using System;
using System.IO;
using System.Threading;
using System.Reflection;
namespace Python.Runtime
{
///
/// This class provides the public interface of the Python runtime.
///
public class PythonEngine
{
private static DelegateManager delegateManager;
private static bool initialized;
#region Properties
public static bool IsInitialized
{
get { return initialized; }
}
internal static DelegateManager DelegateManager
{
get
{
if (delegateManager == null)
{
throw new InvalidOperationException(
"DelegateManager has not yet been initialized using Python.Runtime.PythonEngine.Initialize().");
}
return delegateManager;
}
}
public static string ProgramName
{
get
{
string result = Runtime.Py_GetProgramName();
if (result == null)
{
return "";
}
return result;
}
set { Runtime.Py_SetProgramName(value); }
}
public static string PythonHome
{
get
{
string result = Runtime.Py_GetPythonHome();
if (result == null)
{
return "";
}
return result;
}
set { Runtime.Py_SetPythonHome(value); }
}
public static string PythonPath
{
get
{
string result = Runtime.Py_GetPath();
if (result == null)
{
return "";
}
return result;
}
set { Runtime.Py_SetPath(value); }
}
public static string Version
{
get { return Runtime.Py_GetVersion(); }
}
public static string BuildInfo
{
get { return Runtime.Py_GetBuildInfo(); }
}
public static string Platform
{
get { return Runtime.Py_GetPlatform(); }
}
public static string Copyright
{
get { return Runtime.Py_GetCopyright(); }
}
public static int RunSimpleString(string code)
{
return Runtime.PyRun_SimpleString(code);
}
#endregion
///
/// Initialize Method
///
///
///
/// Initialize the Python runtime. It is safe to call this method
/// more than once, though initialization will only happen on the
/// first call. It is *not* necessary to hold the Python global
/// interpreter lock (GIL) to call this method.
///
public static void Initialize()
{
if (!initialized)
{
// Creating the delegateManager MUST happen before Runtime.Initialize
// is called. If it happens afterwards, DelegateManager's CodeGenerator
// throws an exception in its ctor. This exception is eaten somehow
// during an initial "import clr", and the world ends shortly thereafter.
// This is probably masking some bad mojo happening somewhere in Runtime.Initialize().
delegateManager = new DelegateManager();
Runtime.Initialize();
initialized = true;
Exceptions.Clear();
// register the atexit callback (this doesn't use Py_AtExit as the C atexit
// callbacks are called after python is fully finalized but the python ones
// are called while the python engine is still running).
string code =
"import atexit, clr\n" +
"atexit.register(clr._AtExit)\n";
PyObject r = PythonEngine.RunString(code);
if (r != null)
r.Dispose();
// Load the clr.py resource into the clr module
IntPtr clr = Python.Runtime.ImportHook.GetCLRModule();
IntPtr clr_dict = Runtime.PyModule_GetDict(clr);
PyDict locals = new PyDict();
try
{
IntPtr module = Runtime.PyImport_AddModule("clr._extras");
IntPtr module_globals = Runtime.PyModule_GetDict(module);
IntPtr builtins = Runtime.PyEval_GetBuiltins();
Runtime.PyDict_SetItemString(module_globals, "__builtins__", builtins);
var assembly = Assembly.GetExecutingAssembly();
using (Stream stream = assembly.GetManifestResourceStream("clr.py"))
using (StreamReader reader = new StreamReader(stream))
{
// add the contents of clr.py to the module
string clr_py = reader.ReadToEnd();
PyObject result = RunString(clr_py, module_globals, locals.Handle);
if (null == result)
throw new PythonException();
result.Dispose();
}
// add the imported module to the clr module, and copy the API functions
// and decorators into the main clr module.
