Re: [Qemu-devel] [PATCH 13/22] add visitor for parsing hz[KMG] input string

[Don Slutz <Don@CloudSwitch.Com>]

On 09/07/12 18:47, Igor Mammedov wrote:
> On Fri, 7 Sep 2012 18:12:00 -0400
> Don Slutz <Don@cloudswitch.com> wrote:
>
>> On 09/07/12 16:55, Igor Mammedov wrote:
>>> Signed-off-by: Igor Mammedov <imammedo@redhat.com>
>>> Acked-by: Andreas Färber <afaerber@suse.de>
>>> --
>>> v2:
>>>     * replaced _hz suffix for frequency visitor by _freq suffix
>>>       suggested-by: Andreas Färber
>>>     * fixed typo & extra space spotted-by: Andreas Färber
>>> ---
>>>    qapi/qapi-visit-core.c      | 11 +++++++++++
>>>    qapi/qapi-visit-core.h      |  2 ++
>>>    qapi/string-input-visitor.c | 22 ++++++++++++++++++++++
>>>    3 files changed, 35 insertions(+)
>>>
>>> diff --git a/qapi/qapi-visit-core.c b/qapi/qapi-visit-core.c
>>> index 7a82b63..5c8705e 100644
>>> --- a/qapi/qapi-visit-core.c
>>> +++ b/qapi/qapi-visit-core.c
>>> @@ -311,3 +311,14 @@ void input_type_enum(Visitor *v, int *obj, const char *strings[],
>>>        g_free(enum_str);
>>>        *obj = value;
>>>    }
>>> +
>>> +void visit_type_freq(Visitor *v, int64_t *obj, const char *name, Error **errp)
>>> +{
>>> +    if (!error_is_set(errp)) {
>>> +        if (v->type_freq) {
>>> +            v->type_freq(v, obj, name, errp);
>>> +        } else {
>>> +            v->type_int(v, obj, name, errp);
>>> +        }
>>> +    }
>>> +}
>>> diff --git a/qapi/qapi-visit-core.h b/qapi/qapi-visit-core.h
>>> index 60aceda..e5e7dd7 100644
>>> --- a/qapi/qapi-visit-core.h
>>> +++ b/qapi/qapi-visit-core.h
>>> @@ -62,6 +62,7 @@ struct Visitor
>>>        void (*type_int64)(Visitor *v, int64_t *obj, const char *name, Error **errp);
>>>        /* visit_type_size() falls back to (*type_uint64)() if type_size is unset */
>>>        void (*type_size)(Visitor *v, uint64_t *obj, const char *name, Error **errp);
>>> +    void (*type_freq)(Visitor *v, int64_t *obj, const char *name, Error **errp);
>>>    };
>>>    
>>>    void visit_start_handle(Visitor *v, void **obj, const char *kind,
>>> @@ -91,5 +92,6 @@ void visit_type_size(Visitor *v, uint64_t *obj, const char *name, Error **errp);
>>>    void visit_type_bool(Visitor *v, bool *obj, const char *name, Error **errp);
>>>    void visit_type_str(Visitor *v, char **obj, const char *name, Error **errp);
>>>    void visit_type_number(Visitor *v, double *obj, const char *name, Error **errp);
>>> +void visit_type_freq(Visitor *v, int64_t *obj, const char *name, Error **errp);
>>>    
>>>    #endif
>>> diff --git a/qapi/string-input-visitor.c b/qapi/string-input-visitor.c
>>> index 497eb9a..47d2a84 100644
>>> --- a/qapi/string-input-visitor.c
>>> +++ b/qapi/string-input-visitor.c
>>> @@ -110,6 +110,27 @@ static void parse_start_optional(Visitor *v, bool *present,
>>>        *present = true;
>>>    }
>>>    
>>> +static void parse_type_freq(Visitor *v, int64_t *obj, const char *name,
>>> +                            Error **errp)
>>> +{
>>> +    StringInputVisitor *siv = DO_UPCAST(StringInputVisitor, visitor, v);
>>> +    char *endp = (char *) siv->string;
>>> +    long long val;
>> I get:
>>
>> cc1: warnings being treated as errors
>> qapi/string-input-visitor.c: In function 'parse_type_freq':
>> qapi/string-input-visitor.c:118: error: 'val' may be used uninitialized
>> in this function
>> make: *** [qapi/string-input-visitor.o] Error 1
>> make: *** Waiting for unfinished jobs....
> FC17 with default configure settings doesn't complain.
> And I really do not see how it could be.
>
>> Which the change:
>>
>>
>> diff --git a/qapi/string-input-visitor.c b/qapi/string-input-visitor.c
>> index 47d2a84..74fe395 100644
>> --- a/qapi/string-input-visitor.c
>> +++ b/qapi/string-input-visitor.c
>> @@ -115,7 +115,7 @@ static void parse_type_freq(Visitor *v, int64_t
>> *obj, const char *name,
>>    {
>>        StringInputVisitor *siv = DO_UPCAST(StringInputVisitor, visitor, v);
>>        char *endp = (char *) siv->string;
>> -    long long val;
>> +    long long val = 0;
>>        errno = 0;
>>        if (siv->string) {
>>
>> Fixes it for me.
>>
>>> +
>>> +    errno = 0;
>>> +    if (siv->string) {
>>> +        val = strtosz_suffix_unit(siv->string, &endp,
>>> +                             STRTOSZ_DEFSUFFIX_B, 1000);
>>> +    }
>>> +    if (!siv->string || val == -1 || *endp) {
I am using CentOS 6.3 so a different compiler.  This is the line that 
has the issue.

If !siv->string is true the 1st if does not set val. val is then checked 
for -1.

>>> +        error_set(errp, QERR_INVALID_PARAMETER_VALUE, name,
>>> +              "a value representable as a non-negative int64");
>>> +        return;
>>> +    }
>>> +
>>> +    *obj = val;
>>> +}
>>> +
>>>    Visitor *string_input_get_visitor(StringInputVisitor *v)
>>>    {
>>>        return &v->visitor;
>>> @@ -132,6 +153,7 @@ StringInputVisitor *string_input_visitor_new(const char *str)
>>>        v->visitor.type_str = parse_type_str;
>>>        v->visitor.type_number = parse_type_number;
>>>        v->visitor.start_optional = parse_start_optional;
>>> +    v->visitor.type_freq = parse_type_freq;
>>>    
>>>        v->string = str;
>>>        return v;
>>     -Don Slutz
>
   -Don Slutz