Introduce Virtio-loopback epsilon release:

Epsilon release introduces a new compatibility layer which make virtio-loopback
design to work with QEMU and rust-vmm vhost-user backend without require any
changes.

Signed-off-by: Timos Ampelikiotis <t.ampelikiotis@virtualopensystems.com>
Change-Id: I52e57563e08a7d0bdc002f8e928ee61ba0c53dd9

1 files changed, 1226 insertions, 0 deletions

diff --git a/util/qemu-option.c b/util/qemu-option.c
new file mode 100644
index 000000000..eedd08929
--- /dev/null
+++ b/util/qemu-option.c
@@ -0,0 +1,1226 @@
+/*
+ * Commandline option parsing functions
+ *
+ * Copyright (c) 2003-2008 Fabrice Bellard
+ * Copyright (c) 2009 Kevin Wolf <kwolf@redhat.com>
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
+ * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+
+#include "qemu/osdep.h"
+
+#include "qapi/error.h"
+#include "qemu/error-report.h"
+#include "qapi/qmp/qbool.h"
+#include "qapi/qmp/qdict.h"
+#include "qapi/qmp/qnum.h"
+#include "qapi/qmp/qstring.h"
+#include "qapi/qmp/qerror.h"
+#include "qemu/option_int.h"
+#include "qemu/cutils.h"
+#include "qemu/id.h"
+#include "qemu/help_option.h"
+
+/*
+ * Extracts the name of an option from the parameter string (@p points at the
+ * first byte of the option name)
+ *
+ * The option name is @len characters long and is copied into @option. The
+ * caller is responsible for free'ing @option when no longer required.
+ *
+ * The return value is the position of the delimiter/zero byte after the option
+ * name in @p.
+ */
+static const char *get_opt_name(const char *p, char **option, size_t len)
+{
+    *option = g_strndup(p, len);
+    return p + len;
+}
+
+/*
+ * Extracts the value of an option from the parameter string p (p points at the
+ * first byte of the option value)
+ *
+ * This function is comparable to get_opt_name with the difference that the
+ * delimiter is fixed to be comma which starts a new option. To specify an
+ * option value that contains commas, double each comma.
+ */
+const char *get_opt_value(const char *p, char **value)
+{
+    size_t capacity = 0, length;
+    const char *offset;
+
+    *value = NULL;
+    while (1) {
+        offset = qemu_strchrnul(p, ',');
+        length = offset - p;
+        if (*offset != '\0' && *(offset + 1) == ',') {
+            length++;
+        }
+        *value = g_renew(char, *value, capacity + length + 1);
+        strncpy(*value + capacity, p, length);
+        (*value)[capacity + length] = '\0';
+        capacity += length;
+        if (*offset == '\0' ||
+            *(offset + 1) != ',') {
+            break;
+        }
+
+        p += (offset - p) + 2;
+    }
+
+    return offset;
+}
+
+static bool parse_option_number(const char *name, const char *value,
+                                uint64_t *ret, Error **errp)
+{
+    uint64_t number;
+    int err;
+
+    err = qemu_strtou64(value, NULL, 0, &number);
+    if (err == -ERANGE) {
+        error_setg(errp, "Value '%s' is too large for parameter '%s'",
+                   value, name);
+        return false;
+    }
+    if (err) {
+        error_setg(errp, QERR_INVALID_PARAMETER_VALUE, name, "a number");
+        return false;
+    }
+    *ret = number;
+    return true;
+}
+
+static const QemuOptDesc *find_desc_by_name(const QemuOptDesc *desc,
+                                            const char *name)
+{
+    int i;
+
+    for (i = 0; desc[i].name != NULL; i++) {
+        if (strcmp(desc[i].name, name) == 0) {
+            return &desc[i];
+        }
+    }
+
+    return NULL;
+}
+
+static const char *find_default_by_name(QemuOpts *opts, const char *name)
+{
+    const QemuOptDesc *desc = find_desc_by_name(opts->list->desc, name);
+
+    return desc ? desc->def_value_str : NULL;
+}
+
+bool parse_option_size(const char *name, const char *value,
+                       uint64_t *ret, Error **errp)
+{
+    uint64_t size;
+    int err;
+
+    err = qemu_strtosz(value, NULL, &size);
+    if (err == -ERANGE) {
+        error_setg(errp, "Value '%s' is out of range for parameter '%s'",
+                   value, name);
+        return false;
+    }
+    if (err) {
+        error_setg(errp, QERR_INVALID_PARAMETER_VALUE, name,
+                   "a non-negative number below 2^64");
+        error_append_hint(errp, "Optional suffix k, M, G, T, P or E means"
+                          " kilo-, mega-, giga-, tera-, peta-\n"
+                          "and exabytes, respectively.\n");
+        return false;
+    }
+    *ret = size;
+    return true;
+}
+
+static const char *opt_type_to_string(enum QemuOptType type)
+{
+    switch (type) {
+    case QEMU_OPT_STRING:
+        return "str";
+    case QEMU_OPT_BOOL:
+        return "bool (on/off)";
+    case QEMU_OPT_NUMBER:
+        return "num";
+    case QEMU_OPT_SIZE:
+        return "size";
+    }
+
+    g_assert_not_reached();
+}
+
+/**
+ * Print the list of options available in the given list.  If
+ * @print_caption is true, a caption (including the list name, if it
+ * exists) is printed.  The options itself will be indented, so
+ * @print_caption should only be set to false if the caller prints its
+ * own custom caption (so that the indentation makes sense).