Runtime.PyDict_SetItemString(clr_dict, "_extras", module);
foreach (PyObject key in locals.Keys())
{
if (!key.ToString().StartsWith("_"))
{
PyObject value = locals[key];
Runtime.PyDict_SetItem(clr_dict, key.Handle, value.Handle);
value.Dispose();
}
key.Dispose();
}
}
finally
{
locals.Dispose();
}
}
}
//====================================================================
// A helper to perform initialization from the context of an active
// CPython interpreter process - this bootstraps the managed runtime
// when it is imported by the CLR extension module.
//====================================================================
#if (PYTHON32 || PYTHON33 || PYTHON34 || PYTHON35)
public static IntPtr InitExt() {
#else
public static void InitExt()
{
#endif
try
{
Initialize();
// Trickery - when the import hook is installed into an already
// running Python, the standard import machinery is still in
// control for the duration of the import that caused bootstrap.
//
// That is problematic because the std machinery tries to get
// sub-names directly from the module __dict__ rather than going
// through our module object's getattr hook. This workaround is
// evil ;) We essentially climb up the stack looking for the
// import that caused the bootstrap to happen, then re-execute
// the import explicitly after our hook has been installed. By
// doing this, the original outer import should work correctly.
//
// Note that this is only needed during the execution of the
// first import that installs the CLR import hook. This hack
// still doesn't work if you use the interactive interpreter,
// since there is no line info to get the import line ;(
string code =
"import traceback\n" +
"for item in traceback.extract_stack():\n" +
" line = item[3]\n" +
" if line is not None:\n" +
" if line.startswith('import CLR') or \\\n" +
" line.startswith('import clr') or \\\n" +
" line.startswith('from clr') or \\\n" +
" line.startswith('from CLR'):\n" +
" exec(line)\n" +
" break\n";
PyObject r = PythonEngine.RunString(code);
if (r != null)
{
r.Dispose();
}
}
catch (PythonException e)
{
e.Restore();
#if (PYTHON32 || PYTHON33 || PYTHON34 || PYTHON35)
return IntPtr.Zero;
#endif
}
#if (PYTHON32 || PYTHON33 || PYTHON34 || PYTHON35)
return Python.Runtime.ImportHook.GetCLRModule();
#endif
}
///
/// Shutdown Method
///
///
///
/// Shutdown and release resources held by the Python runtime. The
/// Python runtime can no longer be used in the current process
/// after calling the Shutdown method.
///
public static void Shutdown()
{
if (initialized)
{
Runtime.Shutdown();
initialized = false;
}
}
///
/// AcquireLock Method
///
///
///
/// Acquire the Python global interpreter lock (GIL). Managed code
/// *must* call this method before using any objects or calling any
/// methods on objects in the Python.Runtime namespace. The only
/// exception is PythonEngine.Initialize, which may be called without
/// first calling AcquireLock.
///
/// Each call to AcquireLock must be matched by a corresponding call
/// to ReleaseLock, passing the token obtained from AcquireLock.
///
/// For more information, see the "Extending and Embedding" section
/// of the Python documentation on www.python.org.
///
public static IntPtr AcquireLock()
{
return Runtime.PyGILState_Ensure();
}
///
/// ReleaseLock Method
///
///
///
/// Release the Python global interpreter lock using a token obtained
/// from a previous call to AcquireLock.
///
/// For more information, see the "Extending and Embedding" section
/// of the Python documentation on www.python.org.
///
public static void ReleaseLock(IntPtr gs)
{
Runtime.PyGILState_Release(gs);
}
///
/// BeginAllowThreads Method
///
///
///
/// Release the Python global interpreter lock to allow other threads
/// to run. This is equivalent to the Py_BEGIN_ALLOW_THREADS macro
/// provided by the C Python API.
///
/// For more information, see the "Extending and Embedding" section
/// of the Python documentation on www.python.org.
///
public static IntPtr BeginAllowThreads()
{
return Runtime.PyEval_SaveThread();
}
///
/// EndAllowThreads Method
///
///
///
/// Re-aquire the Python global interpreter lock for the current
/// thread. This is equivalent to the Py_END_ALLOW_THREADS macro
/// provided by the C Python API.
