diff mbox

[v24,02/31] QemuOpts: add def_value_str to QemuOptDesc

Message ID 1396518889-21681-3-git-send-email-cyliu@suse.com
State New
Headers show

Commit Message

Chunyan Liu April 3, 2014, 9:54 a.m. UTC 
Add def_value_str (default value) to QemuOptDesc, to replace function of the
default value in QEMUOptionParameter.

Improve qemu_opts_get_* functions: if find opt, return opt->str; otherwise,
if desc->def_value_str is set, return desc->def_value_str; otherwise, return
input defval.

Improve qemu_opts_print: if option is set, print opt->str; otherwise, if
desc->def_value_str is set, also print it.

Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Dong Xu Wang <wdongxu@linux.vnet.ibm.com>
Signed-off-by: Chunyan Liu <cyliu@suse.com>
---
 include/qemu/option.h |  3 ++-
 util/qemu-option.c    | 56 ++++++++++++++++++++++++++++++++++++++++++---------
 2 files changed, 49 insertions(+), 10 deletions(-)

Comments

Leandro Dorileo April 8, 2014, 1:31 a.m. UTC | #1 
On Thu, Apr 03, 2014 at 05:54:20PM +0800, Chunyan Liu wrote:
> Add def_value_str (default value) to QemuOptDesc, to replace function of the
> default value in QEMUOptionParameter.
> 
> Improve qemu_opts_get_* functions: if find opt, return opt->str; otherwise,
> if desc->def_value_str is set, return desc->def_value_str; otherwise, return
> input defval.
> 
> Improve qemu_opts_print: if option is set, print opt->str; otherwise, if
> desc->def_value_str is set, also print it.
> 
> Reviewed-by: Eric Blake <eblake@redhat.com>
> Signed-off-by: Dong Xu Wang <wdongxu@linux.vnet.ibm.com>
> Signed-off-by: Chunyan Liu <cyliu@suse.com>
> ---
>  include/qemu/option.h |  3 ++-
>  util/qemu-option.c    | 56 ++++++++++++++++++++++++++++++++++++++++++---------
>  2 files changed, 49 insertions(+), 10 deletions(-)
> 
> diff --git a/include/qemu/option.h b/include/qemu/option.h
> index 8c0ac34..c3b0a91 100644
> --- a/include/qemu/option.h
> +++ b/include/qemu/option.h
> @@ -99,6 +99,7 @@ typedef struct QemuOptDesc {
>      const char *name;
>      enum QemuOptType type;
>      const char *help;
> +    const char *def_value_str;
>  } QemuOptDesc;


I still think you don't need to define the default value as a string to later
parse it, see what I mean https://lists.gnu.org/archive/html/qemu-devel/2014-03/msg04273.html

But I think we can live with it. See bellow, if you fix the issue you can add my Reviewed-by.


