add initial symbols to config and checks to check_config to allow use of macros to define standard functions
diff --git a/include/polarssl/check_config.h b/include/polarssl/check_config.h
index 51745c9..eb2fecd 100644
--- a/include/polarssl/check_config.h
+++ b/include/polarssl/check_config.h
@@ -198,14 +198,65 @@
 #error "POLARSSL_PKCS11_C defined, but not all prerequisites"
 #endif
 
+#if defined(POLARSSL_PLATFORM_ENABLE_FUNCTION_MACROS) &&\
+    !defined(POLARSSL_PLATFORM_C)
+#error "POLARSSL_PLATFORM_ENABLE_FUNCTION_MACROS defined, but not prerequisites"
+#endif
+
 #if defined(POLARSSL_PLATFORM_EXIT_ALT) && !defined(POLARSSL_PLATFORM_C)
 #error "POLARSSL_PLATFORM_EXIT_ALT defined, but not all prerequisites"
 #endif
 
+#if defined(POLARSSL_PLATFORM_EXIT_MACRO) &&\
+    ( !defined(POLARSSL_PLATFORM_C) ||\
+        !defined(POLARSSL_PLATFORM_ENABLE_FUNCTION_MACROS) )
+#error "POLARSSL_PLATFORM_EXIT_MACRO defined, but not all prerequisites"
+#endif
+
+#if defined(POLARSSL_PLATFORM_EXIT_MACRO) &&\
+    ( defined(POLARSSL_PLATFORM_STD_EXIT) ||\
+        defined(POLARSSL_PLATFORM_EXIT_ALT) )
+#error "POLARSSL_PLATFORM_EXIT_MACRO and POLARSSL_PLATFORM_STD_EXIT/POLARSSL_PLATFORM_EXIT_ALT cannot be defined simultaneously"
+#endif
+
 #if defined(POLARSSL_PLATFORM_FPRINTF_ALT) && !defined(POLARSSL_PLATFORM_C)
 #error "POLARSSL_PLATFORM_FPRINTF_ALT defined, but not all prerequisites"
 #endif
 
+#if defined(POLARSSL_PLATFORM_FPRINTF_MACRO) &&\
+    ( !defined(POLARSSL_PLATFORM_C) ||\
+        !defined(POLARSSL_PLATFORM_ENABLE_FUNCTION_MACROS) )
+#error "POLARSSL_PLATFORM_FPRINTF_MACRO defined, but not all prerequisites"
+#endif
+
+#if defined(POLARSSL_PLATFORM_FPRINTF_MACRO) &&\
+    ( defined(POLARSSL_PLATFORM_STD_FPRINTF) ||\
+        defined(POLARSSL_PLATFORM_FPRINTF_ALT) )
+#error "POLARSSL_PLATFORM_FPRINTF_MACRO and POLARSSL_PLATFORM_STD_FPRINTF/POLARSSL_PLATFORM_FPRINTF_ALT cannot be defined simultaneously"
+#endif
+
+#if defined(POLARSSL_PLATFORM_FREE_MACRO) &&\
+    ( !defined(POLARSSL_PLATFORM_C) || !defined(POLARSSL_PLATFORM_MEMORY) ||\
+        !defined(POLARSSL_PLATFORM_ENABLE_FUNCTION_MACROS) )
+#error "POLARSSL_PLATFORM_FREE_MACRO defined, but not all prerequisites"
+#endif
+
+#if defined(POLARSSL_PLATFORM_FREE_MACRO) &&\
+    defined(POLARSSL_PLATFORM_STD_FREE)
+#error "POLARSSL_PLATFORM_FREE_MACRO and POLARSSL_PLATFORM_STD_FREE cannot be defined simultaneously"
+#endif
+
+#if defined(POLARSSL_PLATFORM_MALLOC_MACRO) &&\
+    ( !defined(POLARSSL_PLATFORM_C) || !defined(POLARSSL_PLATFORM_MEMORY) ||\
+        !defined(POLARSSL_PLATFORM_ENABLE_FUNCTION_MACROS) )
+#error "POLARSSL_PLATFORM_MALLOC_MACRO defined, but not all prerequisites"
+#endif
+
+#if defined(POLARSSL_PLATFORM_MALLOC_MACRO) &&\
+    defined(POLARSSL_PLATFORM_STD_MALLOC)
+#error "POLARSSL_PLATFORM_MALLOC_MACRO and POLARSSL_PLATFORM_STD_MALLOC cannot be defined simultaneously"
+#endif
+
 #if defined(POLARSSL_PLATFORM_MEMORY) && !defined(POLARSSL_PLATFORM_C)
 #error "POLARSSL_PLATFORM_MEMORY defined, but not all prerequisites"
 #endif
@@ -214,6 +265,18 @@
 #error "POLARSSL_PLATFORM_PRINTF_ALT defined, but not all prerequisites"
 #endif
 
+#if defined(POLARSSL_PLATFORM_PRINTF_MACRO) &&\
+    ( !defined(POLARSSL_PLATFORM_C) ||\
+        !defined(POLARSSL_PLATFORM_ENABLE_FUNCTION_MACROS) )
+#error "POLARSSL_PLATFORM_PRINTF_MACRO defined, but not all prerequisites"
+#endif
+
+#if defined(POLARSSL_PLATFORM_PRINTF_MACRO) &&\
+    ( defined(POLARSSL_PLATFORM_STD_PRINTF) ||\
+        defined(POLARSSL_PLATFORM_PRINTF_ALT) )
+#error "POLARSSL_PLATFORM_PRINTF_MACRO and POLARSSL_PLATFORM_STD_PRINTF/POLARSSL_PLATFORM_PRINTF_ALT cannot be defined simultaneously"
+#endif
+
 #if defined(POLARSSL_PLATFORM_SNPRINTF_ALT) && !defined(POLARSSL_PLATFORM_C)
 #error "POLARSSL_PLATFORM_SNPRINTF_ALT defined, but not all prerequisites"
 #endif
@@ -223,6 +286,18 @@
 #error "POLARSSL_PLATFORM_SNPRINTF_ALT defined but not available on Windows"
 #endif
 
+#if defined(POLARSSL_PLATFORM_SNPRINTF_MACRO) &&\
+    ( !defined(POLARSSL_PLATFORM_C) ||\
+        !defined(POLARSSL_PLATFORM_ENABLE_FUNCTION_MACROS) )
+#error "POLARSSL_PLATFORM_SNPRINTF_MACRO defined, but not all prerequisites"
+#endif
+
+#if defined(POLARSSL_PLATFORM_SNPRINTF_MACRO) &&\
+    ( defined(POLARSSL_PLATFORM_STD_SNPRINTF) ||\
+        defined(POLARSSL_PLATFORM_SNPRINTF_ALT) )
+#error "POLARSSL_PLATFORM_SNPRINTF_MACRO and POLARSSL_PLATFORM_STD_SNPRINTF/POLARSSL_PLATFORM_SNPRINTF_ALT cannot be defined simultaneously"
+#endif
+
 #if defined(POLARSSL_PLATFORM_STD_MEM_HDR) &&\
     !defined(POLARSSL_PLATFORM_NO_STD_FUNCTIONS)
 #error "POLARSSL_PLATFORM_STD_MEM_HDR defined, but not all prerequisites"