Re: [TWAIN] Reconcile sane's long names to TWAIN's 32 byte limit

[Robert Shearman]

Jeremy White wrote:
> libsane can return arbitrarily long names, but TWAIN supports only a maximum of 32.
> Further, the name is a unique identifier, and so must be returned to libsane for processing.
>
> This algorithm tries to convert a long libsane name into a more reasonable short name,
> but adds a crude signature process in an attempt to ensure a unique short identifier.
>
> dlls/twain/dsm_ctrl.c |   85 ++++++++++++++++++++++++++++++++++++++++++-------
> 1 files changed, 73 insertions(+), 12 deletions(-)
>
> eabadf1c3584adda1a36b199f82bc6bbb17b71da
> diff --git a/dlls/twain/dsm_ctrl.c b/dlls/twain/dsm_ctrl.c
> index f744939..6d1318d 100644
> --- a/dlls/twain/dsm_ctrl.c
> +++ b/dlls/twain/dsm_ctrl.c
> @@ -22,6 +22,7 @@
>
> #include <stdlib.h>
> #include <stdarg.h>
> +#include <stdio.h>
>
> #define NONAMELESSUNION
> #define NONAMELESSSTRUCT
> @@ -33,6 +34,14 @@
>
> WINE_DEFAULT_DEBUG_CHANNEL(twain);
>
> +inline static LPSTR TWAIN_strdup( LPCSTR str )
> +{
> - LPSTR ret = HeapAlloc( GetProcessHeap(), 0, strlen(str) + 1 );
> - if (ret) strcpy( ret, str );
> - return ret;
>
> +}
> -
> -
>
> /* DG_CONTROL/DAT_IDENTITY/MSG_CLOSEDS */
> TW_UINT16 TWAIN_CloseDS (pTW_IDENTITY pOrigin, TW_MEMREF pData)
> {
> @@ -83,6 +92,38 @@ TW_UINT16 TWAIN_CloseDS (pTW_IDENTITY pO
> #endif
> }
>
> +/* Sane returns device names that are longer than the 32 bytes allowed
> - by TWAIN.  However, it colon separates them, and the last bit is
> - the most interesting.  So we use the last bit, and add a signature
> - to ensure uniqueness */
>
> +static char * get_sane_short_name(const char *in)
> +{
> - char *p;
> - LPSTR ret;
> - int  signature = 0;
> -
> - if (strlen(in) <= 32)
> -
>    return TWAIN_strdup((char *) in);
> -
> - for (p = (char *) in; *p; p++)
> -
>    signature += *p;

These casts from const char * to char * shouldn't be necessary.

[TWAIN] Reconcile sane's long names to TWAIN's 32 byte limit

[Robert Shearman]

Robert Shearman wrote:
> Jeremy White wrote:
> > libsane can return arbitrarily long names, but TWAIN supports only a 
> > maximum of 32.
> > Further, the name is a unique identifier, and so must be returned to 
> > libsane for processing.
> >
> > This algorithm tries to convert a long libsane name into a more 
> > reasonable short name,
> > but adds a crude signature process in an attempt to ensure a unique 
> > short identifier.
> >
> > dlls/twain/dsm_ctrl.c |   85 
> > ++++++++++++++++++++++++++++++++++++++++++-------
> > 1 files changed, 73 insertions(+), 12 deletions(-)
> >
> > eabadf1c3584adda1a36b199f82bc6bbb17b71da
> > diff --git a/dlls/twain/dsm_ctrl.c b/dlls/twain/dsm_ctrl.c
> > index f744939..6d1318d 100644
> > --- a/dlls/twain/dsm_ctrl.c
> > +++ b/dlls/twain/dsm_ctrl.c
> > @@ -22,6 +22,7 @@
> >
> > #include <stdlib.h>
> > #include <stdarg.h>
> > +#include <stdio.h>
> >
> > #define NONAMELESSUNION
> > #define NONAMELESSSTRUCT
> > @@ -33,6 +34,14 @@
> >
> > WINE_DEFAULT_DEBUG_CHANNEL(twain);
> >
> > +inline static LPSTR TWAIN_strdup( LPCSTR str )
> > +{
> > - LPSTR ret = HeapAlloc( GetProcessHeap(), 0, strlen(str) + 1 );
> > - if (ret) strcpy( ret, str );
> > - return ret;
> >
> > +}
> > -
> > -
> >
> > /* DG_CONTROL/DAT_IDENTITY/MSG_CLOSEDS */
> > TW_UINT16 TWAIN_CloseDS (pTW_IDENTITY pOrigin, TW_MEMREF pData)
> > {
> > @@ -83,6 +92,38 @@ TW_UINT16 TWAIN_CloseDS (pTW_IDENTITY pO
> > #endif
> > }
> >
> > +/* Sane returns device names that are longer than the 32 bytes allowed
> > - by TWAIN.  However, it colon separates them, and the last bit is
> > - the most interesting.  So we use the last bit, and add a signature
> > - to ensure uniqueness */
> >
> > +static char * get_sane_short_name(const char *in)
> > +{
> > - char *p;
> > - LPSTR ret;
> > - int  signature = 0;
> > -
> > - if (strlen(in) <= 32)
> > -
> >    return TWAIN_strdup((char *) in);
> > -
> > - for (p = (char *) in; *p; p++)
> > -
> >    signature += *p;
>
> These casts from const char * to char * shouldn't be necessary.

See attached patch.