opal/util: add function to obtain interface speed

If kernel ethtool_cmd_speed() is not available, use copies if possible.

Signed-off-by: Karol Mroz <mroz.karol@gmail.com>

opal/util/Makefile.am

@@ -43,6 +43,7 @@ headers = \
         cmd_line.h \
         crc.h \
         daemon_init.h \
+	ethtool.h \
         error.h \
         fd.h \
         few.h \
@@ -78,6 +79,7 @@ libopalutil_la_SOURCES = \
         cmd_line.c \
         crc.c \
         daemon_init.c \
+	ethtool.c \
         error.c \
         fd.c \
         few.c \

opal/util/ethtool.c

@@ -0,0 +1,83 @@
+/*
+ * Copyright (c) 2016 Karol Mroz.  All rights reserved.
+ * $COPYRIGHT$
+ *
+ * Additional copyrights may follow
+ *
+ * $HEADER$
+ */
+
+#include "opal_config.h"
+
+#include <string.h>
+#include <limits.h>
+
+#ifdef HAVE_UNISTD_H
+#include <unistd.h>
+#endif
+#ifdef HAVE_NET_IF_H
+#include <net/if.h>
+#endif
+#ifdef HAVE_LINUX_ETHTOOL_H
+#include <linux/ethtool.h>
+#endif
+#ifdef HAVE_SYS_IOCTL_H
+#include <sys/ioctl.h>
+#endif
+#ifdef HAVE_LINUX_SOCKIOS_H
+#include <linux/sockios.h>
+#endif
+
+#include "opal/util/ethtool.h"
+#include "opal/util/if.h"
+
+#if !defined(HAVE_DECL_ETHTOOL_CMD_SPEED)
+static inline unsigned int
+ethtool_cmd_speed(const struct ethtool_cmd *ep)
+{
+    return (ep->speed_hi << 16) | ep->speed;
+}
+#endif
+
+/*
+ * Obtain an appropriate bandwidth for the interface if_name. On Linux, we
+ * get this via an ioctl(). Elsewhere or in the error case, we return the
+ * speed as 0.
+ */
+unsigned int
+opal_ethtool_get_speed (const char *if_name)
+{
+    unsigned int speed = 0;
+
+#if defined(HAVE_DECL_SIOCETHTOOL) && defined(HAVE_STRUCT_IFREQ) && defined(HAVE_STRUCT_ETHTOOL_CMD)
+    int sockfd;
+    struct ifreq ifr;
+    struct ethtool_cmd edata = {
+        .cmd = ETHTOOL_GSET,
+    };
+
+    sockfd = socket(PF_INET, SOCK_DGRAM, 0);
+    if (sockfd < 0) {
+        goto out;
+    }
+
+    memset(&ifr, 0, sizeof(struct ifreq));
+    strncpy(ifr.ifr_name, if_name, IF_NAMESIZE);
+    ifr.ifr_data = (char *)&edata;
+
+    if (ioctl(sockfd, SIOCETHTOOL, &ifr) < 0) {
+        goto out;
+    }
+
+    speed = ethtool_cmd_speed(&edata);
+    if (UINT_MAX == speed) {
+        speed = 0;
+    }
+
+out:
+    close(sockfd);
+    return speed;
+#else
+    return speed;
+#endif
+}

opal/util/ethtool.h

@@ -0,0 +1,20 @@
+/*
+ * Copyright (c) 2016 Karol Mroz.  All rights reserved.
+ * $COPYRIGHT$
+ *
+ * Additional copyrights may follow
+ *
+ * $HEADER$
+ */
+
+#ifndef OPAL_ETHTOOL_H
+#define OPAL_ETHTOOL_H
+
+/*
+ * Obtain an appropriate bandwidth for the interface if_name. On Linux, we
+ * get this via an ioctl(). Elsewhere or in the error case, we return the
+ * speed as 0.
+ */
+unsigned int opal_ethtool_get_speed(const char *if_name);
+
+#endif