+ */
+void qemu_opts_print_help(QemuOptsList *list, bool print_caption)
+{
+    QemuOptDesc *desc;
+    int i;
+    GPtrArray *array = g_ptr_array_new();
+
+    assert(list);
+    desc = list->desc;
+    while (desc && desc->name) {
+        GString *str = g_string_new(NULL);
+        g_string_append_printf(str, "  %s=<%s>", desc->name,
+                               opt_type_to_string(desc->type));
+        if (desc->help) {
+            if (str->len < 24) {
+                g_string_append_printf(str, "%*s", 24 - (int)str->len, "");
+            }
+            g_string_append_printf(str, " - %s", desc->help);
+        }
+        g_ptr_array_add(array, g_string_free(str, false));
+        desc++;
+    }
+
+    g_ptr_array_sort(array, (GCompareFunc)qemu_pstrcmp0);
+    if (print_caption && array->len > 0) {
+        if (list->name) {
+            printf("%s options:\n", list->name);
+        } else {
+            printf("Options:\n");
+        }
+    } else if (array->len == 0) {
+        if (list->name) {
+            printf("There are no options for %s.\n", list->name);
+        } else {
+            printf("No options available.\n");
+        }
+    }
+    for (i = 0; i < array->len; i++) {
+        printf("%s\n", (char *)array->pdata[i]);
+    }
+    g_ptr_array_set_free_func(array, g_free);
+    g_ptr_array_free(array, true);
+
+}
+/* ------------------------------------------------------------------ */
+
+QemuOpt *qemu_opt_find(QemuOpts *opts, const char *name)
+{
+    QemuOpt *opt;
+
+    QTAILQ_FOREACH_REVERSE(opt, &opts->head, next) {
+        if (strcmp(opt->name, name) != 0)
+            continue;
+        return opt;
+    }
+    return NULL;
+}
+
+static void qemu_opt_del(QemuOpt *opt)
+{
+    QTAILQ_REMOVE(&opt->opts->head, opt, next);
+    g_free(opt->name);
+    g_free(opt->str);
+    g_free(opt);
+}
+
+/* qemu_opt_set allows many settings for the same option.
+ * This function deletes all settings for an option.
+ */
+static void qemu_opt_del_all(QemuOpts *opts, const char *name)
+{
+    QemuOpt *opt, *next_opt;
+
+    QTAILQ_FOREACH_SAFE(opt, &opts->head, next, next_opt) {
+        if (!strcmp(opt->name, name)) {
+            qemu_opt_del(opt);
+        }
+    }
+}
+
+const char *qemu_opt_get(QemuOpts *opts, const char *name)
+{
+    QemuOpt *opt;
+
+    if (opts == NULL) {
+        return NULL;
+    }
+
+    opt = qemu_opt_find(opts, name);
+    if (!opt) {
+        return find_default_by_name(opts, name);
+    }
+
+    return opt->str;
+}
+
+void qemu_opt_iter_init(QemuOptsIter *iter, QemuOpts *opts, const char *name)
+{
+    iter->opts = opts;
+    iter->opt = QTAILQ_FIRST(&opts->head);
+    iter->name = name;
+}
+
+const char *qemu_opt_iter_next(QemuOptsIter *iter)
+{
+    QemuOpt *ret = iter->opt;
+    if (iter->name) {
+        while (ret && !g_str_equal(iter->name, ret->name)) {
+            ret = QTAILQ_NEXT(ret, next);
+        }
+    }
+    iter->opt = ret ? QTAILQ_NEXT(ret, next) : NULL;
+    return ret ? ret->str : NULL;
+}
+
+/* Get a known option (or its default) and remove it from the list
+ * all in one action. Return a malloced string of the option value.
+ * Result must be freed by caller with g_free().
