Changeset 7bb7dda

Timestamp:

04/11/05 12:52:37 (16 years ago)

Author:

Daniel Lawson <dlawson@…>

Branches:

4.0.1-hotfixes, cachetimestamps, develop, dpdk-ndag, etsilive, getfragoff, help, libtrace4, master, ndag_format, pfring, rc-4.0.1, rc-4.0.2, rc-4.0.3, rc-4.0.4, ringdecrementfix, ringperformance, ringtimestampfixes

Children:

808a478

Parents:

be02abd

Message:

improved trace_event() in the case of trace playback. Seems to work fine now :)

Location:

lib

Files:

• libtrace.h (modified) (1 diff)
• trace.c (modified) (7 diffs)

lib/libtrace.h

@@ -460 +460 @@
  *  TRACE_EVENT_SLEEP   Next event in <seconds>
  *  TRACE_EVENT_PACKET  Packet arrived in <buffer> with size <size>
+ *  TRACE_EVENT_TERMINATE Trace terminated (perhaps with an error condition)
  */
 struct libtrace_eventobj_t trace_event(struct libtrace_t *trace,

lib/trace.c

@@ -167 +167 @@
                 int size;
         } packet;
+        double tdelta;
+        double trace_start_ts;
+        double real_start_ts;
+        double trace_last_ts;
+
         double last_ts;
         double start_ts;
-        struct timeval start_tv;
 };
 
@@ -202 +206 @@
         }
         strncpy(scan,uri, (uridata - uri));
+
+        (*libtrace)->tdelta = 0.0;
 
         if (!strncasecmp(scan,"erf",3)) {
@@ -1448 +1454 @@
  *  TRACE_EVENT_SLEEP   Next event in seconds
  *  TRACE_EVENT_PACKET  Packet arrived in buffer with size size
+ *  TRACE_EVENT_TERMINATE Trace terminated (perhaps with an error condition)
  * FIXME currently keeps a copy of the packet inside the trace pointer,
  * which in turn is stored inside the new packet object...
@@ -1478 +1485 @@
                                 if (data>0) {
                                         event.size = trace_read_packet(trace,packet);
-                                        if (event.size < 0) {
-                                                event.type = TRACE_EVENT_TERMINATE;
-                                                return event;
-                                        }
                                         event.type = TRACE_EVENT_PACKET;
                                         return event;
@@ -1500 +1503 @@
                                 if (data>0) {
                                         event.size = trace_read_packet(trace,packet);
-                                        if (event.size < 0) {
-                                                event.type = TRACE_EVENT_TERMINATE;
-                                                return event;
-                                        }
                                         event.type = TRACE_EVENT_PACKET;
                                         return event;
@@ -1521 +1520 @@
                                         trace->packet.size=
                                                 trace_read_packet(trace,packet);
+                                        event.size = trace->packet.size;
                                         if (trace->packet.size > 0 ) {
                                                 memcpy(trace->packet.buffer,packet->buffer,trace->packet.size);
+                                        } else {
+                                                // return here, the test for event.size will sort out the error
+                                                event.type = TRACE_EVENT_PACKET;
+                                                return event;
                                         }
                                 }
-                                event.size = trace->packet.size;
-
-                                if (event.size == 0) {
-                                        event.type = TRACE_EVENT_TERMINATE;
-                                        return event;
-                                }
 
                                 ts=trace_get_seconds(packet);
-                                if (trace->last_ts!=0) {
-                                        event.seconds = ts - trace->last_ts;
+                                if (trace->tdelta!=0) {
+                                        // Get the adjusted current time
                                         gettimeofday(&stv, NULL);
                                         now = stv.tv_sec + ((double)stv.tv_usec / 1000000.0);
+                                        now -= trace->tdelta; // adjust for trace delta
                                         
-                                        if (event.seconds > (now - trace->start_ts)) {
+                                        
+                                        // if the trace timestamp is still in the future, 
+                                        // return a SLEEP event, otherwise fire the packet
+                                        if (ts > now) {
+                                                event.seconds = ts - trace->trace_last_ts;
                                                 event.type = TRACE_EVENT_SLEEP;
                                                 return event;
                                         }
-                                        
-                                }
-                                else {
+                                } else {
                                         gettimeofday(&stv, NULL);
-                                        trace->start_ts = stv.tv_sec + ((double)stv.tv_usec / 1000000.0);
-                                        trace->last_ts = ts;
+                                        // work out the difference between the start of trace replay,
+                                        // and the first packet in the trace
+                                        trace->tdelta = stv.tv_sec + ((double)stv.tv_usec / 1000000.0);
+                                        trace->tdelta -= ts;
+
                                 }
                                 
+                                        // This is the first packet, so just fire away.
                                 packet->size = trace->packet.size;
                                 memcpy(packet->buffer,trace->packet.buffer,trace->packet.size);
@@ -1557 +1562 @@
                                 event.type = TRACE_EVENT_PACKET;
                                 
-                                gettimeofday(&stv, NULL);
-                                trace->start_ts = stv.tv_sec + ((double)stv.tv_usec / 1000000.0);
-                                trace->last_ts = ts;
-                                
+                                trace->trace_last_ts = ts;
+
                                 return event;
                         }