From 6df25e8004949862435b2a55388f146ca08f6828 Mon Sep 17 00:00:00 2001
From: Rein Klazes <rklazes@casema.net>
Date: Sat, 14 Nov 1998 18:21:32 +0000
Subject: [PATCH] Added implementations for InterlockedExchangeAdd() and
 InterlockedCompareExchange().

---
 relay32/kernel32.spec |  4 +--
 win32/thread.c        | 71 ++++++++++++++++++++++++++++++++++++++++++-
 2 files changed, 72 insertions(+), 3 deletions(-)

diff --git a/relay32/kernel32.spec b/relay32/kernel32.spec
index 279ea6368d8..3b81fd2cf5b 100644
--- a/relay32/kernel32.spec
+++ b/relay32/kernel32.spec
@@ -893,8 +893,8 @@ init	MAIN_KernelInit
 875 stdcall GetFileAttributesExW(wstr long ptr) GetFileAttributesEx32W
 876 stub GetProcessPriorityBoost
 877 stub GetThreadPriorityBoost
-878 stub InterlockedCompareExchange
-879 stub InterlockedExchangeAdd
+878 stdcall InterlockedCompareExchange (ptr long long) InterlockedCompareExchange
+879 stdcall InterlockedExchangeAdd (ptr long ) InterlockedExchangeAdd
 880 stdcall IsProcessorFeaturePresent(long) IsProcessorFeaturePresent
 881 stub OpenWaitableTimerA
 882 stub OpenWaitableTimerW
diff --git a/win32/thread.c b/win32/thread.c
index cdf46ab7679..a235a5f2f6f 100644
--- a/win32/thread.c
+++ b/win32/thread.c
@@ -7,7 +7,7 @@
 
 #include <unistd.h>
 #include <string.h>
-#include "windows.h"
+#include "winnt.h"
 #include "winbase.h"
 #include "winerror.h"
 #include "debug.h"
@@ -131,3 +131,72 @@ LONG WINAPI InterlockedExchange(
 	return ret;
 #endif	
 }
+
+/************************************************************************
+ *           InterlockedCompareExchange		[KERNEL32.879]
+ *
+ * Atomically compares Destination and Comperand, and if found equal exchanges
+ * the value of Destination with Exchange
+ *
+ * RETURNS
+ *	Prior value of value pointed to by Destination
+ */
+PVOID WINAPI InterlockedCompareExchange(
+	    PVOID *Destination, /* Address of 32-bit value to exchange */
+	    PVOID Exchange,      /* change value, 32 bits */ 
+            PVOID Comperand      /* value to compare, 32 bits */
+) {
+#if defined(__i386__)&&defined(__GNUC__)	
+	PVOID ret;
+	__asm__ ( /* lock for SMP systems */
+                  "lock\n\t"
+                  "cmpxchgl %2,(%1)"
+                  :"=r" (ret)
+                  :"r" (Destination),"r" (Exchange), "0" (Comperand)
+                  :"memory" );
+	return ret;
+#else
+	PVOID ret;
+	/* StopAllThreadsAndProcesses() */	
+
+	ret=*Destination;
+        if(*Destination==Comperand) *Destination=Exchange;
+
+	/* ResumeAllThreadsAndProcesses() */
+	return ret;
+#endif	
+}
+
+/************************************************************************
+ *           InterlockedExchangeAdd			[KERNEL32.880]
+ *
+ * Atomically adds Increment to Addend and returns the previous value of
+ * Addend
+ *
+ * RETURNS
+ *	Prior value of value pointed to by cwAddendTarget
+ */
+LONG WINAPI InterlockedExchangeAdd(
+	    PLONG Addend, /* Address of 32-bit value to exchange */
+	    LONG Increment /* Value to add */
+) {
+#if defined(__i386__)&&defined(__GNUC__)	
+	LONG ret;
+	__asm__ ( /* lock for SMP systems */
+                  "lock\n\t"
+                  "xaddl %0,(%1)"
+                  :"=r" (ret)
+                  :"r" (Addend), "0" (Increment)
+                  :"memory" );
+	return ret;
+#else
+	LONG ret;
+	/* StopAllThreadsAndProcesses() */	
+
+	ret = *Addend;
+	*Addend += Increment;
+
+	/* ResumeAllThreadsAndProcesses() */
+	return ret;
+#endif	
+}