>  
>  struct QemuOptsList {
> @@ -156,7 +157,7 @@ QDict *qemu_opts_to_qdict(QemuOpts *opts, QDict *qdict);
>  void qemu_opts_absorb_qdict(QemuOpts *opts, QDict *qdict, Error **errp);
>  
>  typedef int (*qemu_opts_loopfunc)(QemuOpts *opts, void *opaque);
> -int qemu_opts_print(QemuOpts *opts, void *dummy);
> +void qemu_opts_print(QemuOpts *opts);
>  int qemu_opts_foreach(QemuOptsList *list, qemu_opts_loopfunc func, void *opaque,
>                        int abort_on_failure);
>  
> diff --git a/util/qemu-option.c b/util/qemu-option.c
> index e6d10bc..d5e80da 100644
> --- a/util/qemu-option.c
> +++ b/util/qemu-option.c
> @@ -570,6 +570,13 @@ static QemuOpt *qemu_opt_find(QemuOpts *opts, const char *name)
>  const char *qemu_opt_get(QemuOpts *opts, const char *name)
>  {
>      QemuOpt *opt = qemu_opt_find(opts, name);
> +
> +    if (!opt) {
> +        const QemuOptDesc *desc = find_desc_by_name(opts->list->desc, name);
> +        if (desc && desc->def_value_str) {
> +            return desc->def_value_str;
> +        }
> +    }
>      return opt ? opt->str : NULL;
>  }
>  
> @@ -589,8 +596,13 @@ bool qemu_opt_get_bool(QemuOpts *opts, const char *name, bool defval)
>  {
>      QemuOpt *opt = qemu_opt_find(opts, name);
>  
> -    if (opt == NULL)
> +    if (opt == NULL) {
> +        const QemuOptDesc *desc = find_desc_by_name(opts->list->desc, name);
> +        if (desc && desc->def_value_str) {
> +            parse_option_bool(name, desc->def_value_str, &defval, &error_abort);
> +        }
>          return defval;
> +    }
>      assert(opt->desc && opt->desc->type == QEMU_OPT_BOOL);
>      return opt->value.boolean;
>  }
> @@ -599,8 +611,14 @@ uint64_t qemu_opt_get_number(QemuOpts *opts, const char *name, uint64_t defval)
>  {
>      QemuOpt *opt = qemu_opt_find(opts, name);
>  
> -    if (opt == NULL)
> +    if (opt == NULL) {
> +        const QemuOptDesc *desc = find_desc_by_name(opts->list->desc, name);
> +        if (desc && desc->def_value_str) {
> +            parse_option_number(name, desc->def_value_str, &defval,
> +                                &error_abort);
> +        }
>          return defval;
> +    }
>      assert(opt->desc && opt->desc->type == QEMU_OPT_NUMBER);
>      return opt->value.uint;
>  }
> @@ -609,8 +627,13 @@ uint64_t qemu_opt_get_size(QemuOpts *opts, const char *name, uint64_t defval)
>  {
>      QemuOpt *opt = qemu_opt_find(opts, name);
>  
> -    if (opt == NULL)
> +    if (opt == NULL) {
> +        const QemuOptDesc *desc = find_desc_by_name(opts->list->desc, name);
> +        if (desc && desc->def_value_str) {
> +            parse_option_size(name, desc->def_value_str, &defval, &error_abort);
> +        }
>          return defval;
> +    }
>      assert(opt->desc && opt->desc->type == QEMU_OPT_SIZE);
>      return opt->value.uint;
>  }
> @@ -895,17 +918,32 @@ void qemu_opts_del(QemuOpts *opts)
>      g_free(opts);
>  }
>  
> -int qemu_opts_print(QemuOpts *opts, void *dummy)
> +void qemu_opts_print(QemuOpts *opts)
>  {
>      QemuOpt *opt;
> +    QemuOptDesc *desc = opts->list->desc;
>  
> -    fprintf(stderr, "%s: %s:", opts->list->name,
> -            opts->id ? opts->id : "<noid>");
> -    QTAILQ_FOREACH(opt, &opts->head, next) {
> -        fprintf(stderr, " %s=\"%s\"", opt->name, opt->str);
> +    if (desc[0].name == NULL) {
> +        QTAILQ_FOREACH(opt, &opts->head, next) {
> +            fprintf(stderr, "%s=\"%s\" ", opt->name, opt->str);
> +        }
> +        return;
> +    }
> +    for (; desc && desc->name; desc++) {
> +        const char *value;
> +        QemuOpt *opt = qemu_opt_find(opts, desc->name);
> +
> +        value = opt ? opt->str : desc->def_value_str;
> +        if (!value) {
> +            continue;
> +        }
> +        if (desc->type == QEMU_OPT_STRING) {
> +            fprintf(stderr, "%s='%s' ", desc->name, value);
> +        } else {
> +            fprintf(stderr, "%s=%s ", desc->name, value);
> +        }
>      }
>      fprintf(stderr, "\n");



I see you removed this fprintf() in the commit afe65f5c92694d551aaebc128233b623e8665d5e
Please do this change in this commit and avoid breaking the block tests in
further commits.
Chunyan Liu April 10, 2014, 3:36 a.m. UTC | #2 
2014-04-08 9:31 GMT+08:00 Leandro Dorileo <l@dorileo.org>:

