81 lines
2.6 KiB
C
81 lines
2.6 KiB
C
/*
|
|
* linux/ioctl.h for Linux by H.H. Bergman.
|
|
*/
|
|
|
|
#ifndef _ASM_IOCTL_H
|
|
#define _ASM_IOCTL_H
|
|
|
|
/* ioctl command encoding: 32 bits total, command in lower 16 bits,
|
|
* size of the parameter structure in the lower 14 bits of the
|
|
* upper 16 bits.
|
|
* Encoding the size of the parameter structure in the ioctl request
|
|
* is useful for catching programs compiled with old versions
|
|
* and to avoid overwriting user space outside the user buffer area.
|
|
* The highest 2 bits are reserved for indicating the ``access mode''.
|
|
* NOTE: This limits the max parameter size to 16kB -1 !
|
|
*/
|
|
|
|
/*
|
|
* I don't really have any idea about what this should look like, so
|
|
* for the time being, this is heavily based on the PC definitions.
|
|
*/
|
|
|
|
/*
|
|
* The following is for compatibility across the various Linux
|
|
* platforms. The i386 ioctl numbering scheme doesn't really enforce
|
|
* a type field. De facto, however, the top 8 bits of the lower 16
|
|
* bits are indeed used as a type field, so we might just as well make
|
|
* this explicit here. Please be sure to use the decoding macros
|
|
* below from now on.
|
|
*/
|
|
#define _IOC_NRBITS 8
|
|
#define _IOC_TYPEBITS 8
|
|
#define _IOC_SIZEBITS 14
|
|
#define _IOC_DIRBITS 2
|
|
|
|
#define _IOC_NRMASK ((1 << _IOC_NRBITS)-1)
|
|
#define _IOC_TYPEMASK ((1 << _IOC_TYPEBITS)-1)
|
|
#define _IOC_SIZEMASK ((1 << _IOC_SIZEBITS)-1)
|
|
#define _IOC_DIRMASK ((1 << _IOC_DIRBITS)-1)
|
|
|
|
#define _IOC_NRSHIFT 0
|
|
#define _IOC_TYPESHIFT (_IOC_NRSHIFT+_IOC_NRBITS)
|
|
#define _IOC_SIZESHIFT (_IOC_TYPESHIFT+_IOC_TYPEBITS)
|
|
#define _IOC_DIRSHIFT (_IOC_SIZESHIFT+_IOC_SIZEBITS)
|
|
|
|
/*
|
|
* Direction bits.
|
|
*/
|
|
#define _IOC_NONE 0U
|
|
#define _IOC_WRITE 1U
|
|
#define _IOC_READ 2U
|
|
|
|
#define _IOC(dir,type,nr,size) \
|
|
(((dir) << _IOC_DIRSHIFT) | \
|
|
((type) << _IOC_TYPESHIFT) | \
|
|
((nr) << _IOC_NRSHIFT) | \
|
|
((size) << _IOC_SIZESHIFT))
|
|
|
|
/* used to create numbers */
|
|
#define _IO(type,nr) _IOC(_IOC_NONE,(type),(nr),0)
|
|
#define _IOR(type,nr,size) _IOC(_IOC_READ,(type),(nr),sizeof(size))
|
|
#define _IOW(type,nr,size) _IOC(_IOC_WRITE,(type),(nr),sizeof(size))
|
|
#define _IOWR(type,nr,size) _IOC(_IOC_READ|_IOC_WRITE,(type),(nr),sizeof(size))
|
|
|
|
/* used to decode ioctl numbers.. */
|
|
#define _IOC_DIR(nr) (((nr) >> _IOC_DIRSHIFT) & _IOC_DIRMASK)
|
|
#define _IOC_TYPE(nr) (((nr) >> _IOC_TYPESHIFT) & _IOC_TYPEMASK)
|
|
#define _IOC_NR(nr) (((nr) >> _IOC_NRSHIFT) & _IOC_NRMASK)
|
|
#define _IOC_SIZE(nr) (((nr) >> _IOC_SIZESHIFT) & _IOC_SIZEMASK)
|
|
|
|
/* ...and for the drivers/sound files... */
|
|
|
|
#define IOC_IN (_IOC_WRITE << _IOC_DIRSHIFT)
|
|
#define IOC_OUT (_IOC_READ << _IOC_DIRSHIFT)
|
|
#define IOC_INOUT ((_IOC_WRITE|_IOC_READ) << _IOC_DIRSHIFT)
|
|
#define IOCSIZE_MASK (_IOC_SIZEMASK << _IOC_SIZESHIFT)
|
|
#define IOCSIZE_SHIFT (_IOC_SIZESHIFT)
|
|
|
|
#endif /* _ASM_IOCTL_H */
|
|
|