From 70726640b33e50d0802f297c5a3f18494a488c8d Mon Sep 17 00:00:00 2001 From: Denys Vlasenko Date: Sat, 12 Dec 2020 17:45:49 +0100 Subject: traceroute: code shrink Do not pass "from" and "to" addresses as parameters, keep them in globals function old new delta common_traceroute_main 3426 3391 -35 Signed-off-by: Denys Vlasenko --- networking/traceroute.c | 84 +++++++++++++++++++++---------------------------- 1 file changed, 35 insertions(+), 49 deletions(-) diff --git a/networking/traceroute.c b/networking/traceroute.c index 764d66ef8..588570fcb 100644 --- a/networking/traceroute.c +++ b/networking/traceroute.c @@ -389,6 +389,8 @@ struct globals { struct outdata_t *outdata; len_and_sockaddr *dest_lsa; + len_and_sockaddr *from_lsa; /* response came from this address */ + struct sockaddr *to; /* response came to this (local) address */ int packlen; /* total length of packet */ int pmtu; /* Path MTU Discovery (RFC1191) */ uint32_t ident; @@ -442,7 +444,7 @@ struct globals { */ static int -wait_for_reply(len_and_sockaddr *from_lsa, struct sockaddr *to, unsigned *timestamp_us, int *left_ms) +wait_for_reply(unsigned *timestamp_us, int *left_ms) { struct pollfd pfd[1]; int read_len = 0; @@ -455,7 +457,7 @@ wait_for_reply(len_and_sockaddr *from_lsa, struct sockaddr *to, unsigned *timest read_len = recv_from_to(rcvsock, recv_pkt, sizeof(recv_pkt), /*flags:*/ MSG_DONTWAIT, - &from_lsa->u.sa, to, from_lsa->len); + &G.from_lsa->u.sa, G.to, G.from_lsa->len); t = monotonic_us(); *left_ms -= (t - *timestamp_us) / 1000; *timestamp_us = t; @@ -598,7 +600,7 @@ pr_type(unsigned char t) packet4_ok(read_len, seq) #endif static int -packet4_ok(int read_len, const struct sockaddr_in *from, int seq) +packet4_ok(int read_len, int seq) { const struct icmp *icp; unsigned char type, code; @@ -616,7 +618,7 @@ packet4_ok(int read_len, const struct sockaddr_in *from, int seq) #if ENABLE_FEATURE_TRACEROUTE_VERBOSE if (verbose) printf("packet too short (%d bytes) from %s\n", read_len, - inet_ntoa(from->sin_addr)); + inet_ntoa(G.from_lsa->u.sin.sin_addr)); #endif return 0; } @@ -680,7 +682,7 @@ packet4_ok(int read_len, const struct sockaddr_in *from, int seq) uint32_t *lp = (uint32_t *)&icp->icmp_ip; printf("\n%d bytes from %s", - read_len, inet_ntoa(from->sin_addr)); + read_len, inet_ntoa(G.from_lsa->u.sin.sin_addr)); /* Two separate printf() because inet_ntoa() returns static string */ printf(" to %s: icmp type %d (%s) code %d\n", inet_ntoa(ip->ip_dst), @@ -694,14 +696,8 @@ packet4_ok(int read_len, const struct sockaddr_in *from, int seq) #if ENABLE_TRACEROUTE6 -# if !ENABLE_FEATURE_TRACEROUTE_VERBOSE -#define packet6_ok(read_len, from_lsa, to, seq) \ - packet6_ok(read_len, from_lsa, seq) -# endif static int -packet6_ok(int read_len, const struct sockaddr_in6 *from, - struct sockaddr *to, - int seq) +packet6_ok(int read_len, int seq) { const struct icmp6_hdr *icp; unsigned char type, code; @@ -757,21 +753,18 @@ packet6_ok(int read_len, const struct sockaddr_in6 *from, # if ENABLE_FEATURE_TRACEROUTE_VERBOSE if (verbose) { -# ifndef MAXHOSTNAMELEN -# define MAXHOSTNAMELEN 80 -# endif unsigned char *p; - char pa[MAXHOSTNAMELEN]; + char pa[sizeof("ffff:ffff:ffff:ffff:ffff:ffff:ffff:ffff") + 4]; int i; p = (unsigned char *) (icp + 1); printf("\n%d bytes from %s", read_len, - inet_ntop(AF_INET6, &from->sin6_addr, pa, sizeof(pa))); + inet_ntop(AF_INET6, &G.from_lsa->u.sin6.sin6_addr, pa, sizeof(pa))); /* Two printf() instead of one - reuse string constants */ printf(" to %s: icmp type %d (%s) code %d\n", - inet_ntop(AF_INET6, &((struct sockaddr_in6*)to)->sin6_addr, pa, sizeof(pa)), + inet_ntop(AF_INET6, &((struct sockaddr_in6*)G.to)->sin6_addr, pa, sizeof(pa)), type, pr_type(type), icp->icmp6_code); read_len -= sizeof(struct icmp6_hdr); @@ -790,29 +783,21 @@ packet6_ok(int read_len, const struct sockaddr_in6 *from, return 0; } -# if !ENABLE_FEATURE_TRACEROUTE_VERBOSE -#define packet_ok(read_len, from_lsa, to, seq) \ - packet_ok(read_len, from_lsa, seq) -# endif + static int -packet_ok(int read_len, len_and_sockaddr *from_lsa, - struct sockaddr *to, - int seq) +packet_ok(int read_len, int seq) { - if (from_lsa->u.sa.sa_family == AF_INET) - return packet4_ok(read_len, &from_lsa->u.sin, seq); - return packet6_ok(read_len, &from_lsa->u.sin6, to, seq); + if (G.from_lsa->u.sa.sa_family == AF_INET) + return packet4_ok(read_len, seq); + return packet6_ok(read_len, seq); } #else /* !ENABLE_TRACEROUTE6 */ static ALWAYS_INLINE int -packet_ok(int read_len, - len_and_sockaddr *from_lsa IF_NOT_FEATURE_TRACEROUTE_VERBOSE(UNUSED_PARAM), - struct sockaddr *to UNUSED_PARAM, - int seq) +packet_ok(int read_len, int seq) { - return packet4_ok(read_len, &from_lsa->u.sin, seq); + return packet4_ok(read_len, seq); } #endif @@ -845,19 +830,19 @@ print_inetname(const struct sockaddr *from) } static void -print(int read_len, const struct sockaddr *from, const struct sockaddr *to) +print(int read_len) { - print_inetname(from); + print_inetname(&G.from_lsa->u.sa); if (verbose) { - char *ina = xmalloc_sockaddr2dotted_noport(to); + char *ina = xmalloc_sockaddr2dotted_noport(G.to); #if ENABLE_TRACEROUTE6 /* NB: reads from (AF_INET, SOCK_RAW, IPPROTO_ICMP) socket * return the entire IP packet (IOW: they do not strip IP header). * Reads from (AF_INET6, SOCK_RAW, IPPROTO_ICMPV6) do strip IPv6 * header and return only ICMP6 packet. Weird. */ - if (to->sa_family == AF_INET6) { + if (G.to->sa_family == AF_INET6) { /* read_len -= sizeof(struct ip6_hdr); - WRONG! */ } else #endif @@ -910,9 +895,7 @@ common_traceroute_main(int op, char **argv) #endif int ttl; int seq; - len_and_sockaddr *from_lsa; struct sockaddr *lastaddr; - struct sockaddr *to; /* Ensure the socket fds won't be 0, 1 or 2 */ bb_sanitize_stdio(); @@ -1121,9 +1104,9 @@ common_traceroute_main(int op, char **argv) printf(" from %s", source); printf(", %d hops max, %d byte packets\n", max_ttl, packlen); - from_lsa = xmemdup(dest_lsa, LSA_LEN_SIZE + dest_lsa->len); lastaddr = xzalloc(dest_lsa->len); - to = xzalloc(dest_lsa->len); + G.from_lsa = xmemdup(dest_lsa, LSA_LEN_SIZE + dest_lsa->len); + G.to = xzalloc(dest_lsa->len); seq = 0; for (ttl = first_ttl; ttl <= max_ttl; ++ttl) { int probe; @@ -1146,7 +1129,10 @@ common_traceroute_main(int op, char **argv) t2 = t1 = monotonic_us(); left_ms = waittime * 1000; - while ((read_len = wait_for_reply(from_lsa, to, &t2, &left_ms)) != 0) { + /* NB: wait_for_reply() fills "G.from_lsa" and "G.to" + * with "where it came from" and "to which local address it arrived". + */ + while ((read_len = wait_for_reply(&t2, &left_ms)) != 0) { int icmp_code; /* Recv'ed a packet, or read error */ @@ -1154,22 +1140,22 @@ common_traceroute_main(int op, char **argv) if (read_len < 0) continue; - icmp_code = packet_ok(read_len, from_lsa, to, seq); + icmp_code = packet_ok(read_len, seq); /* Skip short packet */ if (icmp_code == 0) continue; if (!gotlastaddr - || (memcmp(lastaddr, &from_lsa->u.sa, from_lsa->len) != 0) + || (memcmp(lastaddr, &G.from_lsa->u.sa, G.from_lsa->len) != 0) ) { - print(read_len, &from_lsa->u.sa, to); - memcpy(lastaddr, &from_lsa->u.sa, from_lsa->len); + print(read_len); + memcpy(lastaddr, &G.from_lsa->u.sa, G.from_lsa->len); gotlastaddr = 1; } print_delta_ms(t1, t2); - if (from_lsa->u.sa.sa_family == AF_INET) { + 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); @@ -1276,9 +1262,9 @@ common_traceroute_main(int op, char **argv) } if (ENABLE_FEATURE_CLEAN_UP) { - free(to); + free(G.to); free(lastaddr); - free(from_lsa); + free(G.from_lsa); } return 0; -- cgit v1.2.3