From patchwork Thu Feb 11 18:31:14 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Kevin Wolf X-Patchwork-Id: 12083851 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-13.6 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 30CC9C433DB for ; Thu, 11 Feb 2021 18:36:49 +0000 (UTC) Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id BEEED64E15 for ; Thu, 11 Feb 2021 18:36:48 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org BEEED64E15 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Received: from localhost ([::1]:57454 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1lAGpb-0000zX-Qv for qemu-devel@archiver.kernel.org; Thu, 11 Feb 2021 13:36:47 -0500 Received: from eggs.gnu.org ([2001:470:142:3::10]:41518) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1lAGlN-0003r2-TT for qemu-devel@nongnu.org; Thu, 11 Feb 2021 13:32:26 -0500 Received: from us-smtp-delivery-124.mimecast.com ([63.128.21.124]:28623) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_CBC_SHA1:256) (Exim 4.90_1) (envelope-from ) id 1lAGlG-0002Yh-VA for qemu-devel@nongnu.org; Thu, 11 Feb 2021 13:32:25 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1613068338; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=OEXr/KFAvHBwjAPUs5Het4HRC1PIKOoI7BKoe9KiT7k=; b=P6GwDwSZAZUjKVsdAQZWCdUTu8SPkXZeqezkUDj7tq90P5ITt5tZYVQhDKUFGKqV+awof4 3dHzkVzzzX2qVpuH/FRV6h7FEJNQmnWcPaQ0Y478lud3dGfZ+XCmOL2PZu7/4alZ2tRxiu jekPgB2hNwPVGryaC4u4uQfixZukMGA= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-186-4K2O79jYNuq7drbFdzxuVA-1; Thu, 11 Feb 2021 13:32:15 -0500 X-MC-Unique: 4K2O79jYNuq7drbFdzxuVA-1 Received: from smtp.corp.redhat.com (int-mx06.intmail.prod.int.phx2.redhat.com [10.5.11.16]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 627CF814738 for ; Thu, 11 Feb 2021 18:31:33 +0000 (UTC) Received: from merkur.fritz.box (ovpn-113-82.ams2.redhat.com [10.36.113.82]) by smtp.corp.redhat.com (Postfix) with ESMTP id 6AFDD5C260; Thu, 11 Feb 2021 18:31:31 +0000 (UTC) From: Kevin Wolf To: qemu-devel@nongnu.org Subject: [PATCH v2 2/6] qapi: Remember alias definitions in qobject-input-visitor Date: Thu, 11 Feb 2021 19:31:14 +0100 Message-Id: <20210211183118.422036-3-kwolf@redhat.com> In-Reply-To: <20210211183118.422036-1-kwolf@redhat.com> References: <20210211183118.422036-1-kwolf@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.16 Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=CUSA124A263 smtp.mailfrom=kwolf@redhat.com X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Received-SPF: pass client-ip=63.128.21.124; envelope-from=kwolf@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -33 X-Spam_score: -3.4 X-Spam_bar: --- X-Spam_report: (-3.4 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.569, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_LOW=-0.7, RCVD_IN_MSPIKE_H4=0.001, RCVD_IN_MSPIKE_WL=0.001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: kwolf@redhat.com, jsnow@redhat.com, armbru@redhat.com Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" This makes qobject-input-visitor remember the currently valid aliases in each StackObject. It doesn't actually allow using the aliases yet. Signed-off-by: Kevin Wolf --- qapi/qobject-input-visitor.c | 145 +++++++++++++++++++++++++++++++++++ 1 file changed, 145 insertions(+) diff --git a/qapi/qobject-input-visitor.c b/qapi/qobject-input-visitor.c index 23843b242e..aa95cd49bd 100644 --- a/qapi/qobject-input-visitor.c +++ b/qapi/qobject-input-visitor.c @@ -29,6 +29,50 @@ #include "qemu/cutils.h" #include "qemu/option.h" +/* + * Describes an alias that is relevant for the current StackObject, + * either because it aliases a member of the currently visited object + * or because it aliases a member of a nested object. + * + * When processing a nested object, all InputVisitorAlias objects that + * are relevant for the nested object are propagated, i.e. copied with + * the name of the nested object removed from @source. + */ +typedef struct InputVisitorAlias { + /* StackObject in which the alias was defined */ + struct StackObject *alias_so; + + /* + * Alias name as defined for @alias_so. + * NULL means that this is a wildcard alias, i.e. all members of + * @src get an alias in @alias_so with the same name. + */ + const char *name; + + /* + * NULL terminated array representing a path to the source member + * that the alias refers to. + * + * Must contain at least one non-NULL element if @alias is not NULL. + * + * If it contains no non-NULL element, @alias_so must be different + * from the StackObject which contains this InputVisitorAlias in + * its aliases list. In this case, all elements in the currently + * visited object have an alias with the same name in @alias_so. + */ + const char **src; + + /* + * The alias remains valid as long as the StackObject which + * contains this InputVisitorAlias in its aliases list has + * StackObject.alias_scope_nesting >= InputVisitorAlias.scope_nesting + * or until the whole StackObject is removed. + */ + int scope_nesting; + + QSLIST_ENTRY(InputVisitorAlias) next; +} InputVisitorAlias; + typedef struct StackObject { const char *name; /* Name of @obj in its parent, if any */ QObject *obj; /* QDict or QList being visited */ @@ -38,6 +82,9 @@ typedef struct StackObject { const QListEntry *entry; /* If @obj is QList: unvisited tail */ unsigned index; /* If @obj is QList: list index of @entry */ + QSLIST_HEAD(, InputVisitorAlias) aliases; + int alias_scope_nesting; /* Number of open alias scopes */ + QSLIST_ENTRY(StackObject) node; /* parent */ } StackObject; @@ -203,6 +250,43 @@ static const char *qobject_input_get_keyval(QObjectInputVisitor *qiv, return qstring_get_str(qstr); } +/* + * Propagate aliases from the parent StackObject @src to its direct + * child StackObject @dst, which is representing the child struct @name. + * + * Every alias whose source path begins with @dst->name and which still + * applies in @dst (i.e. it is either a wildcard alias or has at least + * one more source path element) is propagated to @dst with the first + * element (i.e. @dst->name) removed from the source path. + */ +static void propagate_aliases(StackObject *dst, StackObject *src) +{ + InputVisitorAlias *a; + + QSLIST_FOREACH(a, &src->aliases, next) { + if (!a->src[0] || strcmp(a->src[0], dst->name)) { + continue; + } + + /* + * If this is not a wildcard alias, but a->src[1] is NULL, + * then it referred to dst->name in src and doesn't apply + * inside dst any more. + */ + if (a->src[1] || !a->name) { + InputVisitorAlias *alias = g_new(InputVisitorAlias, 1); + + *alias = (InputVisitorAlias) { + .name = a->name, + .alias_so = a->alias_so, + .src = &a->src[1], + }; + + QSLIST_INSERT_HEAD(&dst->aliases, alias, next); + } + } +} + static const QListEntry *qobject_input_push(QObjectInputVisitor *qiv, const char *name, QObject *obj, void *qapi) @@ -226,6 +310,9 @@ static const QListEntry *qobject_input_push(QObjectInputVisitor *qiv, g_hash_table_insert(h, (void *)qdict_entry_key(entry), NULL); } tos->h = h; + if (!QSLIST_EMPTY(&qiv->stack)) { + propagate_aliases(tos, QSLIST_FIRST(&qiv->stack)); + } } else { assert(qlist); tos->entry = qlist_first(qlist); @@ -257,10 +344,17 @@ static bool qobject_input_check_struct(Visitor *v, Error **errp) static void qobject_input_stack_object_free(StackObject *tos) { + InputVisitorAlias *a; + if (tos->h) { g_hash_table_unref(tos->h); } + while ((a = QSLIST_FIRST(&tos->aliases))) { + QSLIST_REMOVE_HEAD(&tos->aliases, next); + g_free(a); + } + g_free(tos); } @@ -274,6 +368,54 @@ static void qobject_input_pop(Visitor *v, void **obj) qobject_input_stack_object_free(tos); } +static void qobject_input_start_alias_scope(Visitor *v) +{ + QObjectInputVisitor *qiv = to_qiv(v); + StackObject *tos = QSLIST_FIRST(&qiv->stack); + + tos->alias_scope_nesting++; +} + +static void qobject_input_end_alias_scope(Visitor *v) +{ + QObjectInputVisitor *qiv = to_qiv(v); + StackObject *tos = QSLIST_FIRST(&qiv->stack); + InputVisitorAlias *a, *next; + + assert(tos->alias_scope_nesting > 0); + tos->alias_scope_nesting--; + + QSLIST_FOREACH_SAFE(a, &tos->aliases, next, next) { + if (a->scope_nesting > tos->alias_scope_nesting) { + QSLIST_REMOVE(&tos->aliases, a, InputVisitorAlias, next); + g_free(a); + } + } +} + +static void qobject_input_define_alias(Visitor *v, const char *name, + const char **source) +{ + QObjectInputVisitor *qiv = to_qiv(v); + StackObject *tos = QSLIST_FIRST(&qiv->stack); + InputVisitorAlias *alias = g_new(InputVisitorAlias, 1); + + /* + * The source path can become empty during alias propagation for + * wildcard aliases, but not when defining an alias (it would map + * all names onto themselves, which doesn't make sense). + */ + assert(source[0]); + + *alias = (InputVisitorAlias) { + .name = name, + .alias_so = tos, + .src = source, + }; + + QSLIST_INSERT_HEAD(&tos->aliases, alias, next); +} + static bool qobject_input_start_struct(Visitor *v, const char *name, void **obj, size_t size, Error **errp) { @@ -696,6 +838,9 @@ static QObjectInputVisitor *qobject_input_visitor_base_new(QObject *obj) v->visitor.end_list = qobject_input_end_list; v->visitor.start_alternate = qobject_input_start_alternate; v->visitor.optional = qobject_input_optional; + v->visitor.define_alias = qobject_input_define_alias; + v->visitor.start_alias_scope = qobject_input_start_alias_scope; + v->visitor.end_alias_scope = qobject_input_end_alias_scope; v->visitor.free = qobject_input_free; v->root = qobject_ref(obj);