Added support for .NET Core 3.x+ core dump generation that results in… (

#67)

* Added support for .NET Core 3.x+ core dump generation that results in more manageable core dump sizes

* Fixed Valgrind error - uninitialized memory block

* Fixed Valgrind - memory leak

* Fixed review feedback

* Fixed PR feedback

include/CoreDumpWriter.h

@@ -16,6 +16,9 @@
 #include <signal.h>
 #include <unistd.h>
 #include <sys/wait.h>
+#include <sys/socket.h>
+#include <sys/un.h>
+#include <stdint.h>
 
 #include "Handle.h"
 #include "ProcDumpConfiguration.h"
@@ -24,6 +27,33 @@
 #define MAX_LINES 15
 #define BUFFER_LENGTH 1024
 
+#define CORECLR_DUMPTYPE_FULL 4
+#define CORECLR_DUMPLOGGING_OFF 0
+#define CORECLR_DIAG_IPCHEADER_SIZE 24
+
+// Magic version for the IpcHeader struct
+struct MagicVersion
+{
+    uint8_t Magic[14];
+};
+
+// The header to be associated with every command and response
+// to/from the diagnostics server
+struct IpcHeader
+{
+    union
+    {
+        struct MagicVersion _magic;
+        uint8_t  Magic[14];  // Magic Version number
+    };
+
+    uint16_t Size;       // The size of the incoming packet, size = header + payload size
+    uint8_t  CommandSet; // The scope of the Command.
+    uint8_t  CommandId;  // The command being sent
+    uint16_t Reserved;   // reserved for future use
+};
+
+
 enum ECoreDumpType {
     COMMIT,
     CPU,