> On Thu, Apr 03, 2014 at 05:54:20PM +0800, Chunyan Liu wrote:
> > Add def_value_str (default value) to QemuOptDesc, to replace function of
> the
> > default value in QEMUOptionParameter.
> >
> > Improve qemu_opts_get_* functions: if find opt, return opt->str;
> otherwise,
> > if desc->def_value_str is set, return desc->def_value_str; otherwise,
> return
> > input defval.
> >
> > Improve qemu_opts_print: if option is set, print opt->str; otherwise, if
> > desc->def_value_str is set, also print it.
> >
> > Reviewed-by: Eric Blake <eblake@redhat.com>
> > Signed-off-by: Dong Xu Wang <wdongxu@linux.vnet.ibm.com>
> > Signed-off-by: Chunyan Liu <cyliu@suse.com>
> > ---
> >  include/qemu/option.h |  3 ++-
> >  util/qemu-option.c    | 56
> ++++++++++++++++++++++++++++++++++++++++++---------
> >  2 files changed, 49 insertions(+), 10 deletions(-)
> >
> > diff --git a/include/qemu/option.h b/include/qemu/option.h
> > index 8c0ac34..c3b0a91 100644
> > --- a/include/qemu/option.h
> > +++ b/include/qemu/option.h
> > @@ -99,6 +99,7 @@ typedef struct QemuOptDesc {
> >      const char *name;
> >      enum QemuOptType type;
> >      const char *help;
> > +    const char *def_value_str;
> >  } QemuOptDesc;
>
>
> I still think you don't need to define the default value as a string to
> later
> parse it, see what I mean
> https://lists.gnu.org/archive/html/qemu-devel/2014-03/msg04273.html
>
> But I think we can live with it. See bellow, if you fix the issue you can
> add my Reviewed-by.
>
>
> >
> >  struct QemuOptsList {
> > @@ -156,7 +157,7 @@ QDict *qemu_opts_to_qdict(QemuOpts *opts, QDict
> *qdict);
> >  void qemu_opts_absorb_qdict(QemuOpts *opts, QDict *qdict, Error **errp);
> >
> >  typedef int (*qemu_opts_loopfunc)(QemuOpts *opts, void *opaque);
> > -int qemu_opts_print(QemuOpts *opts, void *dummy);
> > +void qemu_opts_print(QemuOpts *opts);
> >  int qemu_opts_foreach(QemuOptsList *list, qemu_opts_loopfunc func, void
> *opaque,
> >                        int abort_on_failure);
> >
> > diff --git a/util/qemu-option.c b/util/qemu-option.c
> > index e6d10bc..d5e80da 100644
> > --- a/util/qemu-option.c
> > +++ b/util/qemu-option.c
> > @@ -570,6 +570,13 @@ static QemuOpt *qemu_opt_find(QemuOpts *opts, const
> char *name)
> >  const char *qemu_opt_get(QemuOpts *opts, const char *name)
> >  {
> >      QemuOpt *opt = qemu_opt_find(opts, name);
> > +
> > +    if (!opt) {
> > +        const QemuOptDesc *desc = find_desc_by_name(opts->list->desc,
> name);
> > +        if (desc && desc->def_value_str) {
> > +            return desc->def_value_str;
> > +        }
> > +    }
> >      return opt ? opt->str : NULL;
> >  }
> >
> > @@ -589,8 +596,13 @@ bool qemu_opt_get_bool(QemuOpts *opts, const char
> *name, bool defval)
> >  {
> >      QemuOpt *opt = qemu_opt_find(opts, name);
> >
> > -    if (opt == NULL)
> > +    if (opt == NULL) {
> > +        const QemuOptDesc *desc = find_desc_by_name(opts->list->desc,
> name);
> > +        if (desc && desc->def_value_str) {
> > +            parse_option_bool(name, desc->def_value_str, &defval,
> &error_abort);
> > +        }
> >          return defval;
> > +    }
> >      assert(opt->desc && opt->desc->type == QEMU_OPT_BOOL);
> >      return opt->value.boolean;
> >  }
> > @@ -599,8 +611,14 @@ uint64_t qemu_opt_get_number(QemuOpts *opts, const
> char *name, uint64_t defval)
> >  {
> >      QemuOpt *opt = qemu_opt_find(opts, name);
> >
> > -    if (opt == NULL)
> > +    if (opt == NULL) {
> > +        const QemuOptDesc *desc = find_desc_by_name(opts->list->desc,
> name);
> > +        if (desc && desc->def_value_str) {
> > +            parse_option_number(name, desc->def_value_str, &defval,
> > +                                &error_abort);
> > +        }
> >          return defval;
> > +    }
> >      assert(opt->desc && opt->desc->type == QEMU_OPT_NUMBER);
> >      return opt->value.uint;
> >  }
> > @@ -609,8 +627,13 @@ uint64_t qemu_opt_get_size(QemuOpts *opts, const
> char *name, uint64_t defval)
> >  {
> >      QemuOpt *opt = qemu_opt_find(opts, name);
> >
> > -    if (opt == NULL)
> > +    if (opt == NULL) {
> > +        const QemuOptDesc *desc = find_desc_by_name(opts->list->desc,
> name);
> > +        if (desc && desc->def_value_str) {
> > +            parse_option_size(name, desc->def_value_str, &defval,
> &error_abort);
> > +        }
> >          return defval;
> > +    }
> >      assert(opt->desc && opt->desc->type == QEMU_OPT_SIZE);
> >      return opt->value.uint;
> >  }
> > @@ -895,17 +918,32 @@ void qemu_opts_del(QemuOpts *opts)
> >      g_free(opts);
> >  }
> >
> > -int qemu_opts_print(QemuOpts *opts, void *dummy)
> > +void qemu_opts_print(QemuOpts *opts)
> >  {
> >      QemuOpt *opt;
> > +    QemuOptDesc *desc = opts->list->desc;
> >
> > -    fprintf(stderr, "%s: %s:", opts->list->name,
> > -            opts->id ? opts->id : "<noid>");
> > -    QTAILQ_FOREACH(opt, &opts->head, next) {
> > -        fprintf(stderr, " %s=\"%s\"", opt->name, opt->str);
> > +    if (desc[0].name == NULL) {
> > +        QTAILQ_FOREACH(opt, &opts->head, next) {
> > +            fprintf(stderr, "%s=\"%s\" ", opt->name, opt->str);
> > +        }
> > +        return;
> > +    }
> > +    for (; desc && desc->name; desc++) {
> > +        const char *value;
> > +        QemuOpt *opt = qemu_opt_find(opts, desc->name);
> > +
> > +        value = opt ? opt->str : desc->def_value_str;
> > +        if (!value) {
> > +            continue;
> > +        }
> > +        if (desc->type == QEMU_OPT_STRING) {
> > +            fprintf(stderr, "%s='%s' ", desc->name, value);
> > +        } else {
> > +            fprintf(stderr, "%s=%s ", desc->name, value);
> > +        }
> >      }
> >      fprintf(stderr, "\n");
>
>
>
> I see you removed this fprintf() in the commit
> afe65f5c92694d551aaebc128233b623e8665d5e
> Please do this change in this commit and avoid breaking the block tests in
> further commits.
>
>
This function won't be used until
0012-change-block-layer-to-support-both-QemuOpts-and-QEMU.patch.
It won't break block tests. The commit
afe65f5c92694d551aaebc128233b623e8665d5e
could be squashed with this commit directly. I split it into two steps just
to make
each patch easy to review, since in previous version, switching fprintf to
printf
in this patch was complained. But sure I can merge these two patches  if you
still think it's better.

