base: refactor process class (specifically FdMap and friends)

This patch extends the previous patch's alterations around fd_map.  It cleans
up some of the uglier code in the process file and replaces it with a more
concise C++11 version.  As part of the changes, the FdMap class is pulled out
of the Process class and receives its own file.

1 files changed, 92 insertions, 0 deletions

diff --git a/src/sim/fd_entry.hh b/src/sim/fd_entry.hh
new file mode 100644
index 000000000..e0fd0b0a2
--- /dev/null
+++ b/src/sim/fd_entry.hh
@@ -0,0 +1,92 @@
+/*
+ * Copyright (c) 2015 Advanced Micro Devices, Inc.
+ * Copyright (c) 2001-2005 The Regents of The University of Michigan
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are
+ * met: redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer;
+ * 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;
+ * neither the name of the copyright holders 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
+ * OWNER 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.
+ *
+ * Authors: Nathan Binkert
+ *          Steve Reinhardt
+ */
+
+#ifndef __FD_ENTRY_HH__
+#define __FD_ENTRY_HH__
+
+#include <ostream>
+#include <string>
+
+#include "sim/emul_driver.hh"
+
+/**
+ * FDEntry is used to manage a single file descriptor mapping and metadata
+ * for processes.
+ * Note that the fields are all declared publicly since system calls have a
+ * habit of only needing to access a single field at a time and accessor
+ * methods seem like overkill.
+ */
+class FDEntry : public Serializable
+{
+  public:
+    /**
+     * Constructor contains default values
+     * The file descriptor is free.
+     */
+    FDEntry()
+        : fd(-1), mode(0), flags(0), isPipe(false), readPipeSource(0),
+          fileOffset(0), filename(""), driver(NULL)
+    { }
+
+    void serialize(CheckpointOut &cp) const M5_ATTR_OVERRIDE;
+    void unserialize(CheckpointIn &cp) M5_ATTR_OVERRIDE;
+
+    /**
+     * Check if the target file descriptor is in use.
+     * @return value denoting if target file descriptor already used
+     */
+    bool isFree();
+
+    /**
+     * Fill in members for this file descriptor entry.
+     * @param sim_fd host file descriptor
+     * @param name filename string
+     * @param flags current flags of the file descriptor
+     * @param mode current mode of the file descriptor
+     * @param pipe denotes whether the file descriptor belongs to a pipe
+     */
+    void set(int sim_fd, const std::string name, int flags, int mode,
+             bool pipe);
+
+    /** Reset members to their default values. */
+    void reset();
+
+    int fd;
+    int mode;
+    int flags;
+    bool isPipe;
+    int readPipeSource;
+    uint64_t fileOffset;
+    std::string filename;
+    EmulatedDriver *driver;
+};
+
+#endif // __FD_ENTRY_HH__