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diff --git a/src/sim/fd_array.hh b/src/sim/fd_array.hh
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+/*
+ * Copyright (c) 2016 Advanced Micro Devices, Inc.
+ * All rights reserved.
+ *
+ * For use for simulation and test purposes only
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice,
+ * this list of conditions and the following disclaimer.
+ *
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ * this list of conditions and the following disclaimer in the documentation
+ * and/or other materials provided with the distribution.
+ *
+ * 3. Neither the name of the copyright holder nor the names of its
+ * contributors may be used to endorse or promote products derived from this
+ * software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
+ * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ *
+ * Author: Brandon Potter
+ */
+
+#ifndef __FD_ARRAY_HH__
+#define __FD_ARRAY_HH__
+
+#include <array>
+#include <memory>
+#include <string>
+
+#include "sim/fd_entry.hh"
+
+class FDArray
+{
+  private:
+    static const int NUM_FDS = 1024;
+
+  public:
+    /**
+     * Initialize the file descriptor array and set the standard file
+     * descriptors to defaults or values passed in with the process
+     * params.
+     * @param input Used to initialize the stdin file descriptor
+     * @param output Used to initialize the stdout file descriptor
+     * @param errout Used to initialize the stderr file descriptor
+     */
+    FDArray(std::string const& input, std::string const& output,
+            std::string const& errout);
+
+    std::string _input;
+    std::string _output;
+    std::string _errout;
+
+    /**
+     * Figure out the file offsets for all currently open files and save them
+     * the offsets during the calls to drain by the owning process.
+     */
+    void updateFileOffsets();
+
+    /**
+     * Restore all offsets for currently open files during the unserialize
+     * phase for the owning process class.
+     */
+    void restoreFileOffsets();
+
+    /**
+     * Treat this object like a normal array in using the subscript operator
+     * to pull entries out of it.
+     * @param tgt_fd Use target file descriptors to index the array.
+     */
+    inline std::shared_ptr<FDEntry>
+    operator[](int tgt_fd)
+    {
+        return getFDEntry(tgt_fd);
+    }
+
+    /**
+     * Step through the file descriptor array and find the first available
+     * entry which is denoted as being free by being a 'nullptr'. That file
+     * descriptor entry is the new target file descriptor entry that we
+     * return as the return parameter.
+     * @param fdp Allocated beforehand and passed into this method;
+     * the fdp is meant to be a generic pointer capable of pointing to
+     * different types of file descriptors. Must cast the pointer to the
+     * correct type before dereferencing to access the needed fields.
+     */
+    int allocFD(std::shared_ptr<FDEntry> fdp);
+
+    /**
+     * Return the size of the _fdArray field
+     */
+    int getSize() const { return _fdArray.size(); }
+
+    /**
+     * Try to close the host file descriptor. If successful, set the
+     * specified file descriptor entry object pointer to nullptr.
+     * Used to "close" the target file descriptor.
+     * @param tgt_fd Use target file descriptors to index the array.
+     */
+    int closeFDEntry(int tgt_fd);
+
+  private:
+    /**
+     * Help clarify our intention when opening files in the init and
+     * restoration code. These are helper functions which are not meant to
+     * be exposed to other objects or files.
+     */
+    int openFile(std::string const& file_name, int flags, mode_t mode) const;
+    int openInputFile(std::string const& file_name) const;
+    int openOutputFile(std::string const& file_name) const;
+
+    /**
+     * Return the file descriptor entry object associated with the index
+     * provided. (The index is protected with bounds checking on the array
+     * size without the use of the array's at operator.)
+     * @param tgt_fd Use target file descriptors to index the array.
+     */
+    std::shared_ptr<FDEntry> getFDEntry(int tgt_fd);
+
+    /**
+     * Hold pointers to the file descriptor entries. The array size is
+     * statically defined by the operating system.
+     */
+    std::array<std::shared_ptr<FDEntry>, NUM_FDS> _fdArray;
+
+    /**
+     * Hold strings which represent the default values which are checked
+     * against to initialize the standard file descriptors. If the string
+     * provided doesn't hit against these maps, then a file is opened on the
+     * host instead of using the host's standard file descriptors.
+     */
+    std::map<std::string, int> imap;
+    std::map<std::string, int> oemap;
+};
+
+#endif // __FD_ARRAY_HH__