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Diffstat (limited to '3rdParty/Boost/boost/thread/win32/once.hpp')
-rw-r--r--3rdParty/Boost/boost/thread/win32/once.hpp136
1 files changed, 136 insertions, 0 deletions
diff --git a/3rdParty/Boost/boost/thread/win32/once.hpp b/3rdParty/Boost/boost/thread/win32/once.hpp
new file mode 100644
index 0000000..a6fcc94
--- /dev/null
+++ b/3rdParty/Boost/boost/thread/win32/once.hpp
@@ -0,0 +1,136 @@
+#ifndef BOOST_THREAD_WIN32_ONCE_HPP
+#define BOOST_THREAD_WIN32_ONCE_HPP
+
+// once.hpp
+//
+// (C) Copyright 2005-7 Anthony Williams
+// (C) Copyright 2005 John Maddock
+//
+// Distributed under the Boost Software License, Version 1.0. (See
+// accompanying file LICENSE_1_0.txt or copy at
+// http://www.boost.org/LICENSE_1_0.txt)
+
+#include <cstring>
+#include <cstddef>
+#include <boost/assert.hpp>
+#include <boost/static_assert.hpp>
+#include <boost/detail/interlocked.hpp>
+#include <boost/thread/win32/thread_primitives.hpp>
+#include <boost/thread/win32/interlocked_read.hpp>
+
+#include <boost/config/abi_prefix.hpp>
+
+#ifdef BOOST_NO_STDC_NAMESPACE
+namespace std
+{
+ using ::memcpy;
+ using ::ptrdiff_t;
+}
+#endif
+
+namespace boost
+{
+ typedef long once_flag;
+
+#define BOOST_ONCE_INIT 0
+
+ namespace detail
+ {
+ struct win32_mutex_scoped_lock
+ {
+ void* const mutex_handle;
+ explicit win32_mutex_scoped_lock(void* mutex_handle_):
+ mutex_handle(mutex_handle_)
+ {
+ BOOST_VERIFY(!win32::WaitForSingleObject(mutex_handle,win32::infinite));
+ }
+ ~win32_mutex_scoped_lock()
+ {
+ BOOST_VERIFY(win32::ReleaseMutex(mutex_handle)!=0);
+ }
+ private:
+ void operator=(win32_mutex_scoped_lock&);
+ };
+
+#ifdef BOOST_NO_ANSI_APIS
+ template <class I>
+ void int_to_string(I p, wchar_t* buf)
+ {
+ for(unsigned i=0; i < sizeof(I)*2; ++i,++buf)
+ {
+ *buf = L'A' + static_cast<wchar_t>((p >> (i*4)) & 0x0f);
+ }
+ *buf = 0;
+ }
+#else
+ template <class I>
+ void int_to_string(I p, char* buf)
+ {
+ for(unsigned i=0; i < sizeof(I)*2; ++i,++buf)
+ {
+ *buf = 'A' + static_cast<char>((p >> (i*4)) & 0x0f);
+ }
+ *buf = 0;
+ }
+#endif
+
+ // create a named mutex. It doesn't really matter what this name is
+ // as long as it is unique both to this process, and to the address of "flag":
+ inline void* create_once_mutex(void* flag_address)
+ {
+
+#ifdef BOOST_NO_ANSI_APIS
+ typedef wchar_t char_type;
+ static const char_type fixed_mutex_name[]=L"{C15730E2-145C-4c5e-B005-3BC753F42475}-once-flag";
+#else
+ typedef char char_type;
+ static const char_type fixed_mutex_name[]="{C15730E2-145C-4c5e-B005-3BC753F42475}-once-flag";
+#endif
+ unsigned const once_mutex_name_fixed_buffer_size=sizeof(fixed_mutex_name)/sizeof(char_type);
+ unsigned const once_mutex_name_fixed_length=once_mutex_name_fixed_buffer_size-1;
+ unsigned const once_mutex_name_length=once_mutex_name_fixed_buffer_size+sizeof(void*)*2+sizeof(unsigned long)*2;
+ char_type mutex_name[once_mutex_name_length];
+
+ std::memcpy(mutex_name,fixed_mutex_name,sizeof(fixed_mutex_name));
+
+ BOOST_STATIC_ASSERT(sizeof(void*) == sizeof(std::ptrdiff_t));
+ detail::int_to_string(reinterpret_cast<std::ptrdiff_t>(flag_address), mutex_name + once_mutex_name_fixed_length);
+ detail::int_to_string(win32::GetCurrentProcessId(), mutex_name + once_mutex_name_fixed_length + sizeof(void*)*2);
+
+#ifdef BOOST_NO_ANSI_APIS
+ return win32::CreateMutexW(0, 0, mutex_name);
+#else
+ return win32::CreateMutexA(0, 0, mutex_name);
+#endif
+ }
+
+
+ }
+
+
+ template<typename Function>
+ void call_once(once_flag& flag,Function f)
+ {
+ // Try for a quick win: if the procedure has already been called
+ // just skip through:
+ long const function_complete_flag_value=0xc15730e2;
+
+ if(::boost::detail::interlocked_read_acquire(&flag)!=function_complete_flag_value)
+ {
+ void* const mutex_handle(::boost::detail::create_once_mutex(&flag));
+ BOOST_ASSERT(mutex_handle);
+ detail::win32::handle_manager const closer(mutex_handle);
+ detail::win32_mutex_scoped_lock const lock(mutex_handle);
+
+ if(flag!=function_complete_flag_value)
+ {
+ f();
+ BOOST_INTERLOCKED_EXCHANGE(&flag,function_complete_flag_value);
+ }
+ }
+ }
+}
+
+#include <boost/config/abi_suffix.hpp>
+
+#endif