NetworkSocketAPI / NetworkSocketAPI

Base class for IP Based Networking Libraries

Dependencies:   DnsQuery

Dependents:   TempTower BSDInterfaceTests HelloBSDInterface ESP8266InterfaceTests ... more

For a complete getting started guide see the wiki...

Network Socket API

The Network Socket API provides a common interface for using sockets on network devices. The API provides a simple class-based interface that should be familiar to users experienced with other socket APIs. Additionally, the API provides a simple interface for implementing network devices, making it easy to connect hardware agnostic programs to new devices.

Network Interfaces

The NetworkInterface provides an abstract class for network devices that support sockets. Devices should provide a DeviceInterface class that inherits this interface and adds implementation specific methods for using the device. A NetworkInterface must be provided to a Socket constructor to open a socket on the interface. Currently two subclasses are defined for common devices, EthernetInterface and WiFiInterface.

Sockets

The Socket class is used for managing network sockets. Once opened, the socket provides a pipe through which data can sent and recieved to a specific endpoint. The socket class can be instantiated as either a TCPSocket or a UDPSocket which defines the protocol used for the connection.

Diff: SocketAddress.cpp

Revision:
100:90d8f662de83
Parent:
97:68232387bc75
Child:
105:2fd212f8da61
--- a/SocketAddress.cpp	Tue Apr 19 18:25:12 2016 -0500
+++ b/SocketAddress.cpp	Tue Apr 19 18:25:23 2016 -0500
@@ -19,7 +19,8 @@
 #include <string.h>
 #include "mbed.h"
 
-static bool address_is_ipv4(const char *addr)
+
+static bool ipv4_is_valid(const char *addr)
 {
     int i = 0;
 
@@ -38,7 +39,7 @@
     return true;
 }
 
-static bool address_is_ipv6(const char *addr)
+static bool ipv6_is_valid(const char *addr)
 {
     // Check each digit for [0-9a-fA-F:]
     for (int i = 0; addr[i]; i++) {
@@ -53,20 +54,57 @@
     return true;
 }
 
-static void address_to_ipv4(uint8_t *bytes, const char *addr)
+static void ipv4_from_address(uint8_t *bytes, const char *addr)
 {
-    sscanf(addr, "%hhd.%hhd.%hhd.%hhd", &bytes[0], &bytes[1], &bytes[2], &bytes[3]);
+    sscanf(addr, "%hhu.%hhu.%hhu.%hhu", &bytes[0], &bytes[1], &bytes[2], &bytes[3]);
 }
 
-static void address_to_ipv6(uint8_t *bytes, const char *addr)
+static int ipv6_scan_chunk(uint16_t *shorts, const char *chunk) {
+    int count = 0;
+    int i = 0;
+
+    for (; count < NSAPI_IPv6_BYTES/2; count++) {
+        int scanned = sscanf(&chunk[i], "%hx", &shorts[count]);
+        if (scanned < 1) {
+            return count;
+        }
+
+        for (; chunk[i] != ':'; i++) {
+            if (!chunk[i]) {
+                return count+1;
+            }
+        }
+
+        i++;
+    }
+
+    return count;
+}
+
+static void ipv6_from_address(uint8_t *bytes, const char *addr)
 {
-    // TODO support short form (::1, 2001::ffee:100a)
-    // Use a more intellegent algorithm
+    // Start with zeroed address
     uint16_t shorts[NSAPI_IPv6_BYTES/2];
-    sscanf(addr, "%hx:%hx:%hx:%hx:%hx:%hx:%hx:%hx",
-            &shorts[0], &shorts[1], &shorts[2], &shorts[3],
-            &shorts[4], &shorts[5], &shorts[6], &shorts[7]);
+    memset(shorts, 0, sizeof shorts);
+
+    int suffix = 0;
 
+    // Find double colons and scan suffix
+    for (int i = 0; addr[i]; i++) {
+        if (addr[i] == ':' && addr[i+1] == ':') {
+            suffix = ipv6_scan_chunk(shorts, &addr[i+2]);
+            break;
+        }
+    }
+
+    // Move suffix to end
+    memmove(&shorts[NSAPI_IPv6_BYTES/2-suffix], &shorts[0],
+            suffix*sizeof(uint16_t));
+
+    // Scan prefix
+    ipv6_scan_chunk(shorts, &addr[0]);
+
+    // Flip bytes
     for (int i = 0; i < NSAPI_IPv6_BYTES/2; i++) {
         bytes[2*i+0] = (uint8_t)(shorts[i] >> 8);
         bytes[2*i+1] = (uint8_t)(shorts[i] >> 0);
@@ -80,31 +118,23 @@
 
 static void ipv6_to_address(char *addr, const uint8_t *bytes)
 {
-    int pos = 0;
-    for (int i = 0; i < NSAPI_IPv6_BYTES; i+=2) {
-        int ret = sprintf(&addr[pos], "%02x%02x", bytes[i], bytes[i+1]);
-        if (ret < 0) {
-            memset(addr, 0, NSAPI_IPv6_SIZE + 1);
-            return;
-        }
-        pos += ret;
+    for (int i = 0; i < NSAPI_IPv6_BYTES/2; i++) {
+        sprintf(&addr[5*i], "%02x%02x", bytes[2*i], bytes[2*i+1]);
+        addr[5*i+4] = ':';
+    }
+    addr[NSAPI_IPv6_SIZE-1] = '\0';
+}
 
-        addr[pos++] = ':';
-    }
-    pos -= 1; // Overwrite last ':'
-    addr[pos++] = '\0';
-    MBED_ASSERT(NSAPI_IPv6_SIZE == pos);
-}
 
 SocketAddress::SocketAddress(NetworkInterface *iface, const char *host, uint16_t port)
 {
     // Check for valid IP addresses
-    if (host && address_is_ipv4(host)) {
+    if (host && ipv4_is_valid(host)) {
         _ip_version = NSAPI_IPv4;
-        address_to_ipv4(_ip_bytes, host);
-    } else if (host && address_is_ipv6(host)) {
+        ipv4_from_address(_ip_bytes, host);
+    } else if (host && ipv6_is_valid(host)) {
         _ip_version = NSAPI_IPv6;
-        address_to_ipv4(_ip_bytes, host);
+        ipv4_from_address(_ip_bytes, host);
     } else {
         // DNS lookup
         int err = iface->gethostbyname(this, host);
@@ -140,12 +170,12 @@
 {
     _ip_address[0] = '\0';
 
-    if (addr && address_is_ipv4(addr)) {
+    if (addr && ipv4_is_valid(addr)) {
         _ip_version = NSAPI_IPv4;
-        address_to_ipv4(_ip_bytes, addr);
-    } else if (addr && address_is_ipv6(addr)) {
+        ipv4_from_address(_ip_bytes, addr);
+    } else if (addr && ipv6_is_valid(addr)) {
         _ip_version = NSAPI_IPv6;
-        address_to_ipv6(_ip_bytes, addr);
+        ipv6_from_address(_ip_bytes, addr);
     } else {
         _ip_version = NSAPI_IPv4;
         memset(_ip_bytes, 0, NSAPI_IPv4_BYTES);