lib, zebra: move "struct vrf" to be a lib module

Previously "struct vrf" is defined locally in zebra. Now it is moved
to be a lib module.

This is the first step to support multi-VRF in quagga. The
implementation is splitted into small patches for the purpose of
easy review.

* lib:
    "struct vrf" with basic members is defined in vrf.c. The member
    "void *info" is for user data.

    Some basic functions are defined in vrf.c for adding/deleting/
    looking up a VRF, scanning the VRF table and initializing the
    VRF module.

    The type "vrf_id_t" is defined specificly for VRF ID.

* zebra:
    The previous "struct vrf" is re-defined as "struct zebra_vrf";
    and previous "vrf" variables are renamed to "zvrf".

    The previous "struct vrf" related functions are removed from
    zbera_rib.c. New functions are defined to maintain the new
    "struct zebra_vrf".

    The names vrf_xxx are reserved for the functions in VRF module.
    So:
    - the previous vrf_table() are renamed to zebra_vrf_table();
    - the previous vrf_static_table() are renamed to
      zebra_vrf_static_table().

    The main logic is not changed.

    BTW: Add a statement to zebra_snmp.c telling that the SNMP is
         running only for the MIBs in the default VRF.

Signed-off-by: Feng Lu <lu.feng@6wind.com>
Reviewed-by: Alain Ritoux <alain.ritoux@6wind.com>
Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Acked-by: Vincent JARDIN <vincent.jardin@6wind.com>
Signed-off-by: David Lamparter <equinox@opensourcerouting.org>
diff --git a/lib/Makefile.am b/lib/Makefile.am
index fc02312..ac51fc6 100644
--- a/lib/Makefile.am
+++ b/lib/Makefile.am
@@ -13,7 +13,7 @@
 	sockunion.c prefix.c thread.c if.c memory.c buffer.c table.c hash.c \
 	filter.c routemap.c distribute.c stream.c str.c log.c plist.c \
 	zclient.c sockopt.c smux.c agentx.c snmp.c md5.c if_rmap.c keychain.c privs.c \
-	sigevent.c pqueue.c jhash.c memtypes.c workqueue.c
+	sigevent.c pqueue.c jhash.c memtypes.c workqueue.c vrf.c
 
 BUILT_SOURCES = memtypes.h route_types.h gitversion.h
 
@@ -28,7 +28,7 @@
 	str.h stream.h table.h thread.h vector.h version.h vty.h zebra.h \
 	plist.h zclient.h sockopt.h smux.h md5.h if_rmap.h keychain.h \
 	privs.h sigevent.h pqueue.h jhash.h zassert.h memtypes.h \
-	workqueue.h route_types.h libospf.h
+	workqueue.h route_types.h libospf.h vrf.h
 
 noinst_HEADERS = \
 	plist_int.h
diff --git a/lib/memtypes.c b/lib/memtypes.c
index 1a0c11f..3e599f6 100644
--- a/lib/memtypes.c
+++ b/lib/memtypes.c
@@ -69,14 +69,15 @@
   { MTYPE_PQUEUE,		"Priority queue"		},
   { MTYPE_PQUEUE_DATA,		"Priority queue data"		},
   { MTYPE_HOST,			"Host config"			},
+  { MTYPE_VRF,			"VRF"				},
+  { MTYPE_VRF_NAME,		"VRF name"			},
   { -1, NULL },
 };
 
