1 files changed, 131 insertions, 0 deletions
diff --git a/src/vm/eventpipejsonfile.cpp b/src/vm/eventpipejsonfile.cpp
new file mode 100644
index 0000000000..6353c917e7
--- /dev/null
+++ b/src/vm/eventpipejsonfile.cpp
@@ -0,0 +1,131 @@
+// Licensed to the .NET Foundation under one or more agreements.
+// The .NET Foundation licenses this file to you under the MIT license.
+// See the LICENSE file in the project root for more information.
+
+#include "common.h"
+#include "eventpipejsonfile.h"
+
+EventPipeJsonFile::EventPipeJsonFile(SString &outFilePath)
+{
+    CONTRACTL
+    {
+        THROWS;
+        GC_TRIGGERS;
+        MODE_ANY;
+    }
+    CONTRACTL_END;
+
+    m_pFileStream = new CFileStream();
+    if(FAILED(m_pFileStream->OpenForWrite(outFilePath)))
+    {
+        delete(m_pFileStream);
+        m_pFileStream = NULL;
+        return;
+    }
+
+    QueryPerformanceCounter(&m_fileOpenTimeStamp);
+
+    SString fileStart(W("{\n\"StackSource\" : {\n\"Samples\" : [\n"));
+    Write(fileStart);
+}
+
+EventPipeJsonFile::~EventPipeJsonFile()
+{
+    CONTRACTL
+    {
+        THROWS;
+        GC_TRIGGERS;
+        MODE_ANY;
+    }
+    CONTRACTL_END;
+
+    if(m_pFileStream != NULL)
+    {
+        if(!m_writeErrorEncountered)
+        {
+            SString closingString(W("]}}"));
+            Write(closingString);
+        }
+
+        delete(m_pFileStream);
+        m_pFileStream = NULL;
+    }
+}
+
+void EventPipeJsonFile::WriteEvent(CommonEventFields &commonFields, SString &message, StackContents &stackContents)
+{
+    STANDARD_VM_CONTRACT;
+
+    if(m_pFileStream == NULL || m_writeErrorEncountered)
+    {
+        return;
+    }
+
+    // Format the call stack.
+    SString strCallStack;
+    FormatCallStack(stackContents, strCallStack);
+
+    // Convert the timestamp from a QPC value to a trace-relative timestamp.
+    double millisecondsSinceTraceStart = 0.0;
+    if(commonFields.TimeStamp.QuadPart != m_fileOpenTimeStamp.QuadPart)
+    {
+        LARGE_INTEGER elapsedNanoseconds;
+        elapsedNanoseconds.QuadPart = commonFields.TimeStamp.QuadPart - m_fileOpenTimeStamp.QuadPart;
+        millisecondsSinceTraceStart = elapsedNanoseconds.QuadPart / 1000000.0;
+    }
+
+    StackScratchBuffer scratch;
+    SString threadFrame;
+    threadFrame.Printf("Thread (%d)", commonFields.ThreadID);
+    SString event;
+    event.Printf("{\"Time\" : \"%f\", \"Metric\" : \"1\",\n\"Stack\": [\n\"%s\",\n%s\"%s\"]},", millisecondsSinceTraceStart, message.GetANSI(scratch), strCallStack.GetANSI(scratch), threadFrame.GetANSI(scratch));
+    Write(event);
+}
+
+void EventPipeJsonFile::Write(SString &str)
+{
+    CONTRACTL
+    {
+        THROWS;
+        GC_TRIGGERS;
+        MODE_ANY;
+    }
+    CONTRACTL_END;
+
+    StackScratchBuffer scratch;
+    const char * charStr = str.GetANSI(scratch);
+    ULONG inCount = str.GetCount();
+    ULONG outCount;
+    m_pFileStream->Write(charStr, inCount, &outCount);
+
+    if(inCount != outCount)
+    {
+        m_writeErrorEncountered = true;
+    }
+}
+
+void EventPipeJsonFile::FormatCallStack(StackContents &stackContents, SString &resultStr)
+{
+    STANDARD_VM_CONTRACT;
+
+    StackScratchBuffer scratch;
+    SString frameStr;
+    
+    for(unsigned int i=0; i<stackContents.GetLength(); i++)
+    {
+        // Get the method declaration string.
+        MethodDesc *pMethod = stackContents.GetMethod(i);
+        _ASSERTE(pMethod != NULL);
+
+        SString mAssemblyName;
+        mAssemblyName.SetUTF8(pMethod->GetLoaderModule()->GetAssembly()->GetSimpleName());
+        SString fullName;
+        TypeString::AppendMethodInternal(
+            fullName,
+            pMethod,
+            TypeString::FormatNamespace | TypeString::FormatSignature);
+
+        frameStr.Printf("\"%s!%s\",\n", mAssemblyName.GetANSI(scratch), fullName.GetANSI(scratch));
+        resultStr.Append(frameStr);
+    }
+}