using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Diagnostics;
using System.Linq;
using System.Reflection;
using System.Runtime.InteropServices;
using Python.Runtime.Native;
namespace Python.Runtime
{
///
/// This class provides the public interface of the Python runtime.
///
public class PythonEngine : IDisposable
{
private static DelegateManager? delegateManager;
private static bool initialized;
private static IntPtr _pythonHome = IntPtr.Zero;
private static IntPtr _programName = IntPtr.Zero;
private static IntPtr _pythonPath = IntPtr.Zero;
private static InteropConfiguration interopConfiguration = InteropConfiguration.MakeDefault();
public PythonEngine()
{
Initialize();
}
public PythonEngine(params string[] args)
{
Initialize(args);
}
public PythonEngine(IEnumerable args)
{
Initialize(args);
}
public void Dispose()
{
Shutdown();
}
public static bool IsInitialized
{
get { return initialized; }
}
/// Set to true to enable GIL debugging assistance.
public static bool DebugGIL { get; set; } = false;
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 InteropConfiguration InteropConfiguration
{
get => interopConfiguration;
set
{
if (IsInitialized)
throw new NotSupportedException("Changing interop configuration when engine is running is not supported");
interopConfiguration = value ?? throw new ArgumentNullException(nameof(InteropConfiguration));
}
}
public static string ProgramName
{
get
{
IntPtr p = Runtime.TryUsingDll(() => Runtime.Py_GetProgramName());
return UcsMarshaler.PtrToPy3UnicodePy2String(p) ?? "";
}
set
{
Marshal.FreeHGlobal(_programName);
_programName = Runtime.TryUsingDll(
() => UcsMarshaler.Py3UnicodePy2StringtoPtr(value)
);
Runtime.Py_SetProgramName(_programName);
}
}
public static string PythonHome
{
get
{
IntPtr p = Runtime.TryUsingDll(() => Runtime.Py_GetPythonHome());
return UcsMarshaler.PtrToPy3UnicodePy2String(p) ?? "";
}
set
{
// this value is null in the beginning
Marshal.FreeHGlobal(_pythonHome);
_pythonHome = Runtime.TryUsingDll(
() => UcsMarshaler.Py3UnicodePy2StringtoPtr(value)
);
Runtime.Py_SetPythonHome(_pythonHome);
}
}
public static string PythonPath
{
get
{
IntPtr p = Runtime.TryUsingDll(() => Runtime.Py_GetPath());
return UcsMarshaler.PtrToPy3UnicodePy2String(p) ?? "";
}
set
{
Marshal.FreeHGlobal(_pythonPath);
_pythonPath = Runtime.TryUsingDll(
() => UcsMarshaler.Py3UnicodePy2StringtoPtr(value)
);
Runtime.Py_SetPath(_pythonPath);
}
}
public static string Version
{
get { return Marshal.PtrToStringAnsi(Runtime.Py_GetVersion()); }
}
public static string BuildInfo
{
get { return Marshal.PtrToStringAnsi(Runtime.Py_GetBuildInfo()); }
}
public static string Platform
{
get { return Marshal.PtrToStringAnsi(Runtime.Py_GetPlatform()); }
}
public static string Copyright
{
get { return Marshal.PtrToStringAnsi(Runtime.Py_GetCopyright()); }
}
public static string Compiler
{
get { return Marshal.PtrToStringAnsi(Runtime.Py_GetCompiler()); }
}
///
/// Set the NoSiteFlag to disable loading the site module.
/// Must be called before Initialize.
/// https://docs.python.org/3/c-api/init.html#c.Py_NoSiteFlag
///
public static void SetNoSiteFlag()
{
Runtime.SetNoSiteFlag();
}
public static int RunSimpleString(string code)
{
return Runtime.PyRun_SimpleString(code);
}
public static void Initialize()
{
Initialize(setSysArgv: true);
}
public static void Initialize(bool setSysArgv = true, bool initSigs = false)
{
Initialize(Enumerable.Empty(), setSysArgv: setSysArgv, initSigs: initSigs);
}
///
/// 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.
/// initSigs can be set to 1 to do default python signal configuration. This will override the way signals are handled by the application.
///
public static void Initialize(IEnumerable args, bool setSysArgv = true, bool initSigs = false)
{
if (initialized)
{
return;
}
// 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(initSigs);
initialized = true;
Exceptions.Clear();
// Make sure we clean up properly on app domain unload.