 struct memory_list memory_list_zebra[] = 
 {
   { MTYPE_RTADV_PREFIX,		"Router Advertisement Prefix"	},
-  { MTYPE_VRF,			"VRF"				},
-  { MTYPE_VRF_NAME,		"VRF name"			},
+  { MTYPE_ZEBRA_VRF,		"ZEBRA VRF"				},
   { MTYPE_NEXTHOP,		"Nexthop"			},
   { MTYPE_RIB,			"RIB"				},
   { MTYPE_RIB_QUEUE,		"RIB process work queue"	},
diff --git a/lib/vrf.c b/lib/vrf.c
new file mode 100644
index 0000000..3ccbb99
--- /dev/null
+++ b/lib/vrf.c
@@ -0,0 +1,268 @@
+/*
+ * VRF functions.
+ * Copyright (C) 2014 6WIND S.A.
+ *
+ * This file is part of GNU Zebra.
+ *
+ * GNU Zebra 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, or (at your
+ * option) any later version.
+ *
+ * GNU Zebra is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with GNU Zebra; see the file COPYING.  If not, write to the
+ * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+ * Boston, MA 02111-1307, USA.
+ */
+
+#include <zebra.h>
+
+#include "vrf.h"
+#include "prefix.h"
+#include "table.h"
+#include "log.h"
+#include "memory.h"
+
+struct vrf
+{
+  /* Identifier, same as the vector index */
+  vrf_id_t vrf_id;
+  /* Name */
+  char *name;
+
+  /* User data */
+  void *info;
+};
+
+/* Holding VRF hooks  */
+struct vrf_master
+{
+  int (*vrf_new_hook) (vrf_id_t, void **);
+  int (*vrf_delete_hook) (vrf_id_t, void **);
+} vrf_master = {0,};
+
+/* VRF table */
+struct route_table *vrf_table = NULL;
+
+/* Build the table key */
+static void
+vrf_build_key (vrf_id_t vrf_id, struct prefix *p)
+{
+  p->family = AF_INET;
+  p->prefixlen = IPV4_MAX_BITLEN;
+  p->u.prefix4.s_addr = vrf_id;
+}
+
+/* Get a VRF. If not found, create one. */
+static struct vrf *
+vrf_get (vrf_id_t vrf_id)
+{
+  struct prefix p;
+  struct route_node *rn;
+  struct vrf *vrf;
+
+  vrf_build_key (vrf_id, &p);
+  rn = route_node_get (vrf_table, &p);
+  if (rn->info)
+    {
+      vrf = (struct vrf *)rn->info;
+      route_unlock_node (rn); /* get */
+      return vrf;
+    }
+
+  vrf = XCALLOC (MTYPE_VRF, sizeof (struct vrf));
+  vrf->vrf_id = vrf_id;
+  rn->info = vrf;
+
+  zlog_info ("VRF %u is created.", vrf_id);
+
+  if (vrf_master.vrf_new_hook)
+    (*vrf_master.vrf_new_hook) (vrf_id, &vrf->info);
+
+  return vrf;
+}
+
+/* Delete a VRF. This is called in vrf_terminate(). */
+static void
+vrf_delete (struct vrf *vrf)
+{
+  zlog_info ("VRF %u is to be deleted.", vrf->vrf_id);
+
+  if (vrf_master.vrf_delete_hook)
+    (*vrf_master.vrf_delete_hook) (vrf->vrf_id, &vrf->info);
+
+  if (vrf->name)
+    XFREE (MTYPE_VRF_NAME, vrf->name);
+
+  XFREE (MTYPE_VRF, vrf);
+}
+
+/* Look up a VRF by identifier. */
+static struct vrf *
+vrf_lookup (vrf_id_t vrf_id)
+{
+  struct prefix p;
+  struct route_node *rn;
+  struct vrf *vrf = NULL;
+
+  vrf_build_key (vrf_id, &p);
+  rn = route_node_lookup (vrf_table, &p);
+  if (rn)
+    {
+      vrf = (struct vrf *)rn->info;
+      route_unlock_node (rn); /* lookup */
+    }
+  return vrf;
+}
+
+/* Add a VRF hook. Please add hooks before calling vrf_init(). */
+void
+vrf_add_hook (int type, int (*func)(vrf_id_t, void **))
+{
