Diff: DHCPClient.cpp

Revision:

0:db4242c89949

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/DHCPClient.cpp	Tue Apr 10 03:38:22 2012 +0000
@@ -0,0 +1,100 @@
+// DHCPClient.cpp 2012/4/10
+// DHCP Client for WIZ820io(W5200)
+#include "mbed.h"
+#include "MyEthernetNetIf.h"
+#include "MyUDPSocket.h"
+#include "DHCPClient.h"
+#ifdef DEBUG
+#include "Utils.h"
+#endif //DEBUG
+
+static DHCPClient* _g_dhcp;
+static void _DHCP_OnEvent(UDPSocketEvent e)
+{
+    _g_dhcp->callback(e);
+}
+
+int DHCPClient::offer_ack(uint8_t buf[], int size) {
+    memcpy(yiaddr, &buf[DHCP_OFFSET_YIADDR], 4);   
+    uint8_t *p;
+    int msg_type = -1;
+    p = buf + DHCP_OFFSET_OPTIONS;
+    while(*p != 0xff && p < (uint8_t*)&buf[DHCP_MAX_PACKET_SIZE]) {
+        int code = *p++;
+        if (code == 0x00) {
+            continue;
+        }
+        int len = *p++;
+#ifdef DHCP_VERBOSE           
+        char codeStr[24];
+        snprintf(codeStr, sizeof(codeStr), "DHCP option: %d", code);
+        printfBytes(codeStr, p, len);
+#endif //DHCP_VERBOSE
+        if (code == 53) {
+           msg_type = *p;
+        } else if (code == 1) {
+            memcpy(netmask, p, 4); // Subnet mask address
+        } else if (code == 3) {
+            memcpy(gateway, p, 4); // Gateway IP address 
+        } else if (code == 6) {// DNS
+            memcpy(dnsaddr, p, 4);
+        }
+        p += len;
+    }
+    return msg_type;
+}
+
+void DHCPClient::callback(UDPSocketEvent e)
+{
+    PRINT_FUNC();
+    uint8_t buf[DHCP_MAX_PACKET_SIZE];
+    Host host;
+    int len = p_udp->recvfrom((char*)buf, sizeof(buf), &host);
+    if (!verify(buf, len)) {
+        return;
+    }
+    int r = offer_ack(buf, len);
+    if (r == 2) { // OFFER
+        request(buf, 300);
+        Host server(IpAddr(255,255,255,255), 67); // DHCP broadcast
+        p_udp->sendto((char*)buf, 300, &server);
+    } else if (r == 5) { // ACK
+        exit_flag = true;
+    }
+}
+
+int DHCPClient::setup(int timeout_ms)
+{
+    Timer t;
+    t.start();
+    p_udp = new MyUDPSocket;
+    p_udp->setOnEvent(_DHCP_OnEvent);
+    Host local(IpAddr(0,0,0,0), 68);
+    Host server(IpAddr(255,255,255,255), 67); // DHCP broadcast
+    p_udp->bind(local);
+    uint8_t buf[300];
+    discover(buf, sizeof(buf));
+    p_udp->sendto((char*)buf, sizeof(buf), &server);
+    exit_flag = false;
+    int err = 0;
+    while(1) {
+        p_udp->poll();
+        if (exit_flag) {
+            break;
+        }
+        if (t.read_ms() > timeout_ms) {
+            err = -1;
+            break;
+        }
+#ifdef DEBUG            
+        wait_ms(100);
+#endif //DEBUG
+    }
+    delete p_udp;
+    return err;
+}
+
+DHCPClient::DHCPClient()
+{
+    _g_dhcp = this;
+}