Fix ret code in aescrypt2.c
diff --git a/programs/aes/aescrypt2.c b/programs/aes/aescrypt2.c
index 4acf38d..31daf1e 100644
--- a/programs/aes/aescrypt2.c
+++ b/programs/aes/aescrypt2.c
@@ -29,9 +29,12 @@
 #include "mbedtls/platform.h"
 #else
 #include <stdio.h>
-#define mbedtls_fprintf    fprintf
-#define mbedtls_printf     printf
-#endif
+#include <stdlib.h>
+#define mbedtls_fprintf         fprintf
+#define mbedtls_printf          printf
+#define MBEDTLS_EXTI_SUCCESS    EXIT_SUCCESS
+#define MBEDTLS_EXIT_FAILURE    EXIT_FAILURE
+#endif /* MBEDTLS_PLATFORM_C */
 
 #include "mbedtls/aes.h"
 #include "mbedtls/md.h"
@@ -71,7 +74,8 @@
 #else
 int main( int argc, char *argv[] )
 {
-    int ret = 1;
+    int ret = 0;
+    int exit_code = MBEDTLS_EXIT_FAILURE;
 
     unsigned int i, n;
     int mode, lastn;
@@ -429,7 +433,7 @@
         }
     }
 
-    ret = 0;
+    exit_code = MBEDTLS_EXIT_SUCCESS;
 
 exit:
     if( fin )
@@ -452,6 +456,6 @@
     mbedtls_aes_free( &aes_ctx );
     mbedtls_md_free( &sha_ctx );
 
-    return( ret );
+    return( exit_code );
 }
 #endif /* MBEDTLS_AES_C && MBEDTLS_SHA256_C && MBEDTLS_FS_IO */