wprobe: move measurement task to the kernel, add some configurability (work in progress)

[openwrt/staging/florian.git] / package / wprobe / src / user / wprobe.c

diff --git a/package/wprobe/src/user/wprobe.c b/package/wprobe/src/user/wprobe.c
index 1f8df6c7e99e4503eefd6648d58cbf2f930d5926..e48f768e54a3847c2bc164705da62c3685099f8f 100644 (file)
--- a/package/wprobe/src/user/wprobe.c
+++ b/package/wprobe/src/user/wprobe.c
@@ -35,6 +35,7 @@
 #define DPRINTF(fmt, ...) do {} while (0)
 #endif
 
+static int n_devs = 0;
 static struct nl_sock *handle = NULL;
 static struct nl_cache *cache = NULL;
 static struct genl_family *family = NULL;
@@ -83,9 +84,16 @@ ack_handler(struct nl_msg *msg, void *arg)
 }
 
 
-void
+static void
 wprobe_free(void)
 {
+       /* should not happen */
+       if (n_devs == 0)
+               return;
+
+       if (--n_devs != 0)
+               return;
+
        if (cache)
                nl_cache_free(cache);
        if (handle)
@@ -94,11 +102,14 @@ wprobe_free(void)
        cache = NULL;
 }
 
-int
+static int
 wprobe_init(void)
 {
        int ret;
 
+       if (n_devs++ > 0)
+               return 0;
+
        handle = nl_socket_alloc();
        if (!handle) {
                DPRINTF("Failed to create handle\n");
@@ -233,8 +244,8 @@ save_attribute_handler(struct nl_msg *msg, void *arg)
 }
 
 
-int
-wprobe_dump_attributes(const char *ifname, bool link, struct list_head *list, char *addr)
+static int
+dump_attributes(const char *ifname, bool link, struct list_head *list, char *addr)
 {
        struct nl_msg *msg;
        struct wprobe_attr_cb cb;
@@ -255,6 +266,64 @@ nla_put_failure:
        return -EINVAL;
 }
 
+struct wprobe_iface *
+wprobe_get_dev(const char *ifname)
+{
+       struct wprobe_iface *dev;
+
+       if (wprobe_init() != 0)
+               return NULL;
+
+       dev = malloc(sizeof(struct wprobe_iface));
+       if (!dev)
+               return NULL;
+
+       memset(dev, 0, sizeof(struct wprobe_iface));
+       dev->ifname = strdup(ifname);
+       if (!dev->ifname)
+               goto error;
+
+       dev->interval = -1;
+       dev->scale_min = -1;
+       dev->scale_max = -1;
+       dev->scale_m = -1;
+       dev->scale_d = -1;
+
+       INIT_LIST_HEAD(&dev->global_attr);
+       INIT_LIST_HEAD(&dev->link_attr);
+       INIT_LIST_HEAD(&dev->links);
+
+       dump_attributes(ifname, false, &dev->global_attr, NULL);
+       dump_attributes(ifname, true, &dev->link_attr, NULL);
+
+       return dev;
+
+error:
+       free(dev);
+       return NULL;
+}
+
+static void
+free_attr_list(struct list_head *list)
+{
+       struct wprobe_attribute *attr, *tmp;
+
+       list_for_each_entry_safe(attr, tmp, list, list) {
+               list_del(&attr->list);
+               free(attr);
+       }
+}
+
+void
+wprobe_free_dev(struct wprobe_iface *dev)
+{
+       wprobe_free();
+       free_attr_list(&dev->global_attr);
+       free_attr_list(&dev->link_attr);
+       free((void *)dev->ifname);
+       free(dev);
+}
+
 static struct wprobe_link *
 get_link(struct list_head *list, const char *addr)
 {
@@ -313,7 +382,7 @@ save_link_handler(struct nl_msg *msg, void *arg)
 
 
 int
-wprobe_update_links(const char *ifname, struct list_head *list)
+wprobe_update_links(struct wprobe_iface *dev)
 {
        struct wprobe_link *l, *tmp;
        struct nl_msg *msg;
@@ -321,10 +390,10 @@ wprobe_update_links(const char *ifname, struct list_head *list)
        int err;
 