Chunyan


> --
> Leandro Dorileo
>
> > -    return 0;
> >  }
> >
> >  static int opts_do_parse(QemuOpts *opts, const char *params,
> > --
> > 1.7.12.4
> >
>
>
Leandro Dorileo April 16, 2014, 8:14 p.m. UTC | #3 
On Thu, Apr 10, 2014 at 11:36:05AM +0800, Chunyan Liu wrote:
> 2014-04-08 9:31 GMT+08:00 Leandro Dorileo <l@dorileo.org>:
> 
> > On Thu, Apr 03, 2014 at 05:54:20PM +0800, Chunyan Liu wrote:
> > > Add def_value_str (default value) to QemuOptDesc, to replace function of
> > the
> > > default value in QEMUOptionParameter.
> > >
> > > Improve qemu_opts_get_* functions: if find opt, return opt->str;
> > otherwise,
> > > if desc->def_value_str is set, return desc->def_value_str; otherwise,
> > return
> > > input defval.
> > >
> > > Improve qemu_opts_print: if option is set, print opt->str; otherwise, if
> > > desc->def_value_str is set, also print it.
> > >
> > > Reviewed-by: Eric Blake <eblake@redhat.com>
> > > Signed-off-by: Dong Xu Wang <wdongxu@linux.vnet.ibm.com>
> > > Signed-off-by: Chunyan Liu <cyliu@suse.com>
> > > ---
> > >  include/qemu/option.h |  3 ++-
> > >  util/qemu-option.c    | 56
> > ++++++++++++++++++++++++++++++++++++++++++---------
> > >  2 files changed, 49 insertions(+), 10 deletions(-)
> > >
> > > diff --git a/include/qemu/option.h b/include/qemu/option.h
> > > index 8c0ac34..c3b0a91 100644
> > > --- a/include/qemu/option.h
> > > +++ b/include/qemu/option.h
> > > @@ -99,6 +99,7 @@ typedef struct QemuOptDesc {
> > >      const char *name;
> > >      enum QemuOptType type;
> > >      const char *help;
> > > +    const char *def_value_str;
> > >  } QemuOptDesc;
> >
> >
> > I still think you don't need to define the default value as a string to
> > later
> > parse it, see what I mean
> > https://lists.gnu.org/archive/html/qemu-devel/2014-03/msg04273.html
> >
> > But I think we can live with it. See bellow, if you fix the issue you can
> > add my Reviewed-by.
> >
> >
> > >
> > >  struct QemuOptsList {
> > > @@ -156,7 +157,7 @@ QDict *qemu_opts_to_qdict(QemuOpts *opts, QDict
> > *qdict);
> > >  void qemu_opts_absorb_qdict(QemuOpts *opts, QDict *qdict, Error **errp);
> > >
> > >  typedef int (*qemu_opts_loopfunc)(QemuOpts *opts, void *opaque);
> > > -int qemu_opts_print(QemuOpts *opts, void *dummy);
> > > +void qemu_opts_print(QemuOpts *opts);
> > >  int qemu_opts_foreach(QemuOptsList *list, qemu_opts_loopfunc func, void
> > *opaque,
> > >                        int abort_on_failure);
> > >
> > > diff --git a/util/qemu-option.c b/util/qemu-option.c
> > > index e6d10bc..d5e80da 100644
> > > --- a/util/qemu-option.c
> > > +++ b/util/qemu-option.c
> > > @@ -570,6 +570,13 @@ static QemuOpt *qemu_opt_find(QemuOpts *opts, const
> > char *name)
> > >  const char *qemu_opt_get(QemuOpts *opts, const char *name)
> > >  {
> > >      QemuOpt *opt = qemu_opt_find(opts, name);
> > > +
> > > +    if (!opt) {
> > > +        const QemuOptDesc *desc = find_desc_by_name(opts->list->desc,
> > name);
> > > +        if (desc && desc->def_value_str) {
> > > +            return desc->def_value_str;
> > > +        }
> > > +    }
> > >      return opt ? opt->str : NULL;
> > >  }
> > >
> > > @@ -589,8 +596,13 @@ bool qemu_opt_get_bool(QemuOpts *opts, const char
> > *name, bool defval)
> > >  {
> > >      QemuOpt *opt = qemu_opt_find(opts, name);
> > >
> > > -    if (opt == NULL)
> > > +    if (opt == NULL) {
> > > +        const QemuOptDesc *desc = find_desc_by_name(opts->list->desc,
> > name);
> > > +        if (desc && desc->def_value_str) {