+ */
+char *qemu_opt_get_del(QemuOpts *opts, const char *name)
+{
+    QemuOpt *opt;
+    char *str;
+
+    if (opts == NULL) {
+        return NULL;
+    }
+
+    opt = qemu_opt_find(opts, name);
+    if (!opt) {
+        return g_strdup(find_default_by_name(opts, name));
+    }
+    str = opt->str;
+    opt->str = NULL;
+    qemu_opt_del_all(opts, name);
+    return str;
+}
+
+bool qemu_opt_has_help_opt(QemuOpts *opts)
+{
+    QemuOpt *opt;
+
+    QTAILQ_FOREACH_REVERSE(opt, &opts->head, next) {
+        if (is_help_option(opt->name)) {
+            return true;
+        }
+    }
+    return false;
+}
+
+static bool qemu_opt_get_bool_helper(QemuOpts *opts, const char *name,
+                                     bool defval, bool del)
+{
+    QemuOpt *opt;
+    const char *def_val;
+    bool ret = defval;
+
+    if (opts == NULL) {
+        return ret;
+    }
+
+    opt = qemu_opt_find(opts, name);
+    if (opt == NULL) {
+        def_val = find_default_by_name(opts, name);
+        if (def_val) {
+            qapi_bool_parse(name, def_val, &ret, &error_abort);
+        }
+        return ret;
+    }
+    assert(opt->desc && opt->desc->type == QEMU_OPT_BOOL);
+    ret = opt->value.boolean;
+    if (del) {
+        qemu_opt_del_all(opts, name);
+    }
+    return ret;
+}
+
+bool qemu_opt_get_bool(QemuOpts *opts, const char *name, bool defval)
+{
+    return qemu_opt_get_bool_helper(opts, name, defval, false);
+}
+
+bool qemu_opt_get_bool_del(QemuOpts *opts, const char *name, bool defval)
+{
+    return qemu_opt_get_bool_helper(opts, name, defval, true);
+}
+
+static uint64_t qemu_opt_get_number_helper(QemuOpts *opts, const char *name,
+                                           uint64_t defval, bool del)
+{
+    QemuOpt *opt;
+    const char *def_val;
+    uint64_t ret = defval;
+
+    if (opts == NULL) {
+        return ret;
+    }
+
+    opt = qemu_opt_find(opts, name);
+    if (opt == NULL) {
+        def_val = find_default_by_name(opts, name);
+        if (def_val) {
+            parse_option_number(name, def_val, &ret, &error_abort);
+        }
+        return ret;
+    }
+    assert(opt->desc && opt->desc->type == QEMU_OPT_NUMBER);
+    ret = opt->value.uint;
+    if (del) {
+        qemu_opt_del_all(opts, name);
+    }
+    return ret;
+}
+
+uint64_t qemu_opt_get_number(QemuOpts *opts, const char *name, uint64_t defval)
+{
+    return qemu_opt_get_number_helper(opts, name, defval, false);
+}
+
+uint64_t qemu_opt_get_number_del(QemuOpts *opts, const char *name,
+                                 uint64_t defval)
+{
+    return qemu_opt_get_number_helper(opts, name, defval, true);
+}
+
+static uint64_t qemu_opt_get_size_helper(QemuOpts *opts, const char *name,
+                                         uint64_t defval, bool del)
+{
+    QemuOpt *opt;
+    const char *def_val;
+    uint64_t ret = defval;
+
+    if (opts == NULL) {
+        return ret;
+    }
+
+    opt = qemu_opt_find(opts, name);
+    if (opt == NULL) {
+        def_val = find_default_by_name(opts, name);
+        if (def_val) {
+            parse_option_size(name, def_val, &ret, &error_abort);
+        }
+        return ret;
+    }
+    assert(opt->desc && opt->desc->type == QEMU_OPT_SIZE);
+    ret = opt->value.uint;
+    if (del) {
+        qemu_opt_del_all(opts, name);
+    }
+    return ret;
+}
+
+uint64_t qemu_opt_get_size(QemuOpts *opts, const char *name, uint64_t defval)
+{
+    return qemu_opt_get_size_helper(opts, name, defval, false);
+}
+
+uint64_t qemu_opt_get_size_del(QemuOpts *opts, const char *name,
+                               uint64_t defval)
+{
+    return qemu_opt_get_size_helper(opts, name, defval, true);
