From patchwork Thu Mar 2 03:46:09 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jeff Cody X-Patchwork-Id: 734454 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 3vYdYs3RK5z9s7n for ; Thu, 2 Mar 2017 14:47:45 +1100 (AEDT) Received: from localhost ([::1]:50183 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1cjHiQ-0003yA-VK for incoming@patchwork.ozlabs.org; Wed, 01 Mar 2017 22:47:43 -0500 Received: from eggs.gnu.org ([2001:4830:134:3::10]:46585) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1cjHhA-0003iL-6j for qemu-devel@nongnu.org; Wed, 01 Mar 2017 22:46:25 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1cjHh9-0004Eh-4B for qemu-devel@nongnu.org; Wed, 01 Mar 2017 22:46:24 -0500 Received: from mx1.redhat.com ([209.132.183.28]:47528) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1cjHh3-0004An-6T; Wed, 01 Mar 2017 22:46:17 -0500 Received: from int-mx13.intmail.prod.int.phx2.redhat.com (int-mx13.intmail.prod.int.phx2.redhat.com [10.5.11.26]) (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 50EA380474; Thu, 2 Mar 2017 03:46:17 +0000 (UTC) Received: from localhost (ovpn-116-95.phx2.redhat.com [10.3.116.95]) by int-mx13.intmail.prod.int.phx2.redhat.com (8.14.4/8.14.4) with ESMTP id v223kGcW001488 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=NO); Wed, 1 Mar 2017 22:46:16 -0500 From: Jeff Cody To: qemu-block@nongnu.org Date: Wed, 1 Mar 2017 22:46:09 -0500 Message-Id: <20170302034613.21609-2-jcody@redhat.com> In-Reply-To: <20170302034613.21609-1-jcody@redhat.com> References: <20170302034613.21609-1-jcody@redhat.com> X-Scanned-By: MIMEDefang 2.68 on 10.5.11.26 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.28]); Thu, 02 Mar 2017 03:46:17 +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] [PULL v3 1/5] block/rbd: don't copy strings in qemu_rbd_next_tok() 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: peter.maydell@linaro.org, jcody@redhat.com, qemu-devel@nongnu.org Errors-To: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org Sender: "Qemu-devel" This patch is prep work for parsing options for .bdrv_parse_filename, and using QDict options. The function qemu_rbd_next_tok() searched for various key/value pairs, and copied them into buffers. This will soon be an unnecessary extra step, so we will now return found strings by reference only, and offload the responsibility for safely handling/coping these strings to the caller. This also cleans up error handling some, as the callers now rely on the Error object to determine if there is a parse error. Reviewed-by: Eric Blake Reviewed-by: Markus Armbruster Signed-off-by: Jeff Cody --- block/rbd.c | 99 +++++++++++++++++++++++++++++++++++++++---------------------- 1 file changed, 64 insertions(+), 35 deletions(-) diff --git a/block/rbd.c b/block/rbd.c index 22e8e69..33c21d8 100644 --- a/block/rbd.c +++ b/block/rbd.c @@ -102,10 +102,10 @@ typedef struct BDRVRBDState { char *snap; } BDRVRBDState; -static int qemu_rbd_next_tok(char *dst, int dst_len, - char *src, char delim, - const char *name, - char **p, Error **errp) +static char *qemu_rbd_next_tok(int max_len, + char *src, char delim, + const char *name, + char **p, Error **errp) { int l; char *end; @@ -127,17 +127,15 @@ static int qemu_rbd_next_tok(char *dst, int dst_len, } } l = strlen(src); - if (l >= dst_len) { + if (l >= max_len) { error_setg(errp, "%s too long", name); - return -EINVAL; + return NULL; } else if (l == 0) { error_setg(errp, "%s too short", name); - return -EINVAL; + return NULL; } - pstrcpy(dst, dst_len, src); - - return 0; + return src; } static void qemu_rbd_unescape(char *src) @@ -162,7 +160,9 @@ static int qemu_rbd_parsename(const char *filename, { const char *start; char *p, *buf; - int ret; + int ret = 0; + char *found_str; + Error *local_err = NULL; if (!strstart(filename, "rbd:", &start)) { error_setg(errp, "File name must start with 'rbd:'"); @@ -174,36 +174,60 @@ static int qemu_rbd_parsename(const char *filename, *snap = '\0'; *conf = '\0'; - ret = qemu_rbd_next_tok(pool, pool_len, p, - '/', "pool name", &p, errp); - if (ret < 0 || !p) { + found_str = qemu_rbd_next_tok(pool_len, p, + '/', "pool name", &p, &local_err); + if (local_err) { + goto done; + } + if (!p) { ret = -EINVAL; + error_setg(errp, "Pool name is required"); goto done; } - qemu_rbd_unescape(pool); + qemu_rbd_unescape(found_str); + g_strlcpy(pool, found_str, pool_len); if (strchr(p, '@')) { - ret = qemu_rbd_next_tok(name, name_len, p, - '@', "object name", &p, errp); - if (ret < 0) { + found_str = qemu_rbd_next_tok(name_len, p, + '@', "object name", &p, &local_err); + if (local_err) { goto done; } - ret = qemu_rbd_next_tok(snap, snap_len, p, - ':', "snap name", &p, errp); - qemu_rbd_unescape(snap); + qemu_rbd_unescape(found_str); + g_strlcpy(name, found_str, name_len); + + found_str = qemu_rbd_next_tok(snap_len, p, + ':', "snap name", &p, &local_err); + if (local_err) { + goto done; + } + qemu_rbd_unescape(found_str); + g_strlcpy(snap, found_str, snap_len); } else { - ret = qemu_rbd_next_tok(name, name_len, p, - ':', "object name", &p, errp); + found_str = qemu_rbd_next_tok(name_len, p, + ':', "object name", &p, &local_err); + if (local_err) { + goto done; + } + qemu_rbd_unescape(found_str); + g_strlcpy(name, found_str, name_len); } - qemu_rbd_unescape(name); - if (ret < 0 || !p) { + if (!p) { goto done; } - ret = qemu_rbd_next_tok(conf, conf_len, p, - '\0', "configuration", &p, errp); + found_str = qemu_rbd_next_tok(conf_len, p, + '\0', "configuration", &p, &local_err); + if (local_err) { + goto done; + } + g_strlcpy(conf, found_str, conf_len); done: + if (local_err) { + ret = -EINVAL; + error_propagate(errp, local_err); + } g_free(buf); return ret; } @@ -262,17 +286,18 @@ static int qemu_rbd_set_conf(rados_t cluster, const char *conf, Error **errp) { char *p, *buf; - char name[RBD_MAX_CONF_NAME_SIZE]; - char value[RBD_MAX_CONF_VAL_SIZE]; + char *name; + char *value; + Error *local_err = NULL; int ret = 0; buf = g_strdup(conf); p = buf; while (p) { - ret = qemu_rbd_next_tok(name, sizeof(name), p, - '=', "conf option name", &p, errp); - if (ret < 0) { + name = qemu_rbd_next_tok(RBD_MAX_CONF_NAME_SIZE, p, + '=', "conf option name", &p, &local_err); + if (local_err) { break; } qemu_rbd_unescape(name); @@ -283,9 +308,9 @@ static int qemu_rbd_set_conf(rados_t cluster, const char *conf, break; } - ret = qemu_rbd_next_tok(value, sizeof(value), p, - ':', "conf option value", &p, errp); - if (ret < 0) { + value = qemu_rbd_next_tok(RBD_MAX_CONF_VAL_SIZE, p, + ':', "conf option value", &p, &local_err); + if (local_err) { break; } qemu_rbd_unescape(value); @@ -313,6 +338,10 @@ static int qemu_rbd_set_conf(rados_t cluster, const char *conf, } } + if (local_err) { + error_propagate(errp, local_err); + ret = -EINVAL; + } g_free(buf); return ret; }