AppDomain.CurrentDomain.DomainUnload += OnDomainUnload;
AppDomain.CurrentDomain.ProcessExit += OnProcessExit;
if (setSysArgv)
{
Py.SetArgv(args);
}
// Load the clr.py resource into the clr module
BorrowedReference clr_dict = Runtime.PyModule_GetDict(ImportHook.ClrModuleReference);
var locals = new PyDict();
try
{
BorrowedReference module = DefineModule("clr._extras");
BorrowedReference module_globals = Runtime.PyModule_GetDict(module);
Assembly assembly = Assembly.GetExecutingAssembly();
// add the contents of clr.py to the module
string clr_py = assembly.ReadStringResource("clr.py");
Exec(clr_py, module_globals, locals.Reference);
LoadSubmodule(module_globals, "clr.interop", "interop.py");
LoadMixins(module_globals);
// 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);
using (var keys = locals.Keys())
foreach (PyObject key in keys)
{
if (!key.ToString()!.StartsWith("_") || key.ToString()!.Equals("__version__"))
{
PyObject value = locals[key];
Runtime.PyDict_SetItem(clr_dict, key.Reference, value.Reference);
value.Dispose();
}
key.Dispose();
}
}
finally
{
locals.Dispose();
}
ImportHook.UpdateCLRModuleDict();
}
static BorrowedReference DefineModule(string name)
{
var module = Runtime.PyImport_AddModule(name);
var module_globals = Runtime.PyModule_GetDict(module);
var builtins = Runtime.PyEval_GetBuiltins();
Runtime.PyDict_SetItemString(module_globals, "__builtins__", builtins);
return module;
}
static void LoadSubmodule(BorrowedReference targetModuleDict, string fullName, string resourceName)
{
string? memberName = fullName.AfterLast('.');
Debug.Assert(memberName != null);
var module = DefineModule(fullName);
var module_globals = Runtime.PyModule_GetDict(module);
Assembly assembly = Assembly.GetExecutingAssembly();
string pyCode = assembly.ReadStringResource(resourceName);
Exec(pyCode, module_globals, module_globals);
Runtime.PyDict_SetItemString(targetModuleDict, memberName!, module);
}
static void LoadMixins(BorrowedReference targetModuleDict)
{
foreach (string nested in new[] { "collections" })
{
LoadSubmodule(targetModuleDict,
fullName: "clr._extras." + nested,
resourceName: typeof(PythonEngine).Namespace + ".Mixins." + nested + ".py");
}
}
static void OnDomainUnload(object _, EventArgs __)
{
Shutdown();
}
static void OnProcessExit(object _, EventArgs __)
{
Runtime.ProcessIsTerminating = true;
Shutdown();
}
///
/// 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.
///
[EditorBrowsable(EditorBrowsableState.Never)]
[Obsolete(Util.InternalUseOnly)]
public static IntPtr InitExt()
{
try
{
if (Runtime.IsInitialized)
{
var builtins = Runtime.PyEval_GetBuiltins();
var runtimeError = Runtime.PyDict_GetItemString(builtins, "RuntimeError");
Exceptions.SetError(runtimeError, "Python.NET runtime is already initialized");
return IntPtr.Zero;
}
Runtime.HostedInPython = true;
Initialize(setSysArgv: false);
Finalizer.Instance.ErrorHandler += AllowLeaksDuringShutdown;
}
catch (PythonException e)
{
e.Restore();
return IntPtr.Zero;
}
return Python.Runtime.ImportHook.GetCLRModule()
.DangerousMoveToPointerOrNull();
}
private static void AllowLeaksDuringShutdown(object sender, Finalizer.ErrorArgs e)
{
if (e.Error is RuntimeShutdownException)
{
e.Handled = true;
}
}
///
/// 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)
{
return;
}
// If the shutdown handlers trigger a domain unload,
// don't call shutdown again.
AppDomain.CurrentDomain.DomainUnload -= OnDomainUnload;
AppDomain.CurrentDomain.ProcessExit -= OnProcessExit;
ExecuteShutdownHandlers();
// Remember to shut down the runtime.
Runtime.Shutdown();
initialized = false;
InteropConfiguration = InteropConfiguration.MakeDefault();
}
///
/// Called when the engine is shut down.
///
/// Shutdown handlers are run in reverse order they were added, so that
/// resources available when running a shutdown handler are the same as
/// what was available when it was added.
///
public delegate void ShutdownHandler();
static List ShutdownHandlers = new List();
///
/// Add a function to be called when the engine is shut down.
///
/// Shutdown handlers are executed in the opposite order they were
/// added, so that you can be sure that everything that was initialized
/// when you added the handler is still initialized when you need to shut
/// down.
///
/// If the same shutdown handler is added several times, it will be run
/// several times.
///
/// Don't add shutdown handlers while running a shutdown handler.
///
public static void AddShutdownHandler(ShutdownHandler handler)
{
ShutdownHandlers.Add(handler);
}
///
/// Remove a shutdown handler.
///
/// If the same shutdown handler is added several times, only the last
/// one is removed.
///
/// Don't remove shutdown handlers while running a shutdown handler.
