From patchwork Thu Apr 28 21:45:09 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Eric Blake X-Patchwork-Id: 8975311 Return-Path: X-Original-To: patchwork-qemu-devel@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork1.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.136]) by patchwork1.web.kernel.org (Postfix) with ESMTP id 9E36E9F39D for ; Thu, 28 Apr 2016 21:50:12 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 843C2201F4 for ; Thu, 28 Apr 2016 21:50:11 +0000 (UTC) Received: from lists.gnu.org (lists.gnu.org [208.118.235.17]) (using TLSv1 with cipher AES256-SHA (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 3916820220 for ; Thu, 28 Apr 2016 21:50:10 +0000 (UTC) Received: from localhost ([::1]:51189 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1avtp3-0000GZ-Dg for patchwork-qemu-devel@patchwork.kernel.org; Thu, 28 Apr 2016 17:50:09 -0400 Received: from eggs.gnu.org ([2001:4830:134:3::10]:54921) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1avtkg-0007i1-DE for qemu-devel@nongnu.org; Thu, 28 Apr 2016 17:45:40 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1avtkd-0000AU-QX for qemu-devel@nongnu.org; Thu, 28 Apr 2016 17:45:38 -0400 Received: from mx1.redhat.com ([209.132.183.28]:47294) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1avtkd-00009w-IF for qemu-devel@nongnu.org; Thu, 28 Apr 2016 17:45:35 -0400 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 31F083DD47; Thu, 28 Apr 2016 21:45:35 +0000 (UTC) Received: from red.redhat.com (ovpn-113-21.phx2.redhat.com [10.3.113.21]) by int-mx13.intmail.prod.int.phx2.redhat.com (8.14.4/8.14.4) with ESMTP id u3SLjY8N019512; Thu, 28 Apr 2016 17:45:34 -0400 From: Eric Blake To: qemu-devel@nongnu.org Date: Thu, 28 Apr 2016 15:45:09 -0600 Message-Id: <1461879932-9020-2-git-send-email-eblake@redhat.com> In-Reply-To: <1461879932-9020-1-git-send-email-eblake@redhat.com> References: <1461879932-9020-1-git-send-email-eblake@redhat.com> X-Scanned-By: MIMEDefang 2.68 on 10.5.11.26 X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] X-Received-From: 209.132.183.28 Subject: [Qemu-devel] [PATCH v16 01/24] qapi-visit: Add visitor.type classification 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: armbru@redhat.com, Michael Roth Errors-To: qemu-devel-bounces+patchwork-qemu-devel=patchwork.kernel.org@nongnu.org Sender: "Qemu-devel" X-Spam-Status: No, score=-6.9 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_HI, UNPARSEABLE_RELAY autolearn=unavailable version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP We have three classes of QAPI visitors: input, output, and dealloc. Currently, all implementations of these visitors have one thing in common based on their visitor type: the implementation used for the visit_type_enum() callback. But since we plan to add more such common behavior, in relation to documenting and further refining the semantics, it makes more sense to have the visitor implementations advertise which class they belong to, so the common qapi-visit-core code can use that information in multiple places. A later patch will better document the types of visitors directly in visitor.h. For this patch, knowing the class of a visitor implementation lets us make input_type_enum() and output_type_enum() become static functions, by replacing the callback function Visitor.type_enum() with the simpler enum member Visitor.type. Share a common assertion in qapi-visit-core as part of the refactoring. Move comments in opts-visitor.c to match the refactored layout. Signed-off-by: Eric Blake --- v15: comment improvements v14: no change v13: no change v12: new patch --- include/qapi/visitor.h | 11 +++++++++++ include/qapi/visitor-impl.h | 23 ++++++++++++++--------- qapi/qapi-visit-core.c | 28 +++++++++++++++------------- qapi/opts-visitor.c | 17 +++++++---------- qapi/qapi-dealloc-visitor.c | 7 +------ qapi/qmp-input-visitor.c | 2 +- qapi/qmp-output-visitor.c | 2 +- qapi/string-input-visitor.c | 2 +- qapi/string-output-visitor.c | 2 +- 9 files changed, 52 insertions(+), 42 deletions(-) diff --git a/include/qapi/visitor.h b/include/qapi/visitor.h index 9a8d010..690589f 100644 --- a/include/qapi/visitor.h +++ b/include/qapi/visitor.h @@ -78,8 +78,19 @@ void visit_end_alternate(Visitor *v); */ bool visit_optional(Visitor *v, const char *name, bool *present); +/* + * Visit an enum value. + * + * @strings expresses the mapping between C enum values and QAPI enum + * names; it should be the ENUM_lookup array from