Comment cleanups.

[pdclib] / functions / stdio / ungetc.c

diff --git a/functions/stdio/ungetc.c b/functions/stdio/ungetc.c
index c355afcd0c7c4b9f7f5336f3ac5ad94a93a470db..dd0295917e4af81cdee2334f33e4a90f73656e8e 100644 (file)
--- a/functions/stdio/ungetc.c
+++ b/functions/stdio/ungetc.c
@@ -1,8 +1,31 @@
-// ----------------------------------------------------------------------------
-// $Id$
-// ----------------------------------------------------------------------------
-// Public Domain C Library - http://pdclib.sourceforge.net
-// This code is Public Domain. Use, modify, and redistribute at will.
-// ----------------------------------------------------------------------------
-
-int ungetc( int c, FILE * stream ) { /* TODO */ };
+/* ungetc( int, FILE * )
+
+   This file is part of the Public Domain C Library (PDCLib).
+   Permission is granted to use, modify, and / or redistribute at will.
+*/
+
+#include <stdio.h>
+
+#ifndef REGTEST
+
+int ungetc( int c, struct _PDCLIB_file_t * stream )
+{
+    if ( c == EOF || stream->ungetidx == _PDCLIB_UNGETCBUFSIZE )
+    {
+        return -1;
+    }
+    return stream->ungetbuf[stream->ungetidx++] = (unsigned char) c;
+}
+
+#endif
+
+#ifdef TEST
+#include <_PDCLIB_test.h>
+
+int main( void )
+{
+    /* Testing covered by ftell.c */
+    return TEST_RESULTS;
+}
+
+#endif