From 724c7df683b8f3d0c487ce3d3cdcc1f6e762c181 Mon Sep 17 00:00:00 2001 From: Denys Vlasenko Date: Sat, 12 Dec 2020 21:44:32 +0100 Subject: traceroute: untangle main loop function old new delta common_traceroute_main 1785 1730 -55 Signed-off-by: Denys Vlasenko --- networking/traceroute.c | 218 +++++++++++++++++++++++------------------------- 1 file changed, 106 insertions(+), 112 deletions(-) (limited to 'networking') diff --git a/networking/traceroute.c b/networking/traceroute.c index 0fb01ff5b..1e96a73cf 100644 --- a/networking/traceroute.c +++ b/networking/traceroute.c @@ -463,6 +463,8 @@ wait_for_reply(unsigned *timestamp_us, int *left_ms) recv_pkt, sizeof(recv_pkt), /*flags:*/ MSG_DONTWAIT, &G.from_lsa->u.sa, G.to, G.from_lsa->len); + if (read_len < 0) + bb_perror_msg_and_die("recv"); t = monotonic_us(); *left_ms -= (t - *timestamp_us) / 1000; *timestamp_us = t; @@ -1076,147 +1078,139 @@ common_traceroute_main(int op, char **argv) for (ttl = G.first_ttl; ttl <= G.max_ttl; ++ttl) { int probe; int unreachable = 0; /* counter */ - int gotlastaddr = 0; /* flags */ int got_there = 0; printf("%2d", ttl); for (probe = 0; probe < G.nprobes; ++probe) { - int read_len; unsigned t1; unsigned t2; int left_ms; + int read_len; + int icmp_code; fflush_all(); if (probe != 0) msleep(G.pausemsecs); send_probe(++seq, ttl); - t2 = t1 = monotonic_us(); + t2 = t1 = monotonic_us(); left_ms = waittime * 1000; - /* NB: wait_for_reply() fills "G.from_lsa" and "G.to" with - * "where it came from" and "what local address it arrived to" - * addresses. - */ - while ((read_len = wait_for_reply(&t2, &left_ms)) != 0) { - int icmp_code; - - /* Recv'ed a packet, or read error */ - /* t2 = monotonic_us() - set by wait_for_reply */ - - if (read_len < 0) - continue; - icmp_code = packet_ok(read_len, seq); - /* Skip short packet */ - if (icmp_code == 0) - continue; - - if (!gotlastaddr - || (memcmp(lastaddr, &G.from_lsa->u.sa, G.from_lsa->len) != 0) - ) { - print(read_len); - memcpy(lastaddr, &G.from_lsa->u.sa, G.from_lsa->len); - gotlastaddr = 1; + for (;;) { + /* NB: wait_for_reply() fills "G.from_lsa" and "G.to" with + * "where it came from" and "what local address it arrived to" + * addresses. Sets t2 = monotonic_us(), updates left_ms. + */ + read_len = wait_for_reply(&t2, &left_ms); + + if (read_len == 0) { /* there was no packet at all? */ + printf(" *"); + goto next_probe; } + icmp_code = packet_ok(read_len, seq); + if (icmp_code != 0) + break; /* got a good response */ + /* unrecognized type/code or too short, back to recv */ + } - print_delta_ms(t1, t2); - - if (G.from_lsa->u.sa.sa_family == AF_INET) { - if (op & OPT_TTL_FLAG) { - struct ip *ip = (struct ip *)recv_pkt; - printf(" (%d)", ip->ip_ttl); - } + if (probe == 0 + || (memcmp(lastaddr, &G.from_lsa->u.sa, G.from_lsa->len) != 0) + ) { + print(read_len); + memcpy(lastaddr, &G.from_lsa->u.sa, G.from_lsa->len); + } + print_delta_ms(t1, t2); + if (G.from_lsa->u.sa.sa_family == AF_INET) { + if (op & OPT_TTL_FLAG) { + struct ip *ip = (struct ip *)recv_pkt; + printf(" (%d)", ip->ip_ttl); } + } - /* Got a "time exceeded in transit" icmp message? */ - if (icmp_code == -1) - break; + /* Got a "time exceeded in transit" icmp message? */ + if (icmp_code == -1) + continue; - icmp_code--; - switch (icmp_code) { + icmp_code--; + switch (icmp_code) { #if ENABLE_TRACEROUTE6 - case ICMP6_DST_UNREACH_NOPORT << 8: - got_there = 1; - break; + case ICMP6_DST_UNREACH_NOPORT << 8: + got_there = 1; + break; #endif - case ICMP_UNREACH_PORT: { - struct ip *ip = (struct ip *)recv_pkt; - if (ip->ip_ttl <= 1) - printf(" !"); - got_there = 1; - break; - } - case ICMP_UNREACH_NET: + case ICMP_UNREACH_PORT: { + struct ip *ip = (struct ip *)recv_pkt; + if (ip->ip_ttl <= 1) + printf(" !"); + got_there = 1; + break; + } + case ICMP_UNREACH_NET: #if ENABLE_TRACEROUTE6 && (ICMP6_DST_UNREACH_NOROUTE != ICMP_UNREACH_NET) - case ICMP6_DST_UNREACH_NOROUTE << 8: + case ICMP6_DST_UNREACH_NOROUTE << 8: #endif - printf(" !N"); - ++unreachable; - break; - case ICMP_UNREACH_HOST: + printf(" !N"); + ++unreachable; + break; + case ICMP_UNREACH_HOST: #if ENABLE_TRACEROUTE6 - case ICMP6_DST_UNREACH_ADDR << 8: + case ICMP6_DST_UNREACH_ADDR << 8: #endif - printf(" !H"); - ++unreachable; - break; - case ICMP_UNREACH_PROTOCOL: - printf(" !P"); - got_there = 1; - break; - case ICMP_UNREACH_NEEDFRAG: - printf(" !F-%d", pmtu); - ++unreachable; - break; - case ICMP_UNREACH_SRCFAIL: + printf(" !H"); + ++unreachable; + break; + case ICMP_UNREACH_PROTOCOL: + printf(" !P"); + got_there = 1; + break; + case ICMP_UNREACH_NEEDFRAG: + printf(" !F-%d", pmtu); + ++unreachable; + break; + case ICMP_UNREACH_SRCFAIL: #if ENABLE_TRACEROUTE6 - case ICMP6_DST_UNREACH_ADMIN << 8: + case ICMP6_DST_UNREACH_ADMIN << 8: #endif - printf(" !S"); - ++unreachable; - break; - case ICMP_UNREACH_FILTER_PROHIB: - case ICMP_UNREACH_NET_PROHIB: /* misuse */ - printf(" !A"); - ++unreachable; - break; - case ICMP_UNREACH_HOST_PROHIB: - printf(" !C"); - ++unreachable; - break; - case ICMP_UNREACH_HOST_PRECEDENCE: - printf(" !V"); - ++unreachable; - break; - case ICMP_UNREACH_PRECEDENCE_CUTOFF: - printf(" !C"); - ++unreachable; - break; - case ICMP_UNREACH_NET_UNKNOWN: - case ICMP_UNREACH_HOST_UNKNOWN: - printf(" !U"); - ++unreachable; - break; - case ICMP_UNREACH_ISOLATED: - printf(" !I"); - ++unreachable; - break; - case ICMP_UNREACH_TOSNET: - case ICMP_UNREACH_TOSHOST: - printf(" !T"); - ++unreachable; - break; - default: - printf(" !<%d>", icmp_code); - ++unreachable; - break; - } + printf(" !S"); + ++unreachable; break; - } /* while (wait and read a packet) */ - - /* there was no packet at all? */ - if (read_len == 0) - printf(" *"); + case ICMP_UNREACH_FILTER_PROHIB: + case ICMP_UNREACH_NET_PROHIB: /* misuse */ + printf(" !A"); + ++unreachable; + break; + case ICMP_UNREACH_HOST_PROHIB: + printf(" !C"); + ++unreachable; + break; + case ICMP_UNREACH_HOST_PRECEDENCE: + printf(" !V"); + ++unreachable; + break; + case ICMP_UNREACH_PRECEDENCE_CUTOFF: + printf(" !C"); + ++unreachable; + break; + case ICMP_UNREACH_NET_UNKNOWN: + case ICMP_UNREACH_HOST_UNKNOWN: + printf(" !U"); + ++unreachable; + break; + case ICMP_UNREACH_ISOLATED: + printf(" !I"); + ++unreachable; + break; + case ICMP_UNREACH_TOSNET: + case ICMP_UNREACH_TOSHOST: + printf(" !T"); + ++unreachable; + break; + default: + printf(" !<%d>", icmp_code); + ++unreachable; + break; + } + next_probe: ; } /* for (nprobes) */ bb_putchar('\n'); -- cgit v1.2.3