add "portable" alignment macro

3 files changed, 27 insertions, 12 deletions

diff --git a/include/aes/all.h b/include/aes/all.h
index 959e10c..ff27c18 100644
--- a/include/aes/all.h
+++ b/include/aes/all.h
@@ -18,3 +18,4 @@
 #include "error.h"
 #include "mode.h"
 #include "padding.h"
+#include "workarounds.h"
diff --git a/include/aes/workarounds.h b/include/aes/workarounds.h
new file mode 100644
index 0000000..45fece2
--- /dev/null
+++ b/include/aes/workarounds.h
@@ -0,0 +1,14 @@
+// Copyright (c) 2016 Egor Tensin <Egor.Tensin@gmail.com>
+// This file is part of the "AES tools" project.
+// For details, see https://github.com/egor-tensin/aes-tools.
+// Distributed under the MIT License.
+
+#pragma once
+
+#if defined(_MSC_VER)
+#define AES_ALIGN(t, x) __declspec(align(x)) t
+#elif defined(__GNUC__) || defined(__MINGW32__)
+#define AES_ALIGN(t, x) t __attribute__((aligned(x)))
+#else
+#warning "couldn't determine alignment attribute"
+#endif
diff --git a/src/aes.c b/src/aes.c
index 0aded1a..1f7da13 100644
--- a/src/aes.c
+++ b/src/aes.c
@@ -26,7 +26,7 @@ AES_StatusCode aes_AES_format_block(
 
     char* cursor = str->str;
 
-    __declspec(align(16)) unsigned char bytes[16];
+    AES_ALIGN(unsigned char, 16) bytes[16];
     aes_store_block128_aligned(bytes, *block);
 
     for (int i = 0; i < 16; ++i, cursor += 2)
@@ -51,7 +51,7 @@ AES_StatusCode aes_AES_format_block_as_matrix(
 
     char* cursor = str->str;
 
-    __declspec(align(16)) unsigned char bytes[4][4];
+    AES_ALIGN(unsigned char, 16) bytes[4][4];
     aes_store_block128_aligned(bytes, *block);
 
     for (int i = 0; i < 4; ++i, cursor += 3)
@@ -118,7 +118,7 @@ AES_StatusCode aes_AES_parse_block(
 
     const char* cursor = src;
 
-    __declspec(align(16)) unsigned char bytes[16];
+    AES_ALIGN(unsigned char, 16) bytes[16];
 
     for (int i = 0; i < 16; ++i)
     {
@@ -149,7 +149,7 @@ AES_StatusCode aes_AES128_format_key(
 
     char* cursor = str->str;
 
-    __declspec(align(16)) unsigned char bytes[16];
+    AES_ALIGN(unsigned char, 16) bytes[16];
     aes_store_block128_aligned(bytes, key->key);
 
     for (int i = 0; i < 16; ++i, cursor += 2)
@@ -175,7 +175,7 @@ AES_StatusCode aes_AES192_format_key(
     char* cursor = str->str;
 
     {
-        __declspec(align(16)) unsigned char bytes[16];
+        AES_ALIGN(unsigned char, 16) bytes[16];
         aes_store_block128_aligned(bytes, key->lo);
 
         for (int i = 0; i < 16; ++i, cursor += 2)
@@ -183,7 +183,7 @@ AES_StatusCode aes_AES192_format_key(
     }
 
     {
-        __declspec(align(16)) unsigned char bytes[16];
+        AES_ALIGN(unsigned char, 16) bytes[16];
         aes_store_block128_aligned(bytes, key->hi);
 
         for (int i = 0; i < 8; ++i, cursor += 2)
@@ -210,7 +210,7 @@ AES_StatusCode aes_AES256_format_key(
     char* cursor = str->str;
 
     {
-        __declspec(align(16)) unsigned char bytes[16];
+        AES_ALIGN(unsigned char, 16) bytes[16];
         aes_store_block128_aligned(bytes, key->lo);
 
         for (int i = 0; i < 16; ++i, cursor += 2)
@@ -218,7 +218,7 @@ AES_StatusCode aes_AES256_format_key(
     }
 
     {
-        __declspec(align(16)) unsigned char bytes[16];
+        AES_ALIGN(unsigned char, 16) bytes[16];
         aes_store_block128_aligned(bytes, key->hi);
 
         for (int i = 0; i < 16; ++i, cursor += 2)
@@ -298,7 +298,7 @@ AES_StatusCode aes_AES192_parse_key(
     const char* cursor = src;
 
     {
-        __declspec(align(16)) unsigned char bytes[16];
+        AES_ALIGN(unsigned char, 16) bytes[16];
 
         for (int i = 0; i < 16; ++i)
         {
@@ -314,7 +314,7 @@ AES_StatusCode aes_AES192_parse_key(
     }
 
     {
-        __declspec(align(16)) unsigned char bytes[16];
+        AES_ALIGN(unsigned char, 16) bytes[16];
 
         for (int i = 0; i < 8; ++i)
         {
@@ -349,7 +349,7 @@ AES_StatusCode aes_AES256_parse_key(
     const char* cursor = src;
 
     {
-        __declspec(align(16)) unsigned char bytes[16];
+        AES_ALIGN(unsigned char, 16) bytes[16];
 
         for (int i = 0; i < 16; ++i)
         {
@@ -365,7 +365,7 @@ AES_StatusCode aes_AES256_parse_key(
     }
 
     {
-        __declspec(align(16)) unsigned char bytes[16];
+        AES_ALIGN(unsigned char, 16) bytes[16];
 
         for (int i = 0; i < 16; ++i)
         {