> > > +            parse_option_bool(name, desc->def_value_str, &defval,
> > &error_abort);
> > > +        }
> > >          return defval;
> > > +    }
> > >      assert(opt->desc && opt->desc->type == QEMU_OPT_BOOL);
> > >      return opt->value.boolean;
> > >  }
> > > @@ -599,8 +611,14 @@ uint64_t qemu_opt_get_number(QemuOpts *opts, const
> > char *name, uint64_t defval)
> > >  {
> > >      QemuOpt *opt = qemu_opt_find(opts, name);
> > >
> > > -    if (opt == NULL)
> > > +    if (opt == NULL) {
> > > +        const QemuOptDesc *desc = find_desc_by_name(opts->list->desc,
> > name);
> > > +        if (desc && desc->def_value_str) {
> > > +            parse_option_number(name, desc->def_value_str, &defval,
> > > +                                &error_abort);
> > > +        }
> > >          return defval;
> > > +    }
> > >      assert(opt->desc && opt->desc->type == QEMU_OPT_NUMBER);
> > >      return opt->value.uint;
> > >  }
> > > @@ -609,8 +627,13 @@ uint64_t qemu_opt_get_size(QemuOpts *opts, const
> > char *name, uint64_t defval)
> > >  {
> > >      QemuOpt *opt = qemu_opt_find(opts, name);
> > >
> > > -    if (opt == NULL)
> > > +    if (opt == NULL) {
> > > +        const QemuOptDesc *desc = find_desc_by_name(opts->list->desc,
> > name);
> > > +        if (desc && desc->def_value_str) {
> > > +            parse_option_size(name, desc->def_value_str, &defval,
> > &error_abort);
> > > +        }
> > >          return defval;
> > > +    }
> > >      assert(opt->desc && opt->desc->type == QEMU_OPT_SIZE);
> > >      return opt->value.uint;
> > >  }
> > > @@ -895,17 +918,32 @@ void qemu_opts_del(QemuOpts *opts)
> > >      g_free(opts);
> > >  }
> > >
> > > -int qemu_opts_print(QemuOpts *opts, void *dummy)
> > > +void qemu_opts_print(QemuOpts *opts)
> > >  {
> > >      QemuOpt *opt;
> > > +    QemuOptDesc *desc = opts->list->desc;
> > >
> > > -    fprintf(stderr, "%s: %s:", opts->list->name,
> > > -            opts->id ? opts->id : "<noid>");
> > > -    QTAILQ_FOREACH(opt, &opts->head, next) {
> > > -        fprintf(stderr, " %s=\"%s\"", opt->name, opt->str);
> > > +    if (desc[0].name == NULL) {
> > > +        QTAILQ_FOREACH(opt, &opts->head, next) {
> > > +            fprintf(stderr, "%s=\"%s\" ", opt->name, opt->str);
> > > +        }
> > > +        return;
> > > +    }
> > > +    for (; desc && desc->name; desc++) {
> > > +        const char *value;
> > > +        QemuOpt *opt = qemu_opt_find(opts, desc->name);
> > > +
> > > +        value = opt ? opt->str : desc->def_value_str;
> > > +        if (!value) {
> > > +            continue;
> > > +        }
> > > +        if (desc->type == QEMU_OPT_STRING) {
> > > +            fprintf(stderr, "%s='%s' ", desc->name, value);
> > > +        } else {
> > > +            fprintf(stderr, "%s=%s ", desc->name, value);
> > > +        }
> > >      }
> > >      fprintf(stderr, "\n");
> >
> >
> >
> > I see you removed this fprintf() in the commit
> > afe65f5c92694d551aaebc128233b623e8665d5e
> > Please do this change in this commit and avoid breaking the block tests in
> > further commits.
> >
> >
> This function won't be used until
> 0012-change-block-layer-to-support-both-QemuOpts-and-QEMU.patch.
> It won't break block tests. The commit
> afe65f5c92694d551aaebc128233b623e8665d5e
> could be squashed with this commit directly. I split it into two steps just
> to make
> each patch easy to review, since in previous version, switching fprintf to
> printf
> in this patch was complained. But sure I can merge these two patches  if you
> still think it's better.
> 