+}
+
+static bool qemu_opt_parse(QemuOpt *opt, Error **errp)
+{
+    if (opt->desc == NULL)
+        return true;
+
+    switch (opt->desc->type) {
+    case QEMU_OPT_STRING:
+        /* nothing */
+        return true;
+    case QEMU_OPT_BOOL:
+        return qapi_bool_parse(opt->name, opt->str, &opt->value.boolean, errp);
+    case QEMU_OPT_NUMBER:
+        return parse_option_number(opt->name, opt->str, &opt->value.uint,
+                                   errp);
+    case QEMU_OPT_SIZE:
+        return parse_option_size(opt->name, opt->str, &opt->value.uint,
+                                 errp);
+    default:
+        abort();
+    }
+}
+
+static bool opts_accepts_any(const QemuOptsList *list)
+{
+    return list->desc[0].name == NULL;
+}
+
+int qemu_opt_unset(QemuOpts *opts, const char *name)
+{
+    QemuOpt *opt = qemu_opt_find(opts, name);
+
+    assert(opts_accepts_any(opts->list));
+
+    if (opt == NULL) {
+        return -1;
+    } else {
+        qemu_opt_del(opt);
+        return 0;
+    }
+}
+
+static QemuOpt *opt_create(QemuOpts *opts, const char *name, char *value)
+{
+    QemuOpt *opt = g_malloc0(sizeof(*opt));
+
+    opt->name = g_strdup(name);
+    opt->str = value;
+    opt->opts = opts;
+    QTAILQ_INSERT_TAIL(&opts->head, opt, next);
+
+    return opt;
+}
+
+static bool opt_validate(QemuOpt *opt, Error **errp)
+{
+    const QemuOptDesc *desc;
+    const QemuOptsList *list = opt->opts->list;
+
+    desc = find_desc_by_name(list->desc, opt->name);
+    if (!desc && !opts_accepts_any(list)) {
+        error_setg(errp, QERR_INVALID_PARAMETER, opt->name);
+        return false;
+    }
+
+    opt->desc = desc;
+    if (!qemu_opt_parse(opt, errp)) {
+        return false;
+    }
+
+    return true;
+}
+
+bool qemu_opt_set(QemuOpts *opts, const char *name, const char *value,
+                  Error **errp)
+{
+    QemuOpt *opt = opt_create(opts, name, g_strdup(value));
+
+    if (!opt_validate(opt, errp)) {
+        qemu_opt_del(opt);
+        return false;
+    }
+    return true;
+}
+
+bool qemu_opt_set_bool(QemuOpts *opts, const char *name, bool val,
+                       Error **errp)
+{
+    QemuOpt *opt;
+    const QemuOptDesc *desc;
+    const QemuOptsList *list = opts->list;
+
+    desc = find_desc_by_name(list->desc, name);
+    if (!desc && !opts_accepts_any(list)) {
+        error_setg(errp, QERR_INVALID_PARAMETER, name);
+        return false;
+    }
+
+    opt = g_malloc0(sizeof(*opt));
+    opt->name = g_strdup(name);
+    opt->opts = opts;
+    opt->desc = desc;
+    opt->value.boolean = !!val;
+    opt->str = g_strdup(val ? "on" : "off");
+    QTAILQ_INSERT_TAIL(&opts->head, opt, next);
+    return true;
+}
+
+bool qemu_opt_set_number(QemuOpts *opts, const char *name, int64_t val,
+                         Error **errp)
+{
+    QemuOpt *opt;
+    const QemuOptDesc *desc;
+    const QemuOptsList *list = opts->list;
+
+    desc = find_desc_by_name(list->desc, name);
+    if (!desc && !opts_accepts_any(list)) {
+        error_setg(errp, QERR_INVALID_PARAMETER, name);
+        return false;
+    }
+
+    opt = g_malloc0(sizeof(*opt));
+    opt->name = g_strdup(name);
+    opt->opts = opts;
+    opt->desc = desc;
+    opt->value.uint = val;
+    opt->str = g_strdup_printf("%" PRId64, val);
+    QTAILQ_INSERT_TAIL(&opts->head, opt, next);
+    return true;
+}
+
+/**
+ * For each member of @opts, call @func(@opaque, name, value, @errp).
+ * @func() may store an Error through @errp, but must return non-zero then.
+ * When @func() returns non-zero, break the loop and return that value.
+ * Return zero when the loop completes.
