1 files changed, 81 insertions, 0 deletions
diff --git a/newlib/libc/stdio/wbuf.c b/newlib/libc/stdio/wbuf.c
new file mode 100644
index 00000000000..1106829713b
--- /dev/null
+++ b/newlib/libc/stdio/wbuf.c
@@ -0,0 +1,81 @@
+/* No user fns here.  Pesch 15apr92. */
+
+/*
+ * Copyright (c) 1990 The Regents of the University of California.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms are permitted
+ * provided that the above copyright notice and this paragraph are
+ * duplicated in all such forms and that any documentation,
+ * advertising materials, and other materials related to such
+ * distribution and use acknowledge that the software was developed
+ * by the University of California, Berkeley.  The name of the
+ * University may not be used to endorse or promote products derived
+ * from this software without specific prior written permission.
+ * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
+ * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
+ * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
+ */
+
+#if defined(LIBC_SCCS) && !defined(lint)
+static char sccsid[] = "%W% (Berkeley) %G%";
+#endif /* LIBC_SCCS and not lint */
+
+#include <stdio.h>
+#include "local.h"
+#include "fvwrite.h"
+
+/*
+ * Write the given character into the (probably full) buffer for
+ * the given file.  Flush the buffer out if it is or becomes full,
+ * or if c=='\n' and the file is line buffered.
+ */
+
+int
+__swbuf (c, fp)
+     register int c;
+     register FILE *fp;
+{
+  register int n;
+
+  /* Ensure stdio has been initialized.  */
+
+  CHECK_INIT (fp);
+
+  /*
+   * In case we cannot write, or longjmp takes us out early,
+   * make sure _w is 0 (if fully- or un-buffered) or -_bf._size
+   * (if line buffered) so that we will get called again.
+   * If we did not do this, a sufficient number of putc()
+   * calls might wrap _w from negative to positive.
+   */
+
+  fp->_w = fp->_lbfsize;
+  if (cantwrite (fp))
+    return EOF;
+  c = (unsigned char) c;
+
+  /*
+   * If it is completely full, flush it out.  Then, in any case,
+   * stuff c into the buffer.  If this causes the buffer to fill
+   * completely, or if c is '\n' and the file is line buffered,
+   * flush it (perhaps a second time).  The second flush will always
+   * happen on unbuffered streams, where _bf._size==1; fflush()
+   * guarantees that putc() will always call wbuf() by setting _w
+   * to 0, so we need not do anything else.
+   */
+
+  n = fp->_p - fp->_bf._base;
+  if (n >= fp->_bf._size)
+    {
+      if (fflush (fp))
+	return EOF;
+      n = 0;
+    }
+  fp->_w--;
+  *fp->_p++ = c;
+  if (++n == fp->_bf._size || (fp->_flags & __SLBF && c == '\n'))
+    if (fflush (fp))
+      return EOF;
+  return c;
+}