+\f
+/* Unicode string normalization. */
+
+/* This function is a partial clone of SCM_STRING_TO_U32_BUF from
+ libguile/i18n.c. It would be useful to have this factored out into a more
+ convenient location, but its use of alloca makes that tricky to do. */
+
+static SCM
+normalize_str (SCM string, uninorm_t form)
+{
+ SCM ret;
+ scm_t_uint32 *w_str;
+ scm_t_wchar *cbuf;
+ size_t rlen, len = scm_i_string_length (string);
+
+ if (scm_i_is_narrow_string (string))
+ {
+ size_t i;
+ const char *buf = scm_i_string_chars (string);
+
+ w_str = alloca (sizeof (scm_t_wchar) * (len + 1));
+
+ for (i = 0; i < len; i ++)
+ w_str[i] = (unsigned char) buf[i];
+ w_str[len] = 0;
+ }
+ else
+ w_str = (scm_t_uint32 *) scm_i_string_wide_chars (string);
+
+ w_str = u32_normalize (form, w_str, len, NULL, &rlen);
+
+ ret = scm_i_make_wide_string (rlen, &cbuf);
+ u32_cpy ((scm_t_uint32 *) cbuf, w_str, rlen);
+ free (w_str);
+
+ scm_i_try_narrow_string (ret);
+
+ return ret;
+}
+
+SCM_DEFINE (scm_string_normalize_nfc, "string-normalize-nfc", 1, 0, 0,
+ (SCM string),
+ "Returns the NFC normalized form of @var{string}.")
+#define FUNC_NAME s_scm_string_normalize_nfc
+{
+ SCM_VALIDATE_STRING (1, string);
+ return normalize_str (string, UNINORM_NFC);
+}
+#undef FUNC_NAME
+
+SCM_DEFINE (scm_string_normalize_nfd, "string-normalize-nfd", 1, 0, 0,
+ (SCM string),
+ "Returns the NFD normalized form of @var{string}.")
+#define FUNC_NAME s_scm_string_normalize_nfd
+{
+ SCM_VALIDATE_STRING (1, string);
+ return normalize_str (string, UNINORM_NFD);
+}
+#undef FUNC_NAME
+
+SCM_DEFINE (scm_string_normalize_nfkc, "string-normalize-nfkc", 1, 0, 0,
+ (SCM string),
+ "Returns the NFKC normalized form of @var{string}.")
+#define FUNC_NAME s_scm_string_normalize_nfkc
+{
+ SCM_VALIDATE_STRING (1, string);
+ return normalize_str (string, UNINORM_NFKC);
+}
+#undef FUNC_NAME
+
+SCM_DEFINE (scm_string_normalize_nfkd, "string-normalize-nfkd", 1, 0, 0,
+ (SCM string),
+ "Returns the NFKD normalized form of @var{string}.")
+#define FUNC_NAME s_scm_string_normalize_nfkd
+{
+ SCM_VALIDATE_STRING (1, string);
+ return normalize_str (string, UNINORM_NFKD);
+}
+#undef FUNC_NAME
+