1 files changed, 115 insertions, 0 deletions
diff --git a/newlib/libc/stdio/ungetwc.c b/newlib/libc/stdio/ungetwc.c
new file mode 100644
index 0000000..234d2f7
--- /dev/null
+++ b/newlib/libc/stdio/ungetwc.c
@@ -0,0 +1,115 @@
+/*-
+ * Copyright (c) 2002-2004 Tim J. Robbins.
+ * 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.
+ */
+
+/*
+FUNCTION
+<<ungetwc>>---push wide character data back into a stream
+
+INDEX
+        ungetwc
+INDEX
+        _ungetwc_r
+
+ANSI_SYNOPSIS
+        #include <stdio.h>
+        #include <wchar.h>
+        wint_t ungetwc(wint_t <[wc]>, FILE *<[stream]>);
+
+        wint_t _ungetwc_r(struct _reent *<[reent]>, wint_t <[wc]>, FILE *<[stream]>);
+
+DESCRIPTION
+<<ungetwc>> is used to return wide characters back to <[stream]> to be
+read again.  If <[wc]> is WEOF, the stream is unchanged.  Otherwise, the
+wide character <[wc]> is put back on the stream, and subsequent reads will see
+the wide chars pushed back in reverse order.  Pushed wide chars are lost if the
+stream is repositioned, such as by <<fseek>>, <<fsetpos>>, or
+<<rewind>>.
+
+The underlying file is not changed, but it is possible to push back
+something different than what was originally read.  Ungetting a
+character will clear the end-of-stream marker, and decrement the file
+position indicator.  Pushing back beyond the beginning of a file gives
+unspecified behavior.
+
+The alternate function <<_ungetwc_r>> is a reentrant version.  The
+extra argument <[reent]> is a pointer to a reentrancy structure.
+
+RETURNS
+The wide character pushed back, or <<WEOF>> on error.
+
+PORTABILITY
+C99
+*/
+
+#include <_ansi.h>
+#include <reent.h>
+#include <errno.h>
+#include <limits.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <wchar.h>
+#include "local.h"
+
+wint_t
+_DEFUN(_ungetwc_r, (ptr, wc, fp),
+	struct _reent *ptr _AND
+	wint_t wc _AND
+	register FILE *fp)
+{
+  char buf[MB_LEN_MAX];
+  size_t len;
+
+  _flockfile (fp);
+  ORIENT (fp, 1);
+  if (wc == WEOF)
+    wc = WEOF;
+  else if ((len = _wcrtomb_r(ptr, buf, wc, &fp->_mbstate)) == (size_t)-1)
+    {
+      fp->_flags |= __SERR;
+      wc = WEOF;
+    }
+  else
+    while (len-- != 0)
+      if (_ungetc_r(ptr, (unsigned char)buf[len], fp) == EOF)
+	{
+	  wc = WEOF;
+	  break;
+	}
+  _funlockfile (fp);
+  return wc;
+}
+
+/*
+ * MT-safe version.
+ */
+wint_t
+_DEFUN(ungetwc, (wint_t wc, FILE *fp),
+	wint_t wc _AND
+	FILE *fp)
+{
+  CHECK_INIT (_REENT, fp);
+  return _ungetwc_r (_REENT, wc, fp);
+}