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Diffstat (limited to 'ptw32_InterlockedCompareExchange.c')
-rw-r--r-- | ptw32_InterlockedCompareExchange.c | 108 |
1 files changed, 108 insertions, 0 deletions
diff --git a/ptw32_InterlockedCompareExchange.c b/ptw32_InterlockedCompareExchange.c new file mode 100644 index 0000000..0e0ccfd --- /dev/null +++ b/ptw32_InterlockedCompareExchange.c @@ -0,0 +1,108 @@ +/* + * ptw32_InterlockedCompareExchange.c + * + * Description: + * This translation unit implements routines which are private to + * the implementation and may be used throughout it. + * + * -------------------------------------------------------------------------- + * + * Pthreads-win32 - POSIX Threads Library for Win32 + * Copyright(C) 1998 John E. Bossom + * Copyright(C) 1999,2002 Pthreads-win32 contributors + * + * Contact Email: rpj@ise.canberra.edu.au + * + * The current list of contributors is contained + * in the file CONTRIBUTORS included with the source + * code distribution. The list can also be seen at the + * following World Wide Web location: + * http://sources.redhat.com/pthreads-win32/contributors.html + * + * This library is free software; you can redistribute it and/or + * modify it under the terms of the GNU Lesser General Public + * License as published by the Free Software Foundation; either + * version 2 of the License, or (at your option) any later version. + * + * This library 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 + * Lesser General Public License for more details. + * + * You should have received a copy of the GNU Lesser General Public + * License along with this library in the file COPYING.LIB; + * if not, write to the Free Software Foundation, Inc., + * 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA + */ + +#include "pthread.h" +#include "implement.h" + + +/* + * ptw32_InterlockedCompareExchange -- + * + * Needed because W95 doesn't support InterlockedCompareExchange. + * It is only used when running the dll on W95. Other versions of + * Windows use the Win32 supported version, which may be running on + * different processor types. + * + * This can't be inlined because we need to know it's address so that + * we can call it through a pointer. + */ +PTW32_INTERLOCKED_LONG WINAPI +ptw32_InterlockedCompareExchange(PTW32_INTERLOCKED_LPLONG location, + PTW32_INTERLOCKED_LONG value, + PTW32_INTERLOCKED_LONG comparand) +{ + PTW32_INTERLOCKED_LONG result; + +#if defined(_M_IX86) || defined(_X86_) + +#if defined(_MSC_VER) + + _asm { + PUSH ecx + PUSH edx + MOV ecx,dword ptr [location] + MOV edx,dword ptr [value] + MOV eax,dword ptr [comparand] + LOCK CMPXCHG dword ptr [ecx],edx ; if (EAX == [ECX]), + ; [ECX] = EDX + ; else + ; EAX = [ECX] + MOV dword ptr [result], eax + POP edx + POP ecx + } + +#elif defined(__GNUC__) + + __asm__ + ( + "lock\n\t" + "cmpxchgl %3,(%0)" /* if (EAX == [location]), */ + /* [location] = value */ + /* else */ + /* EAX = [location] */ + :"=r" (location), "=a" (result) + :"0" (location), "q" (value), "a" (comparand) + : "memory" ); + +#endif + +#else + + /* + * If execution gets to here then we should be running on a Win95 system + * but either running on something other than an X86 processor, or a + * compiler other than MSVC or GCC. Pthreads-win32 doesn't support that + * platform (yet). + */ + + result = 0; + +#endif + + return result; +} |