util: Move the existing systemc example into a subdirectory.

This example is for how to embed gem5 within systemc and make it use
the systemc event queue. This used to be the only method of using
gem5 and systemc together, but now that there are other options, it's
ambiguous to have it as the only thing in the util/systemc directory.

This change moves it into a gem5_within_systemc subdirectory which
clearly shows what type of integration that example corresponds with.

Change-Id: I426d68ccb618397d820bef492cbb1ff8ef4a979b
Reviewed-on: https://gem5-review.googlesource.com/c/13375
Reviewed-by: Gabe Black <gabeblack@google.com>
Maintainer: Gabe Black <gabeblack@google.com>

1 files changed, 152 insertions, 0 deletions

diff --git a/util/systemc/gem5_within_systemc/sc_logger.cc b/util/systemc/gem5_within_systemc/sc_logger.cc
new file mode 100644
index 000000000..a8b9020f4
--- /dev/null
+++ b/util/systemc/gem5_within_systemc/sc_logger.cc
@@ -0,0 +1,152 @@
+/*
+ * Copyright (c) 2014 ARM Limited
+ * All rights reserved
+ *
+ * The license below extends only to copyright in the software and shall
+ * not be construed as granting a license to any other intellectual
+ * property including but not limited to intellectual property relating
+ * to a hardware implementation of the functionality of the software
+ * licensed hereunder.  You may use the software subject to the license
+ * terms below provided that you ensure that this notice is replicated
+ * unmodified and in its entirety in all distributions of the software,
+ * modified or unmodified, in source code or in binary form.
+ *
+ * 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: Andrew Bardsley
+ */
+
+/**
+ * @file
+ *
+ * A logger to allow SystemC to capture DPRINTF messages (and similar things)
+ * using sc_report
+ */
+
+#include <cstdlib>
+#include <cstring>
+#include <sstream>
+
+#include "sc_logger.hh"
+
+namespace Gem5SystemC
+{
+
+/** Class to act as a streambuf for std::ostream which cuts output strings
+ *  into lines and offers them to a logger */
+class CuttingStreambuf : public std::streambuf
+{
+  public:
+    /** Accumulate line so far */
+    std::ostringstream line;
+
+    /** Logger to send complete lines to */
+    Trace::Logger *logger;
+
+    CuttingStreambuf(Trace::Logger *logger_) : logger(logger_)
+    { }
+
+    /** Accumulate to line up to \n and then emit */
+    int overflow(int i);
+    int sync();
+
+    /** Push a line out to the logger */
+    void outputLine();
+
+    ~CuttingStreambuf();
+};
+
+void CuttingStreambuf::outputLine()
+{
+    logger->logMessage((Tick)-1, "gem5", line.str());
+    line.clear();
+    line.str("");
+}
+
+/** This is pretty much the least efficient way of doing this, but it has the
+ *  advantage of having very few corners to get wrong.
+ *
+ *  A newly allocated streambuf will have no buffer to serve to its
+ *  [oi]stream.  It will, therefore, call overflow for every character it
+ *  wants to insert into the output stream.  Those characters are captured one
+ *  by one here and added to this->line. */
+int
+CuttingStreambuf::overflow(int chr)
+{
+    if (chr == '\n')
+        outputLine();
+    else if (chr != EOF)
+        line << (char) chr;
+
+    /* Always succeeds */
+    return 0;
+}
+
+int
+CuttingStreambuf::sync()
+{
+    if (!line.str().empty())
+        outputLine();
+
+    /* Always succeeds */
+    return 0;
+}
+
+CuttingStreambuf::~CuttingStreambuf()
+{
+    sync();
+}
+
+Logger::Logger() :
+    cuttingStreambuf(new CuttingStreambuf(this)),
+    stream(cuttingStreambuf)
+{
+}
+
+Logger::~Logger()
+{
+    stream.flush();
+    delete cuttingStreambuf;
+}
+
+/** Log a single message as a single sc_report call */
+void
+Logger::logMessage(Tick when, const std::string &name,
+    const std::string &message)
+{
+    /* Need to chop the newline off the message */
+    std::string message_without_nl = message;
+    message_without_nl.erase(
+        message_without_nl.find_last_not_of(" \n\r") + 1);
+
+    SC_REPORT_INFO(name.c_str(), message_without_nl.c_str());
+}
+
+std::ostream &
+Logger::getOstream()
+{
+    return stream;
+}
+
+}