--- a/src/atomic/linux/SDL_atomic.c	Wed Jun 24 20:04:08 2009 +0000
+++ b/src/atomic/linux/SDL_atomic.c	Wed Jun 24 20:20:57 2009 +0000
@@ -29,148 +29,147 @@
 Uint32
 SDL_AtomicExchange32(Uint32 * ptr, Uint32 value)
 {
-   return 0;
+   return __sync_lock_test_and_set(ptr, value);
 }
 
 SDL_bool
 SDL_AtomicCompareThenSet32(Uint32 * ptr, Uint32 oldvalue, Uint32 newvalue)
 {
-   return SDL_false;
+   return (SDL_bool)__sync_bool_compare_and_swap(ptr, oldvalue, newvalue);
 }
 
 SDL_bool
 SDL_AtomicTestThenSet32(Uint32 * ptr)
 {
-   return SDL_false;
+   return (SDL_bool)(0 == __sync_lock_test_and_set(ptr, 1));
 }
 
 void
 SDL_AtomicClear32(Uint32 * ptr)
 {
+   __sync_lock_release(ptr);
 }
 
 Uint32
 SDL_AtomicFetchThenIncrement32(Uint32 * ptr)
 {
-   return 0;
+   return __sync_fetch_and_add(ptr, 1);
 }
 
 Uint32
 SDL_AtomicFetchThenDecrement32(Uint32 * ptr)
 {
-   return 0;
+   return __sync_fetch_and_sub(ptr, 1);
 }
 
 Uint32
 SDL_AtomicFetchThenAdd32(Uint32 * ptr, Uint32 value)
 {
-   return 0;
+   return __sync_fetch_and_add(ptr, value);
 }
 
 Uint32
 SDL_AtomicFetchThenSubtract32(Uint32 * ptr, Uint32 value)
 {
-   return 0;
+   return __sync_fetch_and_sub(ptr, value);
 }
 
 Uint32
 SDL_AtomicIncrementThenFetch32(Uint32 * ptr)
 {
-   return 0;
+   return __sync_add_and_fetch(ptr, 1);
 }
 
 Uint32
 SDL_AtomicDecrementThenFetch32(Uint32 * ptr)
 {
-   return 0;
+   return __sync_sub_and_fetch(ptr, 1);
 }
 
 Uint32
 SDL_AtomicAddThenFetch32(Uint32 * ptr, Uint32 value)
 {
-   return 0;
+   return __sync_add_and_fetch(ptr, value);
 }
 
 Uint32
 SDL_AtomicSubtractThenFetch32(Uint32 * ptr, Uint32 value)
 {
-   return 0;
+   return __sync_sub_and_fetch(ptr, value);
 }
 
-
 #ifdef SDL_HAS_64BIT_TYPE
 
 Uint64
 SDL_AtomicExchange64(Uint64 * ptr, Uint64 value)
 {
-   return 0;
+   return __sync_lock_test_and_set(ptr, value);
 }
 
 SDL_bool
-SDL_AtomicCompareThenSet64(Uint64 * ptr,
-Uint64 oldvalue, Uint64 newvalue)
+SDL_AtomicCompareThenSet64(Uint64 * ptr, Uint64 oldvalue, Uint64 newvalue)
 {
-   return SDL_false;
+   return (SDL_bool)__sync_bool_compare_and_swap(ptr, oldvalue, newvalue);
 }
 
 SDL_bool
 SDL_AtomicTestThenSet64(Uint64 * ptr)
 {
-   return SDL_false;
+   return (SDL_bool)(0 == __sync_lock_test_and_set(ptr, 1));
 }
 
 void
 SDL_AtomicClear64(Uint64 * ptr)
 {
+   __sync_lock_release(ptr);
 }
 
 Uint64
 SDL_AtomicFetchThenIncrement64(Uint64 * ptr)
 {
-   return 0;
+   return __sync_fetch_and_add(ptr, 1);
 }
 
 Uint64
 SDL_AtomicFetchThenDecrement64(Uint64 * ptr)
 {
-   return 0;
+   return __sync_fetch_and_sub(ptr, 1);
 }
 
 Uint64
 SDL_AtomicFetchThenAdd64(Uint64 * ptr, Uint64 value)
 {
-   return 0;
+   return __sync_fetch_and_add(ptr, value);
 }
 
 Uint64
 SDL_AtomicFetchThenSubtract64(Uint64 * ptr, Uint64 value)
 {
-   return 0;
+   return __sync_fetch_and_sub(ptr, value);
 }
 
 Uint64
 SDL_AtomicIncrementThenFetch64(Uint64 * ptr)
 {
-   return 0;
+   return __sync_add_and_fetch(ptr, 1);
 }
 
 Uint64
 SDL_AtomicDecrementThenFetch64(Uint64 * ptr)
 {
-   return 0;
+   return __sync_sub_and_fetch(ptr, 1);
 }
 
 Uint64
 SDL_AtomicAddThenFetch64(Uint64 * ptr, Uint64 value)
 {
-   return 0;
+   return __sync_add_and_fetch(ptr, value);
 }
 
 Uint64
 SDL_AtomicSubtractThenFetch64(Uint64 * ptr, Uint64 value)
 {
-   return 0;
+   return __sync_sub_and_fetch(ptr, value);
 }
-
 #endif
 #endif