diff options
Diffstat (limited to 'networking/pscan.c')
| -rw-r--r-- | networking/pscan.c | 28 |
1 files changed, 9 insertions, 19 deletions
diff --git a/networking/pscan.c b/networking/pscan.c index 10bf3b6..9fa6993 100644 --- a/networking/pscan.c +++ b/networking/pscan.c @@ -17,19 +17,6 @@ #define DERR(...) ((void)0) #endif -/* return time in usec */ -// TODO: move to libbb and use in traceroute, zcip, arping etc -// (maybe also use absolute monotonic clock - no time warps -// due to admin resetting date/time?) -static unsigned gettimeofday_us(void) -{ - struct timeval now; - - if (gettimeofday(&now, NULL)) - return 0; - return (now.tv_sec * 1000000 + now.tv_usec); -} - static const char *port_name(unsigned port) { struct servent *server; @@ -40,6 +27,9 @@ static const char *port_name(unsigned port) return "unknown"; } +/* We don't expect to see 1000+ seconds delay, unsigned is enough */ +#define MONOTONIC_US() ((unsigned)monotonic_us()) + int pscan_main(int argc, char **argv); int pscan_main(int argc, char **argv) { @@ -91,7 +81,7 @@ int pscan_main(int argc, char **argv) /* Nonblocking connect typically "fails" with errno == EINPROGRESS */ ndelay_on(s); DMSG("connect to port %u", port); - start = gettimeofday_us(); + start = MONOTONIC_US(); if (connect(s, &lsap->sa, lsap->len) == 0) { /* Unlikely, for me even localhost fails :) */ DMSG("connect succeeded"); @@ -110,15 +100,15 @@ int pscan_main(int argc, char **argv) closed_ports++; break; } - DERR("port %u errno %d @%u", port, errno, gettimeofday_us() - start); - if ((gettimeofday_us() - start) > rtt_4) + DERR("port %u errno %d @%u", port, errno, MONOTONIC_US() - start); + if ((MONOTONIC_US() - start) > rtt_4) break; /* Can sleep (much) longer than specified delay. * We check rtt BEFORE we usleep, otherwise * on localhost we'll do zero writes done (!) * before we exceed (rather small) rtt */ usleep(rtt_4/8); - DMSG("write to port %u @%u", port, gettimeofday_us() - start); + DMSG("write to port %u @%u", port, MONOTONIC_US() - start); if (write(s, " ", 1) >= 0) { /* We were able to write to the socket */ open: open_ports++; @@ -126,13 +116,13 @@ int pscan_main(int argc, char **argv) break; } } - DMSG("out of loop @%u", gettimeofday_us() - start); + DMSG("out of loop @%u", MONOTONIC_US() - start); /* Estimate new rtt - we don't want to wait entire timeout * for each port. *4 allows for rise in net delay. * We increase rtt quickly (*4), decrease slowly (4/8 == 1/2) * because we don't want to accidentally miss ports. */ - rtt_4 = (gettimeofday_us() - start) * 4; + rtt_4 = (MONOTONIC_US() - start) * 4; if (rtt_4 < min_rtt) rtt_4 = min_rtt; if (rtt_4 > timeout) |