diff options
author | Denis Vlasenko <vda.linux@googlemail.com> | 2007-06-18 03:40:26 +0400 |
---|---|---|
committer | Denis Vlasenko <vda.linux@googlemail.com> | 2007-06-18 03:40:26 +0400 |
commit | bd7bb299c0e9ee5ff52c9d12b46fb14a907b34da (patch) | |
tree | 117a635e9457e1a932bc64941db5869e33179fc9 /networking/zcip.c | |
parent | 459be35234cc24b69309eb0ee22600024c73713e (diff) |
wget: use monotonic_sec instead of gettimeofday
zcip: use monotonic_us instead of gettimeofday
udhcpcd: simpler, shorter random_xid()
function old new delta
monotonic_sec - 41 +41
find_pair 164 180 +16
run_list_real 2018 2028 +10
cmp_main 547 555 +8
collect_ctx 112 119 +7
singlemount 4544 4549 +5
time_main 1124 1128 +4
static.start_sec - 4 +4
static.lastupdate_sec - 4 +4
sock - 4 +4
read_package_field 253 257 +4
pick 38 40 +2
get_next_line 145 147 +2
count_lines 59 61 +2
process_stdin 435 433 -2
xstrtoul_range_sfx 229 226 -3
static.initialized 4 1 -3
dhcprelay_main 1125 1122 -3
catcher 380 377 -3
arping_main 1969 1966 -3
s 8 4 -4
cfg 4 - -4
static.lastupdate 8 - -8
start 8 - -8
random_xid 95 33 -62
.rodata 129114 129050 -64
zcip_main 1731 1576 -155
progressmeter 1035 867 -168
------------------------------------------------------------------------------
(add/remove: 4/3 grow/shrink: 10/11 up/down: 113/-490) Total: -377 bytes
Diffstat (limited to 'networking/zcip.c')
-rw-r--r-- | networking/zcip.c | 115 |
1 files changed, 53 insertions, 62 deletions
diff --git a/networking/zcip.c b/networking/zcip.c index eb0a7ba41..de4ee0b1a 100644 --- a/networking/zcip.c +++ b/networking/zcip.c @@ -23,7 +23,6 @@ // - avoid silent script failures, especially under load... // - link status monitoring (restart on link-up; stop on link-down) -#include "libbb.h" #include <syslog.h> #include <poll.h> #include <sys/wait.h> @@ -31,10 +30,13 @@ #include <net/ethernet.h> #include <net/if.h> #include <net/if_arp.h> - #include <linux/if_packet.h> #include <linux/sockios.h> +#include "libbb.h" + +/* We don't need more than 32 bits of the counter */ +#define MONOTONIC_US() ((unsigned)monotonic_us()) struct arp_packet { struct ether_header hdr; @@ -78,15 +80,12 @@ static void pick(struct in_addr *ip) { unsigned tmp; - /* use cheaper math than lrand48() mod N */ do { - tmp = (lrand48() >> 16) & IN_CLASSB_HOST; + tmp = rand() & IN_CLASSB_HOST; } while (tmp > (IN_CLASSB_HOST - 0x0200)); ip->s_addr = htonl((LINKLOCAL_ADDR + 0x0100) + tmp); } -/* TODO: we need a flag to direct bb_[p]error_msg output to stderr. */ - /** * Broadcast an ARP packet. */ @@ -151,7 +150,7 @@ static int run(char *argv[3], const char *intf, struct in_addr *ip) */ static unsigned ALWAYS_INLINE ms_rdelay(unsigned secs) { - return lrand48() % (secs * 1000); + return rand() % (secs * 1000); } /** @@ -176,29 +175,31 @@ int zcip_main(int argc, char **argv) struct ifreq ifr; char *intf; char *script_av[3]; - suseconds_t timeout; // milliseconds + int timeout_ms; /* must be signed */ unsigned conflicts; unsigned nprobes; unsigned nclaims; int ready; int