From 0f322fb2d838920ac15a655d76ded4849606306f Mon Sep 17 00:00:00 2001
From: Srivats P <pstavirs@users.noreply.github.com>
Date: Sat, 15 Jan 2022 15:26:05 +0530
Subject: [PATCH] Read nanosec PCAP files natively in non-pdml mode
In PDML mode, nanosecond support is already present - in fact, only
nanosecond is supported not microseconds.
Updates #238
---
common/pcapfileformat.cpp | 27 +++++++++++++++++++--------
1 file changed, 19 insertions(+), 8 deletions(-)
diff --git a/common/pcapfileformat.cpp b/common/pcapfileformat.cpp
index 5de5080..7c6094c 100644
--- a/common/pcapfileformat.cpp
+++ b/common/pcapfileformat.cpp
@@ -33,6 +33,8 @@ along with this program. If not, see <http://www.gnu.org/licenses/>
const quint32 kPcapFileMagic = 0xa1b2c3d4;
const quint32 kPcapFileMagicSwapped = 0xd4c3b2a1;
+const quint32 kNanoSecondPcapFileMagic = 0xa1b23c4d;
+const quint32 kNanoSecondPcapFileMagicSwapped = 0x4d3cb2a1;
const quint16 kPcapFileVersionMajor = 2;
const quint16 kPcapFileVersionMinor = 4;
const quint32 kMaxSnapLen = 65535;
@@ -92,11 +94,12 @@ bool PcapFileFormat::open(const QString fileName,
QTemporaryFile file2;
quint32 magic;
uchar gzipMagic[2];
+ bool nsecResolution = false;
int len;
PcapFileHeader fileHdr;
PcapPacketHeader pktHdr;
OstProto::Stream *prevStream = NULL;
- uint lastUsec = 0;
+ quint64 lastXsec = 0;
int pktCount;
qint64 byteCount = 0;
qint64 byteTotal;
@@ -166,15 +169,22 @@ _retry:
{
// Do nothing
}
- else if (magic == kPcapFileMagicSwapped)
+ else if (magic == kNanoSecondPcapFileMagic)
+ {
+ nsecResolution = true;
+ }
+ else if ((magic == kPcapFileMagicSwapped)
+ || (magic == kNanoSecondPcapFileMagicSwapped))
{
// Toggle Byte order
if (fd_.byteOrder() == QDataStream::BigEndian)
fd_.setByteOrder(QDataStream::LittleEndian);
else
fd_.setByteOrder(QDataStream::BigEndian);
+
+ nsecResolution = (magic == kNanoSecondPcapFileMagicSwapped);
}
- else // Not a pcap file
+ else // Not a pcap file (could be pcapng or something else)
{
if (tryConvert)
{
@@ -460,6 +470,7 @@ _retry:
}
_non_pdml:
+ qDebug("pcap resolution: %s", nsecResolution ? "nsec" : "usec");
emit status("Reading Packets...");
emit target(100); // in percentage
pktCount = 1;
@@ -487,17 +498,17 @@ _non_pdml:
stream->mutable_control()->set_num_packets(1);
// setup packet rate to the timing in pcap (as close as possible)
- const double kUsecsInSec = 1e6;
- uint usec = (pktHdr.tsSec*kUsecsInSec + pktHdr.tsUsec);
- uint delta = usec - lastUsec;
+ const double kXsecsInSec = nsecResolution ? 1e9 : 1e6;
+ quint64 xsec = (pktHdr.tsSec*kXsecsInSec + pktHdr.tsUsec);
+ quint64 delta = xsec - lastXsec;
if ((pktCount != 1) && delta)
- stream->mutable_control()->set_packets_per_sec(kUsecsInSec/delta);
+ stream->mutable_control()->set_packets_per_sec(kXsecsInSec/delta);
if (prevStream)
prevStream->mutable_control()->CopyFrom(stream->control());
- lastUsec = usec;
+ lastXsec = xsec;
prevStream = stream;
pktCount++;
qDebug("pktCount = %d", pktCount);