python 2.7 -> python 3.14

extern/include/python/internal/pycore_condvar.h

@@ -0,0 +1,93 @@
+#ifndef Py_INTERNAL_CONDVAR_H
+#define Py_INTERNAL_CONDVAR_H
+
+#ifndef Py_BUILD_CORE
+#  error "this header requires Py_BUILD_CORE define"
+#endif
+
+#include "pycore_pythread.h"      // _POSIX_THREADS
+
+
+#ifdef _POSIX_THREADS
+/*
+ * POSIX support
+ */
+#define Py_HAVE_CONDVAR
+
+#ifdef HAVE_PTHREAD_H
+#  include <pthread.h>            // pthread_mutex_t
+#endif
+
+#define PyMUTEX_T pthread_mutex_t
+#define PyCOND_T pthread_cond_t
+
+#elif defined(NT_THREADS)
+/*
+ * Windows (XP, 2003 server and later, as well as (hopefully) CE) support
+ *
+ * Emulated condition variables ones that work with XP and later, plus
+ * example native support on VISTA and onwards.
+ */
+#define Py_HAVE_CONDVAR
+
+/* include windows if it hasn't been done before */
+#ifndef WIN32_LEAN_AND_MEAN
+#  define WIN32_LEAN_AND_MEAN
+#endif
+#include <windows.h>              // CRITICAL_SECTION
+
+/* options */
+/* emulated condition variables are provided for those that want
+ * to target Windows XP or earlier. Modify this macro to enable them.
+ */
+#ifndef _PY_EMULATED_WIN_CV
+#define _PY_EMULATED_WIN_CV 0  /* use non-emulated condition variables */
+#endif
+
+/* fall back to emulation if targeting earlier than Vista */
+#if !defined NTDDI_VISTA || NTDDI_VERSION < NTDDI_VISTA
+#undef _PY_EMULATED_WIN_CV
+#define _PY_EMULATED_WIN_CV 1
+#endif
+
+#if _PY_EMULATED_WIN_CV
+
+typedef CRITICAL_SECTION PyMUTEX_T;
+
+/* The ConditionVariable object.  From XP onwards it is easily emulated
+   with a Semaphore.
+   Semaphores are available on Windows XP (2003 server) and later.
+   We use a Semaphore rather than an auto-reset event, because although
+   an auto-reset event might appear to solve the lost-wakeup bug (race
+   condition between releasing the outer lock and waiting) because it
+   maintains state even though a wait hasn't happened, there is still
+   a lost wakeup problem if more than one thread are interrupted in the
+   critical place.  A semaphore solves that, because its state is
+   counted, not Boolean.
+   Because it is ok to signal a condition variable with no one
+   waiting, we need to keep track of the number of
+   waiting threads.  Otherwise, the semaphore's state could rise
+   without bound.  This also helps reduce the number of "spurious wakeups"
+   that would otherwise happen.
+ */
+
+typedef struct _PyCOND_T
+{
+    HANDLE sem;
+    int waiting; /* to allow PyCOND_SIGNAL to be a no-op */
+} PyCOND_T;
+
+#else /* !_PY_EMULATED_WIN_CV */
+
+/* Use native Windows primitives if build target is Vista or higher */
+
+/* SRWLOCK is faster and better than CriticalSection */
+typedef SRWLOCK PyMUTEX_T;
+
+typedef CONDITION_VARIABLE  PyCOND_T;
+
+#endif /* _PY_EMULATED_WIN_CV */
+
+#endif /* _POSIX_THREADS, NT_THREADS */
+
+#endif /* Py_INTERNAL_CONDVAR_H */