1 files changed, 56 insertions, 0 deletions
diff --git a/tools/build/atomic.c b/tools/build/atomic.c
new file mode 100644
index 0000000..72eef9f
--- /dev/null
+++ b/tools/build/atomic.c
@@ -0,0 +1,56 @@
+/*-
+ * Copyright (c) 2011 Marcel Moolenaar
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ *
+ * $FreeBSD$
+ */
+
+#include <stdint.h>
+
+uint32_t __sync_add_and_fetch_4(uint32_t *, uint32_t);
+uint32_t __sync_sub_and_fetch_4(uint32_t *, uint32_t);
+uint32_t __sync_val_compare_and_swap_4(uint32_t *, uint32_t, uint32_t);
+
+uint32_t
+__sync_add_and_fetch_4(uint32_t *ptr, uint32_t val)
+{
+	*ptr += val;
+	return *ptr;
+}
+
+uint32_t
+__sync_sub_and_fetch_4(uint32_t *ptr, uint32_t val)
+{
+	*ptr -= val;
+	return *ptr;
+}
+
+uint32_t
+__sync_val_compare_and_swap_4(uint32_t *ptr, uint32_t oldval, uint32_t newval)
+{
+	uint32_t res = *ptr;
+	if (res == oldval)
+		*ptr = newval;
+	return res;
+}