Diff: uip/lc-addrlabels.h

Revision:

0:685224d2f66d

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/uip/lc-addrlabels.h	Sat Jun 14 16:02:21 2014 +0000
@@ -0,0 +1,83 @@
+/*
+ * Copyright (c) 2004-2005, Swedish Institute of Computer Science.
+ * 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.
+ * 3. Neither the name of the Institute nor the names of its contributors
+ *    may be used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE 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 INSTITUTE 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.
+ *
+ * This file is part of the uIP TCP/IP stack
+ *
+ * Author: Adam Dunkels <adam@sics.se>
+ *
+ * $Id: lc-addrlabels.h,v 1.3 2006/06/12 08:00:30 adam Exp $
+ */
+
+/**
+ * \addtogroup lc
+ * @{
+ */
+
+/**
+ * \file
+ * Implementation of local continuations based on the "Labels as
+ * values" feature of gcc
+ * \author
+ * Adam Dunkels <adam@sics.se>
+ *
+ * This implementation of local continuations is based on a special
+ * feature of the GCC C compiler called "labels as values". This
+ * feature allows assigning pointers with the address of the code
+ * corresponding to a particular C label.
+ *
+ * For more information, see the GCC documentation:
+ * http://gcc.gnu.org/onlinedocs/gcc/Labels-as-Values.html
+ *
+ * Thanks to dividuum for finding the nice local scope label
+ * implementation.
+ */
+
+#ifndef __LC_ADDRLABELS_H__
+#define __LC_ADDRLABELS_H__
+
+/** \hideinitializer */
+typedef void * lc_t;
+
+#define LC_INIT(s) s = NULL
+
+
+#define LC_RESUME(s)                            \
+  do {                                          \
+    if(s != NULL) {                             \
+      goto *s;                                  \
+    }                                           \
+  } while(0)
+
+#define LC_SET(s)                               \
+  do { ({ __label__ resume; resume: (s) = &&resume; }); }while(0)
+
+#define LC_END(s)
+
+#endif /* __LC_ADDRLABELS_H__ */
+
+/**  @} */