+ */
+int qemu_opt_foreach(QemuOpts *opts, qemu_opt_loopfunc func, void *opaque,
+                     Error **errp)
+{
+    QemuOpt *opt;
+    int rc;
+
+    QTAILQ_FOREACH(opt, &opts->head, next) {
+        rc = func(opaque, opt->name, opt->str, errp);
+        if (rc) {
+            return rc;
+        }
+        assert(!errp || !*errp);
+    }
+    return 0;
+}
+
+QemuOpts *qemu_opts_find(QemuOptsList *list, const char *id)
+{
+    QemuOpts *opts;
+
+    QTAILQ_FOREACH(opts, &list->head, next) {
+        if (!opts->id && !id) {
+            return opts;
+        }
+        if (opts->id && id && !strcmp(opts->id, id)) {
+            return opts;
+        }
+    }
+    return NULL;
+}
+
+QemuOpts *qemu_opts_create(QemuOptsList *list, const char *id,
+                           int fail_if_exists, Error **errp)
+{
+    QemuOpts *opts = NULL;
+
+    if (list->merge_lists) {
+        if (id) {
+            error_setg(errp, QERR_INVALID_PARAMETER, "id");
+            return NULL;
+        }
+        opts = qemu_opts_find(list, NULL);
+        if (opts) {
+            return opts;
+        }
+    } else if (id) {
+        assert(fail_if_exists);
+        if (!id_wellformed(id)) {
+            error_setg(errp, QERR_INVALID_PARAMETER_VALUE, "id",
+                       "an identifier");
+            error_append_hint(errp, "Identifiers consist of letters, digits, "
+                              "'-', '.', '_', starting with a letter.\n");
+            return NULL;
+        }
+        opts = qemu_opts_find(list, id);
+        if (opts != NULL) {
+            error_setg(errp, "Duplicate ID '%s' for %s", id, list->name);
+            return NULL;
+        }
+    }
+    opts = g_malloc0(sizeof(*opts));
+    opts->id = g_strdup(id);
+    opts->list = list;
+    loc_save(&opts->loc);
+    QTAILQ_INIT(&opts->head);
+    QTAILQ_INSERT_TAIL(&list->head, opts, next);
+    return opts;
+}
+
+void qemu_opts_reset(QemuOptsList *list)
+{
+    QemuOpts *opts, *next_opts;
+
+    QTAILQ_FOREACH_SAFE(opts, &list->head, next, next_opts) {
+        qemu_opts_del(opts);
+    }
+}
+
+void qemu_opts_loc_restore(QemuOpts *opts)
+{
+    loc_restore(&opts->loc);
+}
+
+const char *qemu_opts_id(QemuOpts *opts)
+{
+    return opts->id;
+}
+
+/* The id string will be g_free()d by qemu_opts_del */
+void qemu_opts_set_id(QemuOpts *opts, char *id)
+{
+    opts->id = id;
+}
+
+void qemu_opts_del(QemuOpts *opts)
+{
+    QemuOpt *opt;
+
+    if (opts == NULL) {
+        return;
+    }
+
+    for (;;) {
+        opt = QTAILQ_FIRST(&opts->head);
+        if (opt == NULL)
+            break;
+        qemu_opt_del(opt);
+    }
+    QTAILQ_REMOVE(&opts->list->head, opts, next);
+    g_free(opts->id);
+    g_free(opts);
+}
+
+/* print value, escaping any commas in value */
+static void escaped_print(const char *value)
+{
+    const char *ptr;
+
+    for (ptr = value; *ptr; ++ptr) {
+        if (*ptr == ',') {
+            putchar(',');
+        }
+        putchar(*ptr);
+    }
+}
+
+void qemu_opts_print(QemuOpts *opts, const char *separator)
+{
+    QemuOpt *opt;
+    QemuOptDesc *desc = opts->list->desc;
+    const char *sep = "";
+
+    if (opts->id) {
+        printf("id=%s", opts->id); /* passed id_wellformed -> no commas */
+        sep = separator;
+    }
+
+    if (desc[0].name == NULL) {
+        QTAILQ_FOREACH(opt, &opts->head, next) {
+            printf("%s%s=", sep, opt->name);
+            escaped_print(opt->str);
+            sep = separator;
+        }
+        return;
+    }
+    for (; desc && desc->name; desc++) {
+        const char *value;
+        opt = qemu_opt_find(opts, desc->name);
+
+        value = opt ? opt->str : desc->def_value_str;
+        if (!value) {
+            continue;
+        }
+        if (desc->type == QEMU_OPT_STRING) {
+            printf("%s%s=", sep, desc->name);
+            escaped_print(value);
+        } else if ((desc->type == QEMU_OPT_SIZE ||
+                    desc->type == QEMU_OPT_NUMBER) && opt) {
+            printf("%s%s=%" PRId64, sep, desc->name, opt->value.uint);
+        } else {
+            printf("%s%s=%s", sep, desc->name, value);
+        }
+        sep = separator;
+    }
+}
+
+static const char *get_opt_name_value(const char *params,
+                                      const char *firstname,
+                                      bool warn_on_flag,
+                                      bool *help_wanted,
+                                      char **name, char **value)
+{
+    const char *p;
+    const char *prefix = "";
+    size_t len;
+    bool is_help = false;
+
+    len = strcspn(params, "=,");
+    if (params[len] != '=') {
+        /* found "foo,more" */
+        if (firstname) {
+            /* implicitly named first option */
+            *name = g_strdup(firstname);
