net/dump: simplify timestamp calculation

The timestamp calculation in dump_receive is very unobvious now and
looks completely arbitrary. qemu_clock_get_us already returns micro-
seconds, so use that instead of manual calculating with nanoseconds.

While at it, express the private start_ts field in microseconds too
instead of seconds. This is supposed to yield a more accurate initial
timestamp (based on host clock). NOTE: this patch ignores the RTC of
the guest! Perhaps this part should be reverted.

1 files changed, 3 insertions, 5 deletions

diff --git a/net/dump.c b/net/dump.c
index 9d3a09e334..d956dc1c19 100644
--- a/net/dump.c
+++ b/net/dump.c
@@ -69,10 +69,10 @@ static ssize_t dump_receive(NetClientState *nc, const uint8_t *buf, size_t size)
         return size;
     }
 
-    ts = muldiv64(qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL), 1000000, get_ticks_per_sec());
+    ts = s->start_ts + qemu_clock_get_us(QEMU_CLOCK_VIRTUAL);
     caplen = size > s->pcap_caplen ? s->pcap_caplen : size;
 
-    hdr.ts.tv_sec = ts / 1000000 + s->start_ts;
+    hdr.ts.tv_sec = ts / 1000000;
     hdr.ts.tv_usec = ts % 1000000;
     hdr.caplen = caplen;
     hdr.len = size;
@@ -106,7 +106,6 @@ static int net_dump_init(NetClientState *peer, const char *device,
     struct pcap_file_hdr hdr;
     NetClientState *nc;
     DumpState *s;
-    struct tm tm;
     int fd;
 
     fd = open(filename, O_CREAT | O_TRUNC | O_WRONLY | O_BINARY, 0644);
@@ -139,8 +138,7 @@ static int net_dump_init(NetClientState *peer, const char *device,
     s->fd = fd;
     s->pcap_caplen = len;
 
-    qemu_get_timedate(&tm, 0);
-    s->start_ts = mktime(&tm);
+    s->start_ts = qemu_clock_get_us(QEMU_CLOCK_HOST);
 
     return 0;
 }