Re: [Qemu-devel] [PATCH v2 1/4] vl.c: Fix regression in machine error message

[Markus Armbruster]

Markus Armbruster <address@hidden> writes:

> Marcel Apfelbaum <address@hidden> writes:
>
>> On 02/15/2016 12:20 PM, Markus Armbruster wrote:
>>> Eduardo Habkost <address@hidden> writes:
>>>
>>>> From: Marcel Apfelbaum <address@hidden>
>>>>
>>>> Commit e1ce0c3cb (vl.c: fix regression when reading machine type
>>>> from config file) fixed the error message when the machine type
>>>> was supplied inside the config file. However now the option name
>>>> is not displayed correctly if the error happens when the machine
>>>> is specified at command line.
>>>>
>>>> Running
>>>>      ./x86_64-softmmu/qemu-system-x86_64 -M q35-1.5 -redir tcp:8022::22
>>>> will result in the error message:
>>>>      qemu-system-x86_64: -redir tcp:8022::22: unsupported machine type
>>>>      Use -machine help to list supported machines
>>>>
>>>> Fixed it by restoring the error location and also extracted the code
>>>> dealing with machine options into a separate function.
>>>>
>>>> Reported-by: Michael S. Tsirkin <address@hidden>
>>>> Reviewed-by: Laszlo Ersek <address@hidden>
>>>> Signed-off-by: Marcel Apfelbaum <address@hidden>
>>>> Reviewed-by: Eduardo Habkost <address@hidden>
>>>> Signed-off-by: Eduardo Habkost <address@hidden>
>>>> ---
>>>>   vl.c | 37 ++++++++++++++++++++++++++-----------
>>>>   1 file changed, 26 insertions(+), 11 deletions(-)
>>>>
>>>> diff --git a/vl.c b/vl.c
>>>> index 175ebcc..afbf13f 100644
>>>> --- a/vl.c
>>>> +++ b/vl.c
>>>> @@ -2748,6 +2748,31 @@ static const QEMUOption *lookup_opt(int argc, char 
>>>> **argv,
>>>>       return popt;
>>>>   }
>>>>
>>>> +static void set_machine_options(MachineClass **machine_class)
>>>> +{
>>>> +    const char *optarg;
>>>> +    QemuOpts *opts;
>>>> +    Location loc;
>>>> +
>>>> +    loc_push_none(&loc);
>>>> +
>>>> +    opts = qemu_get_machine_opts();
>>>> +    qemu_opts_loc_restore(opts);
>>>> +
>>>> +    optarg = qemu_opt_get(opts, "type");
>>>> +    if (optarg) {
>>>> +        *machine_class = machine_parse(optarg);
>>>> +    }
>>>> +
>>>> +    if (*machine_class == NULL) {
>>>> +        error_report("No machine specified, and there is no default");
>>>> +        error_printf("Use -machine help to list supported machines\n");
>>>> +        exit(1);
>>>> +    }
>>>> +
>>>> +    loc_pop(&loc);
>>>> +}
>>>> +
>>>>   static int machine_set_property(void *opaque,
>>>>                                   const char *name, const char *value,
>>>>                                   Error **errp)
>>>> @@ -4030,17 +4055,7 @@ int main(int argc, char **argv, char **envp)
>>>>
>>>>       replay_configure(icount_opts);
>>>>
>>>> -    opts = qemu_get_machine_opts();
>>>> -    optarg = qemu_opt_get(opts, "type");
>>>> -    if (optarg) {
>>>> -        machine_class = machine_parse(optarg);
>>>> -    }
>>>> -
>>>> -    if (machine_class == NULL) {
>>>> -        error_report("No machine specified, and there is no default");
>>>> -        error_printf("Use -machine help to list supported machines\n");
>>>> -        exit(1);
>>>> -    }
>>>> +    set_machine_options(&machine_class);
>>>
>>> Style nit: I'd prefer
>>>
>>>      machine_class = parse_machine_options();

Uh, set_machine_options() also reads machine_class, so this won't do.

Better:

         machine_class = pick_machine(find_default_machine());

but that's a bit more than what I'm willing to do on commit.  I'll post
a follow-up patch.

[...]