standards/177742: conflict of dd's bs= option with use of conv=sparse

[Konstantin Belousov]

The following reply was made to PR standards/177742; it has been noted by GNATS.

From: Konstantin Belousov <kostikbel at gmail.com>
To: Matthew Rezny <mrezny at hexaneinc.com>
Cc: bug-followup at FreeBSD.org
Subject: Re: standards/177742: conflict of dd's bs= option with use of
 conv=sparse
Date: Tue, 23 Apr 2013 09:21:23 +0300

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 On Thu, Apr 11, 2013 at 05:44:59AM +0200, Matthew Rezny wrote:
 > Looking not just at my problem but the overall situation, it seems the
 > logic in dd_in() does not hold up. The last line, (*cfunc)();, actually
 > invokes the appropriate conversion(s) and then calls dd_out(0). With
 > the simple test on line 361, we will never get down to that call if bs=3D
 > option is used. Really, to make the code fit the comment, it should
 > probably be something like
 > if ((ddflags & ~(C_NOERROR | C_NOTRUNC | C_SYNC)) =3D=3D C_BS) {
 >     out.dbcnt =3D in.dbcnt;
 >     dd_out(0);
 >     in.dbcnt =3D 0;
 >     continue;
 > }
 I do not see why did you changed dd_out(1) to dd_out(0).
 
 Anyway, I am going to commit the following patch, unless I get some
 objection in two-three days:
 
 commit 37664b1393db30d97aa9eefa70360cd550bf9dd9
 Author: Konstantin Belousov <kib at freebsd.org>
 Date:   Tue Apr 23 09:18:31 2013 +0300
 
     Literally follow POSIX:
     If the bs=3D expr operand is specified and no conversions other than sy=
 nc,
     noerror, or notrunc are requested, the data returned from each input
     block shall be written as a separate output block.
    =20
     PR:	standards/177742
     Submitted by:	Matthew Rezny <mrezny at hexaneinc.com>
 
 diff --git a/bin/dd/dd.c b/bin/dd/dd.c
 index 01b66fc..9d0f9b1 100644
 --- a/bin/dd/dd.c
 +++ b/bin/dd/dd.c
 @@ -358,7 +358,7 @@ dd_in(void)
  		 * than noerror, notrunc or sync are specified, the block
  		 * is output without buffering as it is read.
  		 */
 -		if (ddflags & C_BS) {
 +		if ((ddflags & ~(C_NOERROR | C_NOTRUNC | C_SYNC)) =3D=3D C_BS) {
  			out.dbcnt =3D in.dbcnt;
  			dd_out(1);
  			in.dbcnt =3D 0;
 
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