1 files changed, 64 insertions, 0 deletions
diff --git a/lib/unicase/u-is-invariant.h b/lib/unicase/u-is-invariant.h
new file mode 100644
index 00000000..e6b7fbb4
--- /dev/null
+++ b/lib/unicase/u-is-invariant.h
@@ -0,0 +1,64 @@
+/* Test whether a Unicode string is invariant under a given case mapping.
+   Copyright (C) 2009 Free Software Foundation, Inc.
+   Written by Bruno Haible <bruno@clisp.org>, 2009.
+
+   This program is free software: you can redistribute it and/or modify it
+   under the terms of the GNU Lesser General Public License as published
+   by the Free Software Foundation; either version 3 of the License, or
+   (at your option) any later version.
+
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public License
+   along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
+
+int
+FUNC (const UNIT *s, size_t n,
+      UNIT * (*mapping) (const UNIT *s, size_t n, const char *iso639_language,
+			 uninorm_t nf,
+			 UNIT *resultbuf, size_t *lengthp),
+      const char *iso639_language,
+      bool *resultp)
+{
+  UNIT normsbuf[2048 / sizeof (UNIT)];
+  UNIT *norms;
+  size_t norms_length;
+  UNIT mappedbuf[2048 / sizeof (UNIT)];
+  UNIT *mapped;
+  size_t mapped_length;
+
+  /* Apply canonical decomposition to S.  */
+  norms_length = sizeof (normsbuf) / sizeof (UNIT);
+  norms = U_NORMALIZE (UNINORM_NFD, s, n, normsbuf, &norms_length);
+  if (norms == NULL)
+    /* errno is set here.  */
+    return -1;
+
+  /* Apply mapping.  */
+  mapped_length = sizeof (mappedbuf) / sizeof (UNIT);
+  mapped = mapping (norms, norms_length, iso639_language, NULL,
+		    mappedbuf, &mapped_length);
+  if (mapped == NULL)
+    {
+      if (norms != normsbuf)
+	{
+	  int saved_errno = errno;
+	  free (norms);
+	  errno = saved_errno;
+	}
+      return -1;
+    }
+
+  /* Compare.  */
+  *resultp = (mapped_length == norms_length
+	      && U_CMP (mapped, norms, norms_length) == 0);
+
+  if (mapped != mappedbuf)
+    free (mapped);
+  if (norms != normsbuf)
+    free (norms);
+  return 0;
+}