ref: f0b565742993646ac2c7939e3a89f44c2515fbe6
dir: /os/boot/pc/etherif.h/
typedef struct RingBuf { uchar owner; uchar unused; ushort len; uchar pkt[sizeof(Etherpkt)]; } RingBuf; enum { Host = 0, /* buffer owned by host */ Interface = 1, /* buffer owned by card */ Nrb = 32, /* default number of receive buffers */ Ntb = 8, /* default number of transmit buffers */ }; typedef struct Ether Ether; struct Ether { ISAConf; /* hardware info */ int ctlrno; int state; /* 0: unfound, 1: found, 2: attaching */ int tbdf; void (*attach)(Ether*); /* filled in by reset routine */ void (*transmit)(Ether*); void (*interrupt)(Ureg*, void*); void (*detach)(Ether*); void *ctlr; ushort nrb; /* number of software receive buffers */ ushort ntb; /* number of software transmit buffers */ RingBuf *rb; /* software receive buffers */ RingBuf *tb; /* software transmit buffers */ ushort rh; /* first receive buffer belonging to host */ ushort ri; /* first receive buffer belonging to card */ ushort th; /* first transmit buffer belonging to host */ ushort ti; /* first transmit buffer belonging to card */ int tbusy; /* transmitter is busy */ int mbps; /* zero means link down */ }; extern void etherrloop(Ether*, Etherpkt*, long); extern void addethercard(char*, int(*)(Ether*)); #define NEXT(x, l) (((x)+1)%(l)) #define PREV(x, l) (((x) == 0) ? (l)-1: (x)-1)