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using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;
using System.Reflection;
using System.Runtime.InteropServices;
namespace Python.Runtime
{
/// <summary>
/// This class provides the public interface of the Python runtime.
/// </summary>
public class PythonEngine : IDisposable
{
public static ShutdownMode ShutdownMode
{
get => Runtime.ShutdownMode;
set => Runtime.ShutdownMode = value;
}
public static ShutdownMode DefaultShutdownMode => Runtime.GetDefaultShutdownMode();
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;
public PythonEngine()
{
Initialize();
}
public PythonEngine(params string[] args)
{
Initialize(args);
}
public PythonEngine(IEnumerable<string> args)
{
Initialize(args);
}
public void Dispose()
{
Shutdown();
}
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
{
IntPtr p = Runtime.Py_GetProgramName();
return UcsMarshaler.PtrToPy3UnicodePy2String(p) ?? "";
}
set
{
Marshal.FreeHGlobal(_programName);
_programName = UcsMarshaler.Py3UnicodePy2StringtoPtr(value);
Runtime.Py_SetProgramName(_programName);
}
}
public static string PythonHome
{
get
{
IntPtr p = Runtime.Py_GetPythonHome();
return UcsMarshaler.PtrToPy3UnicodePy2String(p) ?? "";
}
set
{
// this value is null in the beginning
Marshal.FreeHGlobal(_pythonHome);
_pythonHome = UcsMarshaler.Py3UnicodePy2StringtoPtr(value);
Runtime.Py_SetPythonHome(_pythonHome);
}
}
public static string PythonPath
{
get
{
IntPtr p = Runtime.Py_GetPath();
return UcsMarshaler.PtrToPy3UnicodePy2String(p) ?? "";
}
set
{
Marshal.FreeHGlobal(_pythonPath);
_pythonPath = 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()); }
}
/// <summary>
/// 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
/// </summary>
public static void SetNoSiteFlag()
{
Runtime.SetNoSiteFlag();
}
public static int RunSimpleString(string code)
{
return Runtime.PyRun_SimpleString(code);
}
static bool libraryLoaded = false;
public static void InitializeLibrary(string library, string directory)
{
if (!libraryLoaded)
{
var _loader = Python.Runtime.Platform.LibraryLoader.Instance;
_loader.Load(library, directory);
libraryLoaded = true;
}
}
public static void Initialize()
{
Initialize(setSysArgv: true);
}
public static void Initialize(bool setSysArgv = true, bool initSigs = false, ShutdownMode mode = ShutdownMode.Default)
{
Initialize(Enumerable.Empty<string>(), setSysArgv: setSysArgv, initSigs: initSigs, mode);
}
/// <summary>
/// Initialize Method
/// </summary>
/// <remarks>
/// 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.
/// </remarks>
public static void Initialize(IEnumerable<string> args, bool setSysArgv = true, bool initSigs = false, ShutdownMode mode = ShutdownMode.Default)
{
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, mode);
initialized = true;
Exceptions.Clear();
// Make sure we clean up properly on app domain unload.
AppDomain.CurrentDomain.DomainUnload += OnDomainUnload;
// The global scope gets used implicitly quite early on, remember
// to clear it out when we shut down.
AddShutdownHandler(PyScopeManager.Global.Clear);
if (setSysArgv)
{
Py.SetArgv(args);
}
if (mode == ShutdownMode.Normal)
{
// TOOD: Check if this can be remove completely or not.
// 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";
//PythonEngine.Exec(code);
}
// Load the clr.py resource into the clr module
IntPtr clr = Python.Runtime.ImportHook.GetCLRModule();
IntPtr clr_dict = Runtime.PyModule_GetDict(clr);
var 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);
Assembly assembly = Assembly.GetExecutingAssembly();
using (Stream stream = assembly.GetManifestResourceStream("clr.py"))
using (var reader = new StreamReader(stream))
{
// add the contents of clr.py to the module
string clr_py = reader.ReadToEnd();
Exec(clr_py, module_globals, locals.Handle);
}
// 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.Handle, value.Handle);
value.Dispose();
}
key.Dispose();
}
}
finally
{
locals.Dispose();
}
}
static void OnDomainUnload(object _, EventArgs __)
{
Shutdown();
}
/// <summary>
/// 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.
/// </summary>
public static IntPtr InitExt()
{
try
{
Initialize(setSysArgv: false);
// 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";
PythonEngine.Exec(code);
}
catch (PythonException e)
{
e.Restore();
return IntPtr.Zero;
}
return Python.Runtime.ImportHook.GetCLRModule();
}
/// <summary>
/// Shutdown Method
/// </summary>
/// <remarks>
/// 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.