+  switch (type) {
+  case VRF_NEW_HOOK:
+    vrf_master.vrf_new_hook = func;
+    break;
+  case VRF_DELETE_HOOK:
+    vrf_master.vrf_delete_hook = func;
+    break;
+  default:
+    break;
+  }
+}
+
+/* Return the iterator of the first VRF. */
+vrf_iter_t
+vrf_first (void)
+{
+  struct route_node *rn;
+
+  for (rn = route_top (vrf_table); rn; rn = route_next (rn))
+    if (rn->info)
+      {
+        route_unlock_node (rn); /* top/next */
+        return (vrf_iter_t)rn;
+      }
+  return VRF_ITER_INVALID;
+}
+
+/* Return the next VRF iterator to the given iterator. */
+vrf_iter_t
+vrf_next (vrf_iter_t iter)
+{
+  struct route_node *rn = NULL;
+
+  /* Lock it first because route_next() will unlock it. */
+  if (iter != VRF_ITER_INVALID)
+    rn = route_next (route_lock_node ((struct route_node *)iter));
+
+  for (; rn; rn = route_next (rn))
+    if (rn->info)
+      {
+        route_unlock_node (rn); /* next */
+        return (vrf_iter_t)rn;
+      }
+  return VRF_ITER_INVALID;
+}
+
+/* Return the VRF iterator of the given VRF ID. If it does not exist,
+ * the iterator of the next existing VRF is returned. */
+vrf_iter_t
+vrf_iterator (vrf_id_t vrf_id)
+{
+  struct prefix p;
+  struct route_node *rn;
+
+  vrf_build_key (vrf_id, &p);
+  rn = route_node_get (vrf_table, &p);
+  if (rn->info)
+    {
+      /* OK, the VRF exists. */
+      route_unlock_node (rn); /* get */
+      return (vrf_iter_t)rn;
+    }
+
+  /* Find the next VRF. */
+  for (rn = route_next (rn); rn; rn = route_next (rn))
+    if (rn->info)
+      {
+        route_unlock_node (rn); /* next */
+        return (vrf_iter_t)rn;
+      }
+
+  return VRF_ITER_INVALID;
+}
+
+/* Obtain the VRF ID from the given VRF iterator. */
+vrf_id_t
+vrf_iter2id (vrf_iter_t iter)
+{
+  struct route_node *rn = (struct route_node *) iter;
+  return (rn && rn->info) ? ((struct vrf *)rn->info)->vrf_id : VRF_DEFAULT;
+}
+
+/* Obtain the data pointer from the given VRF iterator. */
+void *
+vrf_iter2info (vrf_iter_t iter)
+{
+  struct route_node *rn = (struct route_node *) iter;
+  return (rn && rn->info) ? ((struct vrf *)rn->info)->info : NULL;
+}
+
+/* Get the data pointer of the specified VRF. If not found, create one. */
+void *
+vrf_info_get (vrf_id_t vrf_id)
+{
+  struct vrf *vrf = vrf_get (vrf_id);
+  return vrf->info;
+}
+
+/* Look up the data pointer of the specified VRF. */
+void *
+vrf_info_lookup (vrf_id_t vrf_id)
+{
+  struct vrf *vrf = vrf_lookup (vrf_id);
+  return vrf ? vrf->info : NULL;
+}
+
+/* Initialize VRF module. */
+void
+vrf_init (void)
+{
+  struct vrf *default_vrf;
+
+  /* Allocate VRF table.  */
+  vrf_table = route_table_init ();
+
+  /* The default VRF always exists. */
+  default_vrf = vrf_get (VRF_DEFAULT);
+  if (!default_vrf)
+    {
+      zlog_err ("vrf_init: failed to create the default VRF!");
+      exit (1);
+    }
+
+  /* Set the default VRF name. */
+  default_vrf->name = XSTRDUP (MTYPE_VRF_NAME, "Default-IP-Routing-Table");
+}
+
+/* Terminate VRF module. */
+void
+vrf_terminate (void)
+{
+  struct route_node *rn;
+  struct vrf *vrf;
