From patchwork Mon Jan 16 20:48:47 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Max Reitz X-Patchwork-Id: 715911 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Received: from lists.gnu.org (lists.gnu.org [IPv6:2001:4830:134:3::11]) (using TLSv1 with cipher AES256-SHA (256/256 bits)) (No client certificate requested) by ozlabs.org (Postfix) with ESMTPS id 3v2QTN1N2Nz9s3T for ; Tue, 17 Jan 2017 07:54:32 +1100 (AEDT) Received: from localhost ([::1]:59481 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1cTEIP-000582-LP for incoming@patchwork.ozlabs.org; Mon, 16 Jan 2017 15:54:29 -0500 Received: from eggs.gnu.org ([2001:4830:134:3::10]:45478) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1cTEDL-0000WU-38 for qemu-devel@nongnu.org; Mon, 16 Jan 2017 15:49:16 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1cTEDK-0003gV-7v for qemu-devel@nongnu.org; Mon, 16 Jan 2017 15:49:15 -0500 Received: from mx1.redhat.com ([209.132.183.28]:50366) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1cTEDF-0003fc-Kb; Mon, 16 Jan 2017 15:49:09 -0500 Received: from int-mx10.intmail.prod.int.phx2.redhat.com (int-mx10.intmail.prod.int.phx2.redhat.com [10.5.11.23]) (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 B013F37EEB; Mon, 16 Jan 2017 20:49:09 +0000 (UTC) Received: from localhost (ovpn-204-161.brq.redhat.com [10.40.204.161]) by int-mx10.intmail.prod.int.phx2.redhat.com (8.14.4/8.14.4) with ESMTP id v0GKn76I026286 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=NO); Mon, 16 Jan 2017 15:49:09 -0500 From: Max Reitz To: qemu-block@nongnu.org Date: Mon, 16 Jan 2017 21:48:47 +0100 Message-Id: <20170116204905.31347-1-mreitz@redhat.com> In-Reply-To: <20170111181432.18868-1-mreitz@redhat.com> References: <20170111181432.18868-1-mreitz@redhat.com> X-Scanned-By: MIMEDefang 2.68 on 10.5.11.23 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.29]); Mon, 16 Jan 2017 20:49:09 +0000 (UTC) X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] [fuzzy] X-Received-From: 209.132.183.28 Subject: [Qemu-devel] [PATCH v4 07/25] block: bdrv_get_full_backing_filename's ret. val. X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Kevin Wolf , Alberto Garcia , qemu-devel@nongnu.org, Max Reitz Errors-To: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org Sender: "Qemu-devel" Make bdrv_get_full_backing_filename() return an allocated string instead of placing the result in a caller-provided buffer. Signed-off-by: Max Reitz Reviewed-by: Eric Blake --- include/block/block.h | 3 +-- block.c | 26 +++++++++----------------- block/qapi.c | 12 ++---------- 3 files changed, 12 insertions(+), 29 deletions(-) diff --git a/include/block/block.h b/include/block/block.h index fe16e45aba..eb41956bf1 100644 --- a/include/block/block.h +++ b/include/block/block.h @@ -435,8 +435,7 @@ void bdrv_round_to_clusters(BlockDriverState *bs, const char *bdrv_get_encrypted_filename(BlockDriverState *bs); void bdrv_get_backing_filename(BlockDriverState *bs, char *filename, int filename_size); -void bdrv_get_full_backing_filename(BlockDriverState *bs, - char *dest, size_t sz, Error **errp); +char *bdrv_get_full_backing_filename(BlockDriverState *bs, Error **errp); char *bdrv_get_full_backing_filename_from_filename(const char *backed, const char *backing, Error **errp); diff --git a/block.c b/block.c index b02e492653..7e60bb090b 100644 --- a/block.c +++ b/block.c @@ -220,19 +220,13 @@ char *bdrv_get_full_backing_filename_from_filename(const char *backed, } } -void bdrv_get_full_backing_filename(BlockDriverState *bs, char *dest, size_t sz, - Error **errp) +char *bdrv_get_full_backing_filename(BlockDriverState *bs, Error **errp) { char *backed = bs->exact_filename[0] ? bs->exact_filename : bs->filename; - char *full_name; - full_name = bdrv_get_full_backing_filename_from_filename(backed, - bs->backing_file, - errp); - if (full_name) { - pstrcpy(dest, sz, full_name); - g_free(full_name); - } + return bdrv_get_full_backing_filename_from_filename(backed, + bs->backing_file, + errp); } void bdrv_register(BlockDriver *bdrv) @@ -1484,7 +1478,7 @@ out: int bdrv_open_backing_file(BlockDriverState *bs, QDict *parent_options, const char *bdref_key, Error **errp) { - char *backing_filename = g_malloc0(PATH_MAX); + char *backing_filename = NULL; char *bdref_key_dot; const char *reference = NULL; int ret = 0; @@ -1511,7 +1505,7 @@ int bdrv_open_backing_file(BlockDriverState *bs, QDict *parent_options, reference = qdict_get_try_str(parent_options, bdref_key); if (reference || qdict_haskey(options, "file.filename")) { - backing_filename[0] = '\0'; + /* keep backing_filename NULL */ /* FIXME: Should also be set to true if @options contains other runtime * options which control the data that is read from the backing @@ -1521,8 +1515,7 @@ int bdrv_open_backing_file(BlockDriverState *bs, QDict *parent_options, QDECREF(options); goto free_exit; } else { - bdrv_get_full_backing_filename(bs, backing_filename, PATH_MAX, - &local_err); + backing_filename = bdrv_get_full_backing_filename(bs, &local_err); if (local_err) { ret = -EINVAL; error_propagate(errp, local_err); @@ -1542,9 +1535,8 @@ int bdrv_open_backing_file(BlockDriverState *bs, QDict *parent_options, qdict_put(options, "driver", qstring_from_str(bs->backing_format)); } - backing_hd = bdrv_open_inherit(*backing_filename ? backing_filename : NULL, - reference, options, 0, bs, &child_backing, - errp); + backing_hd = bdrv_open_inherit(backing_filename, reference, options, 0, bs, + &child_backing, errp); if (!backing_hd) { bs->open_flags |= BDRV_O_NO_BACKING; error_prepend(errp, "Could not open backing file: "); diff --git a/block/qapi.c b/block/qapi.c index a62e862f3c..1543dd691a 100644 --- a/block/qapi.c +++ b/block/qapi.c @@ -265,18 +265,10 @@ void bdrv_query_image_info(BlockDriverState *bs, backing_filename = bs->backing_file; if (backing_filename[0] != '\0') { - char *backing_filename2 = g_malloc0(PATH_MAX); + char *backing_filename2; info->backing_filename = g_strdup(backing_filename); info->has_backing_filename = true; - bdrv_get_full_backing_filename(bs, backing_filename2, PATH_MAX, &err); - if (err) { - /* Can't reconstruct the full backing filename, so we must omit - * this field and apply a Best Effort to this query. */ - g_free(backing_filename2); - backing_filename2 = NULL; - error_free(err); - err = NULL; - } + backing_filename2 = bdrv_get_full_backing_filename(bs, NULL); /* Always report the full_backing_filename if present, even if it's the * same as backing_filename. That they are same is useful info. */