add libip

src/libip/myetheraddr.c

@@ -0,0 +1,41 @@
+#include <u.h>
+#include <libc.h>
+#include <ip.h>
+
+int
+myetheraddr(uchar *to, char *dev)
+{
+	int n, fd;
+	char buf[256], *ptr;
+
+	/* Make one exist */
+	if(*dev == '/')
+		sprint(buf, "%s/clone", dev);
+	else
+		sprint(buf, "/net/%s/clone", dev);
+	fd = open(buf, ORDWR);
+	if(fd >= 0)
+		close(fd);
+
+	if(*dev == '/')
+		sprint(buf, "%s/0/stats", dev);
+	else
+		sprint(buf, "/net/%s/0/stats", dev);
+	fd = open(buf, OREAD);
+	if(fd < 0)
+		return -1;
+
+	n = read(fd, buf, sizeof(buf)-1);
+	close(fd);
+	if(n <= 0)
+		return -1;
+	buf[n] = 0;
+
+	ptr = strstr(buf, "addr: ");
+	if(!ptr)
+		return -1;
+	ptr += 6;
+
+	parseether(to, ptr);
+	return 0;
+}