diff options
Diffstat (limited to 'qapi/opts-visitor.c')
| -rw-r--r-- | qapi/opts-visitor.c | 427 |
1 files changed, 427 insertions, 0 deletions
diff --git a/qapi/opts-visitor.c b/qapi/opts-visitor.c new file mode 100644 index 0000000000..a59d306e46 --- /dev/null +++ b/qapi/opts-visitor.c @@ -0,0 +1,427 @@ +/* + * Options Visitor + * + * Copyright Red Hat, Inc. 2012 + * + * Author: Laszlo Ersek <lersek@redhat.com> + * + * This work is licensed under the terms of the GNU LGPL, version 2.1 or later. + * See the COPYING.LIB file in the top-level directory. + * + */ + +#include "opts-visitor.h" +#include "qemu-queue.h" +#include "qemu-option-internal.h" +#include "qapi-visit-impl.h" + + +struct OptsVisitor +{ + Visitor visitor; + + /* Ownership remains with opts_visitor_new()'s caller. */ + const QemuOpts *opts_root; + + unsigned depth; + + /* Non-null iff depth is positive. Each key is a QemuOpt name. Each value + * is a non-empty GQueue, enumerating all QemuOpt occurrences with that + * name. */ + GHashTable *unprocessed_opts; + + /* 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. */ + 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 + * not survive or escape the OptsVisitor object. + */ + QemuOpt *fake_id_opt; +}; + + +static void +destroy_list(gpointer list) +{ + g_queue_free(list); +} + + +static void +opts_visitor_insert(GHashTable *unprocessed_opts, const QemuOpt *opt) +{ + GQueue *list; + + list = g_hash_table_lookup(unprocessed_opts, opt->name); + if (list == NULL) { + list = g_queue_new(); + + /* GHashTable will never try to free the keys -- we supply NULL as + * "key_destroy_func" in opts_start_struct(). Thus cast away key + * const-ness in order to suppress gcc's warning. + */ + g_hash_table_insert(unprocessed_opts, (gpointer)opt->name, list); + } + + /* Similarly, destroy_list() doesn't call g_queue_free_full(). */ + g_queue_push_tail(list, (gpointer)opt); +} + + +static void +opts_start_struct(Visitor *v, void **obj, const char *kind, + const char *name, size_t size, Error **errp) +{ + OptsVisitor *ov = DO_UPCAST(OptsVisitor, visitor, v); + const QemuOpt *opt; + + *obj = g_malloc0(size > 0 ? size : 1); + if (ov->depth++ > 0) { + return; + } + + ov->unprocessed_opts = g_hash_table_new_full(&g_str_hash, &g_str_equal, + NULL, &destroy_list); + QTAILQ_FOREACH(opt, &ov->opts_root->head, next) { + /* ensured by qemu-option.c::opts_do_parse() */ + assert(strcmp(opt->name, "id") != 0); + + opts_visitor_insert(ov->unprocessed_opts, opt); + } + + if (ov->opts_root->id != NULL) { + ov->fake_id_opt = g_malloc0(sizeof *ov->fake_id_opt); + + ov->fake_id_opt->name = "id"; + ov->fake_id_opt->str = ov->opts_root->id; + opts_visitor_insert(ov->unprocessed_opts, ov->fake_id_opt); + } +} + + +static gboolean +ghr_true(gpointer ign_key, gpointer ign_value, gpointer ign_user_data) +{ + return TRUE; +} + + +static void +opts_end_struct(Visitor *v, Error **errp) +{ + OptsVisitor *ov = DO_UPCAST(OptsVisitor, visitor, v); + GQueue *any; + + if (--ov->depth > 0) { + return; + } + + /* we should have processed all (distinct) QemuOpt instances */ + any = g_hash_table_find(ov->unprocessed_opts, &ghr_true, NULL); + if (any) { + const QemuOpt *first; + + first = g_queue_peek_head(any); + error_set(errp, QERR_INVALID_PARAMETER, first->name); + } + g_hash_table_destroy(ov->unprocessed_opts); + ov->unprocessed_opts = NULL; + g_free(ov->fake_id_opt); + ov->fake_id_opt = NULL; +} + + +static GQueue * +lookup_distinct(const OptsVisitor *ov, const char *name, Error **errp) +{ + GQueue *list; + + list = g_hash_table_lookup(ov->unprocessed_opts, name); + if (!list) { + error_set(errp, QERR_MISSING_PARAMETER, name); + } + return list; +} + + +static void +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); + ov->repeated_opts = lookup_distinct(ov, name, errp); + ov->repeated_opts_first = (ov->repeated_opts != NULL); +} + + +static GenericList * +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; + link = list; + } else { + const QemuOpt *opt; + + opt = g_queue_pop_head(ov->repeated_opts); + if (g_queue_is_empty(ov->repeated_opts)) { + g_hash_table_remove(ov->unprocessed_opts, opt->name); + return NULL; + } + link = &(*list)->next; + } + + *link = g_malloc0(sizeof **link); + return *link; +} + + +static void +opts_end_list(Visitor *v, Error **errp) +{ + OptsVisitor *ov = DO_UPCAST(OptsVisitor, visitor, v); + + ov->repeated_opts = NULL; +} + + +static const QemuOpt * +lookup_scalar(const OptsVisitor *ov, const char *name, Error **errp) +{ + if (ov->repeated_opts == NULL) { + GQueue *list; + + /* the last occurrence of any QemuOpt