verbose; } L; -#define null_ip (L.null_ip ) -#define null_addr (L.null_addr) -#define saddr (L.saddr ) -#define ip (L.ip ) -#define ifr (L.ifr ) -#define intf (L.intf ) -#define script_av (L.script_av) -#define timeout (L.timeout ) -#define conflicts (L.conflicts) -#define nprobes (L.nprobes ) -#define nclaims (L.nclaims ) -#define ready (L.ready ) -#define verbose (L.verbose ) +#define null_ip (L.null_ip ) +#define null_addr (L.null_addr ) +#define saddr (L.saddr ) +#define ip (L.ip ) +#define ifr (L.ifr ) +#define intf (L.intf ) +#define script_av (L.script_av ) +#define timeout_ms (L.timeout_ms) +#define conflicts (L.conflicts ) +#define nprobes (L.nprobes ) +#define nclaims (L.nclaims ) +#define ready (L.ready ) +#define verbose (L.verbose ) memset(&L, 0, sizeof(L)); + srand(MONOTONIC_US()); + #define FOREGROUND (opts & 1) #define QUIT (opts & 2) // parse commandline: prog [options] ifname script @@ -282,7 +283,7 @@ int zcip_main(int argc, char **argv) // - defend it, within limits while (1) { struct pollfd fds[1]; - struct timeval tv1; + unsigned deadline_us; struct arp_packet p; int source_ip_conflict = 0; @@ -293,24 +294,18 @@ int zcip_main(int argc, char **argv) fds[0].revents = 0; // poll, being ready to adjust current timeout - if (!timeout) { - timeout = ms_rdelay(PROBE_WAIT); + if (!timeout_ms) { + timeout_ms = ms_rdelay(PROBE_WAIT); // FIXME setsockopt(fd, SO_ATTACH_FILTER, ...) to // make the kernel filter out all packets except // ones we'd care about. } - // set tv1 to the point in time when we timeout - gettimeofday(&tv1, NULL); - tv1.tv_usec += (timeout % 1000) * 1000; - while (tv1.tv_usec > 1000000) { - tv1.tv_usec -= 1000000; - tv1.tv_sec++; - } - tv1.tv_sec += timeout / 1000; + // set deadline_us to the point in time when we timeout + deadline_us = MONOTONIC_US() + timeout_ms * 1000; - VDBG("...wait %ld %s nprobes=%d, nclaims=%d\n", - timeout, intf, nprobes, nclaims); - switch (poll(fds, 1, timeout)) { + VDBG("...wait %d %s nprobes=%u, nclaims=%u\n", + timeout_ms, intf, nprobes, nclaims); + switch (poll(fds, 1, timeout_ms)) { // timeout case 0: @@ -321,25 +316,24 @@ int zcip_main(int argc, char **argv) // have been received, so we can progress through the states if (nprobes < PROBE_NUM) { nprobes++; - VDBG("probe/%d %s@%s\n", + VDBG("probe/%u %s@%s\n", nprobes, intf, inet_ntoa(ip)); arp(fd, &saddr, ARPOP_REQUEST, ð_addr, null_ip, &null_addr, ip); - timeout = PROBE_MIN * 1000; - timeout += ms_rdelay(PROBE_MAX - - PROBE_MIN); + timeout_ms = PROBE_MIN * 1000; + timeout_ms += ms_rdelay(PROBE_MAX - PROBE_MIN); } else { // Switch to announce state. state = ANNOUNCE; nclaims = 0; - VDBG("announce/%d %s@%s\n", + VDBG("announce/%u %s@%s\n", nclaims, intf, inet_ntoa(ip)); arp(fd, &saddr, ARPOP_REQUEST, ð_addr, ip, ð_addr, ip); - timeout = ANNOUNCE_INTERVAL * 1000; + timeout_ms = ANNOUNCE_INTERVAL * 1000; } break; case RATE_LIMIT_PROBE: @@ -347,24 +341,24 @@ int zcip_main(int argc, char **argv) // have been received, so we can move immediately to the