Add -offsetTime parameter for LTTNG plugin to offset event by the specified number of nanoseconds (#99)

* Add -offsetTime parameter for LTTNG plugin to offset all LTTngEvent instances by the specified number of nanoseconds
* Bump LTTngCds and CtfPlayback patch versions

Author: jamesdooleymsft

CtfPlayback/CtfPlayback.csproj

@@ -2,7 +2,7 @@
 
   <PropertyGroup>
     <TargetFramework>netstandard2.1</TargetFramework>
-	<Version>1.2.1</Version>
+	<Version>1.2.2</Version>
     <PackageRequireLicenseAcceptance>true</PackageRequireLicenseAcceptance>
     <Authors>Microsoft</Authors>
     <Company>Microsoft Corp.</Company>

CtfPlayback/FieldValues/CtfTimestamp.cs

@@ -87,9 +87,34 @@ public CtfTimestamp(ICtfMetadataCustomization metadataCustomization, ICtfMetadat
             if (timestampValue < 0)
             {
                 throw new ArgumentException("Negative timestamp value is not supported.", nameof(timestampValue));
+            }
+
+            this.NanosecondsFromClockBase = ConvertTimeToNanoseconds((ulong)timestampValue);
+        }
+
+        /// <summary>
+        /// Constructor
+        /// </summary>
+        /// <param name="integerValue">Integer representation of the timestamp</param>
+        /// <param name="timestampValue">Timestamp value in units specified by the ClockDescriptor</param>
+        public CtfTimestamp(CtfIntegerValue integerValue, long timestampValue, ICtfClockDescriptor clockDescriptor, string clockName)
+        {
+            if (timestampValue < 0)
+            {
+                throw new ArgumentException("Negative timestamp value is not supported.", nameof(timestampValue));
+            }
+            this.BaseIntegerValue = integerValue;
+            this.ClockDescriptor = clockDescriptor;
+
+            if (!this.BaseIntegerValue.Value.TryGetInt64(out long value))
+            {
+                throw new CtfPlaybackException("Unable to retrieve timestamp as long.");
             }
 
-            this.NanosecondsFromClockBase = ConvertTimeToNanoseconds((ulong) timestampValue);
+            this.NanosecondsFromClockBase = ConvertTimeToNanoseconds((ulong)timestampValue);
+
+            this.ClockName = clockName;
+            this.ClockOffsetFromPosixEpochInNanoseconds = ConvertTimeToNanoseconds(this.ClockDescriptor.Offset);
         }
 
         /// <summary>

LTTngCds/CookerData/LTTngEvent.cs

@@ -18,7 +18,8 @@ public class LTTngEvent
         : IKeyedDataType<string>
     {
         private readonly ICtfEvent ctfEvent;
-        private readonly IEventDescriptor eventDescriptor;
+        private readonly IEventDescriptor eventDescriptor;
+        private readonly CtfTimestamp adjustedCtfTimestamp;
 
         internal LTTngEvent(ICtfEvent ctfEvent)
         {
@@ -39,8 +40,13 @@ internal LTTngEvent(ICtfEvent ctfEvent)
 
             this.ctfEvent = ctfEvent;
             this.eventDescriptor = eventDescriptor;
+        }
 
-  ///          streamDefinedEventContext
+        internal LTTngEvent(LTTngEvent lttngEvent, long timestampAdjustmentNano) : this(lttngEvent.ctfEvent)
+        {
+            long adjustedTimestamp = Math.Max(0, (long)lttngEvent.ctfEvent.Timestamp.NanosecondsFromClockBase + timestampAdjustmentNano);
+            CtfTimestamp origCtfTimestamp = lttngEvent.ctfEvent.Timestamp;
+            this.adjustedCtfTimestamp = new CtfTimestamp(origCtfTimestamp.BaseIntegerValue, adjustedTimestamp, origCtfTimestamp.ClockDescriptor, origCtfTimestamp.ClockName);
         }
 
