[sane-devel] [patch] fix SANE_Device

[Frank Zago]

Frank Zago wrote:
>=20
>>
>> The SANE standard defines the comunication between frontend and backen=
d.
>> It does not define any structs that shall be internally used by the
>> frontend or backend.
>>
>> I think the clean appoach is that the backend handles the texts intern=
al
>> as non const strings and only creats the SANE_Device struct to return
>> the data to the frontend. The SANE_Device struct is defined for the
>> purpose to transfer the data from the backend to the frontend as const
>> chars. When the backend has to use non const definitions then it is no=
t
>> allowed to use the SANE_Device struct so it has to use it=C2=B4s own d=
ata
>> types and not the one of the SANE standard.
>>
>> Oliver
>=20
>=20
> So, in that case what about the patch in attachment.
>=20
> I've also changed the internal definition of SANE_Option_Descriptor for=
=20
> the same  reason. It breaks about 5 backends, but they can all be easil=
y=20
> fixed by hand by removing a few const. I'd say that the current=20
> definition of SANE_Device and SANE_Option_Descriptor and created an ugl=
y=20
> cascade of unnecessary casts and consts in all the backends.
>=20
> Frank.
>=20
>=20
>=20
> -----------------------------------------------------------------------=
-
>=20
> Index: include/sane/sane.h
> =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=
=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=
=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D
> RCS file: /cvsroot/sane/sane-backends/include/sane/sane.h,v
> retrieving revision 1.6
> diff -u -3 -p -B -b -u -r1.6 sane.h
> --- include/sane/sane.h	13 Nov 2004 20:29:14 -0000	1.6
> +++ include/sane/sane.h	14 Nov 2004 18:59:03 -0000
> @@ -92,6 +92,16 @@ typedef enum
>    }
>  SANE_Unit;
> =20
> +#ifdef BACKEND_NAME
> +typedef struct
> +  {
> +    SANE_String name;	/* unique device name */
> +    SANE_String vendor;	/* device vendor string */
> +    SANE_String model;	/* device model name */
> +    SANE_String type;	/* device type (e.g., "flatbed scanner") */
> +  }
> +SANE_Device;
> +#else
>  typedef struct
>    {
>      SANE_String_Const name;	/* unique device name */
> @@ -100,6 +110,7 @@ typedef struct
>      SANE_String_Const type;	/* device type (e.g., "flatbed scanner") *=
/
>    }
>  SANE_Device;
> +#endif
> =20
>  #define SANE_CAP_SOFT_SELECT		(1 << 0)
>  #define SANE_CAP_HARD_SELECT		(1 << 1)
> @@ -134,6 +145,28 @@ typedef struct
>    }
>  SANE_Range;
> =20
> +#ifdef BACKEND_NAME
> +typedef struct
> +  {
> +    SANE_String name;	/* name of this option (command-line name) */
> +    SANE_String title;	/* title of this option (single-line) */
> +    SANE_String desc;	/* description of this option (multi-line) */
> +    SANE_Value_Type type;	/* how are values interpreted? */
> +    SANE_Unit unit;		/* what is the (physical) unit? */
> +    SANE_Int size;
> +    SANE_Int cap;		/* capabilities */
> +
> +    SANE_Constraint_Type constraint_type;
> +    union
> +      {
> +	SANE_String *string_list;	/* NULL-terminated list */
> +	SANE_Word *word_list;	/* first element is list-length */
> +	SANE_Range *range;
> +      }
> +    constraint;
> +  }
> +SANE_Option_Descriptor;
> +#else
>  typedef struct
>    {
>      SANE_String_Const name;	/* name of this option (command-line name)=
 */
> @@ -154,6 +187,7 @@ typedef struct
>      constraint;
>    }
>  SANE_Option_Descriptor;
> +#endif
> =20
>  typedef enum
>    {



SO? Is anyone for or against this patch?