From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from aserp1040.oracle.com ([141.146.126.69]:23487 "EHLO aserp1040.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751230AbdGPTyX (ORCPT ); Sun, 16 Jul 2017 15:54:23 -0400 Date: Sun, 16 Jul 2017 12:54:15 -0700 From: "Darrick J. Wong" Subject: [PATCH v2] xfs_db: redirect printfs when metadumping to stdout Message-ID: <20170716195415.GE4224@magnolia> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Sender: linux-xfs-owner@vger.kernel.org List-ID: List-Id: xfs To: Eric Sandeen Cc: xfs , David Shaw If we're metadumping to stdout, we don't want xfs_db's various dbprintf statements dumping to stdout because that'll corrupt the metadump. Therefore, let outf point to the existing stdout and redirect stdout to stderr for the duration of the dump operation. Reported-by: David Shaw Signed-off-by: Darrick J. Wong --- v2: Better comments. --- db/metadump.c | 15 +++++++++++++-- 1 file changed, 13 insertions(+), 2 deletions(-) diff --git a/db/metadump.c b/db/metadump.c index e046f60..b58acef 100644 --- a/db/metadump.c +++ b/db/metadump.c @@ -2874,6 +2874,7 @@ metadump_f( xfs_agnumber_t agno; int c; int start_iocur_sp; + bool stdout_metadump = false; char *p; exitcode = 1; @@ -2988,7 +2989,15 @@ metadump_f( free(metablock); return 0; } + /* + * Redirect stdout to stderr for the duration of the + * metadump operation so that dbprintf and other messages + * are sent to the console instead of polluting the + * metadump stream. + */ outf = stdout; + stdout = stderr; + stdout_metadump = true; } else { outf = fopen(argv[optind], "wb"); if (outf == NULL) { @@ -3020,9 +3029,11 @@ metadump_f( exitcode = write_index() < 0; if (progress_since_warning) - fputc('\n', (outf == stdout) ? stderr : stdout); + fputc('\n', stdout_metadump ? stderr : stdout); - if (outf != stdout) + if (stdout_metadump) + stdout = outf; + else fclose(outf); /* cleanup iocur stack */