Standard Libraries for EDK II.

[mirror_edk2.git] / StdLib / LibC / Stdio / ungetwc.c

diff --git a/StdLib/LibC/Stdio/ungetwc.c b/StdLib/LibC/Stdio/ungetwc.c
new file mode 100644 (file)
index 0000000..8155043
--- /dev/null
+++ b/StdLib/LibC/Stdio/ungetwc.c
@@ -0,0 +1,75 @@
+/*-\r
+ * Copyright (c)2001 Citrus Project,\r
+ * All rights reserved.\r
+ *\r
+ * Redistribution and use in source and binary forms, with or without\r
+ * modification, are permitted provided that the following conditions\r
+ * are met:\r
+ * 1. Redistributions of source code must retain the above copyright\r
+ *    notice, this list of conditions and the following disclaimer.\r
+ * 2. Redistributions in binary form must reproduce the above copyright\r
+ *    notice, this list of conditions and the following disclaimer in the\r
+ *    documentation and/or other materials provided with the distribution.\r
+ *\r
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND\r
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE\r
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE\r
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE\r
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL\r
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS\r
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)\r
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT\r
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY\r
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF\r
+ * SUCH DAMAGE.\r
+ *\r
+ * $Citrus$\r
+\r
+  NetBSD: ungetwc.c,v 1.3 2005/06/12 05:21:27 lukem Exp\r
+ */\r
+#include  <LibConfig.h>\r
+#include  <sys/EfiCdefs.h>\r
+\r
+#include  <assert.h>\r
+#include  <errno.h>\r
+#include  <stdio.h>\r
+#include  <wchar.h>\r
+#include  "reentrant.h"\r
+#include  "local.h"\r
+\r
+wint_t\r
+ungetwc(wint_t wc, FILE *fp)\r
+{\r
+  struct wchar_io_data *wcio;\r
+\r
+  _DIAGASSERT(fp);\r
+\r
+  if (wc == WEOF)\r
+    return WEOF;\r
+\r
+  FLOCKFILE(fp);\r
+  _SET_ORIENTATION(fp, 1);\r
+  /*\r
+   * XXX since we have no way to transform a wchar string to\r
+   * a char string in reverse order, we can't use ungetc.\r
+   */\r
+  /* XXX should we flush ungetc buffer? */\r
+\r
+  wcio = WCIO_GET(fp);\r
+  if (wcio == 0) {\r
+    FUNLOCKFILE(fp);\r
+    errno = ENOMEM; /* XXX */\r
+    return WEOF;\r
+  }\r
+\r
+  if (wcio->wcio_ungetwc_inbuf >= WCIO_UNGETWC_BUFSIZE) {\r
+    FUNLOCKFILE(fp);\r
+    return WEOF;\r
+  }\r
+\r
+  wcio->wcio_ungetwc_buf[wcio->wcio_ungetwc_inbuf++] = (wchar_t)wc;\r
+  __sclearerr(fp);\r
+  FUNLOCKFILE(fp);\r
+\r
+  return wc;\r
+}\r