///
public static void RemoveShutdownHandler(ShutdownHandler handler)
{
for (int index = ShutdownHandlers.Count - 1; index >= 0; --index)
{
if (ShutdownHandlers[index] == handler)
{
ShutdownHandlers.RemoveAt(index);
break;
}
}
}
///
/// Run all the shutdown handlers.
///
/// They're run in opposite order they were added.
///
static void ExecuteShutdownHandlers()
{
while(ShutdownHandlers.Count > 0)
{
var handler = ShutdownHandlers[ShutdownHandlers.Count - 1];
ShutdownHandlers.RemoveAt(ShutdownHandlers.Count - 1);
handler();
}
}
///
/// 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.
///
internal static PyGILState 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.
///
internal static void ReleaseLock(PyGILState 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 unsafe IntPtr BeginAllowThreads()
{
return (IntPtr)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 unsafe void EndAllowThreads(IntPtr ts)
{
Runtime.PyEval_RestoreThread((PyThreadState*)ts);
}
public static PyObject Compile(string code, string filename = "", RunFlagType mode = RunFlagType.File)
{
var flag = (int)mode;
NewReference ptr = Runtime.Py_CompileString(code, filename, flag);
PythonException.ThrowIfIsNull(ptr);
return ptr.MoveToPyObject();
}
///
/// Eval Method
///
///
/// Evaluate a Python expression and returns the result.
/// It's a subset of Python eval function.
///
public static PyObject Eval(string code, PyDict? globals = null, PyObject? locals = null)
{
PyObject result = RunString(code, globals.BorrowNullable(), locals.BorrowNullable(), RunFlagType.Eval);
return result;
}
///
/// Exec Method
///
///
/// Run a string containing Python code.
/// It's a subset of Python exec function.
///
public static void Exec(string code, PyDict? globals = null, PyObject? locals = null)
{
using PyObject result = RunString(code, globals.BorrowNullable(), locals.BorrowNullable(), RunFlagType.File);
if (result.obj != Runtime.PyNone)
{
throw PythonException.ThrowLastAsClrException();
}
}
///
/// Exec Method
///
///
/// Run a string containing Python code.
/// It's a subset of Python exec function.
///
internal static void Exec(string code, BorrowedReference globals, BorrowedReference locals = default)
{
using PyObject result = RunString(code, globals: globals, locals: locals, RunFlagType.File);
if (result.obj != Runtime.PyNone)
{
throw PythonException.ThrowLastAsClrException();
}
}
///
/// Gets the Python thread ID.
///
/// The Python thread ID.
public static ulong GetPythonThreadID()
{
using PyObject threading = Py.Import("threading");
using PyObject id = threading.InvokeMethod("get_ident");
return id.As();
}
///
/// Interrupts the execution of a thread.
///
/// The Python thread ID.
/// The number of thread states modified; this is normally one, but will be zero if the thread id is not found.
public static int Interrupt(ulong pythonThreadID)
{
if (RuntimeInformation.IsOSPlatform(OSPlatform.Windows))
{
return Runtime.PyThreadState_SetAsyncExcLLP64((uint)pythonThreadID, Exceptions.KeyboardInterrupt);
}
return Runtime.PyThreadState_SetAsyncExcLP64(pythonThreadID, Exceptions.KeyboardInterrupt);
}
///
/// RunString Method. Function has been deprecated and will be removed.
/// Use Exec/Eval/RunSimpleString instead.
///
[Obsolete("RunString is deprecated and will be removed. Use Exec/Eval/RunSimpleString instead.")]
public static PyObject RunString(string code, PyDict? globals = null, PyObject? locals = null)
{
return RunString(code, globals.BorrowNullable(), locals.BorrowNullable(), RunFlagType.File);
}
///
/// Internal 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.
///
internal static PyObject RunString(string code, BorrowedReference globals, BorrowedReference locals, RunFlagType flag)
{
if (code is null) throw new ArgumentNullException(nameof(code));
NewReference tempGlobals = default;
if (globals.IsNull)
{
globals = Runtime.PyEval_GetGlobals();
if (globals.IsNull)
{
tempGlobals = Runtime.PyDict_New();
globals = tempGlobals.BorrowOrThrow();
Runtime.PyDict_SetItem(
globals, PyIdentifier.__builtins__,
Runtime.PyEval_GetBuiltins()
);
}
}
if (locals == null)
{
locals = globals;
}
try
{
NewReference result = Runtime.PyRun_String(
code, flag, globals, locals
);
PythonException.ThrowIfIsNull(result);
return result.MoveToPyObject();
}
finally
{
tempGlobals.Dispose();
}
}
}
public enum RunFlagType : int
{
Single = 256,
File = 257, /* Py_file_input */
Eval = 258
}
}