libm5: Create a libm5 static library for embedding m5.

This should allow m5 to be more easily embedded into other simulators.
The m5 binary adds a simple main function which then calls into the m5
libarary to start the simulation. In order to make this work
correctly, it was necessary embed python code directly into the
library instead of the zipfile hack.  This is because you can't just
append the zipfile to the end of a library the way you can a binary.
As a result, Python files that are part of the m5 simulator are now
compile, marshalled, compressed, and then inserted into the library's
data section with a certain symbol name.  Additionally, a new Importer
was needed to allow python to get at the embedded python code.

Small additional changes include:
- Get rid of the PYTHONHOME stuff since I don't think anyone ever used
it, and it just confuses things.  Easy enough to add back if I'm wrong.
- Create a few new functions that are key to initializing and running
the simulator: initSignals, initM5Python, m5Main.

The original code for creating libm5 was inspired by a patch Michael
Adler, though the code here was done by me.

1 files changed, 80 insertions, 0 deletions

diff --git a/src/python/importer.py b/src/python/importer.py
new file mode 100644
index 000000000..fe099fdb8
--- /dev/null
+++ b/src/python/importer.py
@@ -0,0 +1,80 @@
+# Copyright (c) 2008 The Hewlett-Packard Development Company
+# All rights reserved.
+#
+# 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
+
+# Simple importer that allows python to import data from a dict of
+# code objects.  The keys are the module path, and the items are the
+# filename and bytecode of the file.
+class CodeImporter(object):
+    def __init__(self):
+        self.modules = {}
+
+    def add_module(self, filename, modpath, code):
+        if modpath in self.modules:
+            raise AttributeError, "%s already found in importer"
+
+        self.modules[modpath] = (filename, code)
+
+    def find_module(self, fullname, path):
+        if fullname in self.modules:
+            return self
+
+        return None
+
+    def load_module(self, fullname):
+        # Because the importer is created and initialized in its own
+        # little sandbox (in init.cc), the globals that were available
+        # when the importer module was loaded and CodeImporter was
+        # defined are not available when load_module is actually
+        # called. Soooo, the imports must live here.
+        import imp
+        import os
+        import sys
+        mod = imp.new_module(fullname)
+        sys.modules[fullname] = mod
+
+        try:
+            mod.__loader__ = self
+            srcfile,code = self.modules[fullname]
+            if os.path.basename(srcfile) == '__init__.py':
+                mod.__path__ = fullname.split('.')
+            mod.__file__ = srcfile
+
+            exec code in mod.__dict__
+        except Exception:
+            del sys.modules[fullname]
+            raise
+
+        return mod
+
+# Create an importer and add it to the meta_path so future imports can
+# use it.  There's currently nothing in the importer, but calls to
+# add_module can be used to add code.
+import sys
+importer = CodeImporter()
+add_module = importer.add_module
+sys.meta_path.append(importer)