/// </remarks>
/// <param name="mode">The ShutdownMode to use when shutting down the Runtime</param>
public static void Shutdown(ShutdownMode mode)
{
if (!initialized)
{
return;
}
// If the shutdown handlers trigger a domain unload,
// don't call shutdown again.
AppDomain.CurrentDomain.DomainUnload -= OnDomainUnload;
PyScopeManager.Global.Clear();
ExecuteShutdownHandlers();
// Remember to shut down the runtime.
Runtime.Shutdown(mode);
PyObjectConversions.Reset();
initialized = false;
}
/// <summary>
/// Shutdown Method
/// </summary>
/// <remarks>
/// 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.
/// </remarks>
public static void Shutdown()
{
Shutdown(Runtime.ShutdownMode);
}
/// <summary>
/// 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.
/// </summary>
public delegate void ShutdownHandler();
static List<ShutdownHandler> ShutdownHandlers = new List<ShutdownHandler>();
/// <summary>
/// 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.
/// </summary>
public static void AddShutdownHandler(ShutdownHandler handler)
{
ShutdownHandlers.Add(handler);
}
/// <summary>
/// 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.
/// </summary>
public static void RemoveShutdownHandler(ShutdownHandler handler)
{
for (int index = ShutdownHandlers.Count - 1; index >= 0; --index)
{
if (ShutdownHandlers[index] == handler)
{
ShutdownHandlers.RemoveAt(index);
break;
}
}
}
/// <summary>
/// Run all the shutdown handlers.
///
/// They're run in opposite order they were added.
/// </summary>
static void ExecuteShutdownHandlers()
{
while(ShutdownHandlers.Count > 0)
{
var handler = ShutdownHandlers[ShutdownHandlers.Count - 1];
ShutdownHandlers.RemoveAt(ShutdownHandlers.Count - 1);
handler();
}
}
/// <summary>
/// AcquireLock Method
/// </summary>
/// <remarks>
/// 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.
/// </remarks>
public static IntPtr AcquireLock()
{
return Runtime.PyGILState_Ensure();
}
/// <summary>
/// ReleaseLock Method
/// </summary>
/// <remarks>
/// 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.
/// </remarks>
public static void ReleaseLock(IntPtr gs)
{
Runtime.PyGILState_Release(gs);
}
/// <summary>
/// BeginAllowThreads Method
/// </summary>
/// <remarks>
/// 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.
/// </remarks>
public static IntPtr BeginAllowThreads()
{
return Runtime.PyEval_SaveThread();
}
/// <summary>
/// EndAllowThreads Method
/// </summary>
/// <remarks>
/// 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.
/// </remarks>
public static void EndAllowThreads(IntPtr ts)
{
Runtime.PyEval_RestoreThread(ts);
}
/// <summary>
/// ImportModule Method
/// </summary>
/// <remarks>
/// 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.
/// </remarks>
public static PyObject ImportModule(string name)
{
IntPtr op = Runtime.PyImport_ImportModule(name);
PythonException.ThrowIfIsNull(op);
return new PyObject(op);
}
/// <summary>
/// ReloadModule Method
/// </summary>
/// <remarks>
/// Given a PyObject representing a previously loaded module, reload
/// the module.
/// </remarks>
public static PyObject ReloadModule(PyObject module)
{
IntPtr op = Runtime.PyImport_ReloadModule(module.Handle);
PythonException.ThrowIfIsNull(op);
return new PyObject(op);
}
/// <summary>
/// ModuleFromString Method
/// </summary>
/// <remarks>
/// Given a string module name and a string containing Python code,
/// execute the code in and return a module of the given name.
/// </remarks>
public static PyObject ModuleFromString(string name, string code)
{
IntPtr c = Runtime.Py_CompileString(code, "none", (int)RunFlagType.File);
PythonException.ThrowIfIsNull(c);
IntPtr m = Runtime.PyImport_ExecCodeModule(name, c);
PythonException.ThrowIfIsNull(m);
return new PyObject(m);
}
public static PyObject Compile(string code, string filename = "", RunFlagType mode = RunFlagType.File)
{
var flag = (int)mode;
IntPtr ptr = Runtime.Py_CompileString(code, filename, flag);
PythonException.ThrowIfIsNull(ptr);
return new PyObject(ptr);
}
/// <summary>
/// Eval Method
/// </summary>
/// <remarks>
/// Evaluate a Python expression and returns the result.
/// It's a subset of Python eval function.
/// </remarks>
public static PyObject Eval(string code, IntPtr? globals = null, IntPtr? locals = null)
{
PyObject result = RunString(code, globals, locals, RunFlagType.Eval);
return result;
}
/// <summary>
/// Exec Method
/// </summary>
/// <remarks>
/// Run a string containing Python code.
/// It's a subset of Python exec function.