visit-types.h. + * + * May call visit_type_str() under the hood, and the enum visit may + * fail even if the corresponding string visit succeeded; this implies + * that visit_type_str() must have no unwelcome side effects. + */ void visit_type_enum(Visitor *v, const char *name, int *obj, const char *const strings[], Error **errp); + void visit_type_int(Visitor *v, const char *name, int64_t *obj, Error **errp); void visit_type_uint8(Visitor *v, const char *name, uint8_t *obj, Error **errp); diff --git a/include/qapi/visitor-impl.h b/include/qapi/visitor-impl.h index 2bd8f29..51c338a 100644 --- a/include/qapi/visitor-impl.h +++ b/include/qapi/visitor-impl.h @@ -14,6 +14,17 @@ #include "qapi/visitor.h" +/* + * There are three classes of visitors; setting the class determines + * how QAPI enums are visited, as well as what additional restrictions + * can be asserted. + */ +typedef enum VisitorType { + VISITOR_INPUT, + VISITOR_OUTPUT, + VISITOR_DEALLOC, +} VisitorType; + struct Visitor { /* Must be set */ @@ -36,10 +47,6 @@ struct Visitor void (*end_alternate)(Visitor *v); /* Must be set. */ - void (*type_enum)(Visitor *v, const char *name, int *obj, - const char *const strings[], Error **errp); - - /* Must be set. */ void (*type_int64)(Visitor *v, const char *name, int64_t *obj, Error **errp); /* Must be set. */ @@ -58,11 +65,9 @@ struct Visitor /* May be NULL; most useful for input visitors. */ void (*optional)(Visitor *v, const char *name, bool *present); + + /* Must be set */ + VisitorType type; }; -void input_type_enum(Visitor *v, const char *name, int *obj, - const char *const strings[], Error **errp); -void output_type_enum(Visitor *v, const char *name, int *obj, - const char *const strings[], Error **errp); - #endif diff --git a/qapi/qapi-visit-core.c b/qapi/qapi-visit-core.c index fa680c9..3cd7edc 100644 --- a/qapi/qapi-visit-core.c +++ b/qapi/qapi-visit-core.c @@ -72,12 +72,6 @@ bool visit_optional(Visitor *v, const char *name, bool *present) return *present; } -void visit_type_enum(Visitor *v, const char *name, int *obj, - const char *const strings[], Error **errp) -{ - v->type_enum(v, name, obj, strings, errp); -} - void visit_type_int(Visitor *v, const char *name, int64_t *obj, Error **errp) { v->type_int64(v, name, obj, errp); @@ -208,14 +202,13 @@ void visit_type_any(Visitor *v, const char *name, QObject **obj, Error **errp) v->type_any(v, name, obj, errp); } -void output_type_enum(Visitor *v, const char *name, int *obj, - const char *const strings[], Error **errp) +static void output_type_enum(Visitor *v, const char *name, int *obj, + const char *const strings[], Error **errp) { int i = 0; int value = *obj; char *enum_str; - assert(strings); while (strings[i++] != NULL); if (value < 0 || value >= i - 1) { error_setg(errp, QERR_INVALID_PARAMETER, name ? name : "null"); @@ -226,15 +219,13 @@ void output_type_enum(Visitor *v, const char *name, int *obj, visit_type_str(v, name, &enum_str, errp); } -void input_type_enum(Visitor *v, const char *name, int *obj, - const char *const strings[], Error **errp) +static void input_type_enum(Visitor *v, const char *name, int *obj, + const char *const strings[], Error **errp) { Error *local_err = NULL; int64_t value = 0; char *enum_str; - assert(strings); - visit_type_str(v, name, &enum_str, &local_err); if (local_err) { error_propagate(errp, local_err); @@ -257,3 +248,14 @@ void input_type_enum(Visitor *v, const char *name, int *obj, g_free(enum_str); *obj = value; } + +void visit_type_enum(Visitor *v, const char *name, int *obj, + const char *const strings[], Error **errp) +{ + assert(strings); + if (v->type == VISITOR_INPUT) { + input_type_enum(v, name, obj, strings, errp); + } else if (v->type == VISITOR_OUTPUT) { + output_type_enum(v, name, obj, strings, errp); + } +} diff --git a/qapi/opts-visitor.c b/qapi/opts-visitor.c index 602f260..66aeaed 100644 --- a/qapi/opts-visitor.c +++ b/qapi/opts-visitor.c @@ -317,6 +317,11 @@ opts_type_str(Visitor *v, const char *name, char **obj, Error **errp) return; } *obj = g_strdup(opt->str ? opt->str : ""); + /* Note that we consume a string even if this is called as part of + * an enum visit that later fails because the string is not a + * valid enum value; this is harmless because tracking what gets + * consumed only matters to visit_end_struct() as the final error + * check if there were no other failures during the visit. */ processed(ov, name); } @@ -507,6 +512,8 @@ opts_visitor_new(const QemuOpts *opts) ov = g_malloc0(sizeof *ov); + ov->visitor.type = VISITOR_INPUT; + ov->visitor.start_struct = &opts_start_struct; ov->visitor.end_struct = &opts_end_struct; @@ -514,16 +521,6 @@ opts_visitor_new(const QemuOpts *opts) ov->visitor.next_list = &opts_next_list; ov->visitor.end_list = &opts_end_list; - /* input_type_enum() covers both "normal" enums and union discriminators. - * The union discriminator field is always generated as "type"; it should - * match the "type" QemuOpt child of any QemuOpts. - * - * input_type_enum() will remove the looked-up key from the - * "unprocessed_opts" hash even if the lookup fails, because the removal is - * done earlier in opts_type_str(). This should be harmless. - */ - ov->visitor.type_enum = &input_type_enum; - ov->visitor.type_int64 = &opts_type_int64; ov->visitor.type_uint64 = &opts_type_uint64; ov->visitor.type_size = &opts_type_size; diff --git a/qapi/qapi-dealloc-visitor.c b/qapi/qapi-dealloc-visitor.c index 6922179..c19a459 100644 --- a/qapi/qapi-dealloc-visitor.c +++ b/qapi/qapi-dealloc-visitor.c @@ -163,11 +163,6 @@ static void qapi_dealloc_type_anything(Visitor *v, const char *name, } } -static void qapi_dealloc_type_enum(Visitor *v, const char *name, int *obj, - const char * const strings[], Error **errp) -{ -} - Visitor *qapi_dealloc_get_visitor(QapiDeallocVisitor *v) { return &v->visitor; @@ -184,6 +179,7 @@ QapiDeallocVisitor *qapi_dealloc_visitor_new(void) v = g_malloc0(sizeof(*v)); + v->visitor.type = VISITOR_DEALLOC; v->visitor.start_struct = qapi_dealloc_start_struct; v->visitor.end_struct = qapi_dealloc_end_struct; v->visitor.start_alternate = qapi_dealloc_start_alternate; @@ -191,7 +187,6 @@ QapiDeallocVisitor *qapi_dealloc_visitor_new(void) v->visitor.start_list = qapi_dealloc_start_list; v->visitor.next_list = qapi_dealloc_next_list; v->visitor.end_list = qapi_dealloc_end_list; - v->visitor.type_enum = qapi_dealloc_type_enum; v->visitor.type_int64 = qapi_dealloc_type_int64; v->visitor.type_uint64 = qapi_dealloc_type_uint64; v->visitor.type_bool = qapi_dealloc_type_bool; diff --git a/qapi/qmp-input-visitor.c b/qapi/qmp-input-visitor.c index 7cd1b77..02d4233 100644 --- a/qapi/qmp-input-visitor.c +++ b/qapi/qmp-input-visitor.c @@ -339,13 +339,13 @@ QmpInputVisitor *qmp_input_visitor_new(QObject *obj) v = g_malloc0(sizeof(*v)); + v->visitor.type = VISITOR_INPUT; v->visitor.start_struct = qmp_input_start_struct; v->visitor.end_struct = qmp_input_end_struct; v->visitor.start_list = qmp_input_start_list; v->visitor.next_list = qmp_input_next_list; v->visitor.end_list = qmp_input_end_list; v->visitor.start_alternate = qmp_input_start_alternate; - v->visitor.type_enum = input_type_enum; v->visitor.type_int64 = qmp_input_type_int64; v->visitor.type_uint64 = qmp_input_type_uint64; v->visitor.type_bool = qmp_input_type_bool; diff --git a/qapi/qmp-output-visitor.c b/qapi/qmp-output-visitor.c index d44c676..1f2a7ba 100644 --- a/qapi/qmp-output-visitor.c +++ b/qapi/qmp-output-visitor.c @@ -234,12 +234,12 @@ QmpOutputVisitor *qmp_output_visitor_new(void) v = g_malloc0(sizeof(*v)); + v->visitor.type = VISITOR_OUTPUT; v->visitor.start_struct = qmp_output_start_struct; v->visitor.end_struct = qmp_output_end_struct; v->visitor.start_list = qmp_output_start_list; v->visitor.next_list = qmp_output_next_list; v->visitor.end_list = qmp_output_end_list; - v->visitor.type_enum = output_type_enum; v->visitor.type_int64 = qmp_output_type_int64; v->visitor.type_uint64 = qmp_output_type_uint64; v->visitor.type_bool = qmp_output_type_bool; diff --git a/qapi/string-input-visitor.c b/qapi/string-input-visitor.c index ab12953..d604575 100644 --- a/qapi/string-input-visitor.c +++ b/qapi/string-input-visitor.c @@ -348,7 +348,7 @@ StringInputVisitor *string_input_visitor_new(const char *str) v = g_malloc0(sizeof(*v)); - v->visitor.type_enum = input_type_enum; + v->visitor.type = VISITOR_INPUT; v->visitor.type_int64 = parse_type_int64; v->visitor.type_uint64 = parse_type_uint64; v->visitor.type_size = parse_type_size; diff --git a/qapi/string-output-visitor.c b/qapi/string-output-visitor.c index c2e5c5b..0d44d7e 100644 --- a/qapi/string-output-visitor.c +++ b/qapi/string-output-visitor.c @@ -351,7 +351,7 @@ StringOutputVisitor *string_output_visitor_new(bool human) v->string = g_string_new(NULL); v->human = human; - v->visitor.type_enum = output_type_enum; + v->visitor.type = VISITOR_OUTPUT; v->visitor.type_int64 = print_type_int64; v->visitor.type_uint64 = print_type_uint64; v->visitor.type_size = print_type_size;