_symbol_table_free(struct symbol_table *tbl);
> > @@ -261,7 +262,7 @@ extern const struct datatype *
> >  set_datatype_alloc(const struct datatype *orig_dtype, unsigned int
> > byteorder);
> >  extern void set_datatype_destroy(const struct datatype *dtype);
> >  
> > -extern void time_print(uint64_t seconds);
> > +extern void time_print(uint64_t seconds, struct output_ctx *octx);
> >  extern struct error_record *time_parse(const struct location *loc,
> >  				       const char *c, uint64_t
> > *res);
> >  
> > diff --git a/include/expression.h b/include/expression.h
> > index 32d4423..ce6b702 100644
> > --- a/include/expression.h
> > +++ b/include/expression.h
> > @@ -334,7 +334,7 @@ extern struct expr *expr_get(struct expr
> > *expr);
> >  extern void expr_free(struct expr *expr);
> >  extern void expr_print(const struct expr *expr, struct output_ctx
> > *octx);
> >  extern bool expr_cmp(const struct expr *e1, const struct expr
> > *e2);
> > -extern void expr_describe(const struct expr *expr);
> > +extern void expr_describe(const struct expr *expr, struct
> > output_ctx *octx);
> >  
> >  extern const struct datatype *expr_basetype(const struct expr
> > *expr);
> >  extern void expr_set_type(struct expr *expr, const struct datatype
> > *dtype,
> > diff --git a/include/nftables.h b/include/nftables.h
> > index 7c4e93f..f4d5ce1 100644
> > --- a/include/nftables.h
> > +++ b/include/nftables.h
> > @@ -30,6 +30,8 @@ struct output_ctx {
> >  	unsigned int ip2name;
> >  	unsigned int handle;
> >  	unsigned int echo;
> > +	char *output_buf;
> > +	size_t output_buf_len;
> >  };
> >  
> >  struct nft_cache {
> > @@ -149,4 +151,7 @@ void realm_table_meta_exit(void);
> >  void devgroup_table_exit(void);
> >  void realm_table_rt_exit(void);
> >  
> > +int nft_print_to_output_ctx(struct output_ctx *octx, const char
> > *fmt, ...);
> > +char *nft_ctx_get_output(struct nft_ctx *ctx);
> > +
> >  #endif /* NFTABLES_NFTABLES_H */
> > diff --git a/src/cli.c b/src/cli.c
> > index d923ff7..ca4418c 100644
> > --- a/src/cli.c
> > +++ b/src/cli.c
> > @@ -138,6 +138,7 @@ static void cli_complete(char *line)
> >  		    cli_nft->debug_mask);
> >  	scanner_push_buffer(scanner, &indesc_cli, line);
> >  	nft_run(cli_nft, cli_nf_sock, scanner, state, &msgs);
> > +	printf("%s", nft_ctx_get_output(cli_nft));
> >  	erec_print_list(stdout, &msgs, cli_nft->debug_mask);
> >  	xfree(line);
> >  	cache_release(&cli_nft->cache);
> > diff --git a/src/ct.c b/src/ct.c
> > index d64f467..f19608a 100644
> > --- a/src/ct.c
> > +++ b/src/ct.c
> > @@ -141,11 +141,12 @@ static void ct_label_type_print(const struct
> > expr *expr,
> >  	for (s = ct_label_tbl->symbols; s->identifier != NULL;
> > s++) {
> >  		if (bit != s->value)
> >  			continue;
> > -		printf("\"%s\"", s->identifier);
> > +		nft_print_to_output_ctx(octx, "\"%s\"", s-
> > >identifier);
> >  		return;
> >  	}
> >  	/* can happen when connlabel.conf is altered after rules
> > were added */
> > -	printf("%ld\n", (long)mpz_scan1(expr->value, 0));
> > +	nft_print_to_output_ctx(octx, "%ld\n",
> 
> Let's call this nft_print(), ok?

Yes, that's really better.

> 
> I can make the rename here before applying.

No need, I'm gonna resubmit the patchset.

BR,
-- 
Eric Leblond <eric@regit.org>