--- /dev/null
+/* Implementation of W32-specific threads compatibility routines for
+ libgcc2. */
+
+/* Copyright (C) 1999, 2000, 2002, 2004, 2008, 2009 Free Software Foundation, Inc.
+ Contributed by Mumit Khan <khan@xraylith.wisc.edu>.
+ Modified and moved to separate file by Danny Smith
+ <dannysmith@users.sourceforge.net>.
+
+This file is part of GCC.
+
+GCC is free software; you can redistribute it and/or modify it under
+the terms of the GNU General Public License as published by the Free
+Software Foundation; either version 3, or (at your option) any later
+version.
+
+GCC is distributed in the hope that it will be useful, but WITHOUT ANY
+WARRANTY; without even the implied warranty of MERCHANTABILITY or
+FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
+for more details.
+
+Under Section 7 of GPL version 3, you are granted additional
+permissions described in the GCC Runtime Library Exception, version
+3.1, as published by the Free Software Foundation.
+
+You should have received a copy of the GNU General Public License and
+a copy of the GCC Runtime Library Exception along with this program;
+see the files COPYING3 and COPYING.RUNTIME respectively. If not, see
+<http://www.gnu.org/licenses/>. */
+
+#include <windows.h>
+#ifndef __GTHREAD_HIDE_WIN32API
+# define __GTHREAD_HIDE_WIN32API 1
+#endif
+#undef __GTHREAD_I486_INLINE_LOCK_PRIMITIVES
+#define __GTHREAD_I486_INLINE_LOCK_PRIMITIVES
+#include <gthr-win32.h>
+
+/* Windows32 threads specific definitions. The windows32 threading model
+ does not map well into pthread-inspired gcc's threading model, and so
+ there are caveats one needs to be aware of.
+
+ 1. The destructor supplied to __gthread_key_create is ignored for
+ generic x86-win32 ports. This will certainly cause memory leaks
+ due to unreclaimed eh contexts (sizeof (eh_context) is at least
+ 24 bytes for x86 currently).
+
+ This memory leak may be significant for long-running applications
+ that make heavy use of C++ EH.
+
+ However, Mingw runtime (version 0.3 or newer) provides a mechanism
+ to emulate pthreads key dtors; the runtime provides a special DLL,
+ linked in if -mthreads option is specified, that runs the dtors in
+ the reverse order of registration when each thread exits. If
+ -mthreads option is not given, a stub is linked in instead of the
+ DLL, which results in memory leak. Other x86-win32 ports can use
+ the same technique of course to avoid the leak.
+
+ 2. The error codes returned are non-POSIX like, and cast into ints.
+ This may cause incorrect error return due to truncation values on
+ hw where sizeof (DWORD) > sizeof (int).
+
+ 3. We are currently using a special mutex instead of the Critical
+ Sections, since Win9x does not support TryEnterCriticalSection
+ (while NT does).
+
+ The basic framework should work well enough. In the long term, GCC
+ needs to use Structured Exception Handling on Windows32. */
+
+int
+__gthr_win32_once (__gthread_once_t *once, void (*func) (void))
+{
+ if (once == NULL || func == NULL)
+ return EINVAL;
+
+ if (! once->done)
+ {
+ if (InterlockedIncrement (&(once->started)) == 0)
+ {
+ (*func) ();
+ once->done = TRUE;
+ }
+ else
+ {
+ /* Another thread is currently executing the code, so wait for it
+ to finish; yield the CPU in the meantime. If performance
+ does become an issue, the solution is to use an Event that
+ we wait on here (and set above), but that implies a place to
+ create the event before this routine is called. */
+ while (! once->done)
+ Sleep (0);
+ }
+ }
+ return 0;
+}
+
+/* Windows32 thread local keys don't support destructors; this leads to