Ok, sounds good.


> Chunyan
> 
> 
> > --
> > Leandro Dorileo
> >
> > > -    return 0;
> > >  }
> > >
> > >  static int opts_do_parse(QemuOpts *opts, const char *params,
> > > --
> > > 1.7.12.4
> > >
> >
> >
diff mbox

Patch

diff --git a/include/qemu/option.h b/include/qemu/option.h
index 8c0ac34..c3b0a91 100644
--- a/include/qemu/option.h
+++ b/include/qemu/option.h
@@ -99,6 +99,7 @@  typedef struct QemuOptDesc {
     const char *name;
     enum QemuOptType type;
     const char *help;
+    const char *def_value_str;
 } QemuOptDesc;
 
 struct QemuOptsList {
@@ -156,7 +157,7 @@  QDict *qemu_opts_to_qdict(QemuOpts *opts, QDict *qdict);
 void qemu_opts_absorb_qdict(QemuOpts *opts, QDict *qdict, Error **errp);
 
 typedef int (*qemu_opts_loopfunc)(QemuOpts *opts, void *opaque);
-int qemu_opts_print(QemuOpts *opts, void *dummy);
+void qemu_opts_print(QemuOpts *opts);
 int qemu_opts_foreach(QemuOptsList *list, qemu_opts_loopfunc func, void *opaque,
                       int abort_on_failure);
 
