[PATCH] dd: implement status=noxfer and status=none

[Ari Sundholm]

This patch (or an equivalent) is required to run some of the tests in
xfstests on busybox. I would really like to see this merged if it is
acceptable.

On Wed, 2014-10-01 at 16:55 +0300, Ari Sundholm wrote:
> This patch is still waiting for comments and review.
> 
> On Wed, 2014-09-24 at 11:33 +0300, Ari Sundholm wrote:
> > Hi!
> > 
> > Any comments on this patch?
> > 
> > The bloat-o-meter results are as follows (provided I managed to use the
> > tool correctly):
> > 
> > function                                             old     new   delta
> > .rodata                                           151082  151119     +37
> > ------------------------------------------------------------------------------
> > (add/remove: 0/0 grow/shrink: 1/0 up/down: 37/0)               Total: 37 bytes
> > 
> > Best regards,
> > Ari Sundholm
> > ari at tuxera.com
> > 
> > On Thu, 2014-09-18 at 16:37 +0300, Ari Sundholm wrote:
> > > From: Ari Sundholm <ari at tuxera.com>
> > > 
> > > Signed-off-by: Ari Sundholm <ari at tuxera.com>
> > > ---
> > >  coreutils/dd.c | 35 +++++++++++++++++++++++++++++++++--
> > >  1 file changed, 33 insertions(+), 2 deletions(-)
> > > 
> > > diff --git a/coreutils/dd.c b/coreutils/dd.c
> > > index 2838f63..f2c7b04 100644
> > > --- a/coreutils/dd.c
> > > +++ b/coreutils/dd.c
> > > @@ -32,6 +32,10 @@
> > >  //usage:     "\n	conv=fsync	Physically write data out before finishing"
> > >  //usage:     "\n	conv=swab	Swap every pair of bytes"
> > >  //usage:	)
> > > +//usage:	IF_FEATURE_DD_THIRD_STATUS_LINE(
> > > +//usage:	 "\n	status=noxfer	Suppress transfer stats"
> > > +//usage:	)
> > > +//usage:	 "\n	status=none	Suppress all output"
> > >  //usage:     "\n"
> > >  //usage:     "\nN may be suffixed by c (1), w (2), b (512), kD (1000), k (1024), MD, M, GD, G"
> > >  //usage:
> > > @@ -69,6 +73,7 @@ struct globals {
> > >  #if ENABLE_FEATURE_DD_THIRD_STATUS_LINE
> > >  	unsigned long long total_bytes;
> > >  	unsigned long long begin_time_us;
> > > +	int noxfer;
> > >  #endif
> > >  } FIX_ALIASING;
> > >  #define G (*(struct globals*)&bb_common_bufsiz1)
> > > @@ -93,6 +98,9 @@ static void dd_output_status(int UNUSED_PARAM cur_signal)
> > >  			G.out_full, G.out_part);
> > >  
> > >  #if ENABLE_FEATURE_DD_THIRD_STATUS_LINE
> > > +	if (G.noxfer)
> > > +		return;
> > > +
> > >  	fprintf(stderr, "%llu bytes (%sB) copied, ",
> > >  			G.total_bytes,
> > >  			/* show fractional digit, use suffixes */
> > > @@ -159,9 +167,12 @@ int dd_main(int argc UNUSED_PARAM, char **argv)
> > >  		/* end of conv flags */
> > >  		FLAG_TWOBUFS = (1 << 5) * ENABLE_FEATURE_DD_IBS_OBS,
> > >  		FLAG_COUNT   = 1 << 6,
> > > +		FLAG_STATUS  = 1 << 7,
> > > +		FLAG_STATUS_NONE = 1 << 7,
> > > +		FLAG_STATUS_NOXFER = (1 << 8) * ENABLE_FEATURE_DD_THIRD_STATUS_LINE,
> > >  	};
> > >  	static const char keywords[] ALIGN1 =
> > > -		"bs\0""count\0""seek\0""skip\0""if\0""of\0"
> > > +		"bs\0""count\0""seek\0""skip\0""if\0""of\0""status\0"
> > >  #if ENABLE_FEATURE_DD_IBS_OBS
> > >  		"ibs\0""obs\0""conv\0"
> > >  #endif
> > > @@ -170,6 +181,12 @@ int dd_main(int argc UNUSED_PARAM, char **argv)
> > >  	static const char conv_words[] ALIGN1 =
> > >  		"notrunc\0""sync\0""noerror\0""fsync\0""swab\0";
> > >  #endif
> > > +	static const char status_words[] ALIGN1 =
> > > +		"none\0"
> > > +#if ENABLE_FEATURE_DD_THIRD_STATUS_LINE
> > > +		"noxfer\0"
> > > +#endif
> > > +		;
> > >  	enum {
> > >  		OP_bs = 0,
> > >  		OP_count,
> > > @@ -177,6 +194,7 @@ int dd_main(int argc UNUSED_PARAM, char **argv)
> > >  		OP_skip,
> > >  		OP_if,
> > >  		OP_of,
> > > +		OP_status,
> > >  #if ENABLE_FEATURE_DD_IBS_OBS
> > >  		OP_ibs,
> > >  		OP_obs,
> > > @@ -314,6 +332,14 @@ int dd_main(int argc UNUSED_PARAM, char **argv)
> > >  			outfile = val;
> > >  			/*continue;*/
> > >  		}
> > > +		if (what == OP_status) {
> > > +			int n;
> > > +			n = index_in_strings(status_words, val);
> > > +			if (n < 0)
> > > +				bb_error_msg_and_die(bb_msg_invalid_arg, val, "status");
> > > +			flags |= FLAG_STATUS << n;
> > > +			/*continue;*/
> > > +		}
> > >  	} /* end of "for (argv[i])" */
> > >  
> > >  //XXX:FIXME for huge ibs or obs, malloc'ing them isn't the brightest idea ever
> > > @@ -468,7 +494,12 @@ int dd_main(int argc UNUSED_PARAM, char **argv)
> > >  
> > >  	exitcode = EXIT_SUCCESS;
> > >   out_status:
> > > -	dd_output_status(0);
> > > +#if ENABLE_FEATURE_DD_THIRD_STATUS_LINE
> > > +	G.noxfer = !!(flags & FLAG_STATUS_NOXFER);
> > > +#endif
> > > +
> > > +	if (!(flags & FLAG_STATUS_NONE))
> > > +		dd_output_status(0);
> > >  
> > >  	if (ENABLE_FEATURE_CLEAN_UP) {
> > >  		free(obuf);
> > 
>