//============================================================================
// This file replaces the hand-maintained stub that used to implement clr.dll.
// This is a line-by-line port from IL back to C#.
// We now use RGiesecke.DllExport on the required static init method so it can be
// loaded by a standard CPython interpreter as an extension module. When it
// is loaded, it bootstraps the managed runtime integration layer and defers
// to it to do initialization and put the clr module into sys.modules, etc.
// The "USE_PYTHON_RUNTIME_*" defines control what extra evidence is used
// to help the CLR find the appropriate Python.Runtime assembly.
// If defined, the "pythonRuntimeVersionString" variable must be set to
// Python.Runtime's current version.
#define USE_PYTHON_RUNTIME_VERSION
// If defined, the "PythonRuntimePublicKeyTokenData" data array must be
// set to Python.Runtime's public key token. (sn -T Python.Runtin.dll)
#define USE_PYTHON_RUNTIME_PUBLIC_KEY_TOKEN
// If DEBUG is defined in the Build Properties, a few Console.WriteLine
// calls are made to indicate what's going on during the load...
//============================================================================
using System;
using System.Diagnostics;
using System.Globalization;
using System.IO;
using System.Reflection;
using System.Runtime.InteropServices;
using RGiesecke.DllExport;
public class clrModule
{
#if PYTHON3
[DllExport("PyInit_clr", CallingConvention.StdCall)]
public static IntPtr PyInit_clr()
#elif PYTHON2
[DllExport("initclr", CallingConvention.StdCall)]
public static void initclr()
#endif
{
DebugPrint("Attempting to load 'Python.Runtime' using standard binding rules.");
#if USE_PYTHON_RUNTIME_PUBLIC_KEY_TOKEN
var pythonRuntimePublicKeyTokenData = new byte[] { 0x50, 0x00, 0xfe, 0xa6, 0xcb, 0xa7, 0x02, 0xdd };
#endif
// Attempt to find and load Python.Runtime using standard assembly binding rules.
// This roughly translates into looking in order:
// - GAC
// - ApplicationBase
// - A PrivateBinPath under ApplicationBase
// With an unsigned assembly, the GAC is skipped.
var pythonRuntimeName = new AssemblyName("Python.Runtime")
{
#if USE_PYTHON_RUNTIME_VERSION
// Has no effect until SNK works. Keep updated anyways.
Version = new Version("2.4.0"),
#endif
CultureInfo = CultureInfo.InvariantCulture
};
#if USE_PYTHON_RUNTIME_PUBLIC_KEY_TOKEN
pythonRuntimeName.SetPublicKeyToken(pythonRuntimePublicKeyTokenData);
#endif
// We've got the AssemblyName with optional features; try to load it.
Assembly pythonRuntime;
try
{
pythonRuntime = Assembly.Load(pythonRuntimeName);
DebugPrint("Success loading 'Python.Runtime' using standard binding rules.");
}
catch (IOException)
{
DebugPrint("'Python.Runtime' not found using standard binding rules.");
try
{
// If the above fails for any reason, we fallback to attempting to load "Python.Runtime.dll"
// from the directory this assembly is running in. "This assembly" is probably "clr.pyd",
// sitting somewhere in PYTHONPATH. This is using Assembly.LoadFrom, and inherits all the
// caveats of that call. See MSDN docs for details.
// Suzanne Cook's blog is also an excellent source of info on this:
// http://blogs.msdn.com/suzcook/
// http://blogs.msdn.com/suzcook/archive/2003/05/29/57143.aspx
// http://blogs.msdn.com/suzcook/archive/2003/06/13/57180.aspx
Assembly executingAssembly = Assembly.GetExecutingAssembly();
string assemblyDirectory = Path.GetDirectoryName(executingAssembly.Location);
if (assemblyDirectory == null)
{
throw new InvalidOperationException(executingAssembly.Location);
}
string pythonRuntimeDllPath = Path.Combine(assemblyDirectory, "Python.Runtime.dll");
DebugPrint($"Attempting to load Python.Runtime from: '{pythonRuntimeDllPath}'.");
pythonRuntime = Assembly.LoadFrom(pythonRuntimeDllPath);
DebugPrint($"Success loading 'Python.Runtime' from: '{pythonRuntimeDllPath}'.");
}
catch (InvalidOperationException)
{
DebugPrint("Could not load 'Python.Runtime'.");
#if PYTHON3
return IntPtr.Zero;
#elif PYTHON2
return;
#endif
}
}
// Once here, we've successfully loaded SOME version of Python.Runtime
// So now we get the PythonEngine and execute the InitExt method on it.
Type pythonEngineType = pythonRuntime.GetType("Python.Runtime.PythonEngine");
#if PYTHON3
return (IntPtr)pythonEngineType.InvokeMember("InitExt", BindingFlags.InvokeMethod, null, null, null);
#elif PYTHON2
pythonEngineType.InvokeMember("InitExt", BindingFlags.InvokeMethod, null, null, null);
#endif
}
///
/// Substitute for Debug.Writeline(...). Ideally we would use Debug.Writeline
/// but haven't been able to configure the TRACE from within Python.
///
[Conditional("DEBUG")]
private static void DebugPrint(string str)
{
Console.WriteLine(str);
}
}