+            p = get_opt_value(params, value);
+        } else {
+            /* option without value, must be a flag */
+            p = get_opt_name(params, name, len);
+            if (strncmp(*name, "no", 2) == 0) {
+                memmove(*name, *name + 2, strlen(*name + 2) + 1);
+                *value = g_strdup("off");
+                prefix = "no";
+            } else {
+                *value = g_strdup("on");
+                is_help = is_help_option(*name);
+            }
+            if (!is_help && warn_on_flag) {
+                warn_report("short-form boolean option '%s%s' deprecated", prefix, *name);
+                if (g_str_equal(*name, "delay")) {
+                    error_printf("Please use nodelay=%s instead\n", prefix[0] ? "on" : "off");
+                } else {
+                    error_printf("Please use %s=%s instead\n", *name, *value);
+                }
+            }
+        }
+    } else {
+        /* found "foo=bar,more" */
+        p = get_opt_name(params, name, len);
+        assert(*p == '=');
+        p++;
+        p = get_opt_value(p, value);
+    }
+
+    assert(!*p || *p == ',');
+    if (help_wanted && is_help) {
+        *help_wanted = true;
+    }
+    if (*p == ',') {
+        p++;
+    }
+    return p;
+}
+
+static bool opts_do_parse(QemuOpts *opts, const char *params,
+                          const char *firstname,
+                          bool warn_on_flag, bool *help_wanted, Error **errp)
+{
+    char *option, *value;
+    const char *p;
+    QemuOpt *opt;
+
+    for (p = params; *p;) {
+        p = get_opt_name_value(p, firstname, warn_on_flag, help_wanted, &option, &value);
+        if (help_wanted && *help_wanted) {
+            g_free(option);
+            g_free(value);
+            return false;
+        }
+        firstname = NULL;
+
+        if (!strcmp(option, "id")) {
+            g_free(option);
+            g_free(value);
+            continue;
+        }
+
+        opt = opt_create(opts, option, value);
+        g_free(option);
+        if (!opt_validate(opt, errp)) {
+            qemu_opt_del(opt);
+            return false;
+        }
+    }
+
+    return true;
+}
+
+static char *opts_parse_id(const char *params)
+{
+    const char *p;
+    char *name, *value;
+
+    for (p = params; *p;) {
+        p = get_opt_name_value(p, NULL, false, NULL, &name, &value);
+        if (!strcmp(name, "id")) {
+            g_free(name);
+            return value;
+        }
+        g_free(name);
+        g_free(value);
+    }
+
+    return NULL;
+}
+
+bool has_help_option(const char *params)
+{
+    const char *p;
+    char *name, *value;
+    bool ret = false;
+
+    for (p = params; *p;) {
+        p = get_opt_name_value(p, NULL, false, &ret, &name, &value);
+        g_free(name);
+        g_free(value);
+        if (ret) {
+            return true;
+        }
+    }
+
+    return false;
+}
+
+/**
+ * Store options parsed from @params into @opts.
+ * If @firstname is non-null, the first key=value in @params may omit
+ * key=, and is treated as if key was @firstname.
+ * On error, store an error object through @errp if non-null.
+ */
+bool qemu_opts_do_parse(QemuOpts *opts, const char *params,
+                       const char *firstname, Error **errp)
+{
+    return opts_do_parse(opts, params, firstname, false, NULL, errp);
+}
+
+static QemuOpts *opts_parse(QemuOptsList *list, const char *params,
+                            bool permit_abbrev,
+                            bool warn_on_flag, bool *help_wanted, Error **errp)
+{
+    const char *firstname;
+    char *id = opts_parse_id(params);
+    QemuOpts *opts;
+
+    assert(!permit_abbrev || list->implied_opt_name);
+    firstname = permit_abbrev ? list->implied_opt_name : NULL;
+
+    opts = qemu_opts_create(list, id, !list->merge_lists, errp);
+    g_free(id);
+    if (opts == NULL) {
+        return NULL;
+    }
+
+    if (!opts_do_parse(opts, params, firstname,
+                       warn_on_flag, help_wanted, errp)) {
+        qemu_opts_del(opts);
+        return NULL;
+    }
+
+    return opts;
+}
+
+/**
+ * Create a QemuOpts in @list and with options parsed from @params.
+ * If @permit_abbrev, the first key=value in @params may omit key=,
+ * and is treated as if key was @list->implied_opt_name.
+ * On error, store an error object through @errp if non-null.
+ * Return the new QemuOpts on success, null pointer on error.
+ */
+QemuOpts *qemu_opts_parse(QemuOptsList *list, const char *params,
+                          bool permit_abbrev, Error **errp)
+{
+    return opts_parse(list, params, permit_abbrev, false, NULL, errp);
+}
+
+/**
+ * Create a QemuOpts in @list and with options parsed from @params.
+ * If @permit_abbrev, the first key=value in @params may omit key=,
+ * and is treated as if key was @list->implied_opt_name.
