--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/3rdparty/vmime/contrib/punycode/punycode.h	Tue Aug 17 11:19:54 2021 +0200
@@ -0,0 +1,84 @@
+/*
+punycode.h from RFC 3492
+http://www.nicemice.net/idn/
+Adam M. Costello
+http://www.nicemice.net/amc/
+
+This is ANSI C code (C89) implementing Punycode (RFC 3492).
+
+*/
+
+#include <limits.h>
+
+enum punycode_status {
+  punycode_success,
+  punycode_bad_input,   /* Input is invalid.                       */
+  punycode_big_output,  /* Output would exceed the space provided. */
+  punycode_overflow     /* Input needs wider integers to process.  */
+};
+
+#if UINT_MAX >= (1 << 26) - 1
+typedef unsigned int punycode_uint;
+#else
+typedef unsigned long punycode_uint;
+#endif
+
+enum punycode_status punycode_encode(
+  punycode_uint input_length,
+  const punycode_uint input[],
+  const unsigned char case_flags[],
+  punycode_uint *output_length,
+  char output[] );
+
+    /* punycode_encode() converts Unicode to Punycode.  The input     */
+    /* is represented as an array of Unicode code points (not code    */
+    /* units; surrogate pairs are not allowed), and the output        */
+    /* will be represented as an array of ASCII code points.  The     */
+    /* output string is *not* null-terminated; it will contain        */
+    /* zeros if and only if the input contains zeros.  (Of course     */
+    /* the caller can leave room for a terminator and add one if      */
+    /* needed.)  The input_length is the number of code points in     */
+    /* the input.  The output_length is an in/out argument: the       */
+    /* caller passes in the maximum number of code points that it     */
+    /* can receive, and on successful return it will contain the      */
+    /* number of code points actually output.  The case_flags array   */
+    /* holds input_length boolean values, where nonzero suggests that */
+    /* the corresponding Unicode character be forced to uppercase     */
+    /* after being decoded (if possible), and zero suggests that      */
+    /* it be forced to lowercase (if possible).  ASCII code points    */
+    /* are encoded literally, except that ASCII letters are forced    */
+    /* to uppercase or lowercase according to the corresponding       */
+    /* uppercase flags.  If case_flags is a null pointer then ASCII   */
+    /* letters are left as they are, and other code points are        */
+    /* treated as if their uppercase flags were zero.  The return     */
+    /* value can be any of the punycode_status values defined above   */
+    /* except punycode_bad_input; if not punycode_success, then       */
+    /* output_size and output might contain garbage.                  */
+
+enum punycode_status punycode_decode(
+  punycode_uint input_length,
+  const char input[],
+  punycode_uint *output_length,
+  punycode_uint output[],
+  unsigned char case_flags[] );
+
+    /* punycode_decode() converts Punycode to Unicode.  The input is  */
+    /* represented as an array of ASCII code points, and the output   */
+    /* will be represented as an array of Unicode code points.  The   */
+    /* input_length is the number of code points in the input.  The   */
+    /* output_length is an in/out argument: the caller passes in      */
+    /* the maximum number of code points that it can receive, and     */
+    /* on successful return it will contain the actual number of      */
+    /* code points output.  The case_flags array needs room for at    */
+    /* least output_length values, or it can be a null pointer if the */
+    /* case information is not needed.  A nonzero flag suggests that  */
+    /* the corresponding Unicode character be forced to uppercase     */
+    /* by the caller (if possible), while zero suggests that it be    */
+    /* forced to lowercase (if possible).  ASCII code points are      */
+    /* output already in the proper case, but their flags will be set */
+    /* appropriately so that applying the flags would be harmless.    */
+    /* The return value can be any of the punycode_status values      */
+    /* defined above; if not punycode_success, then output_length,    */
+    /* output, and case_flags might contain garbage.  On success, the */
+    /* decoder will never need to write an output_length greater than */
+    /* input_length, because of how the encoding is defined.          */