--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/libtomcrypt/src/pk/asn1/der/utf8/der_length_utf8_string.c	Thu Jan 11 02:41:05 2007 +0000
@@ -0,0 +1,83 @@
+/* LibTomCrypt, modular cryptographic library -- Tom St Denis
+ *
+ * LibTomCrypt is a library that provides various cryptographic
+ * algorithms in a highly modular and flexible manner.
+ *
+ * The library is free for all purposes without any express
+ * guarantee it works.
+ *
+ * Tom St Denis, [email protected], http://libtomcrypt.com
+ */
+#include "tomcrypt.h"
+
+/**
+  @file der_length_utf8_string.c
+  ASN.1 DER, get length of UTF8 STRING, Tom St Denis
+*/
+
+#ifdef LTC_DER
+
+/** Return the size in bytes of a UTF-8 character
+  @param c   The UTF-8 character to measure
+  @return    The size in bytes
+*/
+unsigned long der_utf8_charsize(const wchar_t c)
+{
+   if (c <= 0x7F) {
+      return 1;
+   } else if (c <= 0x7FF) {
+      return 2;
+   } else if (c <= 0xFFFF) {
+      return 3;
+   } else {
+      return 4;
+   }
+}
+
+/**
+  Gets length of DER encoding of UTF8 STRING 
+  @param in       The characters to measure the length of
+  @param noctets  The number of octets in the string to encode
+  @param outlen   [out] The length of the DER encoding for the given string
+  @return CRYPT_OK if successful
+*/
+int der_length_utf8_string(const wchar_t *in, unsigned long noctets, unsigned long *outlen)
+{
+   unsigned long x, len;
+
+   LTC_ARGCHK(in     != NULL);
+   LTC_ARGCHK(outlen != NULL);
+
+   len = 0;
+   for (x = 0; x < noctets; x++) {
+      if (in[x] < 0 || in[x] > 0x10FFFF) {
+         return CRYPT_INVALID_ARG;
+      }
+      len += der_utf8_charsize(in[x]);
+   }
+
+   if (len < 128) {
+      /* 0C LL DD DD DD ... */
+      *outlen = 2 + len;
+   } else if (len < 256) {
+      /* 0C 81 LL DD DD DD ... */
+      *outlen = 3 + len;
+   } else if (len < 65536UL) {
+      /* 0C 82 LL LL DD DD DD ... */
+      *outlen = 4 + len;
+   } else if (len < 16777216UL) {
+      /* 0C 83 LL LL LL DD DD DD ... */
+      *outlen = 5 + len;
+   } else {
+      return CRYPT_INVALID_ARG;
+   }
+
+   return CRYPT_OK;
+}
+
+#endif
+
+
+/* $Source: /cvs/libtom/libtomcrypt/src/pk/asn1/der/utf8/der_length_utf8_string.c,v $ */
+/* $Revision: 1.5 $ */
+/* $Date: 2006/12/16 17:41:21 $ */