diff --git a/util/qemu-option.c b/util/qemu-option.c
index e6d10bc..d5e80da 100644
--- a/util/qemu-option.c
+++ b/util/qemu-option.c
@@ -570,6 +570,13 @@  static QemuOpt *qemu_opt_find(QemuOpts *opts, const char *name)
 const char *qemu_opt_get(QemuOpts *opts, const char *name)
 {
     QemuOpt *opt = qemu_opt_find(opts, name);
+
+    if (!opt) {
+        const QemuOptDesc *desc = find_desc_by_name(opts->list->desc, name);
+        if (desc && desc->def_value_str) {
+            return desc->def_value_str;
+        }
+    }
     return opt ? opt->str : NULL;
 }
 
@@ -589,8 +596,13 @@  bool qemu_opt_get_bool(QemuOpts *opts, const char *name, bool defval)
 {
     QemuOpt *opt = qemu_opt_find(opts, name);
 
-    if (opt == NULL)
+    if (opt == NULL) {
+        const QemuOptDesc *desc = find_desc_by_name(opts->list->desc, name);
+        if (desc && desc->def_value_str) {
+            parse_option_bool(name, desc->def_value_str, &defval, &error_abort);
+        }
         return defval;
+    }
     assert(opt->desc && opt->desc->type == QEMU_OPT_BOOL);
     return opt->value.boolean;
 }
@@ -599,8 +611,14 @@  uint64_t qemu_opt_get_number(QemuOpts *opts, const char *name, uint64_t defval)
 {
     QemuOpt *opt = qemu_opt_find(opts, name);
 
-    if (opt == NULL)
+    if (opt == NULL) {
+        const QemuOptDesc *desc = find_desc_by_name(opts->list->desc, name);
+        if (desc && desc->def_value_str) {
+            parse_option_number(name, desc->def_value_str, &defval,
+                                &error_abort);
+        }
         return defval;
+    }
     assert(opt->desc && opt->desc->type == QEMU_OPT_NUMBER);
     return opt->value.uint;
 }
@@ -609,8 +627,13 @@  uint64_t qemu_opt_get_size(QemuOpts *opts, const char *name, uint64_t defval)
 {
     QemuOpt *opt = qemu_opt_find(opts, name);
 
-    if (opt == NULL)
+    if (opt == NULL) {
+        const QemuOptDesc *desc = find_desc_by_name(opts->list->desc, name);
+        if (desc && desc->def_value_str) {
+            parse_option_size(name, desc->def_value_str, &defval, &error_abort);
+        }
         return defval;
+    }
     assert(opt->desc && opt->desc->type == QEMU_OPT_SIZE);
     return opt->value.uint;
 }
@@ -895,17 +918,32 @@  void qemu_opts_del(QemuOpts *opts)
     g_free(opts);
 }
 
-int qemu_opts_print(QemuOpts *opts, void *dummy)
+void qemu_opts_print(QemuOpts *opts)
 {
     QemuOpt *opt;
+    QemuOptDesc *desc = opts->list->desc;
 
-    fprintf(stderr, "%s: %s:", opts->list->name,
-            opts->id ? opts->id : "<noid>");
-    QTAILQ_FOREACH(opt, &opts->head, next) {
-        fprintf(stderr, " %s=\"%s\"", opt->name, opt->str);
+    if (desc[0].name == NULL) {
+        QTAILQ_FOREACH(opt, &opts->head, next) {
+            fprintf(stderr, "%s=\"%s\" ", opt->name, opt->str);
+        }
+        return;
+    }
+    for (; desc && desc->name; desc++) {
+        const char *value;
+        QemuOpt *opt = qemu_opt_find(opts, desc->name);
+
+        value = opt ? opt->str : desc->def_value_str;
+        if (!value) {
+            continue;
+        }
+        if (desc->type == QEMU_OPT_STRING) {
+            fprintf(stderr, "%s='%s' ", desc->name, value);
+        } else {
+            fprintf(stderr, "%s=%s ", desc->name, value);
+        }
     }
     fprintf(stderr, "\n");
-    return 0;
 }
 
 static int opts_do_parse(QemuOpts *opts, const char *params,