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authorthegeorg <[email protected]>2024-02-19 02:38:52 +0300
committerthegeorg <[email protected]>2024-02-19 02:50:43 +0300
commitd96fa07134c06472bfee6718b5cfd1679196fc99 (patch)
tree31ec344fa9d3ff8dc038692516b6438dfbdb8a2d /contrib/tools/python3/Include/internal/pycore_condvar.h
parent452cf9e068aef7110e35e654c5d47eb80111ef89 (diff)
Sync contrib/tools/python3 layout with upstream
* Move src/ subdir contents to the top of the layout * Rename self-written lib -> lib2 to avoid CaseFolding warning from the VCS * Regenerate contrib/libs/python proxy-headers accordingly 4ccc62ac1511abcf0fed14ccade38e984e088f1e
Diffstat (limited to 'contrib/tools/python3/Include/internal/pycore_condvar.h')
-rw-r--r--contrib/tools/python3/Include/internal/pycore_condvar.h99
1 files changed, 99 insertions, 0 deletions
diff --git a/contrib/tools/python3/Include/internal/pycore_condvar.h b/contrib/tools/python3/Include/internal/pycore_condvar.h
new file mode 100644
index 00000000000..acdc9db12c5
--- /dev/null
+++ b/contrib/tools/python3/Include/internal/pycore_condvar.h
@@ -0,0 +1,99 @@
+#ifndef Py_INTERNAL_CONDVAR_H
+#define Py_INTERNAL_CONDVAR_H
+
+#ifndef Py_BUILD_CORE
+# error "this header requires Py_BUILD_CORE define"
+#endif
+
+#ifndef _POSIX_THREADS
+/* This means pthreads are not implemented in libc headers, hence the macro
+ not present in unistd.h. But they still can be implemented as an external
+ library (e.g. gnu pth in pthread emulation) */
+# ifdef HAVE_PTHREAD_H
+# include <pthread.h> /* _POSIX_THREADS */
+# endif
+#endif
+
+#ifdef _POSIX_THREADS
+/*
+ * POSIX support
+ */
+#define Py_HAVE_CONDVAR
+
+#ifdef HAVE_PTHREAD_H
+# include <pthread.h>
+#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>
+
+/* options */
+/* non-emulated condition variables are provided for those that want
+ * to target Windows Vista. Modify this macro to enable them.
+ */
+#ifndef _PY_EMULATED_WIN_CV
+#define _PY_EMULATED_WIN_CV 1 /* use emulated condition variables */
+#endif
+
+/* fall back to emulation if not targeting 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 Win7 primitives if build target is Win7 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 */