///
/// For more information, see the "Extending and Embedding" section
/// of the Python documentation on www.python.org.
///
public static void EndAllowThreads(IntPtr ts)
{
Runtime.PyEval_RestoreThread(ts);
}
///
/// ImportModule Method
///
///
///
/// Given a fully-qualified module or package name, import the
/// module and return the resulting module object as a PyObject
/// or null if an exception is raised.
///
public static PyObject ImportModule(string name)
{
IntPtr op = Runtime.PyImport_ImportModule(name);
if (op == IntPtr.Zero)
{
return null;
}
return new PyObject(op);
}
///
/// ReloadModule Method
///
///
///
/// Given a PyObject representing a previously loaded module, reload
/// the module.
///
public static PyObject ReloadModule(PyObject module)
{
IntPtr op = Runtime.PyImport_ReloadModule(module.Handle);
if (op == IntPtr.Zero)
{
throw new PythonException();
}
return new PyObject(op);
}
///
/// ModuleFromString Method
///
///
///
/// Given a string module name and a string containing Python code,
/// execute the code in and return a module of the given name.
///
public static PyObject ModuleFromString(string name, string code)
{
IntPtr c = Runtime.Py_CompileString(code, "none", (IntPtr)257);
if (c == IntPtr.Zero)
{
throw new PythonException();
}
IntPtr m = Runtime.PyImport_ExecCodeModule(name, c);
if (m == IntPtr.Zero)
{
throw new PythonException();
}
return new PyObject(m);
}
///
/// RunString Method
///
///
///
/// Run a string containing Python code. Returns the result of
/// executing the code string as a PyObject instance, or null if
/// an exception was raised.
///
public static PyObject RunString(string code)
{
IntPtr globals = Runtime.PyEval_GetGlobals();
IntPtr locals = Runtime.PyDict_New();
IntPtr builtins = Runtime.PyEval_GetBuiltins();
Runtime.PyDict_SetItemString(locals, "__builtins__", builtins);
IntPtr flag = (IntPtr)257; /* Py_file_input */
IntPtr result = Runtime.PyRun_String(code, flag, globals, locals);
Runtime.Decref(locals);
if (result == IntPtr.Zero)
{
return null;
}
return new PyObject(result);
}
public static PyObject RunString(string code, IntPtr globals, IntPtr locals)
{
IntPtr flag = (IntPtr)257; /* Py_file_input */
IntPtr result = Runtime.PyRun_String(code, flag, globals, locals);
if (result == IntPtr.Zero)
{
return null;
}
return new PyObject(result);
}
}
public static class Py
{
public static GILState GIL()
{
if (!PythonEngine.IsInitialized)
PythonEngine.Initialize();
return new GILState();
}
public class GILState : IDisposable
{
private IntPtr state;
internal GILState()
{
state = PythonEngine.AcquireLock();
}
public void Dispose()
{
PythonEngine.ReleaseLock(state);
GC.SuppressFinalize(this);
}
~GILState()
{
Dispose();
}
}
public class KeywordArguments : PyDict
{
}
public static KeywordArguments kw(params object[] kv)
{
var dict = new KeywordArguments();
if (kv.Length%2 != 0)
throw new ArgumentException("Must have an equal number of keys and values");
for (int i = 0; i < kv.Length; i += 2)
{
IntPtr value;
if (kv[i + 1] is PyObject)
value = ((PyObject)kv[i + 1]).Handle;
else
value = Converter.ToPython(kv[i + 1], kv[i + 1]?.GetType());
if (Runtime.PyDict_SetItemString(dict.Handle, (string)kv[i], value) != 0)
throw new ArgumentException(string.Format("Cannot add key '{0}' to dictionary.", (string)kv[i]));
if (!(kv[i + 1] is PyObject))
Runtime.Decref(value);
}
return dict;
}
public static PyObject Import(string name)
{
return PythonEngine.ImportModule(name);
}
}
}