[Qemu-devel] [PATCH 1/2] net: truncate output file when using dump backend

[Qemu-devel] [PATCH 1/2] net: truncate output file when using dump backend

[Hervé Poussineau]

Signed-off-by: Hervé Poussineau <hpoussin@reactos.org>
---
 net/dump.c |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)

diff --git a/net/dump.c b/net/dump.c
index 0d0cbb2..8132411 100644
--- a/net/dump.c
+++ b/net/dump.c
@@ -106,7 +106,7 @@ static int net_dump_init(VLANState *vlan, const char *device,
     DumpState *s;
     int fd;
 
-    fd = open(filename, O_CREAT | O_WRONLY | O_BINARY, 0644);
+    fd = open(filename, O_CREAT | O_TRUNC | O_WRONLY | O_BINARY, 0644);
     if (fd < 0) {
         error_report("-net dump: can't open %s", filename);
         return -1;
-- 
1.7.6.3

[Qemu-devel] [PATCH 2/2] net: store correct timestamp in dump file

[Hervé Poussineau]

Signed-off-by: Hervé Poussineau <hpoussin@reactos.org>
---
 net/dump.c |    7 ++++++-
 1 files changed, 6 insertions(+), 1 deletions(-)

diff --git a/net/dump.c b/net/dump.c
index 8132411..4b48d48 100644
--- a/net/dump.c
+++ b/net/dump.c
@@ -30,6 +30,7 @@
 
 typedef struct DumpState {
     VLANClientState nc;
+    int64_t start_ts;
     int fd;
     int pcap_caplen;
 } DumpState;
@@ -70,7 +71,7 @@ static ssize_t dump_receive(VLANClientState *nc, const uint8_t *buf, size_t size
     ts = muldiv64(qemu_get_clock_ns(vm_clock), 1000000, get_ticks_per_sec());
     caplen = size > s->pcap_caplen ? s->pcap_caplen : size;
 
-    hdr.ts.tv_sec = ts / 1000000;
+    hdr.ts.tv_sec = ts / 1000000 + s->start_ts;
     hdr.ts.tv_usec = ts % 1000000;
     hdr.caplen = caplen;
     hdr.len = size;
@@ -104,6 +105,7 @@ static int net_dump_init(VLANState *vlan, const char *device,
     struct pcap_file_hdr hdr;
     VLANClientState *nc;
     DumpState *s;
+    struct tm tm;
     int fd;
 
     fd = open(filename, O_CREAT | O_TRUNC | O_WRONLY | O_BINARY, 0644);
@@ -136,6 +138,9 @@ static int net_dump_init(VLANState *vlan, const char *device,
     s->fd = fd;
     s->pcap_caplen = len;
 
+    qemu_get_timedate(&tm, 0);
+    s->start_ts = mktime(&tm);
+
     return 0;
 }
 
-- 
1.7.6.3

Re: [Qemu-devel] [PATCH 2/2] net: store correct timestamp in dump file

[Mark Wu]

On 11/07/2011 05:52 AM, Hervé Poussineau wrote:
> Signed-off-by: Hervé Poussineau<hpoussin@reactos.org>
> ---
>   net/dump.c |    7 ++++++-
>   1 files changed, 6 insertions(+), 1 deletions(-)
>
> diff --git a/net/dump.c b/net/dump.c
> index 8132411..4b48d48 100644
> --- a/net/dump.c
> +++ b/net/dump.c
> @@ -30,6 +30,7 @@
>
>   typedef struct DumpState {
>       VLANClientState nc;
> +    int64_t start_ts;
>       int fd;
>       int pcap_caplen;
>   } DumpState;
> @@ -70,7 +71,7 @@ static ssize_t dump_receive(VLANClientState *nc, const uint8_t *buf, size_t size
>       ts = muldiv64(qemu_get_clock_ns(vm_clock), 1000000, get_ticks_per_sec());
I agree that using host time as timestamp is more reasonable than the 
virtual clock because in most cases rtc for guest is based on host time 
not  virtual clock.
I think we can simply use "host_clock" instead of "vm_clock" to achieve 
that. It will use the same time as host no matter what option is 
specified for guest's rtc. With your patch, the time stamp will keep the 
same as the choice of guest rtc, which is utc default.

  -    ts = muldiv64(qemu_get_clock_ns(vm_clock), 1000000, 
get_ticks_per_sec());
+    ts = muldiv64(qemu_get_clock_ns(host_clock), 1000000, 
get_ticks_per_sec());
      caplen = size > s->pcap_caplen ? s->pcap_caplen : size;

Re: [Qemu-devel] [PATCH 1/2] net: truncate output file when using dump backend

[Stefan Hajnoczi]

On Sun, Nov 06, 2011 at 10:52:04PM +0100, Hervé Poussineau wrote:
> 
> Signed-off-by: Hervé Poussineau <hpoussin@reactos.org>
> ---
>  net/dump.c |    2 +-
>  1 files changed, 1 insertions(+), 1 deletions(-)

Reviewed-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>