+ * Report errors with error_report_err().  This is inappropriate in
+ * QMP context.  Do not use this function there!
+ * Return the new QemuOpts on success, null pointer on error.
+ */
+QemuOpts *qemu_opts_parse_noisily(QemuOptsList *list, const char *params,
+                                  bool permit_abbrev)
+{
+    Error *err = NULL;
+    QemuOpts *opts;
+    bool help_wanted = false;
+
+    opts = opts_parse(list, params, permit_abbrev, true,
+                      opts_accepts_any(list) ? NULL : &help_wanted,
+                      &err);
+    if (!opts) {
+        assert(!!err + !!help_wanted == 1);
+        if (help_wanted) {
+            qemu_opts_print_help(list, true);
+        } else {
+            error_report_err(err);
+        }
+    }
+    return opts;
+}
+
+static bool qemu_opts_from_qdict_entry(QemuOpts *opts,
+                                       const QDictEntry *entry,
+                                       Error **errp)
+{
+    const char *key = qdict_entry_key(entry);
+    QObject *obj = qdict_entry_value(entry);
+    char buf[32];
+    g_autofree char *tmp = NULL;
+    const char *value;
+
+    if (!strcmp(key, "id")) {
+        return true;
+    }
+
+    switch (qobject_type(obj)) {
+    case QTYPE_QSTRING:
+        value = qstring_get_str(qobject_to(QString, obj));
+        break;
+    case QTYPE_QNUM:
+        tmp = qnum_to_string(qobject_to(QNum, obj));
+        value = tmp;
+        break;
+    case QTYPE_QBOOL:
+        pstrcpy(buf, sizeof(buf),
+                qbool_get_bool(qobject_to(QBool, obj)) ? "on" : "off");
+        value = buf;
+        break;
+    default:
+        return true;
+    }
+
+    return qemu_opt_set(opts, key, value, errp);
+}
+
+/*
+ * Create QemuOpts from a QDict.
+ * Use value of key "id" as ID if it exists and is a QString.  Only
+ * QStrings, QNums and QBools are copied.  Entries with other types
+ * are silently ignored.
+ */
+QemuOpts *qemu_opts_from_qdict(QemuOptsList *list, const QDict *qdict,
+                               Error **errp)
+{
+    QemuOpts *opts;
+    const QDictEntry *entry;
+
+    opts = qemu_opts_create(list, qdict_get_try_str(qdict, "id"), 1, errp);
+    if (!opts) {
+        return NULL;
+    }
+
+    for (entry = qdict_first(qdict);
+         entry;
+         entry = qdict_next(qdict, entry)) {
+        if (!qemu_opts_from_qdict_entry(opts, entry, errp)) {
+            qemu_opts_del(opts);
+            return NULL;
+        }
+    }
+
+    return opts;
+}
+
+/*
+ * Adds all QDict entries to the QemuOpts that can be added and removes them
+ * from the QDict. When this function returns, the QDict contains only those
+ * entries that couldn't be added to the QemuOpts.
+ */
+bool qemu_opts_absorb_qdict(QemuOpts *opts, QDict *qdict, Error **errp)
+{
+    const QDictEntry *entry, *next;
+
+    entry = qdict_first(qdict);
+
+    while (entry != NULL) {
+        next = qdict_next(qdict, entry);
+
+        if (opts_accepts_any(opts->list) ||
+            find_desc_by_name(opts->list->desc, entry->key)) {
+            if (!qemu_opts_from_qdict_entry(opts, entry, errp)) {
+                return false;
+            }
+            qdict_del(qdict, entry->key);
+        }
+
+        entry = next;
+    }
+
+    return true;
+}
+
+/*
+ * Convert from QemuOpts to QDict. The QDict values are of type QString.
+ *
+ * If @list is given, only add those options to the QDict that are contained in
+ * the list. If @del is true, any options added to the QDict are removed from
+ * the QemuOpts, otherwise they remain there.
+ *
+ * If two options in @opts have the same name, they are processed in order
+ * so that the last one wins (consistent with the reverse iteration in
+ * qemu_opt_find()), but all of them are deleted if @del is true.
+ *
+ * TODO We'll want to use types appropriate for opt->desc->type, but
+ * this is enough for now.
