sync nfc-utils.h/c and mifare.c/h with libnfc's ones.

src/nfc-utils.h

@@ -38,6 +38,46 @@
 
 #  include <stdlib.h>
 #  include <string.h>
+#  include <err.h>
+
+/**
+ * @macro DBG
+ * @brief Print a message of standard output only in DEBUG mode
+ */
+#ifdef DEBUG
+#  define DBG(...) do { \
+    warnx ("DBG %s:%d", __FILE__, __LINE__); \
+    warnx ("    " __VA_ARGS__ ); \
+  } while (0)
+#else
+#  define DBG(...) {}
+#endif
+
+/**
+ * @macro WARN
+ * @brief Print a warn message
+ */
+#ifdef DEBUG
+#  define WARN(...) do { \
+    warnx ("WARNING %s:%d", __FILE__, __LINE__); \
+    warnx ("    " __VA_ARGS__ ); \
+  } while (0)
+#else
+#  define WARN(...) warnx ("WARNING: " __VA_ARGS__ )
+#endif
+
+/**
+ * @macro ERR
+ * @brief Print a error message
+ */
+#ifdef DEBUG
+#  define ERR(...) do { \
+    warnx ("ERROR %s:%d", __FILE__, __LINE__); \
+    warnx ("    " __VA_ARGS__ ); \
+  } while (0)
+#else
+#  define ERR(...)  warnx ("ERROR: " __VA_ARGS__ )
+#endif
 
 byte_t  oddparity (const byte_t bt);
 void    oddparity_byte_ts (const byte_t * pbtData, const size_t szLen, byte_t * pbtPar);