initial checkin of lwip, enough to build

[netwatch.git] / lwip / src / core / ipv4 / ip_addr.c

diff --git a/lwip/src/core/ipv4/ip_addr.c b/lwip/src/core/ipv4/ip_addr.c
new file mode 100644 (file)
index 0000000..94bf467
--- /dev/null
+++ b/lwip/src/core/ipv4/ip_addr.c
@@ -0,0 +1,84 @@
+/**
+ * @file
+ * This is the IPv4 address tools implementation.
+ *
+ */
+
+/*
+ * Copyright (c) 2001-2004 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. The name of the author may not be used to endorse or promote products
+ *    derived from this software without specific prior written permission. 
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``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 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 lwIP TCP/IP stack.
+ * 
+ * Author: Adam Dunkels <adam@sics.se>
+ *
+ */
+
+#include "lwip/opt.h"
+#include "lwip/ip_addr.h"
+#include "lwip/inet.h"
+#include "lwip/netif.h"
+
+#define IP_ADDR_ANY_VALUE 0x00000000UL
+#define IP_ADDR_BROADCAST_VALUE 0xffffffffUL
+
+/* used by IP_ADDR_ANY and IP_ADDR_BROADCAST in ip_addr.h */
+const struct ip_addr ip_addr_any = { IP_ADDR_ANY_VALUE };
+const struct ip_addr ip_addr_broadcast = { IP_ADDR_BROADCAST_VALUE };
+
+/**
+ * Determine if an address is a broadcast address on a network interface 
+ * 
+ * @param addr address to be checked
+ * @param netif the network interface against which the address is checked
+ * @return returns non-zero if the address is a broadcast address
+ */
+u8_t ip_addr_isbroadcast(struct ip_addr *addr, struct netif *netif)
+{
+  u32_t addr2test;
+
+  addr2test = addr->addr;
+  /* all ones (broadcast) or all zeroes (old skool broadcast) */
+  if ((~addr2test == IP_ADDR_ANY_VALUE) ||
+      (addr2test == IP_ADDR_ANY_VALUE))
+    return 1;
+  /* no broadcast support on this network interface? */
+  else if ((netif->flags & NETIF_FLAG_BROADCAST) == 0)
+    /* the given address cannot be a broadcast address
+     * nor can we check against any broadcast addresses */
+    return 0;
+  /* address matches network interface address exactly? => no broadcast */
+  else if (addr2test == netif->ip_addr.addr)
+    return 0;
+  /*  on the same (sub) network... */
+  else if (ip_addr_netcmp(addr, &(netif->ip_addr), &(netif->netmask))
+         /* ...and host identifier bits are all ones? =>... */
+          && ((addr2test & ~netif->netmask.addr) ==
+           (IP_ADDR_BROADCAST_VALUE & ~netif->netmask.addr)))
+    /* => network broadcast address */
+    return 1;
+  else
+    return 0;
+}