/* mkbufpool.c - mkbufpool */

#include 

/*------------------------------------------------------------------------
 *  mkbufpool  -  Allocate memory for a buffer pool and link the buffers
 *------------------------------------------------------------------------
 */
bpid32  mkbufpool(
          int32         bufsiz,         /* Size of a buffer in the pool */
          int32         numbufs         /* Number of buffers in the pool*/
        )
{
        intmask mask;                   /* Saved interrupt mask         */
        bpid32  poolid;                 /* ID of pool that is created   */
        struct  bpentry *bpptr;         /* Pointer to entry in buftab   */
        char    *buf;                   /* Pointer to memory for buffer */

        mask = disable();
        if (bufsizBP_MAXB
            || numbufs<1 || numbufs>BP_MAXN
            || nbpools >= NBPOOLS) {
                restore(mask);
                return (bpid32)SYSERR;
        }
        /* Round request to a multiple of 4 bytes */

        bufsiz = ( (bufsiz + 3) & (~3) );

        /* Increase buffer size to include a pool ID */

        bufsiz += sizeof(bpid32);
        buf = (char *)getmem( numbufs * bufsiz );
        if ((int32)buf == SYSERR) {
                restore(mask);
                return (bpid32)SYSERR;
        }
        poolid = nbpools++;
        bpptr = &buftab[poolid];
        bpptr->bpnext = (struct bpentry *)buf;
        if ( (bpptr->bpsem = semcreate(numbufs)) == SYSERR) {
                freemem(buf, numbufs * bufsiz );
                nbpools--;
                restore(mask);
                return (bpid32)SYSERR;
        }
        for (numbufs-- ; numbufs>0 ; numbufs-- ) {
                bpptr = (struct bpentry *)buf;
                buf += bufsiz;
                bpptr->bpnext = (struct bpentry *)buf;
        }
        bpptr = (struct bpentry *)buf;
        bpptr->bpnext = (struct bpentry *)NULL;
        restore(mask);
        return poolid;
}