+ leaks, especially in threaded applications making extensive use of
+ C++ EH. Mingw uses a thread-support DLL to work-around this problem. */
+
+int
+__gthr_win32_key_create (__gthread_key_t *key,
+ void (*dtor) (void *) __attribute__((unused)))
+{
+ int status = 0;
+ DWORD tls_index = TlsAlloc ();
+ if (tls_index != 0xFFFFFFFF)
+ {
+ *key = tls_index;
+#ifdef MINGW32_SUPPORTS_MT_EH
+ /* Mingw runtime will run the dtors in reverse order for each thread
+ when the thread exits. */
+ status = __mingwthr_key_dtor (*key, dtor);
+#endif
+ }
+ else
+ status = (int) GetLastError ();
+ return status;
+}
+
+int
+__gthr_win32_key_delete (__gthread_key_t key)
+{
+ return (TlsFree (key) != 0) ? 0 : (int) GetLastError ();
+}
+
+void *
+__gthr_win32_getspecific (__gthread_key_t key)
+{
+ DWORD lasterror;
+ void *ptr;
+ lasterror = GetLastError();
+ ptr = TlsGetValue(key);
+ SetLastError( lasterror );
+ return ptr;
+}
+
+int
+__gthr_win32_setspecific (__gthread_key_t key, const void *ptr)
+{
+ if (TlsSetValue (key, CONST_CAST2(void *, const void *, ptr)) != 0)
+ return 0;
+ else
+ return GetLastError ();
+}
+
+void
+__gthr_win32_mutex_init_function (__gthread_mutex_t *mutex)
+{
+ mutex->counter = -1;
+ mutex->sema = CreateSemaphore (NULL, 0, 65535, NULL);
+}
+
+void
+__gthr_win32_mutex_destroy (__gthread_mutex_t *mutex)
+{
+ CloseHandle ((HANDLE) mutex->sema);
+}
+
+int
+__gthr_win32_mutex_lock (__gthread_mutex_t *mutex)
+{
+ if (InterlockedIncrement (&mutex->counter) == 0 ||
+ WaitForSingleObject (mutex->sema, INFINITE) == WAIT_OBJECT_0)
+ return 0;
+ else
+ {
+ /* WaitForSingleObject returns WAIT_FAILED, and we can only do
+ some best-effort cleanup here. */
+ InterlockedDecrement (&mutex->counter);
+ return 1;
+ }
+}
+
+int
+__gthr_win32_mutex_trylock (__gthread_mutex_t *mutex)
+{
+ if (__GTHR_W32_InterlockedCompareExchange (&mutex->counter, 0, -1) < 0)
+ return 0;
+ else
+ return 1;
+}
+
+int
+__gthr_win32_mutex_unlock (__gthread_mutex_t *mutex)
+{
+ if (InterlockedDecrement (&mutex->counter) >= 0)
+ return ReleaseSemaphore (mutex->sema, 1, NULL) ? 0 : 1;
+ else
+ return 0;
+}
+
+void
+__gthr_win32_recursive_mutex_init_function (__gthread_recursive_mutex_t *mutex)
+{
+ mutex->counter = -1;
+ mutex->depth = 0;
+ mutex->owner = 0;
+ mutex->sema = CreateSemaphore (NULL, 0, 65535, NULL);
+}
+
+int
+__gthr_win32_recursive_mutex_lock (__gthread_recursive_mutex_t *mutex)
+{
+ DWORD me = GetCurrentThreadId();
+ if (InterlockedIncrement (&mutex->counter) == 0)
+ {
+ mutex->depth = 1;
+ mutex->owner = me;
+ }
+ else if (mutex->owner == me)
+ {
+ InterlockedDecrement (&mutex->counter);
+ ++(mutex->depth);
+ }
+ else if (WaitForSingleObject (mutex->sema, INFINITE) == WAIT_OBJECT_0)
+ {
+ mutex->depth = 1;
+ mutex->owner = me;
+ }
+ else
+ {
+ /* WaitForSingleObject returns WAIT_FAILED, and we can only do
+ some best-effort cleanup here. */
+ InterlockedDecrement (&mutex->counter);
+ return 1;
+ }
+ return 0;
+}
+
+int
+__gthr_win32_recursive_mutex_trylock (__gthread_recursive_mutex_t *mutex)
+{
+ DWORD me = GetCurrentThreadId();
+ if (__GTHR_W32_InterlockedCompareExchange (&mutex->counter, 0, -1) < 0)
+ {
+ mutex->depth = 1;
+ mutex->owner = me;
+ }
+ else if (mutex->owner == me)
+ ++(mutex->depth);
+ else
+ return 1;
+
+ return 0;
+}
+
+int
+__gthr_win32_recursive_mutex_unlock (__gthread_recursive_mutex_t *mutex)
+{
+ --(mutex->depth);
+ if (mutex->depth == 0)
+ {
+ mutex->owner = 0;
+
+ if (InterlockedDecrement (&mutex->counter) >= 0)
+ return ReleaseSemaphore (mutex->sema, 1, NULL) ? 0 : 1;
+ }
+
+ return 0;
+}
projects / msp430-gcc.git / blobdiff