added some threading related functions

Massimiliano Pippi · sbinet · commit 894982222676 · 2016-04-01T17:08:29.000+02:00
diff --git a/python.go b/python.go
@@ -8,6 +8,14 @@ import (
 	"fmt"
 )
 
+// PyGILState is the Go alias for the PyGILState_STATE enum
+type PyGILState C.PyGILState_STATE
+
+// PyThreadState layer
+type PyThreadState struct {
+	ptr *C.PyThreadState
+}
+
 // Initialize initializes the python interpreter and its GIL
 func Initialize() error {
 	// make sure the python interpreter has been initialized
@@ -35,4 +43,62 @@ func Finalize() error {
 	return nil
 }
 
+// PyThreadState* PyEval_SaveThread()
+// Release the global interpreter lock (if it has been created and thread
+// support is enabled) and reset the thread state to NULL, returning the
+// previous thread state (which is not NULL). If the lock has been created,
+// the current thread must have acquired it. (This function is available even
+// when thread support is disabled at compile time.)
+func PyEval_SaveThread() *PyThreadState {
+	state := C.PyEval_SaveThread()
+	return &PyThreadState{ptr: state}
+}
+
+// void PyEval_RestoreThread(PyThreadState *tstate)
+// Acquire the global interpreter lock (if it has been created and thread
+// support is enabled) and set the thread state to tstate, which must not be
+// NULL. If the lock has been created, the current thread must not have
+// acquired it, otherwise deadlock ensues. (This function is available even
+// when thread support is disabled at compile time.)
+func PyEval_RestoreThread(state *PyThreadState) {
+	C.PyEval_RestoreThread(state.ptr)
+}
+
+// Ensure that the current thread is ready to call the Python C API regardless
+// of the current state of Python, or of the global interpreter lock. This may
+// be called as many times as desired by a thread as long as each call is
+// matched with a call to PyGILState_Release(). In general, other thread-related
+// APIs may be used between PyGILState_Ensure() and PyGILState_Release() calls
+// as long as the thread state is restored to its previous state before the
+// Release(). For example, normal usage of the Py_BEGIN_ALLOW_THREADS and
+// Py_END_ALLOW_THREADS macros is acceptable.
+//
+// The return value is an opaque “handle” to the thread state when
+// PyGILState_Ensure() was called, and must be passed to PyGILState_Release()
+// to ensure Python is left in the same state. Even though recursive calls are
+// allowed, these handles cannot be shared - each unique call to
+// PyGILState_Ensure() must save the handle for its call to PyGILState_Release().
+//
+// When the function returns, the current thread will hold the GIL and be able
+// to call arbitrary Python code. Failure is a fatal error.
+//
+// New in version 2.3.
+func PyGILState_Ensure() PyGILState {
+	return PyGILState(C.PyGILState_Ensure())
+}
+
+// void PyGILState_Release(PyGILState_STATE)
+// Release any resources previously acquired. After this call, Python’s state
+// will be the same as it was prior to the corresponding PyGILState_Ensure()
+// call (but generally this state will be unknown to the caller, hence the use
+// of the GILState API).
+//
+// Every call to PyGILState_Ensure() must be matched by a call to
+// PyGILState_Release() on the same thread.
+//
+// New in version 2.3.
+func PyGILState_Release(state PyGILState) {
+	C.PyGILState_Release(C.PyGILState_STATE(state))
+}
+
 // EOF
