Add jau/packed_attribute.hpp: Macro __pack(...) for MSC and GCC compatiblw, macro __packed for GCC compatible only

__packed is a simple short for '__attribute__ ((packed))'

__pack(...) wraps the given __VA_ARGS__ to add 'packed' attributes (GCC compatible) or pragmas (MSVC)

2 files changed, 51 insertions, 8 deletions

diff --git a/include/jau/basic_types.hpp b/include/jau/basic_types.hpp
index ffb7109..b1b0d87 100644
--- a/include/jau/basic_types.hpp
+++ b/include/jau/basic_types.hpp
@@ -37,6 +37,8 @@ extern "C" {
     #include <byteswap.h>
 }
 
+#include <jau/packed_attribute.hpp>
+
 namespace jau {
 
     /**
@@ -157,7 +159,7 @@ namespace jau {
     // *************************************************
      */
 
-    struct __attribute__((packed)) uint128_t {
+    __pack( struct uint128_t {
         uint8_t data[16];
 
         constexpr uint128_t() noexcept : data{0} {}
@@ -174,7 +176,7 @@ namespace jau {
         }
         constexpr bool operator!=(uint128_t const &o) const noexcept
         { return !(*this == o); }
-    };
+    } ) ;
 
     constexpr uint128_t bswap(uint128_t const & source) noexcept {
         uint128_t dest;
@@ -186,7 +188,7 @@ namespace jau {
         return dest;
     }
 
-    struct __attribute__((packed)) uint192_t {
+    __pack( struct uint192_t {
         uint8_t data[24];
 
         constexpr uint192_t() noexcept : data{0} {}
@@ -203,7 +205,7 @@ namespace jau {
         }
         constexpr bool operator!=(uint192_t const &o) const noexcept
         { return !(*this == o); }
-    };
+    } );
 
     constexpr uint192_t bswap(uint192_t const & source) noexcept {
         uint192_t dest;
@@ -215,7 +217,7 @@ namespace jau {
         return dest;
     }
 
-    struct __attribute__((packed)) uint256_t {
+    __pack( struct uint256_t {
         uint8_t data[32];
 
         constexpr uint256_t() noexcept : data{0} {}
@@ -232,7 +234,7 @@ namespace jau {
         }
         constexpr bool operator!=(uint256_t const &o) const noexcept
         { return !(*this == o); }
-    };
+    } );
 
     constexpr uint256_t bswap(uint256_t const & source) noexcept {
         uint256_t dest;
@@ -441,10 +443,10 @@ namespace jau {
      * This template shall cause no costs, the cast data pointer is identical to 'T & p = &store'.
      * </p>
      */
-    template<typename T> struct __attribute__((__packed__)) packed_t {
+    template<typename T> __pack ( struct packed_t {
         T store;
         constexpr T get(const bool littleEndian) const noexcept { return littleEndian ? le_to_cpu(store) : be_to_cpu(store); }
-    };
+    } ) ;
 
     inline void put_uint16(uint8_t * buffer, nsize_t const byte_offset, const uint16_t v) noexcept
     {
diff --git a/include/jau/packed_attribute.hpp b/include/jau/packed_attribute.hpp
new file mode 100644
index 0000000..deb29ff
--- /dev/null
+++ b/include/jau/packed_attribute.hpp
@@ -0,0 +1,41 @@
+/*
+ * Copyright (c) 2020 Gothel Software e.K.
+ * Copyright (c) 2020 ZAFENA AB
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining
+ * a copy of this software and associated documentation files (the
+ * "Software"), to deal in the Software without restriction, including
+ * without limitation the rights to use, copy, modify, merge, publish,
+ * distribute, sublicense, and/or sell copies of the Software, and to
+ * permit persons to whom the Software is furnished to do so, subject to
+ * the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be
+ * included in all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+ * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
+ * LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
+ * OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
+ * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ *
+ */
+
+#ifndef PACKED_ATTRIBUTE_HPP_
+#define PACKED_ATTRIBUTE_HPP_
+
+#ifndef __packed
+    #define __packed __attribute__ ((packed))
+#endif
+
+#ifndef __pack
+    #ifdef _MSC_VER
+        #define __pack(...) __pragma( pack(push, 1) ) __VA_ARGS__ __pragma( pack(pop))
+    #else
+        #define __pack(...) __VA_ARGS__ __attribute__ ((packed))
+    #endif
+#endif
+
+#endif /* PACKED_ATTRIBUTE_HPP_ */