From d95704341280fc521dc2b16bbbc5858f6647e2c3 Mon Sep 17 00:00:00 2001 From: Laszlo Ersek Date: Tue, 20 Aug 2013 00:35:33 +0200 Subject: OptsVisitor: introduce basic list modes We're going to need more state while processing a list of repeated options. This change eliminates "repeated_opts_first" and adds a new state variable: list_mode repeated_opts repeated_opts_first -------------- ------------- ------------------- LM_NONE NULL false LM_STARTED non-NULL true LM_IN_PROGRESS non-NULL false Additionally, it is documented that lookup_scalar() and processed(), both called by opts_type_XXX(), are invalid in LM_STARTED -- generated qapi code calls opts_next_list() to allocate the very first link before trying to parse a scalar into it. List mode restrictions are expressed in positive / inclusive form. Signed-off-by: Laszlo Ersek Tested-by: Wanlong Gao Signed-off-by: Luiz Capitulino --- qapi/opts-visitor.c | 45 +++++++++++++++++++++++++++++++++++---------- 1 file changed, 35 insertions(+), 10 deletions(-) (limited to 'qapi') diff --git a/qapi/opts-visitor.c b/qapi/opts-visitor.c index 174bd8bdb0..29fd1abd95 100644 --- a/qapi/opts-visitor.c +++ b/qapi/opts-visitor.c @@ -1,7 +1,7 @@ /* * Options Visitor * - * Copyright Red Hat, Inc. 2012 + * Copyright Red Hat, Inc. 2012, 2013 * * Author: Laszlo Ersek * @@ -18,6 +18,15 @@ #include "qapi/visitor-impl.h" +enum ListMode +{ + LM_NONE, /* not traversing a list of repeated options */ + LM_STARTED, /* opts_start_list() succeeded */ + LM_IN_PROGRESS /* opts_next_list() has been called */ +}; + +typedef enum ListMode ListMode; + struct OptsVisitor { Visitor visitor; @@ -35,8 +44,8 @@ struct OptsVisitor /* The list currently being traversed with opts_start_list() / * opts_next_list(). The list must have a struct element type in the * schema, with a single mandatory scalar member. */ + ListMode list_mode; GQueue *repeated_opts; - bool repeated_opts_first; /* If "opts_root->id" is set, reinstantiate it as a fake QemuOpt for * uniformity. Only its "name" and "str" fields are set. "fake_id_opt" does @@ -156,9 +165,11 @@ opts_start_list(Visitor *v, const char *name, Error **errp) OptsVisitor *ov = DO_UPCAST(OptsVisitor, visitor, v); /* we can't traverse a list in a list */ - assert(ov->repeated_opts == NULL); + assert(ov->list_mode == LM_NONE); ov->repeated_opts = lookup_distinct(ov, name, errp); - ov->repeated_opts_first = (ov->repeated_opts != NULL); + if (ov->repeated_opts != NULL) { + ov->list_mode = LM_STARTED; + } } @@ -168,10 +179,13 @@ opts_next_list(Visitor *v, GenericList **list, Error **errp) OptsVisitor *ov = DO_UPCAST(OptsVisitor, visitor, v); GenericList **link; - if (ov->repeated_opts_first) { - ov->repeated_opts_first = false; + switch (ov->list_mode) { + case LM_STARTED: + ov->list_mode = LM_IN_PROGRESS; link = list; - } else { + break; + + case LM_IN_PROGRESS: { const QemuOpt *opt; opt = g_queue_pop_head(ov->repeated_opts); @@ -180,6 +194,11 @@ opts_next_list(Visitor *v, GenericList **list, Error **errp) return NULL; } link = &(*list)->next; + break; + } + + default: + abort(); } *link = g_malloc0(sizeof **link); @@ -192,14 +211,16 @@ opts_end_list(Visitor *v, Error **errp) { OptsVisitor *ov = DO_UPCAST(OptsVisitor, visitor, v); + assert(ov->list_mode == LM_STARTED || ov->list_mode == LM_IN_PROGRESS); ov->repeated_opts = NULL; + ov->list_mode = LM_NONE; } static const QemuOpt * lookup_scalar(const OptsVisitor *ov, const char *name, Error **errp) { - if (ov->repeated_opts == NULL) { + if (ov->list_mode == LM_NONE) { GQueue *list; /* the last occurrence of any QemuOpt takes effect when queried by name @@ -207,6 +228,7 @@ lookup_scalar(const OptsVisitor *ov, const char *name, Error **errp) list = lookup_distinct(ov, name, errp); return list ? g_queue_peek_tail(list) : NULL; } + assert(ov->list_mode == LM_IN_PROGRESS); return g_queue_peek_head(ov->repeated_opts); } @@ -214,9 +236,12 @@ lookup_scalar(const OptsVisitor *ov, const char *name, Error **errp) static void processed(OptsVisitor *ov, const char *name) { - if (ov->repeated_opts == NULL) { + if (ov->list_mode == LM_NONE) { g_hash_table_remove(ov->unprocessed_opts, name); + return; } + assert(ov->list_mode == LM_IN_PROGRESS); + /* do nothing */ } @@ -365,7 +390,7 @@ opts_start_optional(Visitor *v, bool *present, const char *name, OptsVisitor *ov = DO_UPCAST(OptsVisitor, visitor, v); /* we only support a single mandatory scalar field in a list node */ - assert(ov->repeated_opts == NULL); + assert(ov->list_mode == LM_NONE); *present = (lookup_distinct(ov, name, NULL) != NULL); } -- cgit v1.2.1