1 files changed, 154 insertions, 0 deletions
diff --git a/src/vm/eventpipe.h b/src/vm/eventpipe.h
new file mode 100644
index 0000000000..2978412325
--- /dev/null
+++ b/src/vm/eventpipe.h
@@ -0,0 +1,154 @@
+// 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.
+
+#ifndef __EVENTPIPE_H__
+#define __EVENTPIPE_H__
+
+#include "common.h"
+
+class EventPipeJsonFile;
+
+// The data fields common to every event.
+struct CommonEventFields
+{
+    // Timestamp generated by QueryPerformanceCounter.
+    LARGE_INTEGER TimeStamp;
+
+    // Thread ID.
+    DWORD ThreadID;
+};
+
+class StackContents
+{
+private:
+
+    const static unsigned int MAX_STACK_DEPTH = 100;
+
+    // Array of IP values from a stack crawl.
+    // Top of stack is at index 0.
+    UINT_PTR m_stackFrames[MAX_STACK_DEPTH];
+
+    // Parallel array of MethodDesc pointers.
+    // Used for debug-only stack printing.
+    MethodDesc* m_methods[MAX_STACK_DEPTH];
+
+    // The next available slot in StackFrames.
+    unsigned int m_nextAvailableFrame;
+
+public:
+
+    StackContents()
+    {
+        LIMITED_METHOD_CONTRACT;
+
+        Reset();
+    }
+
+    void Reset()
+    {
+        LIMITED_METHOD_CONTRACT;
+
+        m_nextAvailableFrame = 0;
+    }
+
+    bool IsEmpty()
+    {
+        LIMITED_METHOD_CONTRACT;
+
+        return (m_nextAvailableFrame == 0);
+    }
+
+    unsigned int GetLength()
+    {
+        LIMITED_METHOD_CONTRACT;
+
+        return m_nextAvailableFrame;
+    }
+
+    UINT_PTR GetIP(unsigned int frameIndex)
+    {
+        LIMITED_METHOD_CONTRACT;
+        _ASSERTE(frameIndex < MAX_STACK_DEPTH);
+
+        if (frameIndex >= MAX_STACK_DEPTH)
+        {
+            return 0;
+        }
+
+        return m_stackFrames[frameIndex];
+    }
+
+    MethodDesc* GetMethod(unsigned int frameIndex)
+    {
+        LIMITED_METHOD_CONTRACT;
+        _ASSERTE(frameIndex < MAX_STACK_DEPTH);
+
+        if (frameIndex >= MAX_STACK_DEPTH)
+        {
+            return NULL;
+        }
+
+        return m_methods[frameIndex];
+    }
+
+    void Append(UINT_PTR controlPC, MethodDesc *pMethod)
+    {
+        LIMITED_METHOD_CONTRACT;
+
+        if(m_nextAvailableFrame < MAX_STACK_DEPTH)
+        {
+            m_stackFrames[m_nextAvailableFrame] = controlPC;
+            m_methods[m_nextAvailableFrame] = pMethod;
+            m_nextAvailableFrame++;
+        }
+    }
+};
+
+class EventPipe
+{
+    public:
+
+        // Initialize the event pipe.
+        static void Initialize();
+
+        // Shutdown the event pipe.
+        static void Shutdown();
+
+        // Enable tracing from the start-up path based on COMPLUS variable.
+        static void EnableOnStartup();
+
+        // Enable tracing via the event pipe.
+        static void Enable();
+
+        // Disable tracing via the event pipe.
+        static void Disable();
+
+        // Determine whether or not the specified provider/keyword combination is enabled.
+        static bool EventEnabled(GUID& providerID, INT64 keyword);
+
+        // Write out an event.  The event is identified by the providerID/eventID pair.
+        // Data is written as a serialized blob matching the ETW serialization conventions.
+        static void WriteEvent(GUID& providerID, INT64 eventID, BYTE *pData, size_t length, bool sampleStack);
+
+        // Write out a sample profile event with the specified stack.
+        static void WriteSampleProfileEvent(Thread *pThread, StackContents &stackContents);
+        
+        // Get the managed call stack for the current thread.
+        static bool WalkManagedStackForCurrentThread(StackContents &stackContents);
+
+        // Get the managed call stack for the specified thread.
+        static bool WalkManagedStackForThread(Thread *pThread, StackContents &stackContents);
+
+    private:
+
+        // Callback function for the stack walker.  For each frame walked, this callback is invoked.
+        static StackWalkAction StackWalkCallback(CrawlFrame *pCf, StackContents *pData);
+
+        static CrstStatic s_initCrst;
+        static bool s_tracingInitialized;
+        static bool s_tracingEnabled;
+        static EventPipeJsonFile *s_pJsonFile;
+};
+
+#endif // __EVENTPIPE_H__