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Wireshark-dev: [Wireshark-dev] [Patch] iSeries wiretap packet precision

From: Martin Warnes <martin@xxxxxxxxxxxxxxxxx>
Date: Wed, 04 Oct 2006 08:16:44 +0100
Hi/

I submitted the attached patch a while back but it seems to have slipped through the cracks.

The patch addresses issues with higher precision packet
timings on top end iSeries hardware and should enable the iseries
wiretap to handle timings in both micro and nano seconds.

Regards .. Martin


Index: iseries.c
===================================================================
--- iseries.c	(revision 19389)
+++ iseries.c	(working copy)
@@ -159,9 +159,9 @@
   /* UNICODE identification */
   char unicodemagic[ISERIES_HDR_MAGIC_LEN] =
     { '\xFF', '\xFE', '\x20', '\x00', '\x43', '\x00', '\x4F', '\x00', '\x4D',
-      '\x00', '\x4D', '\x00', '\x55', '\x00', '\x4E', '\x00', '\x49', '\x00',
-      '\x43', '\x00', '\x41'
-    };
+    '\x00', '\x4D', '\x00', '\x55', '\x00', '\x4E', '\x00', '\x49', '\x00',
+    '\x43', '\x00', '\x41'
+  };
 
   /*
    * Check that file starts with a valid iSeries COMMS TRACE header
@@ -536,8 +536,8 @@
    * If we have Wiretap Header then populate it here
    *
    * XXX - Timer resolution on the iSeries is hardware dependant, the value for csec may be
-   * different on other platforms though all the traces I've seen seem so show resolution
-   * to 5 digits (i.e HH:MM:SS.nnnnn) so hopefully this will not require special handling
+   * different on other platforms though all the traces I've seen seem to show resolution
+   * to Milliseconds (i.e HH:MM:SS.nnnnn) or Nanoseconds (i.e HH:MM:SS.nnnnnn)
    */
   if (wth->capture.iseries->sdate)
     {
@@ -551,7 +551,16 @@
       tm.tm_sec = sec;
       tm.tm_isdst = -1;
       wth->phdr.ts.secs = mktime (&tm);
-      wth->phdr.ts.nsecs = csec * 10000;
+      /* Handle Millisecond precision for timer */
+      if (csec > 99999)
+	{
+	  wth->phdr.ts.nsecs = csec * 1000;
+	}
+      /* Handle Nanosecond precision for timer */
+      else
+	{
+	  wth->phdr.ts.nsecs = csec * 10000;
+	}
       wth->phdr.caplen = cap_len;
       wth->phdr.pkt_encap = WTAP_ENCAP_ETHERNET;
       pseudo_header->eth.fcs_len = -1;
@@ -594,7 +603,7 @@
 	    }
 	}
 
-      /* Convert UNICODE data to ASCII and determine line length*/
+      /* Convert UNICODE data to ASCII and determine line length */
       if (wth->capture.iseries->format == ISERIES_FORMAT_UNICODE)
 	{
 	  buflen = iseries_UNICODE_to_ASCII (data, ISERIES_LINE_LENGTH);