libnetlink: Add filter function to rtnl_neighdump_req

[mirror_iproute2.git] / lib / ll_map.c

diff --git a/lib/ll_map.c b/lib/ll_map.c
index e69de29bb2d1d6434b8b29ae775ad8c2e48c5391..1ab8ef0758ac566072bea9882a0baa379ae5c2d0 100644 (file)
--- a/lib/ll_map.c
+++ b/lib/ll_map.c
@@ -0,0 +1,231 @@
+/*
+ * ll_map.c
+ *
+ *             This program is free software; you can redistribute it and/or
+ *             modify it under the terms of the GNU General Public License
+ *             as published by the Free Software Foundation; either version
+ *             2 of the License, or (at your option) any later version.
+ *
+ * Authors:    Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru>
+ *
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <fcntl.h>
+#include <sys/socket.h>
+#include <netinet/in.h>
+#include <string.h>
+#include <net/if.h>
+
+#include "libnetlink.h"
+#include "ll_map.h"
+#include "list.h"
+
+struct ll_cache {
+       struct hlist_node idx_hash;
+       struct hlist_node name_hash;
+       unsigned        flags;
+       unsigned        index;
+       unsigned short  type;
+       char            name[];
+};
+
+#define IDXMAP_SIZE    1024
+static struct hlist_head idx_head[IDXMAP_SIZE];
+static struct hlist_head name_head[IDXMAP_SIZE];
+
+static struct ll_cache *ll_get_by_index(unsigned index)
+{
+       struct hlist_node *n;
+       unsigned h = index & (IDXMAP_SIZE - 1);
+
+       hlist_for_each(n, &idx_head[h]) {
+               struct ll_cache *im
+                       = container_of(n, struct ll_cache, idx_hash);
+               if (im->index == index)
+                       return im;
+       }
+
+       return NULL;
+}
+
+unsigned namehash(const char *str)
+{
+       unsigned hash = 5381;
+
+       while (*str)
+               hash = ((hash << 5) + hash) + *str++; /* hash * 33 + c */
+
+       return hash;
+}
+
+static struct ll_cache *ll_get_by_name(const char *name)
+{
+       struct hlist_node *n;
+       unsigned h = namehash(name) & (IDXMAP_SIZE - 1);
+
+       hlist_for_each(n, &name_head[h]) {
+               struct ll_cache *im
+                       = container_of(n, struct ll_cache, name_hash);
+
+               if (strncmp(im->name, name, IFNAMSIZ) == 0)
+                       return im;
+       }
+
+       return NULL;
+}
+
+int ll_remember_index(struct nlmsghdr *n, void *arg)
+{
+       unsigned int h;
+       const char *ifname;
+       struct ifinfomsg *ifi = NLMSG_DATA(n);
+       struct ll_cache *im;
+       struct rtattr *tb[IFLA_MAX+1];
+
+       if (n->nlmsg_type != RTM_NEWLINK && n->nlmsg_type != RTM_DELLINK)
+               return 0;
+
+       if (n->nlmsg_len < NLMSG_LENGTH(sizeof(*ifi)))
+               return -1;
+
+       im = ll_get_by_index(ifi->ifi_index);
+       if (n->nlmsg_type == RTM_DELLINK) {
+               if (im) {
+                       hlist_del(&im->name_hash);
+                       hlist_del(&im->idx_hash);
+                       free(im);
+               }
+               return 0;
+       }
+
+       parse_rtattr(tb, IFLA_MAX, IFLA_RTA(ifi), IFLA_PAYLOAD(n));
+       ifname = rta_getattr_str(tb[IFLA_IFNAME]);
+       if (ifname == NULL)
+               return 0;
+
+       if (im) {
+               /* change to existing entry */
+               if (strcmp(im->name, ifname) != 0) {
+                       hlist_del(&im->name_hash);
+                       h = namehash(ifname) & (IDXMAP_SIZE - 1);
+                       hlist_add_head(&im->name_hash, &name_head[h]);
+               }
+
+               im->flags = ifi->ifi_flags;
+               return 0;
+       }
+
+       im = malloc(sizeof(*im) + strlen(ifname) + 1);
+       if (im == NULL)
+               return 0;
+       im->index = ifi->ifi_index;
+       strcpy(im->name, ifname);
+       im->type = ifi->ifi_type;
+       im->flags = ifi->ifi_flags;
+
+       h = ifi->ifi_index & (IDXMAP_SIZE - 1);
+       hlist_add_head(&im->idx_hash, &idx_head[h]);
+
+       h = namehash(ifname) & (IDXMAP_SIZE - 1);
+       hlist_add_head(&im->name_hash, &name_head[h]);
+
+       return 0;
+}
+
+const char *ll_idx_n2a(unsigned int idx)
+{
+       static char buf[IFNAMSIZ];
+
+       snprintf(buf, sizeof(buf), "if%u", idx);
+       return buf;
+}
+
+static unsigned int ll_idx_a2n(const char *name)
+{
+       unsigned int idx;
+
+       if (sscanf(name, "if%u", &idx) != 1)
+               return 0;
+       return idx;
+}
+
+const char *ll_index_to_name(unsigned int idx)
+{
+       static char buf[IFNAMSIZ];
+       const struct ll_cache *im;
+
+       if (idx == 0)
+               return "*";
+
+       im = ll_get_by_index(idx);
+       if (im)
+               return im->name;
+
+       if (if_indextoname(idx, buf) == NULL)
+               snprintf(buf, IFNAMSIZ, "if%u", idx);
+
+       return buf;
+}
+
+int ll_index_to_type(unsigned idx)
+{
+       const struct ll_cache *im;
+
+       if (idx == 0)
+               return -1;
+
+       im = ll_get_by_index(idx);
+       return im ? im->type : -1;
+}
+
+int ll_index_to_flags(unsigned idx)
+{
+       const struct ll_cache *im;
+
+       if (idx == 0)
+               return 0;
+
+       im = ll_get_by_index(idx);
+       return im ? im->flags : -1;
+}
+
+unsigned ll_name_to_index(const char *name)
+{
+       const struct ll_cache *im;
+       unsigned idx;
+
+       if (name == NULL)
+               return 0;
+
+       im = ll_get_by_name(name);
+       if (im)
+               return im->index;
+
+       idx = if_nametoindex(name);
+       if (idx == 0)
+               idx = ll_idx_a2n(name);
+       return idx;
+}
+
+void ll_init_map(struct rtnl_handle *rth)
+{
+       static int initialized;
+
+       if (initialized)
+               return;
+
+       if (rtnl_linkdump_req(rth, AF_UNSPEC) < 0) {
+               perror("Cannot send dump request");
+               exit(1);
+       }
+
+       if (rtnl_dump_filter(rth, ll_remember_index, NULL) < 0) {
+               fprintf(stderr, "Dump terminated\n");
+               exit(1);
+       }
+
+       initialized = 1;
+}