#include <linux/stddef.h>
#include "mhshmkern.h"

#define mhshm_diverter_sysnum 253
#define attach_funnum 0
#define create_funnum 1
#define detach_funnum 2
#define getmod_funnum 3

extern int errno;

inline long mhshm_diverter (int funnum, long l, void *p)
{
        long ret;

        /* repris de /usr/include/asm/unistd.h:_syscall3 */
        __asm__ volatile (
             "int   $0x80; "
             : "=a" (ret) 
             : "0" (mhshm_diverter_sysnum), "b" ((long)funnum),
             "c" ((long)l), "d" ((long)p)
        );
        if (ret < 0) {
                errno = -ret;
                ret = -1;
        }
        return ret;
}

long mhshm_attach (long id, unsigned char **raddr)
{
        return mhshm_diverter (attach_funnum, id, (void *)raddr);
}

long mhshm_create (long id, unsigned char **raddr)
{
        return mhshm_diverter (create_funnum, id, (void *)raddr);
}

long mhshm_detach (unsigned char *shmaddr)
{
        return mhshm_diverter (detach_funnum, 0, (void *)shmaddr);
}

long mhshm_getmod (long id, struct mhshm_kern_mod *ptr)
{
        return mhshm_diverter (getmod_funnum, id, (void *)ptr);
}