| 1 | /* |
| 2 | * Copyright (c) University of British Columbia, 1984 |
| 3 | * Copyright (c) 1990 The Regents of the University of California. |
| 4 | * All rights reserved. |
| 5 | * |
| 6 | * This code is derived from software contributed to Berkeley by |
| 7 | * the Laboratory for Computation Vision and the Computer Science Department |
| 8 | * of the University of British Columbia. |
| 9 | * |
| 10 | * %sccs.include.redist.c% |
| 11 | * |
| 12 | * @(#)hd_timer.c 7.4 (Berkeley) %G% |
| 13 | */ |
| 14 | |
| 15 | #include "param.h" |
| 16 | #include "systm.h" |
| 17 | #include "mbuf.h" |
| 18 | #include "domain.h" |
| 19 | #include "socket.h" |
| 20 | #include "protosw.h" |
| 21 | #include "errno.h" |
| 22 | #include "time.h" |
| 23 | #include "kernel.h" |
| 24 | |
| 25 | #include "../net/if.h" |
| 26 | |
| 27 | #include "hdlc.h" |
| 28 | #include "hd_var.h" |
| 29 | #include "x25.h" |
| 30 | |
| 31 | /* |
| 32 | * these can be patched with adb if the |
| 33 | * default values are inappropriate |
| 34 | */ |
| 35 | |
| 36 | int hd_t1 = T1; |
| 37 | int hd_t3 = T3; |
| 38 | int hd_n2 = N2; |
| 39 | |
| 40 | /* |
| 41 | * HDLC TIMER |
| 42 | * |
| 43 | * This routine is called every 500ms by the kernel. Decrement timer by this |
| 44 | * amount - if expired then process the event. |
| 45 | */ |
| 46 | |
| 47 | hd_timer () |
| 48 | { |
| 49 | register struct hdcb *hdp; |
| 50 | register int s = splimp (); |
| 51 | |
| 52 | for (hdp = hdcbhead; hdp; hdp = hdp->hd_next) { |
| 53 | if (hdp->hd_rrtimer && (--hdp->hd_rrtimer == 0)) { |
| 54 | if (hdp->hd_lasttxnr != hdp->hd_vr) |
| 55 | hd_writeinternal (hdp, RR, POLLOFF); |
| 56 | } |
| 57 | |
| 58 | if (!(hdp->hd_timer && --hdp->hd_timer == 0)) |
| 59 | continue; |
| 60 | |
| 61 | switch (hdp->hd_state) { |
| 62 | case INIT: |
| 63 | case DISC_SENT: |
| 64 | hd_writeinternal (hdp, DISC, POLLON); |
| 65 | break; |
| 66 | |
| 67 | case ABM: |
| 68 | if (hdp->hd_lastrxnr != hdp->hd_vs) { /* XXX */ |
| 69 | hdp->hd_timeouts++; |
| 70 | hd_resend_iframe (hdp); |
| 71 | } |
| 72 | break; |
| 73 | |
| 74 | case WAIT_SABM: |
| 75 | hd_writeinternal (hdp, FRMR, POLLOFF); |
| 76 | if (++hdp->hd_retxcnt == hd_n2) { |
| 77 | hdp->hd_retxcnt = 0; |
| 78 | hd_writeinternal (hdp, SABM, POLLOFF); |
| 79 | hdp->hd_state = WAIT_UA; |
| 80 | } |
| 81 | break; |
| 82 | |
| 83 | case DM_SENT: |
| 84 | if (++hdp->hd_retxcnt == hd_n2) { |
| 85 | /* Notify the packet level. */ |
| 86 | (void) pk_ctlinput (PRC_LINKDOWN, hdp->hd_pkp); |
| 87 | hdp->hd_retxcnt = 0; |
| 88 | hdp->hd_state = SABM_SENT; |
| 89 | hd_writeinternal (hdp, SABM, POLLOFF); |
| 90 | } else |
| 91 | hd_writeinternal (hdp, DM, POLLOFF); |
| 92 | break; |
| 93 | |
| 94 | case WAIT_UA: |
| 95 | if (++hdp->hd_retxcnt == hd_n2) { |
| 96 | hdp->hd_retxcnt = 0; |
| 97 | hd_writeinternal (hdp, DM, POLLOFF); |
| 98 | hdp->hd_state = DM_SENT; |
| 99 | } else |
| 100 | hd_writeinternal (hdp, SABM, POLLOFF); |
| 101 | break; |
| 102 | |
| 103 | case SABM_SENT: |
| 104 | /* Do this indefinitely. */ |
| 105 | hd_writeinternal (hdp, SABM, POLLON); |
| 106 | break; |
| 107 | |
| 108 | case DISCONNECTED: |
| 109 | /* |
| 110 | * Poll the interface driver flags waiting |
| 111 | * for the IFF_UP bit to come on. |
| 112 | */ |
| 113 | if (hdp->hd_ifp->if_flags & IFF_UP) |
| 114 | hdp->hd_state = INIT; |
| 115 | |
| 116 | } |
| 117 | SET_TIMER (hdp); |
| 118 | } |
| 119 | |
| 120 | splx (s); |
| 121 | } |