+ */
+QDict *qemu_opts_to_qdict_filtered(QemuOpts *opts, QDict *qdict,
+                                   QemuOptsList *list, bool del)
+{
+    QemuOpt *opt, *next;
+
+    if (!qdict) {
+        qdict = qdict_new();
+    }
+    if (opts->id) {
+        qdict_put_str(qdict, "id", opts->id);
+    }
+    QTAILQ_FOREACH_SAFE(opt, &opts->head, next, next) {
+        if (list) {
+            QemuOptDesc *desc;
+            bool found = false;
+            for (desc = list->desc; desc->name; desc++) {
+                if (!strcmp(desc->name, opt->name)) {
+                    found = true;
+                    break;
+                }
+            }
+            if (!found) {
+                continue;
+            }
+        }
+        qdict_put_str(qdict, opt->name, opt->str);
+        if (del) {
+            qemu_opt_del(opt);
+        }
+    }
+    return qdict;
+}
+
+/* Copy all options in a QemuOpts to the given QDict. See
+ * qemu_opts_to_qdict_filtered() for details. */
+QDict *qemu_opts_to_qdict(QemuOpts *opts, QDict *qdict)
+{
+    return qemu_opts_to_qdict_filtered(opts, qdict, NULL, false);
+}
+
+/* Validate parsed opts against descriptions where no
+ * descriptions were provided in the QemuOptsList.
+ */
+bool qemu_opts_validate(QemuOpts *opts, const QemuOptDesc *desc, Error **errp)
+{
+    QemuOpt *opt;
+
+    assert(opts_accepts_any(opts->list));
+
+    QTAILQ_FOREACH(opt, &opts->head, next) {
+        opt->desc = find_desc_by_name(desc, opt->name);
+        if (!opt->desc) {
+            error_setg(errp, QERR_INVALID_PARAMETER, opt->name);
+            return false;
+        }
+
+        if (!qemu_opt_parse(opt, errp)) {
+            return false;
+        }
+    }
+
+    return true;
+}
+
+/**
+ * For each member of @list, call @func(@opaque, member, @errp).
+ * Call it with the current location temporarily set to the member's.
+ * @func() may store an Error through @errp, but must return non-zero then.
+ * When @func() returns non-zero, break the loop and return that value.
+ * Return zero when the loop completes.
+ */
+int qemu_opts_foreach(QemuOptsList *list, qemu_opts_loopfunc func,
+                      void *opaque, Error **errp)
+{
+    Location loc;
+    QemuOpts *opts, *next;
+    int rc = 0;
+
+    loc_push_none(&loc);
+    QTAILQ_FOREACH_SAFE(opts, &list->head, next, next) {
+        loc_restore(&opts->loc);
+        rc = func(opaque, opts, errp);
+        if (rc) {
+            break;
+        }
+        assert(!errp || !*errp);
+    }
+    loc_pop(&loc);
+    return rc;
+}
+
+static size_t count_opts_list(QemuOptsList *list)
+{
+    QemuOptDesc *desc = NULL;
+    size_t num_opts = 0;
+
+    if (!list) {
+        return 0;
+    }
+
+    desc = list->desc;
+    while (desc && desc->name) {
+        num_opts++;
+        desc++;
+    }
+
+    return num_opts;
+}
+
+void qemu_opts_free(QemuOptsList *list)
+{
+    g_free(list);
+}
+
+/* Realloc dst option list and append options from an option list (list)
+ * to it. dst could be NULL or a malloced list.
+ * The lifetime of dst must be shorter than the input list because the
+ * QemuOptDesc->name, ->help, and ->def_value_str strings are shared.
+ */
+QemuOptsList *qemu_opts_append(QemuOptsList *dst,
+                               QemuOptsList *list)
+{
+    size_t num_opts, num_dst_opts;
+    QemuOptDesc *desc;
+    bool need_init = false;
+    bool need_head_update;
+
+    if (!list) {
+        return dst;
+    }
+
+    /* If dst is NULL, after realloc, some area of dst should be initialized
+     * before adding options to it.
+     */
+    if (!dst) {
+        need_init = true;
+        need_head_update = true;
+    } else {
+        /* Moreover, even if dst is not NULL, the realloc may move it to a
+         * different address in which case we may get a stale tail pointer
+         * in dst->head. */
+        need_head_update = QTAILQ_EMPTY(&dst->head);
+    }
+
+    num_opts = count_opts_list(dst);
+    num_dst_opts = num_opts;
+    num_opts += count_opts_list(list);
+    dst = g_realloc(dst, sizeof(QemuOptsList) +
+                    (num_opts + 1) * sizeof(QemuOptDesc));
+    if (need_init) {
+        dst->name = NULL;
+        dst->implied_opt_name = NULL;
+        dst->merge_lists = false;
+    }
+    if (need_head_update) {
+        QTAILQ_INIT(&dst->head);
+    }
+    dst->desc[num_dst_opts].name = NULL;
+
+    /* append list->desc to dst->desc */
+    if (list) {
+        desc = list->desc;
+        while (desc && desc->name) {
+            if (find_desc_by_name(dst->desc, desc->name) == NULL) {
+                dst->desc[num_dst_opts++] = *desc;
+                dst->desc[num_dst_opts].name = NULL;
+            }
+            desc++;
+        }
+    }
+
+    return dst;
+}