Move the FORTIFY_SOURCE helpers over to .cpp.

Change-Id: Ib5067d51b983cac7760c975becce7fe2408ead04
diff --git a/libc/bionic/__memcpy_chk.cpp b/libc/bionic/__memcpy_chk.cpp
new file mode 100644
index 0000000..991ff02
--- /dev/null
+++ b/libc/bionic/__memcpy_chk.cpp
@@ -0,0 +1,56 @@
+/*
+ * Copyright (C) 2012 The Android Open Source Project
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *  * Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ *  * 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 COPYRIGHT HOLDERS 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
+ * COPYRIGHT OWNER 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.
+ */
+
+#undef _FORTIFY_SOURCE
+#include <string.h>
+#include <stdlib.h>
+#include <private/logd.h>
+
+/*
+ * Runtime implementation of __memcpy_chk.
+ *
+ * See
+ *   http://gcc.gnu.org/onlinedocs/gcc/Object-Size-Checking.html
+ *   http://gcc.gnu.org/ml/gcc-patches/2004-09/msg02055.html
+ * for details.
+ *
+ * This memcpy check is called if _FORTIFY_SOURCE is defined and
+ * greater than 0.
+ */
+extern "C" void *__memcpy_chk(void *dest, const void *src,
+              size_t copy_amount, size_t dest_len)
+{
+    if (__builtin_expect(copy_amount > dest_len, 0)) {
+        __libc_android_log_print(ANDROID_LOG_FATAL, "libc",
+            "*** memcpy buffer overflow detected ***\n");
+        __libc_android_log_event_uid(BIONIC_EVENT_MEMCPY_BUFFER_OVERFLOW);
+        abort();
+    }
+
+    return memcpy(dest, src, copy_amount);
+}