Re: [Qemu-devel] [PATCH 1/3] qdev: Add help for device properties

[Markus Armbruster <armbru@redhat.com>]

Markus Armbruster <armbru@redhat.com> writes:

> Stefan Weil <weil@mail.berlios.de> writes:
>
>> When called with property "?", a list of supported
>> properties will be printed (instead of an error message).
>>
>> This is useful for command lines like
>> 	qemu -device e1000,?
>> and was already standard for other options like model=?
>>
>> Signed-off-by: Stefan Weil <weil@mail.berlios.de>
>> ---
>>  hw/qdev-properties.c |   15 +++++++++++++--
>>  1 files changed, 13 insertions(+), 2 deletions(-)
>>
>> diff --git a/hw/qdev-properties.c b/hw/qdev-properties.c
>> index 277ff9e..8547ad2 100644
>> --- a/hw/qdev-properties.c
>> +++ b/hw/qdev-properties.c
>> @@ -544,8 +544,19 @@ int qdev_prop_parse(DeviceState *dev, const char *name, const char *value)
>>  
>>      prop = qdev_prop_find(dev, name);
>>      if (!prop) {
>> -        fprintf(stderr, "property \"%s.%s\" not found\n",
>> -                dev->info->name, name);
>> +        if (strcmp(name, "?") != 0) {
>> +            fprintf(stderr, "property \"%s.%s\" not found\n",
>> +                    dev->info->name, name);
>> +        } else {
>> +            fprintf(stderr, "supported properties:\n");
>> +            if (dev->info->props != NULL) {
>> +                Property *props = dev->info->props;
>> +                while (props->name) {
>> +                    fprintf(stderr, "%s.%s\n", dev->info->name, props->name);
>> +                    props++;
>> +                }
>> +            }
>> +        }
>>          return -1;
>>      }
>>      if (!prop->info->parse) {
>
> I like it.

One question, though: why print DRIVER.PROPNAME instead of just
PROPNAME?  You could still put DRIVER into the heading, say "Properties
of DRIVER:".