         /// <summary>
@@ -56,18 +62,18 @@ internal LTTngEvent(ICtfEvent ctfEvent)
         /// <summary>
         /// Event timestamp. Nanoseconds from the CTF clock the timestamp is associated with.
         /// </summary>
-        public Timestamp Timestamp => new Timestamp((long)this.ctfEvent.Timestamp.NanosecondsFromClockBase);
+        public Timestamp Timestamp => new Timestamp((long)(adjustedCtfTimestamp?.NanosecondsFromClockBase ?? this.ctfEvent.Timestamp.NanosecondsFromClockBase));
 
         /// <summary>
         /// Event time as a wall clock.
         /// </summary>
-        public DateTime WallClockTime => this.ctfEvent.Timestamp.GetDateTime();
+        public DateTime WallClockTime => adjustedCtfTimestamp?.GetDateTime() ?? this.ctfEvent.Timestamp.GetDateTime();
 
         /// <summary>
         /// CTF timestamp
         /// </summary>
-        public CtfTimestamp CtfTimestamp => this.ctfEvent.Timestamp;
-
+        public CtfTimestamp CtfTimestamp => adjustedCtfTimestamp ?? this.ctfEvent.Timestamp;
+
         /// <summary>
         /// Event header as defined in the stream for this event.
         /// </summary>

LTTngCds/LTTngCds.csproj

@@ -2,7 +2,7 @@
 
   <PropertyGroup>
     <TargetFramework>netstandard2.1</TargetFramework>
-	<Version>1.2.1</Version>
+	<Version>1.2.2</Version>
     <PackageRequireLicenseAcceptance>true</PackageRequireLicenseAcceptance>
     <Authors>Microsoft</Authors>
     <Company>Microsoft Corp.</Company>

LTTngCds/LTTngDataSource.cs

@@ -22,7 +22,7 @@ public class LTTngDataSource
         private IApplicationEnvironment applicationEnvironment;
 
         /// <inheritdoc />
-        public override IEnumerable<Option> CommandLineOptions => Enumerable.Empty<Option>();
+        public override IEnumerable<Option> CommandLineOptions => new List<Option> { new Option("LTTngOffsetTime", "offsetTime", 1, 1) };
 
         protected override bool IsDataSourceSupportedCore(IDataSource dataSource)
         {
@@ -70,7 +70,7 @@ protected override ICustomDataProcessor CreateProcessorCore(
             Guard.NotNull(processorEnvironment, nameof(processorEnvironment));
             Guard.Any(dataSources, nameof(dataSources));
 
-            var sourceParser = new LTTngSourceParser();
+            var sourceParser = new LTTngSourceParser(options);
 
             var firstDataSource = dataSources.First();
             string sourcePath = firstDataSource.Uri.LocalPath;

LTTngCds/LTTngSourceParser.cs

@@ -5,6 +5,7 @@
 using System.Collections.Generic;
 using System.Diagnostics;
 using System.IO.Compression;
+using System.Linq;
 using System.Threading;
 using CtfPlayback;
 using CtfPlayback.Inputs;
@@ -25,6 +26,20 @@ internal sealed class LTTngSourceParser
     {
         private ICtfInput ctfInput;
         private DataSourceInfo dataSourceInfo;
+        private readonly long timeOffsetNanos = 0;
+
+        public LTTngSourceParser(ProcessorOptions options)
+        {
+            IEnumerable<String> timeOffsetArgs;
+            if (options.Options.TryGetOptionArguments("LTTngOffsetTime", out timeOffsetArgs))
+            {
+                long localOffset = 0;
+                if (long.TryParse(timeOffsetArgs.First(), out localOffset))
+                {
+                    timeOffsetNanos = localOffset;
+                }
+            }
+        }
 
         public void SetZippedInput(string pathToZip)
         {
@@ -79,6 +94,11 @@ public override void ProcessSource(
 
             void EventCallback(LTTngEvent lttngEvent, LTTngContext lttngContext)
             {
+                if (timeOffsetNanos != 0)
+                {
+                    lttngEvent = new LTTngEvent(lttngEvent, timeOffsetNanos);
+                }
+
                 if (this.EventCount == 0)
                 {
                     this.FirstEventTimestamp = lttngEvent.Timestamp;
@@ -134,7 +154,7 @@ void EventCallback(LTTngEvent lttngEvent, LTTngContext lttngContext)
             {
                 throw new Exception("No events - failure processing .ctf");
             }
-        }
+        }
 
         public void Dispose()
         {