announce state state = ANNOUNCE; nclaims = 0; - VDBG("announce/%d %s@%s\n", + VDBG("announce/%u %s@%s\n", nclaims, intf, inet_ntoa(ip)); arp(fd, &saddr, ARPOP_REQUEST, ð_addr, ip, ð_addr, ip); - timeout = ANNOUNCE_INTERVAL * 1000; + timeout_ms = ANNOUNCE_INTERVAL * 1000; break; case ANNOUNCE: // timeouts in the ANNOUNCE state mean no conflicting ARP packets // have been received, so we can progress through the states if (nclaims < ANNOUNCE_NUM) { nclaims++; - VDBG("announce/%d %s@%s\n", + VDBG("announce/%u %s@%s\n", nclaims, intf, inet_ntoa(ip)); arp(fd, &saddr, ARPOP_REQUEST, ð_addr, ip, ð_addr, ip); - timeout = ANNOUNCE_INTERVAL * 1000; + timeout_ms = ANNOUNCE_INTERVAL * 1000; } else { // Switch to monitor state. @@ -375,7 +369,7 @@ int zcip_main(int argc, char **argv) run(script_av, intf, &ip); ready = 1; conflicts = 0; - timeout = -1; // Never timeout in the monitor state. + timeout_ms = -1; // Never timeout in the monitor state. // NOTE: all other exit paths // should deconfig ... @@ -386,14 +380,14 @@ int zcip_main(int argc, char **argv) case DEFEND: // We won! No ARP replies, so just go back to monitor. state = MONITOR; - timeout = -1; + timeout_ms = -1; conflicts = 0; break; default: // Invalid, should never happen. Restart the whole protocol. state = PROBE; pick(&ip); - timeout = 0; + timeout_ms = 0; nprobes = 0; nclaims = 0; break; @@ -403,20 +397,17 @@ int zcip_main(int argc, char **argv) case 1: // We need to adjust the timeout in case we didn't receive // a conflicting packet. - if (timeout > 0) { - struct timeval tv2; - - gettimeofday(&tv2, NULL); - if (timercmp(&tv1, &tv2, <)) { + if (timeout_ms > 0) { + unsigned diff = deadline_us - MONOTONIC_US(); + if ((int)(diff) < 0) { // Current time is greater than the expected timeout time. // Should never happen. VDBG("missed an expected timeout\n"); - timeout = 0; + timeout_ms = 0; } else { VDBG("adjusting timeout\n"); - timersub(&tv1, &tv2, &tv1); - timeout = 1000 * tv1.tv_sec - + tv1.tv_usec / 1000; + timeout_ms = diff / 1000; + if (!timeout_ms) timeout_ms = 1; } } @@ -484,13 +475,13 @@ int zcip_main(int argc, char **argv) conflicts++; if (conflicts >= MAX_CONFLICTS) { VDBG("%s ratelimit\n", intf); - timeout = RATE_LIMIT_INTERVAL * 1000; + timeout_ms = RATE_LIMIT_INTERVAL * 1000; state = RATE_LIMIT_PROBE; } // restart the whole protocol pick(&ip); - timeout = 0; + timeout_ms = 0; nprobes = 0; nclaims = 0; } @@ -500,7 +491,7 @@ int zcip_main(int argc, char **argv) if (source_ip_conflict) { VDBG("monitor conflict -- defending\n"); state = DEFEND; - timeout = DEFEND_INTERVAL * 1000; + timeout_ms = DEFEND_INTERVAL * 1000; arp(fd, &saddr, ARPOP_REQUEST, ð_addr, ip, @@ -518,7 +509,7 @@ int zcip_main(int argc, char **argv) // restart the whole protocol pick(&ip); - timeout = 0; + timeout_ms = 0; nprobes = 0; nclaims = 0; } @@ -528,7 +519,7 @@ int zcip_main(int argc, char **argv) VDBG("invalid state -- starting over\n"); state = PROBE; pick(&ip); - timeout = 0; + timeout_ms = 0; nprobes = 0; nclaims = 0; break; |