Add C++ compatibility isc/stdatomic.h header modeled after P0943R1

lib/isc/include/isc/Makefile.in

@@ -32,7 +32,7 @@ HEADERS =	aes.h app.h assertions.h backtrace.h base32.h base64.h \
 		radix.h random.h ratelimiter.h refcount.h regex.h \
 		region.h resource.h result.h resultclass.h rwlock.h \
 		safe.h serial.h sha1.h sha2.h sockaddr.h socket.h \
-		stats.h stdio.h stdlib.h string.h symtab.h \
+		stats.h stdatomic.h stdio.h stdlib.h string.h symtab.h \
 	        task.h taskpool.h timer.h tm.h types.h util.h version.h \
 		xml.h
 

lib/isc/include/isc/refcount.h

@@ -22,7 +22,7 @@
 #include <isc/types.h>
 
 #if defined(ISC_PLATFORM_HAVESTDATOMIC)
-#include <stdatomic.h>
+#include <isc/stdatomic.h>
 #endif
 
 /*! \file isc/refcount.h

lib/isc/include/isc/rwlock.h

@@ -22,7 +22,7 @@
 
 #if defined(ISC_PLATFORM_HAVESTDATOMIC)
 #include <stdint.h>
-#include <stdatomic.h>
+#include <isc/stdatomic.h>
 #endif
 
 ISC_LANG_BEGINDECLS

lib/isc/include/isc/stdatomic.h

@@ -0,0 +1,79 @@
+/*
+ * Copyright (C) Internet Systems Consortium, Inc. ("ISC")
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ *
+ * See the COPYRIGHT file distributed with this work for additional
+ * information regarding copyright ownership.
+ */
+
+/*! \file isc/stdatomic.h
+ * \brief This header includes proper atomic headers for C or C++
+ */
+
+#pragma once
+
+#ifdef __cplusplus
+#include <atomic>
+#define _Atomic(T) std::atomic<T>
+
+using std::memory_order;
+using std::memory_order_relaxed;
+using std::memory_order_consume;
+using std::memory_order_acquire;
+using std::memory_order_release;
+using std::memory_order_acq_rel;
+using std::memory_order_seq_cst;
+
+using std::atomic_flag;
+
+using std::atomic_bool;
+using std::atomic_char;
+using std::atomic_schar;
+using std::atomic_uchar;
+using std::atomic_short;
+using std::atomic_ushort;
+using std::atomic_int;
+using std::atomic_uint;
+using std::atomic_long;
+using std::atomic_ulong;
+using std::atomic_llong;
+using std::atomic_ullong;
+using std::atomic_char16_t;
+using std::atomic_char32_t;
+using std::atomic_wchar_t;
+using std::atomic_int8_t;
+using std::atomic_uint8_t;
+using std::atomic_int16_t;
+using std::atomic_uint16_t;
+using std::atomic_int32_t;
+using std::atomic_uint32_t;
+using std::atomic_int64_t;
+using std::atomic_uint64_t;
+using std::atomic_int_least8_t;
+using std::atomic_uint_least8_t;
+using std::atomic_int_least16_t;
+using std::atomic_uint_least16_t;
+using std::atomic_int_least32_t;
+using std::atomic_uint_least32_t;
+using std::atomic_int_least64_t;
+using std::atomic_uint_least64_t;
+using std::atomic_int_fast8_t;
+using std::atomic_uint_fast8_t;
+using std::atomic_int_fast16_t;
+using std::atomic_uint_fast16_t;
+using std::atomic_int_fast32_t;
+using std::atomic_uint_fast32_t;
+using std::atomic_int_fast64_t;
+using std::atomic_uint_fast64_t;
+using std::atomic_intptr_t;
+using std::atomic_uintptr_t;
+using std::atomic_size_t;
+using std::atomic_ptrdiff_t;
+using std::atomic_intmax_t;
+using std::atomic_uintmax_t;
+#else /* not __cplusplus */
+#include <stdatomic.h>
+#endif /* __cplusplus */

lib/isc/stats.c

@@ -27,7 +27,7 @@
 #include <isc/util.h>
 
 #if defined(ISC_PLATFORM_HAVESTDATOMIC)
-#include <stdatomic.h>
+#include <isc/stdatomic.h>
 #endif
 
 #define ISC_STATS_MAGIC			ISC_MAGIC('S', 't', 'a', 't')

util/copyrights

@@ -3595,6 +3595,7 @@
 ./lib/isc/include/isc/sockaddr.h		C	1998,1999,2000,2001,2002,2003,2004,2005,2006,2007,2009,2012,2015,2016,2018
 ./lib/isc/include/isc/socket.h			C	1998,1999,2000,2001,2002,2004,2005,2006,2007,2008,2009,2011,2012,2013,2014,2016,2018
 ./lib/isc/include/isc/stats.h			C	2009,2012,2016,2018
+./lib/isc/include/isc/stdatomic.h		C	2018
 ./lib/isc/include/isc/stdio.h			C	2000,2001,2004,2005,2006,2007,2013,2016,2018
 ./lib/isc/include/isc/stdlib.h			C	2003,2004,2005,2006,2007,2016,2018
 ./lib/isc/include/isc/string.h			C	2000,2001,2003,2004,2005,2006,2007,2014,2016,2018