From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:47558) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1cPWtD-0005Mm-VM for qemu-devel@nongnu.org; Fri, 06 Jan 2017 10:57:12 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1cPWtA-0005XJ-L8 for qemu-devel@nongnu.org; Fri, 06 Jan 2017 10:57:12 -0500 Received: from mx1.redhat.com ([209.132.183.28]:43492) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1cPWtA-0005Wx-Fx for qemu-devel@nongnu.org; Fri, 06 Jan 2017 10:57:08 -0500 Received: from int-mx11.intmail.prod.int.phx2.redhat.com (int-mx11.intmail.prod.int.phx2.redhat.com [10.5.11.24]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 8EB1C8124A for ; Fri, 6 Jan 2017 15:57:08 +0000 (UTC) From: "Daniel P. Berrange" Date: Fri, 6 Jan 2017 15:55:43 +0000 Message-Id: <20170106155543.12827-48-berrange@redhat.com> In-Reply-To: <20170106155543.12827-1-berrange@redhat.com> References: <20170106155543.12827-1-berrange@redhat.com> Subject: [Qemu-devel] [PATCH v2 47/47] trace: improve error reporting when parsing simpletrace header List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-devel@nongnu.org Cc: Stefan Hajnoczi , "Daniel P. Berrange" When loading a simpletrace binary file we just report "Not a valid trace file!" which is not very helpful. Report exactly which field we found to be invalid. Signed-off-by: Daniel P. Berrange --- scripts/simpletrace.py | 10 +++++++--- 1 file changed, 7 insertions(+), 3 deletions(-) diff --git a/scripts/simpletrace.py b/scripts/simpletrace.py index 4ca903d..4c99004 100755 --- a/scripts/simpletrace.py +++ b/scripts/simpletrace.py @@ -73,10 +73,14 @@ def read_record(edict, idtoname, fobj): def read_trace_header(fobj): """Read and verify trace file header""" header = read_header(fobj, log_header_fmt) - if header is None or \ - header[0] != header_event_id or \ - header[1] != header_magic: + if header is None: raise ValueError('Not a valid trace file!') + if header[0] != header_event_id: + raise ValueError('Not a valid trace file, header id %d != %d' % + (header[0], header_event_id)) + if header[1] != header_magic: + raise ValueError('Not a valid trace file, header magic %d != %d' % + (header[1], header_magic)) log_version = header[2] if log_version not in [0, 2, 3, 4]: -- 2.9.3