/// </remarks>
public static void Exec(string code, IntPtr? globals = null, IntPtr? locals = null)
{
using (PyObject result = RunString(code, globals, locals, RunFlagType.File))
{
if (result.obj != Runtime.PyNone)
{
throw new PythonException();
}
}
}
/// <summary>
/// Gets the Python thread ID.
/// </summary>
/// <returns>The Python thread ID.</returns>
public static ulong GetPythonThreadID()
{
dynamic threading = Py.Import("threading");
return threading.InvokeMethod("get_ident");
}
/// <summary>
/// Interrupts the execution of a thread.
/// </summary>
/// <param name="pythonThreadID">The Python thread ID.</param>
/// <returns>The number of thread states modified; this is normally one, but will be zero if the thread id isn’t found.</returns>
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);
}
/// <summary>
/// RunString Method. Function has been deprecated and will be removed.
/// Use Exec/Eval/RunSimpleString instead.
/// </summary>
[Obsolete("RunString is deprecated and will be removed. Use Exec/Eval/RunSimpleString instead.")]
public static PyObject RunString(string code, IntPtr? globals = null, IntPtr? locals = null)
{
return RunString(code, globals, locals, RunFlagType.File);
}
/// <summary>
/// Internal RunString Method.
/// </summary>
/// <remarks>
/// 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.
/// </remarks>
internal static PyObject RunString(string code, IntPtr? globals, IntPtr? locals, RunFlagType flag)
{
var borrowedGlobals = true;
if (globals == null)
{
globals = Runtime.PyEval_GetGlobals();
if (globals == IntPtr.Zero)
{
globals = Runtime.PyDict_New();
Runtime.PyDict_SetItem(
globals.Value, PyIdentifier.__builtins__,
Runtime.PyEval_GetBuiltins()
);
borrowedGlobals = false;
}
}
if (locals == null)
{
locals = globals;
}
try
{
NewReference result = Runtime.PyRun_String(
code, flag, globals.Value, locals.Value
);
PythonException.ThrowIfIsNull(result);
return result.MoveToPyObject();
}
finally
{
if (!borrowedGlobals)
{
Runtime.XDecref(globals.Value);
}
}
}
}
public enum RunFlagType : int
{
Single = 256,
File = 257, /* Py_file_input */
Eval = 258
}
public static class Py
{
public static GILState GIL()
{
if (!PythonEngine.IsInitialized)
{
PythonEngine.Initialize();
}
return new GILState();
}
public static PyScope CreateScope()
{
var scope = PyScopeManager.Global.Create();
return scope;
}
public static PyScope CreateScope(string name)
{
var scope = PyScopeManager.Global.Create(name);
return scope;
}
public class GILState : IDisposable
{
private readonly IntPtr state;
private bool isDisposed;
internal GILState()
{
state = PythonEngine.AcquireLock();
}
public void Dispose()
{
if (this.isDisposed) return;
PythonEngine.ReleaseLock(state);
GC.SuppressFinalize(this);
this.isDisposed = true;
}
~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 (var 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.XDecref(value);
}
}
return dict;
}
public static PyObject Import(string name)
{
return PythonEngine.ImportModule(name);
}
public static void SetArgv()
{
IEnumerable<string> args;
try
{
args = Environment.GetCommandLineArgs();
}
catch (NotSupportedException)
{
args = Enumerable.Empty<string>();
}
SetArgv(
new[] { "" }.Concat(
Environment.GetCommandLineArgs().Skip(1)
)
);
}
public static void SetArgv(params string[] argv)
{
SetArgv(argv as IEnumerable<string>);
}
public static void SetArgv(IEnumerable<string> argv)
{
using (GIL())
{
string[] arr = argv.ToArray();
Runtime.PySys_SetArgvEx(arr.Length, arr, 0);
Runtime.CheckExceptionOccurred();
}
}
public static void With(PyObject obj, Action<dynamic> Body)
{
// Behavior described here:
// https://docs.python.org/2/reference/datamodel.html#with-statement-context-managers
IntPtr type = Runtime.PyNone;
IntPtr val = Runtime.PyNone;
IntPtr traceBack = Runtime.PyNone;
PythonException ex = null;
try
{
PyObject enterResult = obj.InvokeMethod("__enter__");
Body(enterResult);
}
catch (PythonException e)
{
ex = e;
type = ex.PyType.Coalesce(type);
val = ex.PyValue.Coalesce(val);
traceBack = ex.PyTB.Coalesce(traceBack);
}
Runtime.XIncref(type);
Runtime.XIncref(val);
Runtime.XIncref(traceBack);
var exitResult = obj.InvokeMethod("__exit__", new PyObject(type), new PyObject(val), new PyObject(traceBack));
if (ex != null && !exitResult.IsTrue()) throw ex;
}
}
}