/* ports.h - isbadport */

#define NPORTS          30              /* Maximum number of ports      */
#define PT_MSGS         100             /* Total messages in system     */
#define PT_FREE         1               /* Port is free                 */
#define PT_LIMBO        2               /* Port is being deleted/reset  */
#define PT_ALLOC        3               /* Port is allocated            */

struct  ptnode  {                       /* Node on list of messages     */
        uint32  ptmsg;                  /* A one-word message           */
        struct  ptnode  *ptnext;        /* Pointer to next node on list */
};

struct  ptentry {                       /* Entry in the port table      */
        sid32   ptssem;                 /* Sender semaphore             */
        sid32   ptrsem;                 /* Receiver semaphore           */
        uint16  ptstate;                /* Port state (FREE/LIMBO/ALLOC)*/
        uint16  ptmaxcnt;               /* Max messages to be queued    */
        int32   ptseq;                  /* Sequence changed at creation */
        struct  ptnode  *pthead;        /* List of message pointers     */
        struct  ptnode  *pttail;        /* Tail of message list         */
};

extern  struct  ptnode  *ptfree;        /* List of free nodes           */
extern  struct  ptentry porttab[];      /* Port table                   */
extern  int32   ptnextid;               /* Next port ID to try when     */
                                        /*   looking for a free slot    */

#define isbadport(portid)       ( (portid)<0 || (portid)>=NPORTS )