projects / unix-history / blame
| Commit | Line | Data |
|---|---|---|
| f03530e6 BJ |
1 | /* tcp_timer.c 4.1 81/11/24 */ |
| 2 | ||
| 3 | #include "../h/param.h" | |
| 4 | #include "../h/systm.h" | |
| 5 | #include "../h/mbuf.h" | |
| 6 | #include "../h/socket.h" | |
| 7 | #include "../h/socketvar.h" | |
| 8 | #include "../h/protosw.h" | |
| 9 | #include "../net/inet.h" | |
| 10 | #include "../net/inet_pcb.h" | |
| 11 | #include "../net/inet_systm.h" | |
| 12 | #include "../net/if.h" | |
| 13 | #include "../net/imp.h" | |
| 14 | #include "../net/ip.h" | |
| 15 | #include "../net/ip_var.h" | |
| 16 | #include "../net/tcp.h" | |
| 17 | #include "../net/tcp_fsm.h" | |
| 18 | #include "../net/tcp_var.h" | |
| 19 | #include "/usr/include/errno.h" | |
| 20 | ||
| 21 | /* | |
| 22 | * Fast timeout routine for processing delayed acks | |
| 23 | */ | |
| 24 | tcp_fasttimo() | |
| 25 | { | |
| 26 | ||
| 27 | } | |
| 28 | ||
| 29 | /* | |
| 30 | * Tcp protocol timeout routine called every 500 ms. | |
| 31 | * Updates the timers in all active tcb's and | |
| 32 | * causes finite state machine actions if timers expire. | |
| 33 | */ | |
| 34 | tcp_slowtimo() | |
| 35 | { | |
| 36 | register struct inpcb *ip; | |
| 37 | register struct tcpcb *tp; | |
| 38 | int s = splnet(); | |
| 39 | register short *tmp; | |
| 40 | register int i; | |
| 41 | COUNT(TCP_TIMEO); | |
| 42 | ||
| 43 | /* | |
| 44 | * Search through tcb's and update active timers. | |
| 45 | */ | |
| 46 | for (ip = tcb.inp_next; ip != &tcb; ip = ip->inp_next) { | |
| 47 | tp = intotcpcb(ip); | |
| 48 | tmp = &tp->t_init; | |
| 49 | for (i = 0; i < TNTIMERS; i++) { | |
| 50 | if (*tmp && --*tmp == 0) | |
| 51 | (void) tcp_usrreq(tp->t_inpcb->inp_socket, | |
| 52 | PRU_SLOWTIMO, (struct mbuf *)0, | |
| 53 | (caddr_t)i); | |
| 54 | tmp++; | |
| 55 | } | |
| 56 | tp->t_xmt++; | |
| 57 | } | |
| 58 | tcp_iss += ISSINCR/2; /* increment iss */ | |
| 59 | splx(s); | |
| 60 | } | |
| 61 | ||
| 62 | /* | |
| 63 | * Cancel all timers for tcp tp. | |
| 64 | */ | |
| 65 | tcp_tcancel(tp) | |
| 66 | struct tcpcb *tp; | |
| 67 | { | |
| 68 | register short *tmp = &tp->t_init; | |
| 69 | register int i; | |
| 70 | ||
| 71 | for (i = 0; i < TNTIMERS; i++) | |
| 72 | *tmp++ = 0; | |
| 73 | } | |
| 74 | ||
| 75 | /* | |
| 76 | * TCP timer went off processing. | |
| 77 | */ | |
| 78 | tcp_timers(tp, timertype) | |
| 79 | register struct tcpcb *tp; | |
| 80 | int timertype; | |
| 81 | { | |
| 82 | ||
| 83 | COUNT(TCP_TIMERS); | |
| 84 | switch (timertype) { | |
| 85 | ||
| 86 | case TFINACK: /* fin-ack timer */ | |
| 87 | switch (tp->t_state) { | |
| 88 | ||
| 89 | case TIME_WAIT: | |
| 90 | /* | |
| 91 | * We can be sure our ACK of foreign FIN was rcvd, | |
| 92 | * and can close if no data left for user. | |
| 93 | */ | |
| 94 | if (rcv_empty(tp)) { | |
| 95 | tcp_disconnect(tp); | |
| 96 | return (CLOSED); | |
| 97 | } | |
| 98 | return (RCV_WAIT); /* 17 */ | |
| 99 | ||
| 100 | case CLOSING: | |
| 101 | tp->tc_flags |= TC_WAITED_2_ML; | |
| 102 | return (SAME); | |
| 103 | ||
| 104 | default: | |
| 105 | return (SAME); | |
| 106 | } | |
| 107 | ||
| 108 | case TREXMT: /* retransmission timer */ | |
| 109 | if (tp->t_rexmt_val > tp->snd_una) { /* 34 */ | |
| 110 | /* | |
| 111 | * Set so for a retransmission, increase rexmt time | |
| 112 | * in case of multiple retransmissions. | |
| 113 | */ | |
| 114 | tp->snd_nxt = tp->snd_una; | |
| 115 | tp->tc_flags |= TC_REXMT; | |
| 116 | tp->t_xmtime = tp->t_xmtime << 1; | |
| 117 | if (tp->t_xmtime > T_REMAX) | |
| 118 | tp->t_xmtime = T_REMAX; | |
| 119 | (void) tcp_send(tp); | |
| 120 | } | |
| 121 | return (SAME); | |
| 122 | ||
| 123 | case TREXMTTL: /* retransmit too long */ | |
| 124 | if (tp->t_rtl_val > tp->snd_una) { /* 36 */ | |
| 125 | tcp_error(tp, ETIMEDOUT); | |
| 126 | return (CLOSED); | |
| 127 | } | |
| 128 | return (SAME); | |
| 129 | ||
| 130 | case TPERSIST: /* persist timer */ | |
| 131 | /* | |
| 132 | * Force a byte send through closed window. | |
| 133 | */ | |
| 134 | tp->tc_flags |= TC_FORCE_ONE; | |
| 135 | (void) tcp_send(tp); | |
| 136 | return (SAME); | |
| 137 | } | |
| 138 | panic("tcp_timers"); | |
| 139 | /*NOTREACHED*/ | |
| 140 | } |