+
+  for (rn = route_top (vrf_table); rn; rn = route_next (rn))
+    if ((vrf = rn->info) != NULL)
+      vrf_delete (vrf);
+
+  route_table_finish (vrf_table);
+  vrf_table = NULL;
+}
+
diff --git a/lib/vrf.h b/lib/vrf.h
new file mode 100644
index 0000000..7e05099
--- /dev/null
+++ b/lib/vrf.h
@@ -0,0 +1,96 @@
+/*
+ * VRF related header.
+ * Copyright (C) 2014 6WIND S.A.
+ *
+ * This file is part of GNU Zebra.
+ *
+ * GNU Zebra 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, or (at your
+ * option) any later version.
+ *
+ * GNU Zebra is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with GNU Zebra; see the file COPYING.  If not, write to the
+ * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+ * Boston, MA 02111-1307, USA.
+ */
+
+#ifndef _ZEBRA_VRF_H
+#define _ZEBRA_VRF_H
+
+/* The default VRF ID */
+#define VRF_DEFAULT 0
+
+/*
+ * VRF hooks
+ */
+
+#define VRF_NEW_HOOK        0   /* a new VRF is just created */
+#define VRF_DELETE_HOOK     1   /* a VRF is to be deleted */
+
+/*
+ * Add a specific hook to VRF module.
+ * @param1: hook type
+ * @param2: the callback function
+ *          - param 1: the VRF ID
+ *          - param 2: the address of the user data pointer (the user data
+ *                     can be stored in or freed from there)
+ */
+extern void vrf_add_hook (int, int (*)(vrf_id_t, void **));
+
+/*
+ * VRF iteration
+ */
+
+typedef void *              vrf_iter_t;
+#define VRF_ITER_INVALID    NULL    /* invalid value of the iterator */
+
+/*
+ * VRF iteration utilities. Example for the usage:
+ *
+ *   vrf_iter_t iter = vrf_first();
+ *   for (; iter != VRF_ITER_INVALID; iter = vrf_next (iter))
+ *
+ * or
+ *
+ *   vrf_iter_t iter = vrf_iterator (<a given VRF ID>);
+ *   for (; iter != VRF_ITER_INVALID; iter = vrf_next (iter))
+ */
+
+/* Return the iterator of the first VRF. */
+extern vrf_iter_t vrf_first (void);
+/* Return the next VRF iterator to the given iterator. */
+extern vrf_iter_t vrf_next (vrf_iter_t);
+/* Return the VRF iterator of the given VRF ID. If it does not exist,
+ * the iterator of the next existing VRF is returned. */
+extern vrf_iter_t vrf_iterator (vrf_id_t);
+
+/*
+ * VRF iterator to properties
+ */
+extern vrf_id_t vrf_iter2id (vrf_iter_t);
+extern void *vrf_iter2info (vrf_iter_t);
+
+/*
+ * Utilities to obtain the user data
+ */
+
+/* Get the data pointer of the specified VRF. If not found, create one. */
+extern void *vrf_info_get (vrf_id_t);
+/* Look up the data pointer of the specified VRF. */
+extern void *vrf_info_lookup (vrf_id_t);
+
+/*
+ * VRF initializer/destructor
+ */
+/* Please add hooks before calling vrf_init(). */
+extern void vrf_init (void);
+extern void vrf_terminate (void);
+
+#endif /*_ZEBRA_VRF_H*/
+
diff --git a/lib/zebra.h b/lib/zebra.h
index a5ed20e..e88a629 100644
--- a/lib/zebra.h
+++ b/lib/zebra.h
@@ -522,6 +522,9 @@
 typedef u_int16_t zebra_size_t;
 typedef u_int16_t zebra_command_t;
 
+/* VRF ID type. */
+typedef u_int16_t vrf_id_t;
+
 /* FIFO -- first in first out structure and macros.  */
 struct fifo
 {