        INIT_LIST_HEAD(&cb.old_list);
-       list_splice_init(list, &cb.old_list);
-       cb.list = list;
+       list_splice_init(&dev->links, &cb.old_list);
+       cb.list = &dev->links;
 
-       msg = wprobe_new_msg(ifname, WPROBE_CMD_GET_LINKS, true);
+       msg = wprobe_new_msg(dev->ifname, WPROBE_CMD_GET_LINKS, true);
        if (!msg)
                return -ENOMEM;
 
@@ -340,16 +409,37 @@ wprobe_update_links(const char *ifname, struct list_head *list)
        return 0;
 }
 
-void
-wprobe_measure(const char *ifname)
+int
+wprobe_apply_config(struct wprobe_iface *dev)
 {
        struct nl_msg *msg;
 
-       msg = wprobe_new_msg(ifname, WPROBE_CMD_MEASURE, false);
+       msg = wprobe_new_msg(dev->ifname, WPROBE_CMD_CONFIG, false);
        if (!msg)
-               return;
+               return -ENOMEM;
+
+       if (dev->interval >= 0)
+               NLA_PUT_MSECS(msg, WPROBE_ATTR_INTERVAL, dev->interval);
+
+       wprobe_send_msg(msg, NULL, NULL);
+       return 0;
+
+nla_put_failure:
+       nlmsg_free(msg);
+       return -ENOMEM;
+}
+
+int
+wprobe_measure(struct wprobe_iface *dev)
+{
+       struct nl_msg *msg;
+
+       msg = wprobe_new_msg(dev->ifname, WPROBE_CMD_MEASURE, false);
+       if (!msg)
+               return -ENOMEM;
 
        wprobe_send_msg(msg, NULL, NULL);
+       return 0;
 }
 
 struct wprobe_request_cb {
@@ -431,6 +521,10 @@ found:
                if (attr->val.n > 0) {
                        float avg = ((float) attr->val.s) / attr->val.n;
                        float stdev = sqrt((((float) attr->val.ss) / attr->val.n) - (avg * avg));
+                       if (isnan(stdev))
+                               stdev = 0.0f;
+                       if (isnan(avg))
+                               avg = 0.0f;
                        attr->val.avg = avg;
                        attr->val.stdev = stdev;
                }
@@ -443,25 +537,24 @@ out:
 
 
 int
-wprobe_request_data(const char *ifname, struct list_head *attrs, const unsigned char *addr, int scale)
+wprobe_request_data(struct wprobe_iface *dev, const unsigned char *addr)
 {
        struct wprobe_request_cb cb;
+       struct list_head *attrs;
        struct nl_msg *msg;
        int err;
 
-       msg = wprobe_new_msg(ifname, WPROBE_CMD_GET_INFO, true);
+       msg = wprobe_new_msg(dev->ifname, WPROBE_CMD_GET_INFO, true);
        if (!msg)
                return -ENOMEM;
 
-       if (scale < 0)
-               NLA_PUT_U32(msg, WPROBE_ATTR_FLAGS, WPROBE_F_RESET);
-       else if (scale > 0)
-               NLA_PUT_U32(msg, WPROBE_ATTR_SCALE, scale);
-
-       if (addr)
+       if (addr) {
+               attrs = &dev->link_attr;
                NLA_PUT(msg, WPROBE_ATTR_MAC, 6, addr);
+       } else {
+               attrs = &dev->global_attr;
+       }
 
-nla_put_failure:
        INIT_LIST_HEAD(&cb.old_list);
        list_splice_init(attrs, &cb.old_list);
        cb.list = attrs;
@@ -469,6 +562,10 @@ nla_put_failure:
        err = wprobe_send_msg(msg, save_attrdata_handler, &cb);
        list_splice(&cb.old_list, attrs->prev);
        return err;
+
+nla_put_failure:
+       nlmsg_free(msg);
+       return -ENOMEM;
 }