1 files changed, 76 insertions, 0 deletions
diff --git a/src/wsbm_atomic.h b/src/wsbm_atomic.h
new file mode 100644
index 0000000..7be2da9
--- /dev/null
+++ b/src/wsbm_atomic.h
@@ -0,0 +1,76 @@
+/**
+ * This file is under no copyright claims due to its
+ * simplicity.
+ */
+
+#ifndef _WSBM_ATOMIC_H_
+#define _WSBM_ATOMIC_H_
+
+#include <stdint.h>
+
+struct _WsbmAtomic
+{
+    int32_t count;
+};
+
+#define wsbmAtomicInit(_i) {(i)}
+#define wsbmAtomicSet(_v, _i) (((_v)->count) = (_i))
+#define wsbmAtomicRead(_v) ((_v)->count)
+
+static inline int
+wsbmAtomicIncZero(struct _WsbmAtomic *v)
+{
+    unsigned char c;
+    __asm__ __volatile__("lock; incl %0; sete %1":"+m"(v->count), "=qm"(c)
+			 ::"memory");
+
+    return c != 0;
+}
+
+static inline int
+wsbmAtomicDecNegative(struct _WsbmAtomic *v)
+{
+    unsigned char c;
+    int i = -1;
+    __asm__ __volatile__("lock; addl %2,%0; sets %1":"+m"(v->count), "=qm"(c)
+			 :"ir"(i):"memory");
+
+    return c;
+}
+
+static inline int
+wsbmAtomicDecZero(struct _WsbmAtomic *v)
+{
+    unsigned char c;
+
+    __asm__ __volatile__("lock; decl %0; sete %1":"+m"(v->count), "=qm"(c)
+			 ::"memory");
+
+    return c != 0;
+}
+
+static inline void
+wsbmAtomicInc(struct _WsbmAtomic *v)
+{
+    __asm__ __volatile__("lock; incl %0":"+m"(v->count));
+}
+
+static inline void
+wsbmAtomicDec(struct _WsbmAtomic *v)
+{
+    __asm__ __volatile__("lock; decl %0":"+m"(v->count));
+}
+
+static inline int32_t
+wsbmAtomicCmpXchg(volatile struct _WsbmAtomic *v, int32_t old, int32_t new)
+{
+    int32_t previous;
+
+    __asm__ __volatile__("lock; cmpxchgl %k1,%2":"=a"(previous)
+			 :"r"(new), "m"(v->count), "0"(old)
+			 :"memory");
+
+    return previous;
+}
+
+#endif