Re: [Qemu-devel] [PATCH RFC 18/21] qapi/common: Fix guardname() for funny filenames

[Eric Blake]

On 02/02/2018 07:03 AM, Markus Armbruster wrote:
> guardname() fails to return a valid C identifier for arguments
> containing anything but [A-Za-z0-9_.-'].  Fix that.
>
> Signed-off-by: Markus Armbruster <address@hidden>
> ---
>   scripts/qapi/common.py | 2 +-
>   1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/scripts/qapi/common.py b/scripts/qapi/common.py
> index 7ffffc78d9..7d497b5b17 100644
> --- a/scripts/qapi/common.py
> +++ b/scripts/qapi/common.py
> @@ -1860,7 +1860,7 @@ def mcgen(code, **kwds):
>   
>   
>   def guardname(filename):
> -    return c_name(filename, protect=False).upper()
> +    return re.sub(r'[^A-Za-z0-9_]', '_', filename).upper()

For some choices of filename, the old code prefixes a q_ (via c_name) 
which gets turned into Q_ in the final guard name.  The new code does 
not.  Then again, all of the names protected by c_name() all contain 
lower case, while guard names are all upper case; so we aren't 
protecting ourselves from defining a reserved word; the main use for 
c_name() is to protect ourselves where we are not changing case (for 
example, _BOOL is no better than Q__BOOL as a guard name for a file 
named _Bool).

Might be worth mentioning this design consideration in the commit 
message, but the change itself is reasonable.

Reviewed-by: Eric Blake <address@hidden>

--
Eric Blake, Principal Software Engineer
Red Hat, Inc.           +1-919-301-3266
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