takes effect when queried by name + */ + list = lookup_distinct(ov, name, errp); + return list ? g_queue_peek_tail(list) : NULL; + } + return g_queue_peek_head(ov->repeated_opts); +} + + +static void +processed(OptsVisitor *ov, const char *name) +{ + if (ov->repeated_opts == NULL) { + g_hash_table_remove(ov->unprocessed_opts, name); + } +} + + +static void +opts_type_str(Visitor *v, char **obj, const char *name, Error **errp) +{ + OptsVisitor *ov = DO_UPCAST(OptsVisitor, visitor, v); + const QemuOpt *opt; + + opt = lookup_scalar(ov, name, errp); + if (!opt) { + return; + } + *obj = g_strdup(opt->str ? opt->str : ""); + processed(ov, name); +} + + +/* mimics qemu-option.c::parse_option_bool() */ +static void +opts_type_bool(Visitor *v, bool *obj, const char *name, Error **errp) +{ + OptsVisitor *ov = DO_UPCAST(OptsVisitor, visitor, v); + const QemuOpt *opt; + + opt = lookup_scalar(ov, name, errp); + if (!opt) { + return; + } + + if (opt->str) { + if (strcmp(opt->str, "on") == 0 || + strcmp(opt->str, "yes") == 0 || + strcmp(opt->str, "y") == 0) { + *obj = true; + } else if (strcmp(opt->str, "off") == 0 || + strcmp(opt->str, "no") == 0 || + strcmp(opt->str, "n") == 0) { + *obj = false; + } else { + error_set(errp, QERR_INVALID_PARAMETER_VALUE, opt->name, + "on|yes|y|off|no|n"); + return; + } + } else { + *obj = true; + } + + processed(ov, name); +} + + +static void +opts_type_int(Visitor *v, int64_t *obj, const char *name, Error **errp) +{ + OptsVisitor *ov = DO_UPCAST(OptsVisitor, visitor, v); + const QemuOpt *opt; + const char *str; + long long val; + char *endptr; + + opt = lookup_scalar(ov, name, errp); + if (!opt) { + return; + } + str = opt->str ? opt->str : ""; + + errno = 0; + val = strtoll(str, &endptr, 0); + if (*str != '\0' && *endptr == '\0' && errno == 0 && INT64_MIN <= val && + val <= INT64_MAX) { + *obj = val; + processed(ov, name); + return; + } + error_set(errp, QERR_INVALID_PARAMETER_VALUE, opt->name, "an int64 value"); +} + + +static void +opts_type_uint64(Visitor *v, uint64_t *obj, const char *name, Error **errp) +{ + OptsVisitor *ov = DO_UPCAST(OptsVisitor, visitor, v); + const QemuOpt *opt; + const char *str; + + opt = lookup_scalar(ov, name, errp); + if (!opt) { + return; + } + + str = opt->str; + if (str != NULL) { + while (isspace((unsigned char)*str)) { + ++str; + } + + if (*str != '-' && *str != '\0') { + unsigned long long val; + char *endptr; + + /* non-empty, non-negative subject sequence */ + errno = 0; + val = strtoull(str, &endptr, 0); + if (*endptr == '\0' && errno == 0 && val <= UINT64_MAX) { + *obj = val; + processed(ov, name); + return; + } + } + } + error_set(errp, QERR_INVALID_PARAMETER_VALUE, opt->name, + "an uint64 value"); +} + + +static void +opts_type_size(Visitor *v, uint64_t *obj, const char *name, Error **errp) +{ + OptsVisitor *ov = DO_UPCAST(OptsVisitor, visitor, v); + const QemuOpt *opt; + int64_t val; + char *endptr; + + opt = lookup_scalar(ov, name, errp); + if (!opt) { + return; + } + + val = strtosz_suffix(opt->str ? opt->str : "", &endptr, + STRTOSZ_DEFSUFFIX_B); + if (val != -1 && *endptr == '\0') { + *obj = val; + processed(ov, name); + return; + } + error_set(errp, QERR_INVALID_PARAMETER_VALUE, opt->name, + "a size value representible as a non-negative int64"); +} + + +static void +opts_start_optional(Visitor *v, bool *present, const char *name, + Error **errp) +{ + OptsVisitor *ov = DO_UPCAST(OptsVisitor, visitor, v); + + /* we only support a single mandatory scalar field in a list node */ + assert(ov->repeated_opts == NULL); + *present = (lookup_distinct(ov, name, NULL) != NULL); +} + + +OptsVisitor * +opts_visitor_new(const QemuOpts *opts) +{ + OptsVisitor *ov; + + ov = g_malloc0(sizeof *ov); + + ov->visitor.start_struct = &opts_start_struct; + ov->visitor.end_struct = &opts_end_struct; + + ov->visitor.start_list = &opts_start_list; + 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_int = &opts_type_int; + ov->visitor.type_uint64 = &opts_type_uint64; + ov->visitor.type_size = &opts_type_size; + ov->visitor.type_bool = &opts_type_bool; + ov->visitor.type_str = &opts_type_str; + + /* type_number() is not filled in, but this is not the first visitor to + * skip some mandatory methods... */ + + ov->visitor.start_optional = &opts_start_optional; + + ov->opts_root = opts; + + return ov; +} + + +void +opts_visitor_cleanup(OptsVisitor *ov) +{ + if (ov->unprocessed_opts != NULL) { + g_hash_table_destroy(ov->unprocessed_opts); + } + g_free(ov->fake_id_opt); + memset(ov, '\0', sizeof *ov); +} + + +Visitor * +opts_get_visitor(OptsVisitor *ov) +{ + return &ov->visitor; +} |