1 files changed, 75 insertions, 0 deletions
diff --git a/StdLib/LibC/Stdio/ungetwc.c b/StdLib/LibC/Stdio/ungetwc.c
new file mode 100644
index 0000000000..8155043cf7
--- /dev/null
+++ b/StdLib/LibC/Stdio/ungetwc.c
@@ -0,0 +1,75 @@
+/*-
+ * Copyright (c)2001 Citrus Project,
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ *
+ * $Citrus$
+
+  NetBSD: ungetwc.c,v 1.3 2005/06/12 05:21:27 lukem Exp
+ */
+#include  <LibConfig.h>
+#include  <sys/EfiCdefs.h>
+
+#include  <assert.h>
+#include  <errno.h>
+#include  <stdio.h>
+#include  <wchar.h>
+#include  "reentrant.h"
+#include  "local.h"
+
+wint_t
+ungetwc(wint_t wc, FILE *fp)
+{
+  struct wchar_io_data *wcio;
+
+  _DIAGASSERT(fp);
+
+  if (wc == WEOF)
+    return WEOF;
+
+  FLOCKFILE(fp);
+  _SET_ORIENTATION(fp, 1);
+  /*
+   * XXX since we have no way to transform a wchar string to
+   * a char string in reverse order, we can't use ungetc.
+   */
+  /* XXX should we flush ungetc buffer? */
+
+  wcio = WCIO_GET(fp);
+  if (wcio == 0) {
+    FUNLOCKFILE(fp);
+    errno = ENOMEM; /* XXX */
+    return WEOF;
+  }
+
+  if (wcio->wcio_ungetwc_inbuf >= WCIO_UNGETWC_BUFSIZE) {
+    FUNLOCKFILE(fp);
+    return WEOF;
+  }
+
+  wcio->wcio_ungetwc_buf[wcio->wcio_ungetwc_inbuf++] = (wchar_t)wc;
+  __sclearerr(fp);
+  FUNLOCKFILE(fp);
+
+  return wc;
+}